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  • 1
    ISSN: 1432-119X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Die Akriflavin-Feulgen-Färbung (Böhm und Sprenger, 1968) und die Ethidiumbromid-Fluorochromierung nach vorausgehender Pepsinbehandlung (Göhde et al., 1971) ergeben an Leberzellausstrich-Präparaten weitgehend gleichartige DNS-Häufigkeitsverteilungen. Bei der zeitlich aufwendigen (220 min) Akriflavin-Färbung ist eine optimale Darstellung der Zellmorphologie und eine jahrelange Archivierung der Ausstrichpräparate möglich. Die rasch durchführbare Ethidiumbromid-Färbung (70 min) bietet nur nach schwerer Alteration der Zellmorphologie durch die vorausgehende Pepsinbehandlung eine selektive Darstellung der DNS. Eine Archivierung von Ausstrichpräparaten ist nur für 2 Tage möglich. Die schwere Alteration der Zellmorphologie ist besonders bei durchflußphotometrischen Prescreeninguntersuchungen in der gynäkologischen Krebsvorsorge nachteilig. Zellpopulationen, die zu einer zytophotometrischen Verdachtsdiagnose geführt haben, sind durch Verlust des Zytoplasmas und der Kernstruktur einer konventionellen morphologischen Diagnostik nicht mehr zugängig.
    Notes: Summary Acriflavine-Feulgen (Böhm und Sprenger, 1968) and ethidiumbromide fluorescence after previous pepsin digestion (Göhde et al., 1971) yield corresponding DNA distribution patterns when applied to liver smears. With the time-consuming acriflavine staining (220 min) the cellular morphology is best preserved and the stained specimen may be stored for long periods. The rapidly obtainable ethidiumbromide staining (70 min) results in a selective fluorescence of DNA only after heavy alteration of the cellular morphology by pepsin digestion. Storage of the material is only possible for two days. The heavily altered cellular morphology, however, is rather unfavorable for prescreening in automated cytology. Specimens that were found to be suspicious are no longer suitable for conventional cytological diagnosis, because they have lost their cytoplasm and nuclear chromatin structure.
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  • 2
    ISSN: 1432-119X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Beim Vergleich des Feulgen-Farbgehaltes verschiedener Zellkerne (Leberzellen, Lymphozyten, Granulozyten und Spermien) traten nach Alkoholfixierung Abweichungen der gemessenen Feulgen-Werte von den nach dem Gesetz von der DNS- Konstanz zu erwartenden DNS-Gehalt dieser Kerne auf. Verglichen mit den Feulgen-Werten der diploiden Leberzellkerne ergaben Lympho- und Granulozyten bei allen Hydrolysezeiten zu niedrige (bis zu minus 20%), haploide Spermien im postmaximalen Hydrolysebereich zu hohe Feulgen-Werte (z. T. sogar höhere Werte als die diploiden Zellkerne). Innerhalb desselben Zelltypes wurden dagegen, auch beim Vergleich der verschiedenen Ploidiestufen der Leberkerne, keine Differenzen festgestellt. Da die an Leukozyten und Spermien beobachteten Abweichungen nach Methanol-Formalin-Eisessig-Fixierung nicht mehr auftraten und auch durch UV-absorptionscytophotometrische Messungen nicht bestätigt werden konnten, muß man annehmen, daß es sich um Proportionalitätsfehler handelt, die auf Hydrolyseunterschieden beruhen. Für die quantitative Feulgen-Cytophotometrie scheint daher die Methanol-Formalin-Eisessig-Fixierung besser geeignet zu sein als die Alkoholfixierung, bei deren Verwendung es leicht zu Proportionalitätsfehlern während der Feulgen-Hydrolyse kommen kann.
    Notes: Summary Comparing the Feulgen dye-content of different nuclei (liver cells, lymphocytes, granulocytes and sperms) after alcohol-fixation deviations were found between the measured Feulgen values and the DNA-content to be expected from the DNA-constancy law. The Feulgen values of lymphocytes and granulocytes proved to be lower (up to minus 20%) than those of diploid liver nuclei at all hydrolysis times, while in the postmaximal range of hydrolysis the values of the haploid sperms were too high (even higher than those of the diploid nuclei). Such differences did not appear when nuclei of the same cell type in different DNA- ploidy classes (liver nuclei) were compared. Those deviations of leucocytes and sperms were no longer found after fixation in methanol-formalin-glacial acetic acid and, in addition, could not be confirmed by UV-absorption measurements. For that reason we suppose them to be due to proportionality errors caused by variations in the hydrolytic behaviour of the different nucleoproteins. Thus fixation in methanol-formalin-glacial acetic acid seems to be more suitable for quantitative Feulgen measurements than alcohol-fixation, which may easily give rise to proportionality errors during Feulgen hydrolysis. Moreover, to avoid any false interpretation of Feulgen data we should suggest controll measurements using another independent method (f. e. UV-absorption), or — if this is impossible — to check the Feulgen values after different fixations and variant hydrolysis times (premaximal, maximal, postmaximal).
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  • 3
    ISSN: 1432-0711
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
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  • 4
    ISSN: 1432-0711
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
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  • 5
    ISSN: 1591-9528
    Keywords: Skin wound ; Total body X-irradiation ; Plasma corticosterone ; Hautwunde ; Röntgenganzkörperbestrahlung ; Plasmacorticosteron
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung 1. Männliche Albinomäuse wurden gruppenweise Einzelbelastungen wie Äthernarkose, Hautwunde und Röntgenganzkörperbestrahlung von 250 R ausgesetzt. Dabei zeigte sich ein grundsätzlich gleichartiges Verhalten der Plasma-Corticosteronkonzentration mit kurzfristigem initialem Anstieg und nachfolgendem Abfall unter den entsprechenden Wert des Tagesprofils unbehandelter Kontrolltiere. 2. Das kombinierte Trauma bestand aus einer Hautwunde mit nachfolgender Röntgenganzkörperbestrahlung von 250 R. Der zeitliche Abstand zwischen beiden Belastungen betrug 24 und 96 Std. Dabei fand sich nach einem 24stündigen Intervall ein wesentlich stärkerer und länger andauernder Anstieg der Steroidkonzentration. 3. Die bei kombinierten Traumen mit 24stündigem Intervall vonFridrich (1963) undFlemming u.Flemming (1964) beobachtete Senkung der Mortalität ließe sich somit durch die verstärkte Corticoidsekretion der Nebennierenrinde erklären.
    Notes: Summary 1. Male albino mice were subjected to single traumata like aether anaesthesia, skin wound and total body X-irradiation of 250 R. In all animals the plasma corticosterone level showed a brief initial elevation with a following decrease under the corresponding value of resting animals. 2. The combined trauma consisted of a skin wound with following total body X-irradiation of 250 R. The interval between the two traumata was 24 and 96 h. The plasma corticosterone level showed a higher and longer elevation after the 24 h interval. 3. The decrease in mortality reported byFridrich (1963) andFlemming andFlemming (1964) in combined injuries with an interval of 24 h could be explained by the elevated level in plasma corticosterone.
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  • 6
    ISSN: 1432-1335
    Keywords: DNA content ; Squamous cell carcinoma ; Cell line ; Protein synthesis ; Head and neck
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Aneuploidy, as abnormal nuclear DNA content, is considered almost positive evidence of malignancy. In this study three diploid and three aneuploid squamous cell carcinoma (SCC) cell lines were examined for DNA content by flow cytometry. The DNA indices of the SCC cell lines were found to range from 1.0 to 2.1. The mitotic activity of the diploid cell lines was 1.6 times higher and the cells were smaller than aneuploid cells. To find a molecular basis for these differences, the pattern of the de-novo synthesized proteins was analyzed by means of [35S]methionine incorporation, electrophoresis, and autoradiography. In all aneuploid SCC cell lines tested in this experiment, the increase of nuclear DNA content is associated with the synthesis of a novel protein with a molecular mass of approximate 55 kDa as well as with altered synthesis rates of two preexisting proteins (50 kDa and 100 kDa). For determination of the amino acid uptake in diploid and aneuploid cells, the accumulation of [35S]methionine was measured as a function of time by liquid scintillation counting. No significant difference was found in the uptake rate between diploid and aneuploid cells with the same protein content. However, discrepancies were revealed when equal numbers of cells with different DNA index were used, suggesting, that protein turnover is different in diploid and aneuploid SCC cells.
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  • 7
    ISSN: 1432-1912
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The experiments were carried out in order to investigate the functional significance of substitution of noradrenaline by amines known to exert actions weaker than those of the natural transmitter. On the isolated rabbit heart the potency relative to noradrenaline of (±)-dihydroxyephedrine to increase the rate was 1/4 and the potency to augment the contractile amplitude was 1/6. The corresponding values for (±)-dihydroxypseudoephedrine were 1/67 and 1/140, respectively. Anesthetized rabbits were infused for 20 min with 85 μg/kg · min dihydroxyephedrine and dihydroxypseudoephedrine, respectively, and bled 15 min later. The infusions caused only minor alterations of the blood pressure. The hearts contained significant concentrations of the amines previously infused and there was a corresponding depletion of noradrenaline. After repeating the infusions once or twice at time intervals of 2 hrs both the loss of noradrenaline and the uptake of exogenous amine were enhanced. The hearts were isolated with the sympathetic nervous supply from the right stellate ganglion intact and perfused. At the end of the perfusion experiment which lasted about one hr the total amine concentrations expressed as μg/g wet weight had decreased. However, the proportion of noradrenaline to dihydroxyephedrine was unaltered. In contrast, the proportion of noradrenaline to dihydroxypseudoephedrine was increased since the latter amine was lost from the heart more rapidly than dihydroxyephedrine. Sympathetic stimulation released a mixture of noradrenaline and the previously infused amine which, therefore, behaved as a “false” transmitter substance. The ratio of the amines did not differ significantly from the ratio found in the hearts after termination of the perfusion experiment. In control hearts sympathetic nerve stimulation with pulses of 0,25–20 per second caused a gradual increase in heart rate and contractile amplitude. Pretreatment of rabbits with infusions of dihydroxyephedrine or dihydroxypseudoephedrine shifted the stimulation frequency/response curves to the right, thus indicating sympathetic transmission failure. The response to nerve stimulation was more easily blocked at the lower stimulation frequencies. There was also an increase in the threshold frequency just evoking a sympathetic response. Tyramine and dimethylphenyl-piperazine (DMPP) were infused at a constant rate into the hearts of normal and pretreated rabbits. In control hearts both drugs produced a comparable stimulation, but tyramine increased the noradrenaline output much less than DMPP. Similarly, after infusions of dihydroxyephedrine and dihydroxypseudoephedrine, tyramine released only little noradrenaline into the perfusate but caused a large increase in “false” transmitter output. This was accompanied by a stimulatory action on the heart which was less marked than that observed in controls after a comparable noradrenaline release. DMPP, especially at higher doses, increased the output both of noradrenaline and previously infused amine. It is concluded that DMPP simulates the effect of sympathetic nerve stimulation much more than tyramine does. The extent of sympathetic transmission failure is inversely related to the stimulation frequency and depends primarily on a decrease of noradrenaline release.
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  • 8
    ISSN: 1432-1912
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
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  • 9
    ISSN: 1432-1912
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
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  • 10
    ISSN: 1432-1912
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
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