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  • 1
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary Systolic pressor effects after i.v. injection of tyramine (TA) were recorded in 13 patients before and during treatment with nortriptyline (NT) in doses of 1.4–5 mg/kg/day for 3–4 weeks. After NT a several fold decrease in the responsiveness to TA occurred. Patients given the same dose of NT showed markedly different decreases in the responsiveness to TA. There was no correlation between the blockade of the TA pressor effects and the dose of NT employed but there was an excellent correlation between the blockade and the plasma level of NT (p〈0.001 and p〈0.005 respectively). TA pressor effects were not changed in a small control group of depressed patients after treatment with E.C.T. The relationship between kinetics and effects of tricyclic antidepressants is discussed. The steady-state plasma level of NT seems to be an important determinant of its effects.
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  • 2
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary In a dose of 40 mg, sotalol (MJ 1999) was more potent than 10 mg propranolol in blocking the cardiovascular effects of isoproterenol (5 healthy males, age 22–28 years). In a dose of 10 mg sotalol had weaker blocking properties. In a dose of 10 mg, propranolol under true basal conditions significantly decreased cardiac output (1.7 ± 0.34 1), stroke volume (31 ± 11 ml) and “heart work” (− 20 ± 7%), and increased the peripheral resistance (+35 ± 6%). Sotalol (10–40 mg i.v.) had no significant actions on cardiac output or any other cardiac function. There were statistically significant differences in the haemodynamic effects of sotalol and propranolol at doses producing a similar adrenergic β-receptor blocking effect.
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  • 3
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary Intravenous administration of the beta-adrenergic blocking drug, alprenolol, to a group of patients with severe obstructive disease of the airways caused no deterioration of symptoms and a clinically insignificant fall in FEV1 in the majority. A minor reduction in PaO2 occurred which suggests that alprenolol may cause local hypoventilation and/or pulmonary arteriovenous shunting. The presence of obstructive disease of the airways does not seem to pose an absolute contraindication to the use of alprenolol, although caution must be exercised in its use in such patients.
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  • 4
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary In 40 depressed patients treated with 25 or 50 mg nortriptyline (NT) t. i. d. for 3 weeks the following circulatory variables were observed prior to and during drug therapy: heart rate and blood pressure at rest (in supine and standing positions), working capacity, ECG at rest and during exercise on a bicycle ergometer. During administration of NT the heart rate increased significantly at rest in both supine and standing positions, but the orthostatic heart rate reaction remained unchanged. Diastolic blood pressure in the supine position rose slightly; in the standing position the pretreatment increase in diastolic pressure was abolished. The positive chronotropic effect did not correlate with the steady-state plasma level of NT. In one patient on NT a right bundle branch block appeared during the work test; in the remaining 39 patients the ECG records at rest and during exercise showed no adverse effects of NT.
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  • 5
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary The effect of nicotinic acid and pentaerythritoltetranicotinate (Perycit®, Bofors) on cardiac output, FFA-level and content of free nicotinic acid in plasma was studied in healthy humans —. Nicotinic acid infused intravenously in a dose of 0.05 mg/kg/min for 180 min or administered orally in a dose of 1 g increased the cardiac output maximally by about 20 per cent for 30–60 min. The total peripheral resistance decreased and the pulse rate and stroke volume increased moderately. Pentaerythritoltetranicotinate produced the same effects but the increase of cardiac output lasted longer. In all series there was a considerable decrease of the FFA-level of plasma. The increase of the plasma concentration of nicotinic acid was most pronounced after 1 g of nicotinic acid administered orally. The effect on the cardiac output was greatest the longer the plasma concentration of nicotinic acid increased.
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  • 6
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary The effect of adding amiloride or spironolactone to an antihypertensive regimen which consisted of hydroehlorothiazide and guanethidine was studied. Amiloride and spironolactone produced very similar effects including significant urinary sodium loss, decrease in serum bicarbonate, potassium retention and increase in serum potassium. In two groups of hypokalemic patients, neither spironolactone nor amiloride caused further lowering of blood pressure. Temporary moderate hyperkalaemia occurred in one patient when amiloride was substituted for spironolactone. The administration of the two drugs together or in close succession appears to be hazardous, probably due to synergistic effects.
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  • 7
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary Comparative studies were performed for about fifteen months in 26 patients with chronic atrial fibrillation to evaluate the efficiency of Quinidine Durules or quinidine sulphate in maintaining sinus rhythm. There was no difference in the two groups as to underlying disease, type of rhythmic disturbance and its duration, nor in the frequency of occurrence of congestive heart failure prior to DC shock applied for restoration of sinus rhythm. On the basis of our observations made during a period of about 15 months adequate doses of quinidine sulphate and Quinidine Durules — monitored by the plasma quinidine levels — proved equally suited for the maintenance of sinus rhythm. Quinidine sulphate elicited side effects (toxic symptoms) more frequently than did the long-acting Quinidine Durules. With two daily dosages of Quinidine Durules — more convenient for the patient than four daily administrations of quinidine sulphate — a more stable plasma quinidine level was maintained. That in turn might explain the less frequent occurrence of side effects.
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  • 8
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary A clinico-pharmacological study of depot tetracosactrin in four fixed-dosage regimes was undertaken in 37 hospitalised patients with severe active rheumatoid arthritis. The regimes were: 0.25 mg daily (6 patients), 0.25 mg alternate days (6 patients), 0.5 mg daily (10 patients) and 0.5 mg alternate days (15 patients). Marked symptom relief was associated with a fall in the articular index, E.S.R. and serum globulins but also accompanied by a high incidence of steroid side effects including mooning of the face, weight gain, fluid retention, hirsutes, pigmentation and significant hypokalaemia in the higher dosage schedules despite oral potassium supplements. Maximal plasma 11-OHCS responses increased with duration of therapy in all groups, but parallel measurements of intraocular pressure appeared to be unrelated and did not rise significantly with treatment. It is suggested that to obtain optimum results in any individual, the dosage regime is likely to require adjustment according to the activity of the disease and susceptibility to side effects.
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  • 9
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    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
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  • 10
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    Springer
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary Thirteen patients, eleven of whom had asthma, were treated with ordinary therapeutic dosages of Celeston Chronodose (a mixture of disodium phosphate and of acetate of betamethasone) or Depo-Medrol (6-methylprednisolone acetate). Duration of the effect of one single intramuscular injection lasted from 1–6 days, if judged by clinical improvement and by suppression of plasma 11-OHCS and by the blood eosinophil count. It was concluded that parenteral administration of depotcorticosteroids per mg does not prolong the effect of the corticosteroids as compared with the oral route.
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  • 11
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary In a controlled clinical trial 6-azauridinetriacetate, a drug that inhibits the synthesis of pyrimidine “de novo”, had a therapeutic effect in psoriasis. The general tolerance of the drug is good. However, with the dosage of 150 mg/kg/day the leucocytes and erythrocytes of the peripheral blood may drop after 5–6 weeks, the effect depending on the dosage. 270 mg/kg/day may be administered for several weeks. 400 mg/kg/day have early therapeutic effects but cannot be administered for longer periods because of the side-effects mentioned. Only serious cases of psoriasis should be treated with this drug, as with cytostatics in general.
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  • 12
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary The data of a double-blind cooperative trial of thiamphenicol (TP), tetracycline (TE) and placebo (PL) in a two-week oral treatment of acne vulgaris were subjected to a study of the observers' attitudes. The study provided no evidence that the “PL-optimistic” doctors judged either antibiotic more favorably than the “PL-pessimistic”. A technique for analyzing factorial experiments when the data are frequencies m unbalanced groups was used in a computerized form to evaluate the effects of the oral treatments as well as the interactions with the factors “Sex”, “Severity” and “Topical treatment”. The advantage of TP (63% satisfactory responses) over PL (34%) was proved beyond doubt, irrespective of any factors studied; the addition of a topical treatment is a useful cofactor only in the severe forms in female patients. The advantage of TE (50% overall satisfactory responses) over PL was detected in female patients only. This finding, as well as the potent action of TP, are discussed in view of the acne ameliorating mechanism/s of these antibiotics.
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  • 13
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary A new beta-adrenergic antagonist, LB 46, was given intravenously in a dose of 0.01 mg/kg to ten patients with minor cardiac abnormalities. The haemodynamic response to the compound was evaluated both at rest and during exercise in supine position. At rest there was a modest reduction in heart rate and cardiac output; a decrease in the maximal right ventricular dp/dt was the only indication of negative inotropy. More marked negative chronotropic and inotropy effects became apparent during exercise. No side-effects were observed.
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  • 14
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary A new inhibitor of adrenocortical secretion, amino-glutethimide (Elipten, CIBA) was used to treat 37 patients with secondary hyperaldosteronism and oedema due to congestive heart failure, cirrhosis of the liver and idiopathic oedema. 32 of the 37 patients responded with a significant sodium diuresis secondary to decreased tubular reabsorption of sodium. Their aldosterone excretion fell significantly after Elipten, and the plasma renin activity showed a significant rise. In 2 of the 5 patients resistant to a combination of Elipten with Lasix, a sodium diuresis followed additional treatment with triamcinolone. A skin rash occurred after Elipten in 1 of the 37 patients. — Elipten may be used with advantage for the treatment of selected patients with secondary hyperaldosteronism and oedema. In some ways it is better than the alternative treatment with spironolactones.
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  • 15
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary 1. The metabolic fate of intravenous and oral propranolol has been studied after single doses in man using 14C labelled propranolol. — 2. After oral administration there is virtually complete absorption and peak blood levels of propranolol and 4-hydroxy propranolol (a beta blocking metabolite) are seen at about 1 1/4 h after administration. Studies in normal subjects confirm that the maximum degree of beta blockade occurs at this time. — 3. Following intravenous administration, no 4-hydroxy propranolol is seen and the possible reasons for this are discussed. — 4. Excretion of the administered radio-active dose is mainly in the urine, with only 1%–4% of the administered radio-activity appearing in the faeces after both intravenous and oral dosing. — 5. The major metabolite so far identified in the urine is naphthoxylactic acid, which accounts for approximately 20% and 40% of oral and i.v. doses respectively. — 6. The greater proportion of radio-activity excreted in the urine (30–60% of the administered dose) is as yet unidentified although it may be a conjugate of propranolol. The level of total blood radio-activity following both intravenous and oral propranolol is very much higher than that of either propranolol or 4-hydroxy propranolol. The major portion of this blood radio-activity appears to be the same as the unidentified urinary metabolite. — 7. Following intravenous doses the decline of pharmacological response roughly parallels that of propranolol concentration in the plasma, and does not correlate with the plasma concentration of the unidentified metabolite.
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  • 16
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Description / Table of Contents: Zusammenfassung Bei 7 gesunden Versuchspersonen und bei 12 Altersdiabetikern verschiedenen Schweregrades wurden die Insulinsekretion und das Blutzuckerverhalten nach alleiniger Nahrungsaufnahme und nach zusätzlicher oraler Gabe von Tolbutamid oder HB 419 geprüft. 5 mg HB 419 erhöhen die Insulinsekretion bei gesunden Versucbspersonen und bei Patienten mit leichtem Altersdiabetes etwas starker als 1 g Tolbutamid. Die morgendliche Gabe der SH-Präparate verstärkt auch noch die Insulinsekretion nach der Mittagsmahlzeit, wahrscheinlich durch eine Sensibilisierung der Betazellen gegenüber dem physiologischen Reiz der aufgenommenen Nahrung. Normalpersonen and Patienten mit leichtem Altersdiabetes (diätetisch oder mit alleiniger SH-Therapie kontrolliert) beantworten eine abendliche, zweite SH-Gabe erneut mit einer Erhöhung der Insulinsekretion verglichen mit dem Kontrolltag. Bei Patienten mit oral sehlecht kontrollierbarem Diabetes ist die abendliche SH-Gabe wirkungslos.
    Notes: Summary Insulin secretion and the concentration of blood sugar were determined in 7 normal adults and in 12 patients with maturity-onset diabetes mellitus of different degrees of severity. Insulin secretion was stimulated on three different days by a) 3 meals only, b) 3 meals plus 1 g of tolbutamide b.i. d., and c) 3 meals plus 5 mg of HB 419 b.i.d. In the normal subjects and in the mild diabetics the effect of 5 mg of HB 419 (orally) on insulin secretion is slightly more pronounced than that of 1 g of tolbutamide. Administration of the sulfonylurea compounds at 8.00 a. m. still provokes an increased secretion of insulin after lunch (12:00 noon) as compared with the control day. That effect seems to be best explained by increased sensitivity of the pancreatic beta-cells to the stimulus of food intake. In normal subjects and in mild diabetics insulin secretion is again augmented by a second administration of tolbutamide or HB 419 at 18:00 p.m., whereas the second dose is ineffective in patients not well maintained by diet or sulfonylureas alone.
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  • 17
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Description / Table of Contents: Zusammenfassung Das Sulfonamid Sulfaphenazol verstärkt den hypoglykamisierenden Effekt von Tulbutamid über eine Verlängerung der Serumhalbwertzeit für Tolbutamid. Es wird untersucht, an welcher Stelle des Abbauweges Sulfaphenazol die Metabolisierung von Tolbutamid im menschlichen Organismus hemmt. Da Sulfaphenazol nur die Serumhalbwertzeit des noch nicht metabolisierten Tolbutamid signifikant verlängert, nicht jedoch die Serumhalbwertzeit seiner Metaboliten Hydroxyl-Tolbutamid und Carboxyl-Tolbutamid, muß angenommen werden, daß Sulfaphenazol den ersten Abbauschritt von Tolbutamid, d.h. die Hydroxylierung, verzögert, während der nächste Abbauschritt, die Carboxylierung, ungehindert in wenigen Minuten abläuft.
    Notes: Summary Sulfaphenazol potentiates the hypoglycaemic effect of tolbutamide by prolonging its half-life in plasma. The attempt has been made in man to localize the step in tolbutamide metabolism which is inhibited by sulfaphenazol. It was found to prolong the half-life of undegraded tolbutamide without interfering with the elimination of its metabolites hydroxy-tolbutamide and carboxy-tolbutamide. It seems that sulfaphenazol blocks the first stage of tolbutamide metabolism, its hydroxylation, whilst the second step — carboxylation — remains uninhibited and is accomplished in a few minutes.
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  • 18
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary Taloximine is a phthalazine derivative with a respiratory stimulant action on the peripheral chemoreceptors. Peak plasma levels of taloximine after oral administration coincided with peak hyperventilation accompanied by a respiratory alkalosis, a, fall in venous pCO2, and a rise in plasma and urinary pH. — Taloximine was excreted in urine and bile. Metabolites included a phthalazinone, demethylated taloximine and other metabolites in ring hydroxylated form. Sulphated and glucuronated taloximine and metabolites were formed.
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  • 19
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Description / Table of Contents: Zusainmenfassung 1. Bei neugeborenen Kindern sinkt die Amidopyrinkonzentration im Serum nach i.v.-Amidopyrin-Injektion am 8. Lebenstag schneller ab als am 1. Lebenstag. — 2. Durch Behandlung mit Phenylbutazon bzw. Phenobarbital vom 2. his 7. Lebenstag wird der Abfall der Amidopyrinkonzentration im Serum am 8. Lebenstag nicht beschleunigt. — 3. Bei den mit Phenylbutazon oder Phenobarbital behandelten Kindern waren die Bilirubinkonzentrationen im Serum geringer und die Maximalwerte warden friiher erreicht als bei der Kontrollgruppe. — 4. Phenylbutazon und Phenobarbital steigern beim menschlichen Neugeborenen die Bildung von Gerinnungsfaktoren. Die Wirkung von Phenobarbital ist stärker ausgeprägt als die von Phenylbutazon.
    Notes: Summary 1. The rate of fall in the serum concentration of amidopyrine given intravenously to newborn infants is more rapid on the 8th than on the 1st day of life. — 2. Treatment of neonates with phenylbutazone or phenobarbitone does not increase the rate of decline of serum levels of amidopyrine. — 3. The total concentration of bilirubin in serum was lower and maximum values were reached earlier in the group of newborns treated with phenylbutazone or phenobarbitone than in the control group. —4. In newborns both phenylbutazone and phenobarbitone enhance the formation of blood clotting factors. In this respect, phenobarbitone is more potent than phenylbutazone.
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  • 20
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Description / Table of Contents: Zusammenfassung Während einer 4-stündigen Inkubationszeit wurden in Kulturen leukamischer Zellen die Einbauraten von Tritium -markiertem Desoxyuridin und Thymidin in die DNS untersucht. — 1. Die Zugabe von unmarkiertem Thymidin hemmt den Einbau von 3H-Desoxyuridin, und entsprechend hemmt unmarkiertes Desoxyuridin den Einbau von 3H-Thymidin. Diese Zusammenhänge werden durch den hemmenden Rückkoppelungsmechanismus von Thymidintriphosphat auf die Phosphorylierung von Desoxyuridin und Thymidin erklärt. — 2. Methotrexat und 5-Fluorouracil hemmen durch Blockierung der Thyminmethylgruppen-de novo-Synthese den Einbau von Desoxyuridin. Unter der Einwirkung dieser Medikamente wird Thymidin vermehrt für die DNS-Synthese verwertet, was sich durch Fortfall der hemmenden Rückkoppelung von Thymidintriphosphat auf die Thymidin-Kinase erklären läßt. — 3. Cytosin-Arabinosid bewirkt eine Herabsetzung der Desoxyuridin- und Thymidin-Einbauraten. Da hier sowohl die Bildung von Thymidintriphosphat als auch von Desoxycytidintriphosphat als Substrate der DNS-Polymerase gehemmt ist, kann trotz gesteigerter Thymidin -Kinase Thymidin nicht fur die DNS-Synthese verwertet werden. — 4. Kombinierte Aktivitäts-bestimmungen von Enzymen, die durchverschiedene Cytostatika beeinflußt werden, in Zellcytolysaten und die in dieser Arbeit beschriebenen Untersuchungen der Einbauraten radioaktiv markierter DNS-Vorstufen in Zellkulturen vor und im Beginn einer spezifischen Behandlung sind geeignet, die Ansprechbarkeit der Leukämiezellen auf biochemischer Basis zu beurteilen.
    Notes: Summary The incorporation of 3H-labelled desoxyuridine and thymidine into DNA was investigated by 4 h incubation of leukaemic cells. 1. The incorporation of 3H-desoxyuridine is inhibited by unlabelled thymidine and similary unlabelled desoxyuridine inhibits the utilisation of 3H-thymidine. These effects can be accounted for by feedback inhibition of desoxyuridine kinase and thymidine kinase by thymidine triphosphate. — 2. Methotrexate and 5-fluorouracil inhibit the incorporation of desoxyuridine by blocking de novo synthesis of thymine methyl groups. Under the influence of these drugs there is increased utilisation of thymidine for DNA-synthesis because of lessened activity of the negative feed back control of thymidine kinase by thymidine triphosphate. —3. Cytosine arabinoside also produces decreased incorporation of both desoxyuridine and thymidine. In this case the synthesis of thymidine triphosphate and deoxycytidine is inhibited, both of which are substrates of DNA-polymerase. Therefore, although activity of thymidine kinase is increased, the thymidine cannot be utilized for DNA-synthesis. — 4. It should be possible to develop rational therapy for leukaemia and to assess the sensitivity of leukaemic cells by determining the uptake of radio-active DNA precursors and the activities of various enzymes in intact cells and cytolysates before and during treatment.
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  • 21
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Description / Table of Contents: Zusammenfassung 1. Es wird ein Verfahren beschrieben, welches es gestattet, ohne Aufstellung der bisher notwending gewesenen Bilanzen die Absorption eines Stoffes aus einem (oder mehrereren) beliebigen Depots während der gesamten Dauer des Absorptionsprozesses zu verfolgen. —2. Die einzigen benötigten Daten sind die verabreichten Dosen und die Konzentrationsverläufe in der Kreislaufflüsigkeit nach intravenöser Injektion bzw. nach beliebiger, nicht-intravasaler Applikation in ein Absorptionsdepot. —3. Die Anwendung des Verfahrens kann auf rein pragmatischen Weg erfolgen. Es werden keinerlei mathematische Prozeduren benötigt, auch wenn es sich um die Annahme eines Mltikompatimenten-Systems handelt.
    Notes: Summary 1. From the principle of corresponding areas of a method has been derived for measuring absorption of a drug during an entire period of treatment. —2. Simple measurements of input or output are useless. The only data required are estimates of the changing the concentrations in the blood, either after intravenous injection, or after administration of the same dose by any other route the absorptive properties of which are being measured. — 3. The procedure can be applied simply and without mathematical computations. It is also suitable for the study of multicompartment systems.
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  • 22
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Description / Table of Contents: Zusammenfassung 1. Nach oraler Gabe von Diacethiamin tritt ein starker Anstieg von Thiamin und von Thiaminpyrophosphat im Vollblut auf. Diacethiamin 1st im Blut kaum nachweisbar. — 2. Diacethiamin permeiert in die rote Blutzelle, wird dort in Thiamin umgewandelt und tritt dann aus dem. Erythrocyten in das umgebende Medium aus. — 3. Der Permeationsvorgang des Diacethiamins unterscheidet sich von dem des Thiamins und des Thiaminpyrophosphates.
    Notes: Summary 1. In man a marked increase was found in the blood levels of thiamine and thiamine pyrophosphate after oral administration of diacethiamine. — 2. Diacethiamine penetrates into erythrocytes where it is converted to thiamine which then permeates back into the surrounding medium. The red cell membrane is not involved in this process which is not an enzymatic reaction. The synthesis of thiamine pyrophosphate from thiamine mainly occurs in other tissues, and is slower than this reaction. — 3. Diacethiamine penetrates the membrane of red cells by a different mechanism from that employed by thiamine or thiamine pyrosphosphate.
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  • 23
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    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
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  • 24
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary Various aspects of the control of adrenal cortical function are considered and the use of plasma cortisol assays for the evaluation of hypothalamic-pituitary-adrenal (HPA) function are discussed. With these methods the effects of steroid therapy causing suppression of HPA function have been shown and by contrast it has been found that patients receiving long term daily ACTH therapy in general retain HPA responsiveness. Attempts to combine steroid and ACTH therapy were unsuccessful.
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  • 25
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary Small general purpose analog computers are not usually equipped for iterative computation. Since multiple dosage problems are often encountered in pharmacokinetic studies an approximating program is proposed for rapid estimation and curve fitting. The program produces an input function simulating a staircase by integration only of the positive differentials of a sequence of rectangular impulses. The program is used to compute the maximum and minimum concentration factors of Sparteine and Quinidine as examples of two substances obeying first order kinetics. It is apparent from the results that the choice of dosage schedules is restricted both by the pharmacological and the pharmacokinetic properties of the drugs.
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  • 26
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary Plasma levels of sparteine were determined in two groups of 8 patients each of whom received 200 mg of sparteine sulphate (Depasan®) intravenously and orally. A method was developed for the determination of sparteine in biological fluids, relying on solvent extraction and gas chromatography. After oral administration, 69.4% of the sparteine was absorbed and peak plasma levels were reached after 46.5 min. After intravenous injection the plasma levels declined with a half life of 117 min. When sparteine is given intravenously, 34.2% of the dose administered is excreted in the urine in the next 24 h as unchanged sparteine. Two metabolites were found in the urine but have not yet been identified. They contribute only a few percent to the total urinary excretion of sparteine. Approximately 50% of sparteine is bound to plasma proteins. — The pharmacokinetics of sparteine after intravenous administration can be described in terms of a one-compartment model. —The tissue distribution of sparteine was studied in preliminary experiments in rats. The drug was accumulated in several tissues, with the greatest concentration in the lungs. The hypothesis is advanced that drugs, which are organic bases with high pKa-values and high lipid solubility, are concentrated mainly in the lungs, followed by the adrenals, spleen, and the heart.
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  • 27
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary Plasma concentrations of diphenylhydantoin (DPH) were measured in six infants, 3 to 78 days old, who received about 10 mg/kg/day, orally or intramuscularly because of convulsions. Unexpectedly, the levels found were only half of those noted previously in adults treated with 5 mg/kg/day.
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  • 28
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    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary A formula has been derived for the calculation of “effective” serum concentration based on the assumption of both exponential absorption and exponential elimination of an administered drug. In order to permit quantitative comparisons of different drugs and/or different dosage schedules, a new term is proposed called “action” or “COTT” (for “concentration times time”).
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  • 29
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary Intravenous diazoxide produced an immediate marked hypotension in both mild and severe hypertensive patients. Depression of vasomotor reflexes, tested by the Valsalva overshoot, and of pressor responsiveness to noradrenaline was found only in the group of mild hypertensives. Decreased pressor reactivity to noradrenaline was not due to a nonspecific vascular effect of diazoxide, because pressor responsiveness to angiotensin was simultaneously increased. Renal tubular reabsorption of sodium and water was increased shortly after injection of diazoxide, and there was also a significant retention of potassium. Correlation studies suggest that interference with vasomotor reflexes, and with vascular responsiveness to the sympathetic transmitter, can account only in part for the hypotensive action of diazoxide. The possible rôles of water and electrolyte redistribution remain to be elucidated.
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  • 30
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary A dose of 250 mg (2.5–3.5 mg/kg body weight) of TMB-4 was given by i.m. injection to 12 healthy male subjects. The concentration of oxime in blood reached 2 μ/ml blood in 5 min and was sustained above this level for the subsequent 2.5 h. Within the first 4 h after its administration, 46% of the oxime was excreted in the urine. Observations on subjective manifestations following administration of the oxime and its effect on the cardiovascular and respiratory system indicate that TMB-4, in the dose range studied, is as well tolerated as other oximes in doses which would be expected to have a comparable antidotal action in dialkylphosphate poisoning. The results are discussed in relation to published information on other oximes.
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  • 31
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary In a controlled clinical trial, fifty-three chronic schizophrenic female subjects were treated with either chlorpromazine (N = 35) or placebo (N = 18). The mean serum cholesterol concentration increased by 8 mg per 100 ml in the chlorpromazine group while declining 30 mg per 100 ml in the placebo group. The adjusted mean difference in the analysis of covariance (26 mg per 100 ml) was statistically significant and in general agreement with previous findings attributing hypercholesterolemic activity to chlorpromazine. Thyroid and liver function in this group of patients remained relatively undisturbed and did not account for the cholesterol changes.
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  • 32
    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Description / Table of Contents: Zusammenfassung 1. Es wind eine Methode zur dünnschichtchromatographischen Trennung und quantitativen spektrophotofluorometrischen Bestimmung von Furosemid im Harn angegeben. — 2. Kranke mit Lebercirrhose scheiden nach i. v. und oraler Applikation weniger Furosemid im Harn aus als gesunde Kontrollpersonen. Die Halbwertszeit der renalen Elimination von Furosemid ist bei Cirrhose-Kranken in der ersten raschen Phase bei beiden Applikationsformen verlängert. Mit der verminderten Ausscheidung von Furosemid ist eine geringere Diurese in den ersten Stunden nach Zufuhr des Salureticums korreliert. — 3. Gesunde und Leberkranke scheiden zusätzlich einen Metaboliten im Harn aus, der nicht identisch mit 4-Chlor-5-sulfamyl-anthranils↑re ist. Es wird vermutet, daß es sich um ein Glucuronsäure-gebun-denes Derivat handelt.
    Notes: Summary 1. A method is described for the estimation of furosemide in urine which employs thin layer chromatography and quantitative spectrofluorimetry. — 2. After its oral or intravenous use, cirrhotics excreted less furosemide in urine than the controls. They showed prolongation of the half-time of the initial rapid phase of excretion which could be correlated with their slower initial diuresis. — 3. In the urines of both controls and cirrhotics an unidentified metabolite of furosemide was detected, possibly a glucuronate. It was shown not to be 4-chloro-5-sulphanylamthranilic acid.
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  • 33
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    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
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  • 34
    ISSN: 1432-1041
    Keywords: Drug therapy ; analeptics ; respiratory ; insufficiency ; taloximine ; ethamivan
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary A new peripherally acting respiratory stimulant taloximine is shown in a limited double-blind controlled study to be an effective analeptic agent, though probably no more so than ethamivan, in chronic bronchitic patients in moderate cardio-respiratory failure as a result of acute infective exacerbations.
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  • 35
    ISSN: 1432-1041
    Keywords: Amphetamine ; drug dependence ; pharmacokinetics ; amphetamine psychosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary Eighteen subjects with amphetamine psychosis were studied with respect to fluid balance, intensity and duration of psychotic symptoms, urinary and plasma amphetamine levels and the relative amounts of unchanged drug and metabolites in urine. On admission to hospital about half of the psychotic patients were dehydrated, the water lack being up to 6.7% of total body weight. The dehydrated subjects had lower renal clearances of amphetamine because of lower rates of urine production. As noted previously there was a strongly positive correlation between urinary pH and the half life (T 1/2) of plasma amphetamine, with an increase inT 1/2 of about 7 h for every unit increase in urinary pH. Patients with alkaline urine had intense psychoses lasting for about 4 1/2 days after the last dose of amphetamine. In patiens with acid urine, the psychotic symptoms were milder, and of about 2 days duration. No correlation was found between the degree of psychosis in different subjects and the plasma levels of the drug. — The ratio between the amounts of labelled metabolites and unchanged drug excreted in urine rose for each day after administration of3H-amphetamine, implying a slower excretion rate for the metabolites than for the parent drug. The relative proportion of metabolites was higher in patients with an alkaline urine, being more than 90% after the first day. — When amphetamine (200 mg i.v.) was given to nonpsychotic, dependent subjects, the peak plasma levels (mean 423 ng/ml) exceeded the highest levels observed during the first day in psychotic patients. However, no psychotic symptoms were observed in these subjects. The volumes of distribution calculated from the monoexponential elimination curves were higher than those previously reported in nondependent subjects. — With an alkaline urine a group of nonpsychotic amphetamine-dependent subjects had significantly longer plasmaT 1/2 (p〈0.05) than a group of drug-naive control subjects. The results suggest that increased tissue binding may be a component in tolerance to amphetamine in dependent humans.
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  • 36
    ISSN: 1432-1041
    Keywords: Exophthalmos ; guanethidine ; thyroxine ; prednisolone ; metronidazole
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary The degree of exophthalmos and the width of the palpebral fissure were studied serially in 58 previously thyrotoxic patients, who were divided into 6 treatment groups: 1. guanethidine eye drops; 2. oral thyroxine; 3. guanethidine eye drops and oral thyroxine; 4. guanethidine and prednisolone eye drops; 5. napththazoline nitrate 0.1% and zine sulfate 0.5% eye drops; and 6. metronidazole orally. Exophthalmos increased significantly in the first and third group, and the palpebral fissure decreased in the first group. It was concluded that guanethidine eye drops should be given when there is marked lid retraction with minimal exophtalmos; that prednisolone eye drops are not indicated in endocrine exophthalmos; and that the combination of guanethidine eye drops with oral thyroxine in different dosages is worth further study.
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  • 37
    ISSN: 1432-1041
    Keywords: Sulphonamides ; sylfametopyrazine ; pharmacokinetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary The pharmacokinetics of sulfametopyrazine were studied for seven days after a single oral dose of 2 g. in healthy volunteers in order to establish its chemotherapeutic value. — The appearance and disappearance of the drug in the plasma were evaluated both for compounds with a free amino group and for total sulphonamides. The half-life and absorption, distribution, elimination and excretion coefficients were calculated, as well as the concentrations in plasma water and interstitial fluid. The estimated drug concentrations in the urine agreed with those calculated from the excretion coefficients. — In all subjects at the end of the seventh day the concentrations in all body compartments of active compounds exceeded the minimum required for a therapeutic effect. The highest concentrations found in the urine were always significantly lower than the drug's basal solubility at pH 5, thus excluding any risk of crystalluria.
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  • 38
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    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
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  • 39
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    ISSN: 1432-1041
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
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  • 40
    ISSN: 1432-1041
    Keywords: Allopurinol ; urate formation ; uric acid ; hydroxypurines ; RNS-load
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Description / Table of Contents: Zusammenfassung Die tägliche Zufuhr von 413 mg Purin-N in Form von Ribonucleinsäure führt bei fünf Versuchspersonen innerhalb von acht Tagen zu einem Anstieg der Serumharnsäure von 3,86 mg% auf 6,97 mg% und der renalen Harnsäureausscheidung von 365 auf 786 mg pro Tag. — Diese exogene Uratquote wird nach Zulage von 400 mg Allopurinol/die vollständig beseitigt. — Der damit einhergehende Anstieg der Hypoxanthin-und Xanthinausscheidung im Urin zeigt bei den einzelnen Versuchspersonen jedoch quantitative Unterschiede. Bei zwei Personen wird die Verringerung der renalen Harnsäureausscheidung durch die vermehrte Oxypurinausscheidung fast vollständig ersetzt. Bei drei Personen ist der Gesamtpuringehalt des Urins nach Allopurinolverabreichung deutlich vermindert. — Die Einstellung der RNS-Zufuhr unter Fortsetzung der täglichen Allopurinolgabe führt bei allen Versuchspersonen im Laufe einer Woche nur zu einem geringgradigen Abfall der Serumharnsäure und renalen Harnsäureausscheidung unter die Werte der Kontrollperiode. — Allopurinol hemmt die Xanthinoxydase, die sich reichlich im Dünndarmepithel und der Leber findet. Die Annahme, daß Allopurinol im Dünndarmepithel während seiner Resorption angereichert wird, bietet eine einfache Erklärung für die quantitative Elimination der exogenen Uratquote bei Zufuhr dieses Arzneimittels. Die Verminderung der endogenen Uratquote durch Allopurinol ist gering und beträgt bei einer Dosis von 400 mg pro Tag 43,7%.
    Notes: Summary The daily administration to 5 patients of 413 mg of purine-N as ribonucleic acid was followed within 8 days by a rise in serum uric acid level from 3.86 to 6.97 mg/100 ml, and an increase in the urinary excretion of uric acid from 365 to 786 mg/day. This effect of exogenous urates was completely prevented by allopurinol 400 mg/day. — In certain individuals there was a simultaneous and quantitatively comparable increase in the urinary excretion of xanthine and hypoxanthine. In 2 cases the decrease in the urine content of uric acid was exactly paralleled by an increased excretion of these oxypurines; and in 3 cases total urinary purines were decreased after allopurinol. Despite continued administration of ribonucleic acid, daily treatment with allopurinol was found in all patients to produce a minimal fall in serum and urine urate levels. Allopurinol inhibits xanthine oxidase, the highest concentrations of which are found in the small bowel and liver. The absorption and intestinal recycling of allopurinol increase during such continuous treatment and so can account for the quantitative changes observed in the elimination of exogenous urate. The inhibitory effect of allopurinol (400 mg/day) on endogenous urate metabolism was slight and amounted to only 43.7%.
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  • 41
    ISSN: 1432-1041
    Keywords: Anti-arrhythmic agents ; myocardial depressants ; beta adrenergic receptor blocking ; agents ventricular arrhythmias
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary The anti-arrhythmic properties of the dextro-isomer of the beta-blocking agent alprenolol have been investigated in 15 patients with different cardiac arrhythmias. The frequency of extrasystoles and other arrhythmias has been expressed quantitatively by counting the total number of arrhythmic episodes from continuous ECG-recordings on magnetic tape. The drug was given as single i.v. injections of 30 mg to 150 mg, or, as i.v. infusions of 0.5 to 3.5 mg/min. After d-alprenolol there was a mean reduction of 95% in the frequency of ventricular extrasystoles in all six patients with this type of arrhythmia. In five of the six patients with atrial fibrillation, the ventricular rate fell considerably, and one of the patients regained sinus rhythm. In six patients with paroxysmal ventricular and supraventricular tachycardias, the arrhythmic attacks were prevented by d-alprenolol. In two cases repeated episodes of ventricular fibrillation were suppressed by d-alprenolol. The drug produced a fall in systolic blood pressure in all patients, ranging from 5% to 46%. Three patients with acute myocardial infarction had symptoms of clinical shock, which disappeared during treatment with i.v. infusion of noradrenaline.
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  • 42
    ISSN: 1432-072X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The composition and synthesis of DNA in synchronous cultures of Chlorella pyrenoidosa strain 211/8b has been investigated. Analytical CsCl density gradient centrifugation gave a homogenous major DNA component with a (G+C) content of 51% and a minor component containing 28% (G+C). The (G+C) contents derived from melting profiles were 2–3% lower. A second minor component with approximately 41% (G+C) content was inferred from banding patterns of labelled DNA in preparative CsCl density gradients. 14C-uracil was readily incorporated into the pyrimidine moieties of the major (nuclear) DNA between the 10th and 18th hour after beginning of the light period, but not at any other time. 14C-uracil incorporation into the minor (satellite) component was low but continuous throughout the whole cell cycle. The incorporation is correlated with an increase in the proportion of satellite DNA from 6% up to 20% during the time when no nuclear DNA replication takes place. The results suggest that different regulatory mechanisms exist for the nuclear and for satellite DNA synthesis.
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  • 43
    ISSN: 1432-072X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Sclerotia of Sclerotinia sclerotiorum (Lib.) D By. were obtained from commercial pea-and bean-cleaning operations or grown on potato-dextrose agar and synthetic glucose-and sucrose-salts agar media. The crude fat (ether extract) content of sclerotia varied from 0.8 to 1.5%. Extraction and fractionation of the lipids followed by gas chromatographic analysis showed that sclerotia from pea cleanings contained one predominant hydrocarbon which was absent from sclerotia produced in the laboratory. Sclerotia from natural sources and grown in the laboratory contained a similar distribution of C18 unsaturated free fatty acids, however, quantitative differences were noted. Palmitic, oleic and linoleic were the major free fatty acids of the laboratory-grown sclerotia while a high proportion of linoleic acid was also found in sclerotia from natural sources. Sclerotia were fractionated into water-soluble and water-insoluble fractions. After acid hydrolysis of the waterinsoluble fraction, both fractions were analyzed for amino acids. Twenty-one compounds, including 2 unknowns, were detected in the soluble fraction. The hydrolyzates contained 19 amino acids, including the same 2 unknowns. Two compounds tentatively identified as ornithine and γ-aminobutyric acid were found only in the water-soluble fraction. The relative amino acid composition of the water-insoluble fraction of sclerotia from various sources was fairly constant but the arginine content decreased on the synthetic media.
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  • 44
    ISSN: 1432-072X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung 1. Struktur und Wachstum von Gallionella ferrunginea in den ersten 6 Std der Entwicklung wurden an einem natürlichen Standort (Ausfluß einer Felddrainage) untersucht. 2. Für die elektronenmikroskopischen Untersuchungen wurde ein Filmbewuchsverfahren benutzt, das weitgehend der von Cholodny (1924) lichtmikroskopisch angewandten Aufwuchstechnik entspricht. 3. Mit dieser Technik, die sich von der anderer Autoren (Beger u. Bringmann, 1953; Vatter u. Wolfe, 1956; Van Iterson, 1958; Balashova, 1967) unterscheidet, war es möglich, vollständig entwickelte, unversehrte, unter natürlichen Bedingungen aufgewachsene Gallionella-Bänder elektronenmikroskopisch abzubilden. 4. Bei nahezu allen beobachteten Aufwuchsbändern war die Band-Ansatzstelle auf der Formvarfolie von zahlreichen mit Eisen inkrustiert erscheinenden, elektronenoptisch dichten, runden Partikeln (ϕ 10–30 mμ) umgeben, die größenordnungsmäßig mit jenen winzigen, vor kurzem von Balashova (1969) in Gallionella-Laborkulturen beobachteten mycoplasmaartigen Körpern übereinstimmen. 5. Mehrfach wurden feine gewundene Einzelfibrillen (ϕ 5–10 mμ) von unterschiedlicher Länge (0,2–3,5 μm) beobachtet, die terminal von winzigen, elektronenoptisch dichten Partikeln (ϕ 40–50 mμ) begrenzt werden. Die Partikel stimmen strukturell und größenordnungsmäßig mit den an den Band-Ansatzstellen beobachteten Körpern überein. Die Fibrillen ähneln strukturell einzelnen Gallionella-Fibrillen mit anhaftenden “Knospen”, die von Balashova (1967) in Gallionella-Bändern beobachtet wurden, die nur aus wenigen Längsfasern bestanden. 6. Die Bandbreite der aus 30–40 Fibrillen bestehenden 2–6 Std-Aufwuchs-bänder betrug 0,3–0,5 μm, die Fibrillenstärke variierte zwischen 2–12 mμ. Verzweigte Gallionella-Bänder wurden auf den 2–6 Std-Präparaten nicht beobachtet. 7. Die durchschnittliche Wachstumsgeschwindigkeit der Gallionella-Bänder betrug in den ersten 6 Std der Entwicklung unter den vorherrschenden Bedingungen (Temperatur: 3°C) ca. 10 μm/Std. 8. Entgegen der Beobachtung, daß endständige Bakterienzellen an elektronen-mikroskopisch untersuchten Gallionella-Bändern nur selten aufzufinden sind (Van Iterson, 1958; Balashova, 1968), wurde festgestellt, daß alle unter natürlichen Bedingungen auf der Formvarfolie aufgewachsenen 2–6 Std-Gallionella-Bänder von einer scheitelständigen Bakterienzelle begrenzt werden. 9. Form und Größe dieser Zelle stimmen mit den von Cholodny (1924) lichtmikroskopisch an den Gallionella-Bändern beobachteten Endzellen überein. Einige Zellen waren allerdings größer als von Cholodny (1924, 1926) und vor kurzem von Balashova (1968) in der Artdiagnose für Gallionella ferruginea angegeben. Die Zellgröße beträgt 0,8–1,8×0,5–0,7 μm. 10. Strukturell unterscheiden sich die beobachteten Endzellen von normalen Bakterienzellen: Sie erscheinen ungewöhnlich transparent, besitzen keine scharf begrenzten Konturen und sind zudem außerordentlich flach. In diesen Strukturmerkmalen gleichen sie den von Vatter u. Wolfe (1956) beobachteten und als “ghost-like” oder “membrane-like” charakterisierten Gallionella-Zellen. Die Zellen besitzen 2–4 elektronenoptisch dichter erscheinende, nicht scharf begrenzte Einschlußkörper im Durchmesser von 90–260 mμ und mehrere Granula mit einem Durchmesser von 30–65 mμ. 11. Seitenzellen, verzweigte Fibrillen, Sporangien in Form von “membrane sacs”, “primordial plasm”, knospende Bakterienzellen an den Band-Fibrillen und zoogloeaartige Wachstumsformen, die von anderen Autoren in Gallionella-Laborkulturen beobachtet wurden, waren auf den jungen unter natürlichen Bedingungen aufgewachsenen 2–6 Std-Bändern nicht vorhanden.
    Notes: Summary 1. Structure and development of Gallionella ferruginea growing under natural conditions in a field-drain-outlet for 2,4 and 6 h were studied. 2. Electron-microscopic preparations of Gallionella developing in this habitat were made by a procedure similar in principle to the cover slip preparation for light-microscopic investigations used by Cholodny (1924), changed according to electron-microscopic investigation-technique. 3. By this technique, which differs from that used by other authors (Beger and Bringmann, 1953; Vatter and Wolfe, 1956; Van Iterson, 1958; Balashova, 1967), it was possible to observe fully developed intact threads of Gallionella ferruginea attached to the formvar-coated platinum grids. 4. The attachment-place of the threads on the formvar membrane was surrounded by numerous round electron opaque particles of submicroscopic size (ϕ 10 to 30 mμ) in dimensions similar to the mycoplasma-like bodies of Gallionella, recently observed by Balashova (1969) in laboratory cultures. 5. Repeatedly, extremely fine (ϕ 5–10 mμ) and wound solitary fibers of varying length (0.2–3.5 μm) were found terminally limited by electron opaque particles of submicroscopic size (40–50 mμ). Size and structure of the particles are similar to those surrounding the attachment-place of the threads. The fibers resemble the individual fibers with buds observed by Balashova (1967) in Gallionella stalks consisting only of a few fibers. 6. Width and ore-coating of the developing 2–6h spirally twisted threads and fibers differ from those figured or described by other authors. The threads consisting of 30–40 fibers have a width of only 0.3–0.5 μm, the diameter of the extremely fine fibers, which seem also mineralized, measured 2–12 mμ. Branching stalks were not observed on the 2–6h-preparations. 7. During the first 6h of development on the formvar membrane the threads grew at an average of 10 μm/h. 8. Contrary to the observation that the majority of Gallionella stalks observed in the electron microscope possessed no cells as described by Van Iterson (1958) and Balashova (1968), it was found that any Gallionella stalk gradually growing on the formvar membrane under natural conditions terminates in an apical bacterial cell. 9. Form and cell size of the apical cells on the developing threads corresponded to Cholodny's description of terminal full grown or divided Gallionella cells; however, some are somewhat larger than those observed by Cholodny (1924, 1926) and Balashova (1968). The cells have a varying size of 0.8–1.8×0.5–0.7 μm. 10. In their structure, the terminal cells on the developing threads differ in some essential features from those observed in normal bacterial cells. The cells were found to be exceptionally transparent, extremely flat and without sharply limited outlines resembling those found by Vatter and Wolfe (1956) and described as “ghost-like” or “membrane-like” Gallionella cells. 2–4 electron opaque “internal bodies” per cell of diameter 90–260 mμ as well as granular structures of diameter 30–65 mμ were observed. 11. The electron micrographs of the 2–6h threads developing under natural conditions did not reveal structures similar to “side-cells”, branched fibers, sporangia-membrane sacs, “primordial plasm”, budding cells on the stalk fibers and zoogleal forms of growth observed by other authors in laboratory cultures of Gallionella.
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  • 45
    ISSN: 1432-072X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung MAK-Säulenchromatographie der Gesamtnucleinsäuren aus autotrophen und gebleichten Zellen von Euglena gracilis, welche für 2 Std mit 32P-Orthophosphat markiert wurden, liefert 6 Komponenten: niedermolekulare RNS (I–III), DNS (IV) und hochmolekulare RNS (V, VI). Das in der DNS-Region eluierte Material konnte mittels Gelfiltration in 32P-DNS, in eine 32P-RNS mit hoher spezifischer Aktivität sowie in 32P-markierte Polyphosphate aufgetrennt werde. Außerdem fanden sich letztere in der 32P-RNS-Fraktion, die relativ fest an die MAK-Säule gebunden bleibt. Eine weitaus bessere Auftrennung der einzelnen RNS-Komponenten gelang mit der Elektrophorese in Polyacrylamid-Gelen. So erschienen in 9.5% Gel 5 Komponenten, darunter die 3 niedermolekularen I–III, welche bei MAK-Chromatographie auftreten. Sie wurden als 4 S Transfer-RNS (I), 5 S ribosomale RNS (II) und 6 S RNS (III) identifiziert. Die hochmolekulare RNS wurde bei Auftrennung in 2,6% Gel in 6 Banden zerlegt. Die der ribosomalen RNS fanden sich als Hauptbanden in der 24 S und 20 S Region des Gels. Aufgrund ihrer Position konnten für die übrigen Komponenten Sedimentationskoeffizienten zwischen 18 S und 9 S berechnet werden. Das elektrophoretische Trennmuster der Gesamtnucleinsäuren aus gebleichten Zellen war sehr ähnlich, wenngleich quantitative Unterschiede zwischen den einzelnen Komponenten bestanden. Bei der Fraktionierung der Nucleinsäuren durch Gel-Elektrophorese im präparativen Maßstab fiel für jede markierte RNS-Komponente genügend Material an, um eine Rechromatographie an MAK und die Bestimmung der Basenzusammensetzung durchzuführen. Außer Transfer-RNS und 5 S RNS wurden 2 Komponenten in 9,5% Gel isoliert, deren Zusammensetzung ribosomaler RNS entsprach. Eine weitere niedermolekulare Komponente wurde als die schnell markierte RNS identifiziert, welche gemeinsam mit der DNS von der MAK-Säule eluiert wird. Die präparative Gel-Elektrophorese der 32P-markierten hochmolekularen RNS in 2,6% Gel lieferte neben mehreren ribosomalen Species auch 32P-RNS mit einer hohen spezifischen Aktivität.
    Notes: Summary MAK column chromatography of total nucleic acids from autotrophic and bleached cells of Euglena gracilis cultured with 32Pi for 2 h resulted in the separation of six labelled components: low molecular RNA (I–III), DNA (IV) and high molecular RNA (V, VI). Gel filtration of the material eluted in the DNA region revealed the presence of 32P-RNA with a high specific activity and of 32P-labelled polyphosphates in addition to 32P-DNA. 32P-polyphosphates were also found among the labelled RNA tenaciously bound to the MAK column. A far better resolution of the RNA components, however, was achieved by polyacrylamide-gel electrophoresis. On a 9.5% gel five main fractions were resolved among which appeared the components I–III isolated by MAK chromatography. They were identified as 4 S transfer RNA (I), 5 S ribosomal RNA (II) and 6 S RNA (III). The high molecular RNA gave rise to six bands when a 2.6% gel was used. From these the ribosomal RNA migrated as two bands in the 24 S and 20 S region of the gel. Based upon these values sedimentation coefficients from 18 S to 9 S were calculated for the others. The electrophoretic pattern of total nucleic acids from bleached cells was rather similar; only quantitative differences were observed. Fractionation of the nucleic acids by polyacrylamide-gel electrophoresis on a preparative scale provided enough material of each labelled RNA component to perform a rechromatography on MAK and to determine the base composition. Besides the 4 S transfer RNA and the 5 S RNA two RNA components with a ribosomal type base composition were isolated on a 9.5% gel. Another one was identified as the rapidly labelled RNA which is eluted with the DNA from the MAK column. Preparative gel electrophoresis of the labelled high molecular RNA (2.6% gel) revealed the presence of several ribosomal species in addition to 32P-RNA components with a high specific activity.
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  • 46
    Electronic Resource
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    Archives of microbiology 75 (1970), S. 67-79 
    ISSN: 1432-072X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The primary and secondary cysts of Saprolegnia ferax and the secondary cysts of Dictyuchus sterile have a two layered wall structure, the outer layer of which bears various types of spines. These spines, and the outer wall layer are derived from preformed structures (bars) found in the cytoplasm prior to encystment. Golgi derived vesicles appear to contribute to the inner layer of the primary cyst wall of S. ferax. The outer surface of the secondary cyst walls of this species has fibrils which are not embedded in matrix material.
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  • 47
    ISSN: 1432-072X
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    Topics: Biology
    Description / Table of Contents: Zusammenfassung Zur Untersuchung der Nicotinsäurebiosynthese werden an wachsenden Kulturen von Mycobacterium bovis Stamm BCG Einbauversuche mit 14C-markierten Precursoren durchgeführt und die spezifischen Inkorporationsraten sowie die 14C-Verteilung der isolierten Nicotinsäure bestimmt. Formiat-(14) und D-Ribose-(U-14C) werden nicht in Nicotinsäure eingebaut. Im Gegensatz zu Befunden anderer Autoren an Clostridium butylicum zeigen Formiat-(14C) und Acetat-(14C) im Rohhomogenat von BCG-Bakterien keinen Einbau in Nicotinsäure und sind als Nicotinsäurevorstufen auszuschließen. Glycerin-(1,3-14C) und Glycerinsäure-(3-14C) gehen bevorzugt in die C-Atome 4, 5 und 6. Das C-Atom 6 der Nicotinsäure entspricht dem C-3 der Glycerinsäure. Somit erfolgt der Einbau der Glycerinsäure nicht über ein symmetrisches Intermediärprodukt. Durch Isotopen verdünnungsanalyse wird Chinolinsäure als Ausscheidungsprodukt von M. bovis Stamm BCG nachgewiesen. Ihre Biosynthese erfolgt in Analogie zur Nicotinsäurebildung aus Aspartat und Glycerin.
    Notes: Summary Biogenesis of nicotinic acid was studied by feeding 14C-labelled precursors in growing cultures of Mycobacterium bovis strain BCG. The incorporation rate as well as the distribution of 14C in the isolated nicotinic acid were determined. Formate-(14C) and D-ribose-(U-14C) were not incorporated into nicotinic acid. In contrast to experiments performed with Clostridium butylicum, crude homogenates of M. bovis strain BCG showed no incorporation of formate-(14C) and acetate-(14C) under the experimental conditions applied and therefore, these compounds should be excluded as possible precursors. Glycerol-(1,3-14C) and glyceric acid-(3-14C) are incorporated into positions 4, 5 and 6, as expected. The carbon atom 6 of nicotinic acid was almost exclusively derived from C-3 of glyceric acid. Incorporation of glyceric acid therefore does not follow through a symmetrical intermediate. By isotope dilution technique quinolinic acid has been found in the culture medium indicating to be an excretary product of M. bovis strain BCG. Its biosynthesis occurs, in analogy to nicotinic acid formation, from aspartate and glycerol.
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  • 48
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    Archives of microbiology 71 (1970), S. 235-244 
    ISSN: 1432-072X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary 1. The ability to decompose choline is widespread among aerobic microorganisms since representatives of the genera Agrobacterium, Arthrobacter, Micrococcus, Pseudomonas, Rhizobium, and Streptomyces and a large number of coryneform bacteria were found to grow with choline as the sole C- and N-source. 2. Almost all the coryneforms isolated from soil and dairy waste activated sludge displayed this ability in contrast to those isolated from cheese and, be it to a less extent, those from the phyllosphere. The significance of choline utilization in the taxonomy of coryneform bacteria is discussed. 3. All the choline-utilizing bacteria tested were found to be able to grow with betaine, N,N-dimethylglycine, or sarcosine as the sole C- and N-source. Choline-grown cells, as contrasted to those grown with yeast extract and glucose, of Pseudomonas fluorescens and Arthrobacter S3 respired the latter three compounds at a rate similar to that of choline. 4. About 30% of the 50 choline-utilizing coryneform bacteria tested grew also with N,N-dimethylethanolamine and N-monomethylethanolamine. Choline-grown cells, in contrast to those grown with yeast extract and glucose, of a representative of this group, Arthrobacter S3, also respired these two compounds at a rate somewhat lower than that of choline.
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  • 49
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    Archives of microbiology 71 (1970), S. 220-225 
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    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Continuous infusion of D-glucose, 10-8–10-6 mole/min/g fresh weight, to anaerobic Saccharomyces carlsbergensis cell suspensions induces sustained oscillations of intracellular NADH. Under these conditions the metabolic flux is 100 times less than that after singular addition of an excess of D-glucose. The infused D-glucose is being catabolized except for the periods of rising NADH, where an overshoot in D-glucose concentration occurs shortly before NADH peaks. The oscillatory characteristics under the two conditions are compared. Oscillatory fluctuations in metabolic concentrations are very useful tools in studies on metabolic control in flux systems. But unfortunately rapid damping is observed in yeast suspensions. The infusion technique, as proposed by Sel'Kov (personal communication) was found useful with glycolysing yeast extract (Hess and Boiteux, 1968). Since the cell-free extract of yeast cells varies from day to day with respect to its metabolic and control features, we decided to apply infusion technique to suspension of yeast cells.
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  • 50
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    Archives of microbiology 76 (1970), S. 1-1 
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    Topics: Biology
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  • 51
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    Topics: Biology
    Notes: Summary Conditions for cultivating two extremely thermophilic bacteria, isolated from the hot springs of Yellowstone National Park, are described. One of these strains, Thermus aquaticus, can be grown on either succinate or pyruvate as the best substrates at 78° C. Acetate, glucose, and sucrose can also be utilized at this temperature. The temperature optimum was found to be 70° C, but the bacterium can be adapted to grow on succinate or pyruvate at 80° C. The other strain, YT-G has its growth optimum at 80° C and the maximum temperature was found to be 84° C. At this temperature pyruvate is the only substrate which gives good results, while glucose cannot be used as a carbon source. At 70° C, however, the yields obtained with glucose as a substrate are better than those with pyruvate at 80° C. Experiments with C14-labelled glucose have shown that the inability to utilize glucose at 80° C is not due to an inactivation of the initial steps of the glycolytic pathway. Phosphorylated sugars and a compound corresponding to α-glycerophosphate were found to be formed, the latter being accumulated as a side product of normal glycolysis. The enzymes leading to this product, and those which are involved in the conversion of pyruvate were found to be functioning at 80° C, while intermediate enzymes of the glycolytic pathway are assumed to be less heat resistant, thus blocking the utilization of glucose at this temperature. The ability of strain YT-G to grow on glucose is, however, promptly resumed if the temperature is lowered. Lysozyme treatment was found to lead to a complete conversion of T. aquaticus cells to spheroplast while cells of strain YT-G are only slightly altered by this procedure.
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  • 52
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    Topics: Biology
    Notes: Summary The pigments of two strains of extremely thermo-resistant bacteria were extracted and examined spectrophotometrically. Both strains contain α-carotene as the main pigment according to the spectral characteristics of the pigment in various solvents. According to quantitative data Thermus aquaticus contains more than one hundred times as much of the pigment than is found in strain YT-G, representing almost 80% of the total lipid. The carotene of strain YT-G is destroyed by hot saponification, while that of T. aquaticus resists that procedure without alterations. T. aquaticus contains a small amount of a second pigment with absorption maxima at 370, 400 and 420 mμ. Solubilization of the membrane of spheroplasts derived from acetate-C14-labelled cells of T. aquaticus, followed by separation of the crude membrane fraction, showed that about 50% of the C14 is associated with the membrane fraction. More than 90% of the C14 is recovered in the yellow supernatant of the acetone-extracted crude membrane fraction, showing that a rapid incorporation of the label into the pigment occurs. The assumption that the pigment is associated with the membrane is supported by submicroscopical observations: T. aquaticus has a well-defined cytoplasmic membrane, and on top of this a sandwiched layer, which is embedded in a very electron-dense material, that we assume to consist of the pigment. Strain YT-G which contains only minute quantities of the same pigment, does not possess this kind of an outer membrane, but shows only a cytoplasmic membrane envelopped by the cell wall.
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  • 53
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    Archives of microbiology 76 (1970), S. 47-50 
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    Topics: Biology
    Notes: Summary A complex system of growth inhibition is present in the green algae (Volvocaceae). Inhibitors are found in the culture filtrates of some genera which limit their own growth (autoinhibition) while others in the family produce inhibitors which check the growth of other genera (heteroinhibition). These inhibitors are destroyed by autoclaving.
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  • 54
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    Topics: Biology
    Notes: Summary Enzyme activities have been measured and compared at several stages of the development of Neurospora crassa i.e. from free conidia (inoculum) to conidiated mycelia grown on sucrose versus acetate (poor versus highly conidiogenous) media. Glucose-6-phosphate dehydrogenase (G-6-PDH) and NADP nucleotidase (NADPase) show inverse activity-time curves, both on sucrose and acetate media. G-6-PDH has its higher activity at the preconidiating stage while NADPase progressively increases to reach its maximal value in the mature conidia. Malate dehydrogenase (MDH) has a higher activity in extracts from acetate compared to sucrose cultures; in both conditions, maximal MDH activity corresponds with the initiation of conidiation. Malate synthetase (MS) has a delayed activity which is much higher in acetate extracts. Succinate dehydrogenase (SDH) is more active in sucrose than acetate extract with a sharp activity peak just preceding conidiation proper. Isozymes of G-6-PDH and MDH, as well as total soluble proteins from extracts of sucrose versus acetate cultures have been compared after their separation on polyacrylamide columns.
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  • 55
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    Topics: Biology
    Description / Table of Contents: Zusammenfassung Die Konzentration an Acetaldehyd im Medium während der anaeroben Vergärung von Glucose durch Saccharomyces cerevisiae weist in der logarithmischen Wachstumsphase die höchsten Werte auf. Die Induktion der Pyruvatdecarboxylase durch Glucose fördert die Akkumulation von Acetaldehyd, der ins Medium diffundiert. Hefestämme, die unterschiedlich viel Acetaldehyd bilden, unterscheiden sich in ihren Pyruvatdecarboxylaseaktivitäten. Diese engen Beziehungen zwischen Pyruvatdecarboxylase und Acetaldehydproduktion deuten auf die Kontrollfunktion der Pyruvatdecarboxylase bei der Acetaldehydakkumulation hin. Höhere Aktivitäten der Alkoholdehydrogenase verringern die Acetaldehydakkumulation, wodurch sich ein Hinweis auf die Rolle dieses Enzyms bei der Regulation der Acetaldehydkonzentration ergibt.
    Notes: Summary During fermentation of glucose by Saccharomyces cerevisiae maximum acetaldehyde production coincides with maximum pyruvate decarboxylase activity in the logarithmic phase of growth. The stimulation of this enzyme by high glucose levels leads to an increased formation of acetaldehyde, which diffuses into the medium. Yeast strains, which produce varying amounts of acetaldehyde also exhibited varying pyruvate decarboxylase activities. The close relationship between pyruvate decarboxylase activity and acetaldehyde production suggests a control function of the enzyme in acetaldehyde accumulation. Apart from pyruvate decarboxylase higher activities of alcohol dehydrogenase show the reversed influence on aldehyde concentration, thus demonstrating the role of alcohol dehydrogenase in aldehyde production.
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  • 56
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    Topics: Biology
    Notes: Summary The light-induced formation of NADH by whole cells of Rhodopseudomonas spheroides has been followed fluorimetrically and found to lag slightly behind cytochrome c oxidation. The uncoupler, FCCP1, abolished NADH formation which was also inhibited by HOQNO1. Electron flow from NADH to oxygen or cytochrome c was inhibited in chromatophores of R. spheroides by HOQNO, antimycin A and rotenone. From the known properties of the inhibitors used it is deduced that NADH formation in the light is dependent upon reversed electron flow. No light-induced formation of NAD(P)H by whole cells or chromatophores of Chlorobium thiosulfatophilum was detected either fluorimetrically or by extraction followed by enzymic assay although cytochrome c oxidation was extensive in whole cells. Extracts of C. thiosulfatophilum catalysed the rapid reduction of endogenous or mammalian cytochrome c; unlike R. spheroides this activity was found almost entirely in the soluble fraction and was insensitive to HOQNO, antimycin A and rotenone. No cytochrome b was detected in C. thiosulfatophilum by difference spectroscopy of pyridine haemochromes of acetone powders. The K m for NADH of NADH-cytochrome c reductase in both organisms was about 3 μmol; the reductase was inhibited by NAD. The rates of NADPH-cytochrome c reductase in R. spheroides particles were too low for K m determination; for C. thiosulfatophilum particles the K m for NADPH was about 300 μmol. The addition of NADH to soluble extracts of either organism caused the reduction of endogenous flavin that was reoxidised by ferricyanide. The NADH-cytochrome c reductase of C. thiosulfatophilum was not separated from ferredoxin on a DEAE column. It is concluded that in C. thiosulfatophilum the formation of NADH in an energy-linked reaction is unlikely; the possibility of a cyclic electron flow involving chlorophyll, ferredoxin, flavoprotein and cytochrome c is discussed.
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  • 57
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    Notes: Summary Phenethyl alcohol (PEA) can activate dormant ascospores of Neurospora. Between 4 to 8×10-8 M PEA solutions induce germination of ascospores of N. crassa and N. tetrasperma equal to or higher than that of those activated by heat. This PEA effect is significantly greater than that of related chemicals and of other compounds known to induce fermentative metabolism. Influences of duration of exposure, sporal age, respiratory inhibitors and alcohol dehydrogenase activity have been studied in their relationship with PEA activation of dormant ascospores.
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  • 58
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    Archives of microbiology 72 (1970), S. 106-110 
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    Description / Table of Contents: Zusammenfassung Am Beispiel der unter kontinuierlicher Substratzufuhr erfolgenden Äthanol-Synthese in Hefe (Saccharomyces carlsbergensis) konnte gezeigt werden, daß unabhängig von der exogenen Substratmenge der Speicherstoffwechsel einer linearen Regelfunktion unterliegt. Das Verhältnis zwischen Äthanolbildung aus exogenem und endogenem Material ist derart ausbalanciert, daß die Gesamtbilanz erhalten bleibt, nach der 50–60% der zugeführten Glucosemenge im Äthanol wiederzufinden sind.
    Notes: Summary The synthesis of ethanol under continuous infusion of d-glucose to anaerobic Saccharomyces carlsbergensis demonstrates very distinctly that turnover of the carbohydrate pool has the characteristics of a linear regulation, independent of the exogenous substrate amounts. The relation between glycolysis and pool turnover is balanced exctly so that 50–60% of glucose infused will be synthesized to ethanol.
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  • 59
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    Topics: Biology
    Description / Table of Contents: Zusammenfassung Die Pigmente der Blau- und Rotalgen wurden nach den bei Hager u. stransky (1970a) angegebenen Methoden identifiziert und ihre Mengen bestimmt. 1. In der Primärcarotinoid-Ausstattung der Blaualgen sind in erheblichen Mengenanteilen Ketocarotinoide enthalten, welche bei anderen Algengruppen nur als Sekundärcarotinoide zu finden sind. Sie können allerdings ähnlich wie bei bestimmten Grünalgen unter Stickstoffmangel derart vermehrt werden, daß sie eine Rotfärbung solcher Kulturen hervorrufen. 2. Die Blaualgen besitzen im Gegensatz zu den anderen Algen-Abteilungen auch monocyclische Carotinoid-Glycoside (Myxoxanthophyll), welche neben acyclischen Carotinoiden für die Bakterien typisch sind. 3. Die Ketocarotinoide der Blaualgen sind bevorzugt an C4 und C4′ substituiert. Derartige Carotinoide sind charakteristisch für eine große Anzahl von Tieren, insbesondere für Vertreter der Anostracen und Cladoceren (Lee, 1966; Lee et al., 1967; Czeczuga u. Czerpak, 1966; Gilchrist, 1968). 4. Die Blaualgen sind nicht zur Synthese von α-Carotin und seinen Derivaten befähigt. 5. Einige Blaualgen können die hier erstmals beschriebenen Allen-Carotinoide Caloxanthin (3,3′-Dihydroxy-5-Hydro-7-Dehydro-β-Carotin) und Nostoxanthin (3,3′-Dihydroxy-5,5′-Dihydro-7,7′-Didehydro-β-Carotin) bilden. 6. Die untersuchten Rotalgen und Blaualgen besitzen keine Carotinoid-Epoxide. Entsprechend dieser Tatsache konnten hier auch keine lichtinduzierten Xanthophyll-Umwandlungen beobachtet werden. 7. Durch kurzzeitige Belichtung können aber reversible Änderungen im Absorptions-Spektrum von Phycoerythrinen erfolgen.
    Notes: Summary The pigments of some blue-green and red algae have been identified and quantitatively determined by methods discussed in Hager and Stransky (1970a). 1. a great deal of the primary carotenoids of the blue-green algae are ketocarotenoids, which in other groups of algae are present as secondary carotenoids. Similar to certain green algae the amount of these pigments is increased during nitrogen starvation, causing a red colouring of such cultures. 2. In contrast to other divisions of algae the blue-green algae contain also monocyclic carotenoid glycosides (myxoxanthophyll), which besides acyclic carotenoids are typical for bacteria. 3. The keto-carotenoids of the blue-green algae are mainly substituted at C4 and C4′. Such carotenoids are characteristic for a great deal of animals, especially for members of Anostraca and Cladocera (Lee, 1966; Lee et al., 1967; Czeczuga and Czerpak, 1966; Gilchrist, 1968). 4. The blue-green algae are not able to synthesize α-carotene and its derivatives. 5. Some blue-green algae can form allenic carotenoids, which have been described for the first time; they have been named caloxanthin (3,3′-dihydroxy-5-hydro-7-dehydro-β-carotene), and nostoxanthin(3,3′-dihydroxy-5,5′-dihydro-7,7′-didehydro-β-carotene). 6. The investigated red and blue-green algae contain no carotenoid epoxides. Due to this fact no light induced xanthophyll interconversions are detectable. 7. However, by short illumination a reversible change in the absorption spectrum of phycoerythrins takes place.
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  • 60
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    Notes: Summary Hyphal walls of Apodachlya sp. (Leptomitales) gave a positive reaction when tested cytochemically for chitin. The color reaction indicative of the presence of chitin developed uniformly throughout the walls, but did not appear in the numerous cellulin granules found in this fungus. Chitin and cellulose fractions were prepared from chemically isolated walls and identified by X-ray diffraction.
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  • 61
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    Notes: Summary A strain of Candida tropicalis has been isolated from soil using a mineral medium that contained n-tetradecane as sole source of carbon. This strain has been studied and variants have been isolated. In contrast to the original strain in which hydrocarbon degradation is linked to enzymatic induction mechanisms, the “variant” 101 behaves like a constitutive strain for n-tetradecane.
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  • 62
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    Topics: Biology
    Notes: Summary The particulate fraction in cell-free extracts of three Chlorobium strains was examined. It contains two structural components: membrane fragments and chlorobium vesicles. These two components have been separated, and certain of their properties compared. Both consist largely of lipid and protein. The lipids of the membrane fraction are predominantly phospholipids, but include a glycolipid which contains galactose, rhamnose and an unidentified sugar. The vesicles are highly enriched in bacteriochlorophyll, and contain large amounts of a monogalactosyl diglyceride; their content of phospholipid is low. All the succinic and malic dehydrogenase activity of the particulate fraction is located in the membranes, whereas NADH- and NADPH-linked dye reductases occur in both membranes and vesicles. The vesicles in crude extracts are unstable upon storage; they rapidly lose their characteristic structure, accompanied by a destruction of bacteriochlorophyll. These changes can be prevented by brief treatment of extracts with glutaraldehyde. Many of the isolated vesicles contain from 10 to 25 regular intravesicular structures, which are about 10 nm wide and circular, with a central hole 3 nm in diameter.
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  • 63
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    Topics: Biology
    Notes: Summary 1. Zoospore mother cells in Bulbochaete are shown to be surrounded by a structure interposed between the plasmalemma and the cell wall which is interpreted as the precursor of the vesicle which temporarily surrounds the zoospore on its release. 2. As this vesicle precursor matures it thickens apically to form a ring consisting of a core and two layers. These two layers envelope the young zoospore as its vesicle. Later a space, referred to as the sub-ring, develops within the middle layer of the ring. 3. Histochemical tests indicate that the vesicle precursor and ring are highly proteinaceous with a small carbohydrate component. 4. Dehiscence is apical and thought to be assisted by the apical ring. Upon release of the zoospore, its vesicle is essentially composed of the inner layer of its precursor.
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  • 64
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    Topics: Biology
    Description / Table of Contents: Zusammenfassung Isolierungsversuche an den hefeartigen Endosymbionten von 17 Anobiidenarten hatten nur in 5 Fällen Erfolg, zwei weitere Arten leben nicht in Symbiose. — Der Wirkstoffbedarf der isolierten Stämme wurde untersucht (Tab. 1). — Alle Stämme verwerteten Ammonsulfat und Harnsäure als N-Quellen, während Kaliumnitrat nur von den Symbionten von Ernobius mollis, Harnstoff von diesen und denen von Xestobium plumbeum assimiliert wurden. — Die Symbionten scheiden Aminosäuren in ihre Umgebung aus (Tab. 2). — Im Kultursubstrat des Symbioten von Stegobium paniceum wurden Lactoflavin, Pyridoxin, Pantothensäure und Folsäure nachgewiesen. — Serologische Untersuchungen zeigten, daß die Symbionten in 3 Gruppen zerfallen; eine Verwandtschaft zwischen Symbiotaphrina kochi und Taphrina purpurascens besteht nicht. — Die taxonomischen Merkmale der vorliegenden Stämme werden beschrieben. Zwei Symbionten gehören bisher unbekannten Arten an. — Die Befunde werden im Hinblick auf die Situation der Symbionten im Wirtsorganismus diskutiert.
    Notes: Summary Isolation of yeastlike endosymbiotes of Anobiid beetles was successful in 5 from 17 species. Two further species proved not to live in symbiosis. — The requirement for growth promoting substances was studied in the isolated strains (Tab. 1). — Ammonium sulphate and uric acid were used by all strains, urea by the symbiotes of Xestobium plumbeum and Ernobius mollis, potassium nitrate only by the latter. — Excretion of amino acids was studied (Tab. 2). — Excretion of lactoflavine, pyridoxine, pantothenic acid and folic acid was shown in the symbiote of Stegobium paniceum. — With serological methods the studied strains could be divided into three groups. No correlations exist between Symbiotaphrina kochi and Taphrina purpurascens. — The physiological characteristica with taxonomical value are described; two symbiotes proved to be novae species. — The results are discussed with regard to the situation of the symbiotic microorganisms in the host.
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  • 65
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    Archives of microbiology 72 (1970), S. 238-251 
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    Topics: Biology
    Description / Table of Contents: Zusammenfassung Drei thermophile und ein mesophiler Bacillus sphaericus-Stamm wurden gefriergeätzt und ihre Feinstruktur verglichen. Mit Ausnahme eines thermophilen Stammes konnte bei allen untersuchten Organismen eine aus 13 nm großen Einheiten aufgebaute, rechtwinkelig geordnete Zellwandoberflächenstruktur nachgewiesen werden. Die Zellwand ließ sich bei sämtlichen Stämmen zweischichtig aufspalten. An ihren Querbrüchen traten 10–20 nm dicke Fibrillen auf, die als Subeinheiten der Zellwand gedeutet werden. Das Gefrierätzbild der Cytoplasmamembran läßt eine Deutung im Sinne einer teilweisen Aufspaltung längs einer zentralen Ebene zu. An aufgebrochenen Reservestoffgranula wurden hornartige Artefakte dargestellt, deren Entstehung teilweise auf eine schlagartige Expansion eines komprimierten, streng abgrenzbaren zentralen Teiles zurückgeführt wird.
    Notes: Summary The fine structures of three thermophilic and one mesophilic strain of Bacillus sphaericus have been compared by means of freeze etching. With the exception of one thermophilic strain, all strains had a rectangular cell wall surface structure consisting of 13 nm units. With all strains it was possible to split the cell wall into two layers. On its cross fractures 10–20 nm thick fibrils could be observed, presumably subunits of the cell wall. The image yielded by the freeze etched cytoplasmic membrane can be interpreted as due to partial cleaving along a central plane. The formation of hornlike artefacts rising from cross-fractured storage granules is explained partially by a sudden expansion of a compressed central part.
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  • 66
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    Archives of microbiology 72 (1970), S. 252-259 
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    Topics: Biology
    Notes: Summary A biphasic dependence of the exponential growth rate on the glucose concentration of the medium was observed in batch culture experiments for a strain of S. cerevisiae and one of its petit mutants. The data can be fitted to an equation of the Michaelis-Menten type with two sets of values of the growth parameters; the switch-over occurs at a glucose concentration of 4 mM. Another petit mutant did not show the biphasic character. Regulation of the energy metabolism in relation to the cell cycle is discussed. It is suggested that the observed shift in the growth parameters may be due to a change in the control point of glycolysis from phosphofructokinase to pyruvate kinase at higher glucose concentrations. This could reduce the duration of the G1 phase by permitting a faster synthesis of reserve carbohydrates required as intracellular energy reservoirs for DNA synthesis.
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  • 67
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    Topics: Biology
    Description / Table of Contents: Zusammenfassung Uredosporen von Puccinia graminis wurden auf einem flüssigen Medium durch Zusatz von Cumarin zur Keimung gebracht. Wir verfolgten die Veränderungen der Enzymaktivitäten von Glucose-6-phosphat-Dehydrogenase, Phosphogluconat-Dehydrogenase und von Glucose-6-phosphat-Isomerase in Abhängigkeit von der Inkubationszeit. Im Gegensatz zu den Enzymen keimender Sporen saprophytischer Pilze nehmen die Gesamtaktivitäten aller drei Enzyme im Anschluß an einen kurzen Anstieg innerhalb der ersten Stunde bzw. der ersten 2 Std wieder ab. Nach 12 Std findet man für Phosphogluconat-Dehydrogenase und für Glucose-6-phosphat-Isomerase niedrigere Werte als vor Beginn der Inkubation. Die spezifischen Aktivitäten von Phosphogluconat-Dehydrogenase und Glucose-6-phosphat-Isomerase bleiben nahezu konstant. Dagegen nimmt die spezifische Aktivität von Glucose-6-phosphat-Dehydrogenase zu. Die in den Uredosporen von Puccinia graminis gefundenen spezifischen Enzymaktivitäten sind wesentlich höher als die in den Sporen saprophytischer Pilze.
    Notes: Summary Uredospores of Puccinia graminis were germinated on a liquid medium containing coumarin. We followed changes in enzyme activities of glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase and glucose-6-phosphate isomerase as a function of time of incubation. Contrary to the enzymes in germinating spores of saprophytic fungi the total activities of all three enzymes declined clearly after a short lasting rise during the first or the first 2 h of incubation. 12 h after the beginning of the experiment the total activities of 6-phosphogluconate dehydrogenase and of glucose-6-phosphate isomerase had declined even below the level of not incubated spores. The specific acitivities of 6-phosphogluconate dehydrogenase and glucose-6-phosphate isomerase stayed nearly constant during the time of the experiment, whereas the specific activity of 6-phosphogluconate dehydrogenase increased. The specific activities of these enzymes found in uredospores of Puccinia graminis are considerably higher compared to those found in saprophytic fungi.
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  • 68
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    Archives of microbiology 72 (1970), S. 297-307 
    ISSN: 1432-072X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Among the indole compounds formed when tryptophan 2-14C is metabolized by Rhizobium, indole-3-lactic acid (ILA) is specially studied. In the course of experiments carried out in the culture medium of growing Rhizobium and in suspensions of washed bacterial cells the amount of ILA formed is compared with that of indole-3-acetic acid (IAA) occurring simulataneously. The formation of ILA and that of IAA directly depend on a transamination reaction. A large quantity of ILA is present in suspensions of washed bacterial cells. When ILA alone, as precursor, is incubated with Rhizobium, several products are identified: IAA, indole-3-acetaldehyde and tryptophol. Tryptophan is also detected in the aqueous fraction and is labelled when ILA 2-14C is used. The pathway of this metabolism are discussed and a general scheme is suggested.
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  • 69
    ISSN: 1432-072X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Representatives of the species of the genus Bifidobacterium isolated from bovine rumen, intestinal content of honey bees and pig feces were studied for their deoxyribonucleic acid similarities with DNA-DNA filter hybridization-competition experiments. The species were: B. asteroides, B. indicum and B. coryneforme from honey bees; B. ruminale and B. globosum from rumen; B. suis from pig feces; Mitsuoka's species B. thermophilum and B. pseudolongum. Strains of B. bifidum, B. infantis, B. longum and B. breve from human sources were included in some comparative experiments. The group of bacteria investigated is largely heterogeneous: virtually no homology exists among the species from rumen and pig feces; the species or types from bees, although unrelated with rumen and pig types, share with these a significant portion of the genome; the competitor DNA's from human strains did not at all react with any of the homologous systems. The annealing reaction was carried out under stringent conditions to ensure against mismatching of nucleotide sequences (70°C in Denhardt's reactive mixture). The separation within the genus Bifidobacterium of several specific entities is fully substantiated.
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  • 70
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    Archives of microbiology 72 (1970), S. 267-296 
    ISSN: 1432-072X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung 1. Die Laccase I des Wildstammes von Podospora anserina wurde nach einer verbesserten Methode gereinigt. Dadurch konnten Ausbeute und spezifische Aktivität des Enzyms gesteigert werden. Die Stabilität nahm dagegen ab. 2. Das Verhalten der frisch gereinigten Laccase I bei der Chromatographie an Hydroxylapatit, in der Ultrazentrifuge und in der Disc-Elektrophorese spricht für deren molekulare Einheitlichkeit. 3. Die katalytischen, elektrophoretischen, spektralen und molekularen Eigenschaften sowie die Zusammensetzung der Laccase I wurden untersucht. Sie besitzt ein doppeltes pH-Optimum (pH 5,5 und 7,5), der isoelektrische Punkt liegt bei pH 4,9; sie wird durch Natriumazid reversibel gehemmt (K i =1.9·10-6 M), die Absorptionsmaxima liegen bei 280 und 610 nm. Der Stickstoffgehalt beträgt 13,6%, der Kupfergehalt 0,3%, der Kohlenhydratgehalt 23% der Trockensubstanz. Im Kohlenhydratanteil wurden Hexosamin, Mannose, Glucose und Galactose nachgewiesen. Folgende molekulare Daten wurden ermittelt: Sedimentationskonstante s 20, ω 0 =14,47·10-13 sec, Diffusionskonstante D 20, ω 0 =3,06·10-7 cm2/sec, partielles spezifisches Volumen=0,701 ml/g, Verhältnis der Reibungskoeffizienten f/f 0=1,46. Das Molekulargewicht liegt bei 390.000 (Sedimentation, Diffusion); dies Ergebnis wird bestätigt durch ein mit Gleichgewichtsedimentation zu 383.000 ermitteltes Molekulargewicht. Ein Laccase-I-Molekül enthält somit etwa 18 Kupferatome. 4. Durch veränderte Anzuchtbedingungen des Wildstamm-Mycels (pH der Nährlösung unter 5) kann das Laccasespektrum einer bestimmten Mutante phänokopiert werden. 5. Die Laccase kommt in verschiedenen Polymerisationsstufen vor. Aus den gewonnenen Sedimentationskonstanten läßt sich je nach Versuchsbedingungen sowohl Aggregation zu einem Dimer folgern als auch Dissoziation in 4, möglicherweise 5 aktive Untereinheiten, die nochmals in Hälften zerfallen können. 6. Die Beziehungen der Laccase I des Wildtyps und ihrer verschiedenen Polymerisationsstufen zu den Mutanten-Laccasen werden diskutiert.
    Notes: Summary 0616 04 1. By using an improved method for purification of the laccase I of the wild type of Podospora anserina, yield and specific activity of this enzyme have been increased, whereas its stability decreased. 2. Freshly prepared laccase I seems to be homogeneous, according to its behavior in hydroxylapatite-chromatography, in sedimentation-analysis and in disc-electrophoresis. 3. The catalytic, electrophoretic, spectral and molecular properties and the carbohydrate-composition of laccase I have been investigated. Laccase I exhibits a double-pH-optimum for its reaction with dopa (at pH 5.5 and 7.5), the isoelectric point being at pH 4.9. The enzyme is reversibly inhibited by sodium azide (K i =1.9×10-6 M) and has absorption-maxima at 280 and 610 nm. The content of nitrogen, copper and carbohydrate is 13.6%, 0.3% and 23% of the dry weight, respectively. Hexosamine, mannose, glucose and galactose have been found in the carbohydrate moiety of the enzyme. The following molecular data were determined: sedimentation coefficient s 20, ω 0 =14.47×10-13 sec, diffusion coefficient D 20, ω 0 =3.06×10-7 cm2/sec, partial specific volume=0.701 ml/g, ratio of the frictional coefficient f/f 0=1.46. The molecular weight M s ,D (sedimentation and diffusion) is 390,000. This has been substantiated by finding a molecular weight M ω of 383,000 using equilibrium sedimentation. One molecule of laccase I contains therefore about 18 atoms of copper. 4. The laccase spectrum of a certain mutant strain is phenocopied if the wild type mycelium is grown in a medium of pH 5 or below. 5. The laccase occurs at different degrees of polymerisation. The respective sedimentation coefficients indicate that, depending on experimental conditions, aggregation to a dimer or dissociation into 4, perhaps 5 subunits, can occur. These subunits can be further split into halves. 6. The relation of the multiple forms of laccase I of the wild type to the laccases of some mutants of this fungus is discussed.
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  • 71
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    Archives of microbiology 72 (1970), S. 326-332 
    ISSN: 1432-072X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Field observations of the natural habitats, the temperature maximum for 14CO2 incorporation of natural populations, and the temperature maximum for the growth of cultures of Cyanidium caldarium indicate that the upper temperature limit for C. caldarium is 55–60°C. These results are not compatible with the description of C. caldarium as an extreme thermophile.
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