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  • 1980 - 1984  (308,256)
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  • 1
    facet.materialart.
    Cold Spring Harbor, N.Y. : Cold Spring Harbor Laboratory
    Associated volumes
    Keywords: Cancer cells
    Notes: Please search for single volumes in "Reihe (alphabetisch)" or "Reihe (Stichwort)"
    ISSN: 0743-2194
    Subsequent Title: Leerer Normsatztext
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  • 2
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    Totowa, NJ : Humana Press
    Keywords: Molecular Biology / methods
    Notes: This is a series title, single volumes see link below.
    ISSN: 1940-6029
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  • 3
    ISSN: 1435-1803
    Keywords: cardiac tamponade ; pericardial effusion ; cardiac output ; myocardial blood flow
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Intravascular volume expansion has been shown to improve cardiac output in experimental cardiac tamponade. To determine the limitations of intravascular volume manipulation, acute tamponade was created in 20 anesthetized, spontaneously breathing dogs. The intrapericardial volume causing tamponade was determined for each animal, and kept constant. Hemodynamics were recorded with and without tamponade at multiple levels of intravascular volume. During cardiac tamponade, intravascular volume expansion increased cardiac output only in animals which were initially volume-depleted. Volume expansion of normovolemic or hypervolemic animals caused minimal changes in cardiac output, but increased atrial and aortic pressures. Intravascular volume depletion of the normovolemic animal caused a significant decline in cardiac output, in contrast to the trend towards an increased output following phlebotomy of the volume-expanded animals. In general, the benefit of intravascular volume expansion during cardiac tamponade could only be demonstrated when atrial pressures were below 12 mm Hg.
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  • 4
    ISSN: 1435-1803
    Keywords: lactate levels ; endocardial/epicardial blood flow ratio ; myocardial metabolism ; pericardial effusion ; radioactive microspheres
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary To determine the effects of cardiac tamponade on myocardial blood flow and its distribution, dogs were prepared with indwelling pericardial catheters. Hemodynamic, myocardial blood flow, and myocardial metabolic data were collected in 5 closed-chest, spontaneously breathing animals with normal blood volumes and hemoglobin concentrations and 6 with acute anemia. Instillation of an average of 89.0±14.9 ml of modified Normosol® into the pericardial space in dogs with normal hemoglobin levels produced mild tamponade with a modest decline in aortic pressure (119.5±14.3 to 96.8±12.1 mm Hg) and significant rises in left and right atrial and pericardial pressures to 7–8 mm Hg. Increasing the pericardial volume to 124.0±13.6 ml produced hypotension (mean aortic pressure 86.2±10.5 mm Hg) and rises in the left and right ventricular filling pressures and pericardial pressure to 10–11 mm Hg. Total myocardial blood flow fell from 1.19±0.18 to 0.73±0.17 ml/min/g (p<0.02) during mild tamponade, and fell further to 0.56±0.17 ml/min/g (p<0.05) with more severe tamponade. Despite these declines, the left ventricular wall inner/outer flow ratio and left ventricular flow as a proportion of total cardiac output were unchanged. In dogs with anemia more severe tamponade was created, with consequently more marked hemodynamic abnormalities. However, the relative changes in myocardial blood flow and inner/outer flow ratio were similar. Myocardial metabolic parameters could be evaluated only in the dogs with less severe tamponade. The coronary arteriovenous oxygen difference changed little during induced tamponade, and, therefore, quantitated myocardial oxygen consumption declined in proportion to the fall in myocardial flow. Furthermore, myocardial lactate extraction and the lactate/pyruvate ratio were not affected by cardiac tamponade. Thus, these experiments cannot support the hypothesis that myocardial ischemia is a pathophysiologic factor in the production of abnormal hemodynamics in cardiac tamponade.
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  • 5
    ISSN: 1435-1803
    Keywords: carnitine ; perfused rat heart ; long-chain acyl coenzyme A
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The metabolic and physiologic differences between low-flow and zero-flow ischemia of varying duration were compared in the isolated perfused rat heart. Hearts subjected to 60 and 90 minutes of zero-flow ischemia recovered less cardiac work than hearts subjected to low-flow ischemia. Low-flow ischemia caused a build-up of both myocardial long-chain acyl coenzyme A and acyl carnitine esters, while zero-flow ischemia produced no change in long-chain acyl carnitine and only a transient increase in long-chain acyl coenzyme A. High energy phosphate depletion was greater in zero-flow ischemia. Perfusion with excess free fatty acids decreased the recovery of cardiac work after low-flow ischemia but had no effect after repeated episodes of zero-flow ischemia. L-Acetylcarnitine improved the recovery of cardiac work after low-flow ischemia in hearts perfused with 0.4 and 1.2 mM palmitate. With zero-flow ischemia, L-acetylcarnitine had no effect on the recovery of cardiac work in hearts perfused with 0.4 mM palmitate and a slight but statistically significant effect with 1.2 mM palmitate. Possible protective mechanisms of L-acetylcarnitine against ischemic damage are discussed.
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  • 6
    ISSN: 1435-1803
    Keywords: tonicity ; osmolality ; global and regional ischemia ; reperfusion ; “no-reflow”
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary We studied the effect of tonicity of the perfusate during reperfusion after global ischemia, in both the rat and the porcine heart. After 50 min, tissue osmolality increased by about 40 mOsm/kg. Normotonic as well as hypertonic reperfusion resulted in limited areas of “no-reflow”. Metabolic restoration after reperfusion was not dependent on the tonicity of the perfusate, nor was recovery of contractility. Hypertonic reperfusion induced a higher coronary flow rate. In porcine hearts, scatter of metabolic data indicated inhomogencity of reperfused tissue. The results differ substantially from data obtained after reperfusion of regionally ischemic hearts. Reasons for these differences are discussed.
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  • 7
    ISSN: 1435-1803
    Keywords: hemorrhage ; volume regulation ; transvascular fluid shift ; arterial pressure ; alert rat ; cardiovascular receptors ; blood conductivity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Blood (3.4–13.5% of blood volume) was pumped in and out of the circulation of rats at different rates and period lengths during continuous measurements of blood conductivity (reciprocally related to hematocrit) and arterial pressure. Hct followed the same zig-zag course as the induced changes of blood volume in every case, indicating that fluid shifts (δv) between interstitium and intravascular space closely follow blood volume changes. As the het increase during reinfusion was not as great as the preceding decrease, hct dropped continuously during the 20–90 minutes of experimentation, so that a final volume increase (δv) by about 4% was calculated, which was confirmed by a corresponding decrease of plasma protein concentration. Both final δv and δv during periodic volume change (δ% B.V.) were greater when arterial pressure dropped. δv was directly related to δ% B.V. but not to its rate of change. Heart rate dropped slightly at the end of the reinfusion periods, whereas it rose to control at the end of the withdrawal periods. The results were regarded as evidence of blood volume regulation proportional to the absolute volume of blood lost in non-hypotensive hemorrhage.
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  • 8
    ISSN: 1435-1803
    Keywords: prazosin ; urapidil ; acute administration ; chronic administration ; renin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The effects of prazosin (0.1, 0.5 and 2.5 mg/kg, orally) on blood pressure, heart rate and PRA were investigated after acute and chronic administration in conscious, normotensive dogs. The acute administration of prazosin caused a reduction in both systolic and diastolic blood pressure and an increase in heart rate and PRA. After chronic administration, twice daily for four days, tolerance developed, which was not due to persistent counterregulation. On comparison with urapidil, another α-adrenoceptor antagonist, the hypotensive and counterregulatory response to acute administration were similar with both substances; the development of tolerance to prazosin after chronic administration contrasted with the results with urapidil.
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  • 9
    ISSN: 1435-1803
    Keywords: propyldazine ; dihydralazine ; counterregulation ; renin angiotensin aldosterone system
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The magnitude and the persistence of blood pressure reduction by propyldazine (PDZ) was investigated following treatment over a period of 4 days. The experiments were performed on 6 normotensive dogs trained to submit to puncture of the femoral artery and to stand quietly in a special frame over the experimental period of 7 to 8 hours. The first dose effect of orally administered PDZ (0.06, 0.29 and 1.42 mg/kg) on heart rate, arterial blood pressure and plasma renin activity (PRA) was compared with the fffect of the substance after treatment at the same respective dosage twice daily over 4 days. The compound caused a dosedependent decrease in blood pressure accompained by dose-dependent increases in heart rate and PRA. With 0.06 mg/kg and 0.29 mg/kg PDZ a sustained effect on arterial blood pressure was observed, whereas with 1.42 mg/kg PDZ tolerance occurred after treatment over the 4-day period. A comparison with the effects observed previously with 1.42 and 7.1 mg/kg dihydralazine (DHZ) under identical conditions showed similar results with respect to dose-dependence of blood pressure and counterregulation (1). It is considered that with a low-doseregimen there would be no decrease in activity of PDZ, the long-term hypotensive efficacy of the drug thereby being guaranteed.
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  • 10
    ISSN: 1435-1803
    Keywords: cardiac cells ; active Na transport ; electrogenic Na pump ; Na−Ca exchange ; action potential ; pacemaker activity ; arrhythmias
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary An ATP-driven Na pump maintains the unsymmetrical Na and K distribution across the cell membrane of cardiac cells. An increase of the intracellular Na or extracellular K concentration enhances this active Na transport. About 35 per cent of the actively transported Na is ejected from the cells as a hyperpolarizing outward current. The Na pump influences the cardiac Ca metabolism via the Na−Ca exchange. Inhibition of the pump affects the generation and conduction of the cardiac action potential by various mechanisms. It seems to be involved in the genesis of cardiac arrhythmias.
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  • 11
    ISSN: 1435-1803
    Keywords: heart sarcolemma ; Ca2+-stimulated ATPase ; ATP-dependent Ca2+ binding ; β-adrenergic antagonists
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The effects of some β-adrenergic antagonists such as acebutolol, propranolol, pindolol and oxprenolol (1–1000 μM) were studied on the rat heart sarcolemmal Ca2+ transport activities. Pindolol enhanced sarcolemmal ATP-dependent Ca2+ binding and Ca2+-stimulated ATPase whereas acebutolol had no effect. Both propranolol and oxprenolol had biphasic actions on the sarcolemmal Ca2+ pump activities; the lower concentrations (1 and 10 μM) were stimulatory, but the higher concentrations (100 and 1000 μM) were inhibitory. None of the drugs used in this study had any effect on Mg2+ ATPase and non-specific Ca2+ binding activities of heart sarcolemma except that 1000 μM propranolol decreased Mg2+ ATPase activity significantly. Mitochondrial and microsomal ATP-dependent Ca2+ binding activities were unaffected by these drugs (1–1000 μM), except that 1000 μM propranolol was inhibitory. These results suggest differences among various β-adrenergic blocking drugs with respect to their actions on sarcolemmal Ca2+ pump in the myocardium.
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  • 12
    ISSN: 1435-1803
    Keywords: His bundle electrocardiography ; atrioventricular conduction ; heart ; atria ; pacing ; atrioventricular conduction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The conventional catheter method for measuring specialized A-V nodal and His-ventricular conduction times in the intact dog heart precludes an unanesthetized control. This control is necessary for meaningful studies of the effect of drugs or drug-drug interactions on A-V conduction times. At right thoracotomy (halothane anesthesia), mongrel dogs had bipolar electrodes sutured to the epicardial surface of both atrial appendages, juctions of the sulcus terminalis with both vena cavae, and right ventricle. A unipolar needle electrode, referenced to a unipolar electrode on the ascending aorta, was inserted into the interatrial septum from the aortic root for recording the His bundle electrogram. After one to three weeks for stabilization, weekly measurements were made of A-V nodal conduction time (AVN) and His-ventricular conduction time (H-V) for up to 52 weeks (4 to 52 weeks). Mean values (13 dogs) for spontaneous cycle length, AVN and H-V conduction times were 477±25, 82±3, and 30±1 msec, respectively. Simultaneous recordings from catheter and implanted His bundle electrodes were made during changes in atrial paced rate (five dogs, pentobarbital anesthesia). Values for AVN and H-V conduction times from catheter or implanted electrodes were the same. AVN conduction time increased, H-V conduction time remained constant during increases in atrial rate. Atropine shortened and propranolol prolonged AVN conduction time in six unanesthetized, unsedated dogs; neither affected H-V conduction time. Histologic examination of electrode sites in two dogs at 43 and 52 weeks showed no evidence of damage to underlying myocardial recording sites. This preparation provides reproducible awake values for AVN and H-V conduction times, and hence a more meaningful control for pharmacologic investigations.
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  • 13
    ISSN: 1435-1803
    Keywords: sinoatrial conduction time ; method of Strauß ; modified method of Narula ; reproducibility ; parasympathicolysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Using intracardiac recordings of electrical activity and programmed electrical right atrial stimulation of the human heart, the sinoatrial conduction time (SACT) in the method of Strauß et al. 1973 (SACTc) was calculated in 80 patients with and without disturbances of rhythm and compared to the modified measurement of the SACT in the method reported by Narula et al. in 1978 (SACTN). The number of continuously stimuli varied from 4, 8 and 16 stimuli with a frequency of 10% just above the averaged spontaneous frequency. The best correlation was found between the SACTc and the SACTN16 (r=0.74; p<0.001) with a regression line of: SACTN16=1.04 SACTc+28.6. Under these conditions, as opposed to SACTN4 or SACTN8, the most favourable reproducibility and relative coefficient of variation (rVk) could be observed: SACTN16; rVk=9.5%; r=0.91; SACTN8. rVk=12.3%; r=0.89; SACTN4: rVk=24.3%; r=0.53. Higher individual values for SACTN16 were found by continuous atrial stimulation as compared to other methods of determination indicating mainly a higher depression of sinus node automaticity due to overdrive suppression. Under parasympathicolysis (1 mg atropine)_the lowest values of SACT were found for SACTN4 (45.9±20.7 ms) coming closest the “true” SACT, since under these conditions neither an increase of the refractory period nor an overdrive suppression exert an influence.
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  • 14
    ISSN: 1435-1803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary There is experimental evidence that the bimodally distributed ventricular arrhythmias (phases Ia and Ib) during the first 30 min after coronary occlusion (CO) in dogs are not due to the same mechanism. In 39 dogs we related the incidence of phases Ia and Ib to the time courses of excitation thresholds (ET), refractoriness (REFR), conduction times (CT) and effective refractory periods (ERP) at 6–12 epicardial electrode sites within the ischemic zone. The regional collateral myocardial blood flow (RMBF-tracer microsphere technique) was determined in 14 out of the dogs. This measurement only served for rough grouping into dogs with low and higher RMBF at the electrode sites during ischemia. REFR was determined as temporal recovery of excitability at a constant current strength of 4–6 times preocclusion ET. ERP was intermittently measured at 2.0–8.0 mA. At low RMBF ET, REFR and CT increased very
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  • 15
    ISSN: 1435-1803
    Keywords: Ca2+ overload ; ionophore A23187 ; ouabain ; dexamethasone ; indomethacin ; phospholipase A2 ; triggered arrhythmias
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The mechanism of spontaneous diastolic depolarizations induced by different Ca2+ overloading conditions (ouabain toxicity, calcium ionophore A23187, O-K, high Ca2+ solution) in mammalian working myocardium fibres was studied with conventional microelectrode technique and pharmacological approach. Antagonistic properties of antiphospholipase-A2 (PL A2)-active compounds (dexamethasone and indomethacin) were tested. Membrane oscillation in Ca2+ overload conditions were shown to be eliminated or largely protected by both anti-inflammatory agents. There was no influence of the compounds on electrical parameters and ion currents in intact mammalian and amphibian myocardium. The data obtained suggested that modulation of Ca2+-dependent PL A2 activity may contribute significantly to membrane destabilization due to Ca2+ overload of cardiac cells. An analogous membrane destabilizing action of exogenous PL A2 observed in Langendorff-perfused guinea pig heart is in favour of the hypothesis introduced.
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  • 16
    ISSN: 1435-1803
    Keywords: acetylstrophanthidin ; beta-sympathomimetics ; arrhythmias ; impaired coronary blood supply ; conscious dogs
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The enhanced arrhythmogenic risk of combined treatment with cardiac glycosides and beta-sympathomimetics is referred in some textbooks, but only a few detailed studies on in vivo models are available. We therefore investigated this problem in conscious dogs in an intraindividual study. We determined the dose of acetylstrophanthidin (intravenous infusion of 5 mcg/kg per min), which provoked ventricular premature beats with and without concomitant treatment with the partial betaagonistic compounds doxaminol (3 mg/kg p.o.), prenalterol (0.4 or 1.0 mg/kg p.o) or isoprenaline (0.31±0.100 mcg/kg per min). In some dogs a coronary artery was narrowed in order to reduce the coronary blood supply. The arrhythmogenic dose of acetylstrophanthidin was nearly the same in all the groups investigated (range from 52.1±5.66 to 59.9±3.23 mcg/kg). Whereas the arrhythmogenic dose of acetylstrophanthidin was unchanged by beta-sympathomimetics, the combination of the glycoside and each of the beta-agonistic drugs increased the contractile force more than did either single compound. We therefore conclude that the arrhythmogenic risk of the combination of glycosides and betasympathomimetics may be — at least in experimental models — less than has been suggested in the past.
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  • 17
    ISSN: 1435-1803
    Keywords: ventricular fibrillation ; acetylcholine ; methacholine ; self-defibrillation ; induction of fibrillation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The influence of cardiac cholinergic activation was studied in rats and cats on the induction and maintenance of ventricular fibrillation (VF). Acetylcholine (ACH 2–25 μg/kg), in doses which did not cause bradycardia or hypotension, induced appearance of spontaneous VF (duration 2–60 sec.) in 9/20 rats which have a high sympathetic autoregulation and in 3/6 cats only, 20–40 secs after the latter had been given adrenaline. ACh (10–45 μg/kg) and methacholine (10–40μg/kg) also significantly prolonged the fibrillatory period induced electrically in cats and rats with and without atrial or ventricular pacing. The induction or prolongation of VF did not occur when higher doses of ACh (50–100 μg/kg) were given to rats. The influence of moderate amounts of cholinergic agents on the heart may be due to localised effects resulting in asynchronous activity. Alternatively, they may produce a discharge of multiple ectopic pacemakers or a disturbance in impulse conduction. Higher doses of ACh depress the S-A and ventricular ectopic activity node thereby decreasing the probability of inducing VF. It is concluded that under conditions of raised cardiac adrenergic activity, a moderate increase in cholinergic influence can both induce and prolong VF. The relevance of these findings to the “sudden infant death” syndrome is discussed.
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  • 18
    Electronic Resource
    Springer
    Basic research in cardiology 79 (1984), S. 698-698 
    ISSN: 1435-1803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
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  • 19
    ISSN: 1435-1803
    Keywords: streptokinase ; coronary thrombosis ; acute myocardial infarction ; electrical coronary stimulation ; canine experiments
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The thrombolytic and hemodynamic properties of intracoronary streptokinase (SK) application were studied in anin-vivo canine model with left circumflex coronary artery thrombosis, initiated by electrical stimulation (150 μA, DC for 6 h) of the artery's intima via an implanted silver wire. In pentobarbitalanesthetized, open-chest dogs acute myocardial ischemia was determined by a dehydrogenase-dependent staining of the coronary artery perfusion area. Thrombus weight was determinedpost-mortem. Saline-treated control animals developed coronary thrombosis after 3.1±0.4 h of stimulation. Thrombus weight was 64±3.1 mg. Acute infarct volume was 32±3.1% of total left ventricle, and 53±6.2% of the coronary artery risk region for infarction. At occlusive thrombosis, blood pressure, ventricular pressure and the LV dP/dtmax fell significantly, whereas heart rate and the end-diastolic filling pressure increased. Severe ST-segment elevation and loss of R wave voltage indicated myocardial ischemia. At 20 min into thrombotic vessel occlusion, 2,000 IU/min SK were infused by way of a Sonescatheter advanced to the thrombus. Coronary thrombosis consistently lysed after 12±0.7 min of SK infusion, and coronary blood flow as well as hemodynamics were restored. Only minor acute infarction was found indicating viability of ischemic jcopardized myocardium. In another group, the continuous SK-infusion (20 IU/kg/min) concomitant with electrical vessel stimulation prevented coronary thrombosis and acute ischemia, and no significant hemodynamic alterations were noted. These results indicate that intracoronary SK-infusion can lyse acute thrombosis as sequel of electrical stimulation. This prevents development of acute myocardial infarction. Continuous SK-infusion can completely prevent coronary thrombosis in response to intimal injury.
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  • 20
    ISSN: 1435-1803
    Keywords: blood pressure variability ; blood pressure reactivity ; hypertension ; stress ; age ; sex
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Blood pressure variability under basal conditions and blood pressure reactivity to emotional stress were studied in 38 hypertensives and 13 normotensives. Systolic basal blood pressure variability correlated with systolic blood pressure reactivity. Variability increased with higher basal blood pressure. Thus in the hypertension group the blood pressure variability was greater than in the normotension group. Besides, the hypertension group showed a greater reactivity of systolic blood pressure to emotional stress, too. An influence of age on basal blood pressure, blood pressure variability, and reactivity could be evaluated; but no influence of sex on these parameters was detected. The results indicate that variability and reactivity of blood pressure can be referred to a common central nervous blood-pressure-regulating mechanism. As both parameters are increased in hypertension, a greater lability of blood pressure must be assumed. This greater lability may be attributed to a stronger neurogenic influence or to structural changes of peripheral blood vessels.
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  • 21
    ISSN: 1435-1803
    Keywords: ischemic stress ; oxygen debt ; release of substrates and electrolytes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary As criterion for the degree of ischemic stress on myocardium during repeated cronary artery occlusion, the reproducibility of the release of potassium, lactate and inorganic phosphate in the early reperfusion period was examined. On 20 anaesthetized open-chest mongrel-dogs, local ischemia was induced by intermittent occlusion of the LAD artery. In each experiment the artery was occluded for 3 min 4 to 6 times with intervals of 45 min. Just before beginning, at the end of occlusion and after 5 min of reperfusion, arterial and coronary venous blood was collected simultaneously. Additionally, 3 ml of blood were withdrawn by syringe-pumps during the first minute of reperfusion. Intraindividually, the following standard-deviations were found in a representative experiment with 5 occlusions: potassium ±7% (22.62±1.6 μmol/min); inorganic phosphate ±9% (19.82±2.06 μmol/min); lactate ±11% (55.38±5.93 μmol/min). Interindividually, the correlation between the release of these markers and the perfusion bed of the ligated artery led to coefficients of about r∼0.88. On an average, per gram ischemic tissue/wet weight 0.74 μmol potassium, 0.6 μmol inorganic phosphate and 1.98 μmol lactate were released. The ratios between the releases remained constant independent of the size of ischemic area. An even closer correlation with coefficients of about r∼0.97 was found between the releases and the O2-debt in the occlusion period. Based on a synoptic assessment of metabolic and energetic parameters, this experimental model may render more detailed information on pharmacological interventions during ischemic stress.
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  • 22
    ISSN: 1435-1803
    Keywords: hemodynamics ; pulsatile flow ; particle paths ; aneurysm ; finite elements
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The velocity field and the wall shear stress have been calculated numerically by the finite element method to the time-dependent Navier-Stokes equations for pulsatile flow in a model of an aneurysm. The results show a complex flow field with two eddies growing and disappearing during the cardiac cycle. Downstream at the outlet vessel high wall shear stress occurs, which may lead to a downstream-growing of the aneurysm. With the knowledge of a sufficiently accurate flow field, the calculation of several particle paths has been carried out. Starting points and starting time are varied. The paths demonstrate the time-dependent development, shift and disappearance of vortices during the pulsatile cycle and provide hints on zones of stasis. These are significant factors in thrombogenesis.
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  • 23
    ISSN: 1435-1803
    Keywords: coronary artery occlusion ; border zone of myocardial infarction ; tissue pH ; glycogen depletion ; tissue perfusion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In open-chest dogs, the left anterior descending coronary artery was ligated for 150 min. The heart was semiserially cut on a cryomicrotome and areas of ischemic damage were visualized by means of glycogen depletion (PAS reaction) and tissue acidosis (a “sandwich” technique with pH indicator dispersed in a layer of gel). The extent of myocardial damage was determined morphometrically. The mass of the glycogen-depleted heart muscle was greater than the mass of the ischemic tissue detected by means of decreased pH (p<0.01). The border zone was characterized by glycogen depletion without acidosis. Circulation studies using intravital fluorescein staining have shown that perfusion is partially retained in the border zone; it is assumed that the hypoperfusion triggers glycogenolysis. Nevertheless, the level of perfusion suffices to wash out the acidic end products. Comparison of contrapulsation-treated dogs and untreated dogs shows that the amount of damaged tissue comprising the border zone can be reduced by this therapeutic intervention (p<0.02)—in contrast to the acidotic tissue, the amount of which is not significantly influenced. Therefore the border zone contains damaged but still viable muscle cells.
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  • 24
    ISSN: 1435-1803
    Keywords: experimental chronic pulmonary hypertension ; simultaneous multiple treatment ; Verapamil ; Captopril ; Aspirin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In Wistar rats, rendered pulmonary hypertensive by chronic confinement in normobaric “hypoxic cages”, impairment of transmembrane transport of calcium by Verapamil and blockade of the action of Angiotensin I converting enzyme by Captopril when applied simultaneously did not show an additive effect in reducing the rise of pulmonary artery pressure and decreasing the augmentation of right ventricular mass. Similarly, the action of Verapamil together with decrease of prostaglandin synthetase activity by Aspirin showed no additive effect. Although in this way the results of the present study failed to give substantial support to the idea of the existence of several mediators of hypoxic pulmonary vasoconstriction, they by no means deny this possibility.
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  • 25
    ISSN: 1435-1803
    Keywords: perfusion pressure ; contracture ; no-reflow ; anoxia ; rat heart ; lactate accumulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The relationships among coronary perfusion pressure (0–150 cm H2O), ventricular contracture, vascular resistance, and loss of perfusion of subendocardial myocardium were studied in anoxic isolated rat hearts. Coronary flow and myocardial pH and lactate concentrations were measured during 60 minutes, and the perfusable proportion of the ventricular wall determined after 15 and 60 minutes of global, substrate-free anoxic perfusion. Myocardial contracture in similarly treated hearts was indicated by the pressure exerted on left intraventricular balloons. Decreased perfusion pressure proportionately decreased both coronary flow and the extent of perfusion, and delayed the onset of contracture. The slower development of contracture was associated with a measured increase in lactate content and fall in pH within the ventricular wall. During anoxia the subendocardial myocardium progressively lost its capacity to be perfused, commencing at the onset of ventricular contracture, and continuing to extend even after maximum contracture pressures had been developed. Increased coronary perfusion pressures accelerated the rate of development of contracture but significantly reduced the extent of the perfusion defect, probably by opposing vascular compression.
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  • 26
    ISSN: 1435-1803
    Keywords: oxygen consumption ; internal work ; external work ; source resistance ; afterload impedance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The relationship between myocardial oxygen consumption ( $$M\dot VO_2 $$ ) and left ventricular work was examined experimentally, assuming that the left ventricle is equivalent to an electrical current source generator consisting of parallel source resistance (Ri) and constant generator current (I0). The internal and external work can be calculated as (Ri×I1 2) and (Rp×I2 2) in this model, where I1 is current of source resistance, Rp is peripheral resistance and I2 is cardiac output. The experiments were performed with a blood-perfused isolated ejecting canine heart preparation in which the hydraulic model, simulated to an aortic input impedance, was attached to the aortic root. The peripheral resistance was changed in a stepwise fashion and left ventricular pressure, cardiac output and $$M\dot VO_2 $$ were measured. The calculated total work showed a close linear correlation with the $$M\dot VO_2 $$ which suggested that the left ventricle can be regarded as a current source generator and the total work as a main mechanical factor in determining the $$M\dot VO_2 $$ .
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  • 27
    ISSN: 1435-1803
    Keywords: volume overload ; ventricular hypertrophy ; myocardial blood flow ; myocardial ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In this study we investigated myocardial structural alterations and regional myocardial blood flow in chronic volume-overload induced left ventricular hypertrophy in the dog. Moderate hypertrophy (28%) was produced by inserting a shunt between the left subclavian artery and the left atrial appendage in 7 dogs (LVH), while a sham operation was performed on 5 control dogs (C). At a paced heart rate of 100 beats/min there were no differences in blood-flow distribution to the subendocardium (ENDO) mid-myocardium (MYO) or subepicardium (EPI) or in ENDO/EPI ratios between the two groups of dogs. Following adenosine-induced coronary vasodilatation (1 mg/kg/min), there was a relative shift in blood flow away from the ENDO in the LVH dogs so that the ENDO/EPI ratio was reduced. Analysis of the microvascular bed and myocyte cross-sectional area in the same three regions of interest revealed a significant reduction in capillary density in the ENDO region of the hypertrophied hearts when compared to controls (LVH=2463±10, C=2773±75 caps/mm2) and a corresponding increase in myocardial cell cross-sectional area (LVH=262±10, C=233±36 μm2). The reduction in capillary density in LVH may be explained on the basis of increased muscle growth without appropriate capillary proliferation indicating an inadequate neovascular response to this form of overload. The results also indicate that blood-flow distribution abnormalities may not be detected at resting flow with moderate LVH produced by volume overload.
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  • 28
    ISSN: 1435-1803
    Keywords: cardiac hypertrophy ; diffusion distance ; cardiac aging ; spontaneous hypertension ; terminal vascular bed
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Cardiac mass, cell size and capillary supply were studied in the hearts of spontaneously hypertensive rats (SHR) and compared to genetically similar non-hypertensive Wistar-Kyoto (WKY) of three adult ages: 5, 15 and 23 months. The left ventricular weight of SHR was not significantly greater than that of WKY at 5 months, but was 15 months and became even more so by 23 months. This increase could be attributed to hypertrophy of the individual cardiac muscle cells and therefore, the estimated total number of myocytes per left ventricle was essentially the same in all experimental groups. Various indices of the myocardial capillary supply were also investigated. Cardiac hypertrophy in older hypertensive rats was characterized by greater and more variable intercapillary spacing, which may have importance in myocardial oxygen supply.
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  • 29
    ISSN: 1435-1803
    Keywords: cardiac hypertrophy ; ouabain ; digitalis receptors ; Na+ ; K+-ATPase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Left ventricular hypertrophy was established in young pigs (35–40 kg) after 4 weeks of supravalvular aortic stenosis. Isolated sarcolemmal membrane fraction was characterized for specific3H-ouabain binding. Analysis revealed a single class of receptor sites of 5.7 p moles/mg protein and a dissociation constant (Kd) of the order of 6.25×10−8 M. Measurement of specific3H-ouabain binding with sarcolemmal fraction isolated from hypertrophied heart revealed a 26% reduction of digitalis receptor after 4 weeks of aortic stenosis, without any significant change in the affinity of receptor sites. This change in the number of digitalis receptors was maintained between 4 and 8 weeks of aortic stenosis and may be an important adaptive mechanism.
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  • 30
    ISSN: 1435-1803
    Keywords: left ventricular power ; preload ; afterload ; extracorporeal circulation ; quantitative left ventricular cineangiography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary To investigate whether left ventricular performance can be described independent of loading conditions, twelve patients underwent intraoperatively two cineangiographies of the left ventricle with simultaneous pressure recordings. The first ventriculography was performed with ejecting left ventricle without assistance by the extracorporeal circulation. The second one was performed with ejecting left ventricle partially unloaded by the extracorporeal circulation. Myocardial perfusion pressure (mean aortic pressure) was held constant. Due to this procedure marked decreases in preload (end-diastolic wall stress: −54%) and modest changes in afterload (mean systolic wall stress: −23%) were achieved. End-diastolic volume index was reduced from 84 ml/m2 to 57 ml/m2, whereas end-systolic volume index decreased slightly from 33 ml/m2 to 29 ml/m2. Left ventricular end-diastolic pressure decreased from 12 mm Hg to 7 mm Hg, while peak pressure remained nearly unchanged. Usual parameters of ejection phase (EF, Vmw) as well as power per wall volume (PW) were markedly affected by unloading. In contrast to these parameters, the power index (PI), i.e., the ratio of power per wall volume and enddiastolic wall stress, remained unchanged when left ventricular preload was reduced: PI under control: 5.2±1.8 sec−1; PI under unloading: 5.2±1.5 sec−1. This power index can easily be determined from routine angiographies. It may provide a new approach to the assessment of left ventricular function in man.
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  • 31
    ISSN: 1435-1803
    Keywords: pressure-diameter ratio ; late systolic stress-diameter relationship ; aortic valve disease ; aortic valve replacement ; myocardial function
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The end-systolic pressure-diameter ratio (Ees) and the maximal pressure-diameter ratio (Emax) during systolic ejection were determined in 10 control patients and 25 patients with aortic valve disease before and 18 months after successful valve replacement. The pressure-diameter ratio was determined from simultaneous M-mode echocardiograms and high-fidelity pressure measurements. A new index of myocardial contractility, as proposed by Pouleur and co-workers, was assessed from the late systolic stress-diameter relationship during one single heart cycle. The slope of this stress-diameter relationship was used for determination of myocardial contractility. Meridional wall stress was calculated from echopressure measurements at time intervals of 5 to 10 msec. The aortic valve patients were divided into two groups according to the preoperative angiographic ejection fraction: group 1 (ejection fraction ≧57%) consisted of 16 patients and group 2 (ejection fraction <57%) of 9 patients. Standard hemodynamics showed a significant decrease in left ventricular end-diastolic pressure from 18 to 11 mm Hg in group 1 (P<0.01) and from 16 to 12 mm Hg (NS) in group 2. Peak systolic pressure decreased from 186 to 135 mm Hg (P<0.01) in group 1 and from 155 to 140 mm Hg (NS) in group 2. Left ventricular end-diastolic volume decreased from 137 to 105 ml/m2 in group 1 and from 225 to 150 ml/m2 in group 2 (P<0.05) whereas left ventricular ejection fraction remained unchanged in group 1 (67 versus 65%) and increased slightly in group 2 (45 versus 51%) following surgery. Emax and Ees were preoperatively significantly decreased in group 2 when compared to group 1. Postoperatively, Emax and Ees were no longer significantly different between the two groups although left ventricular ejection fraction remained significantly depressed in group 2 after surgery when compared to group 1. The slope of the late systolic stress-diameter relationship (β) and the diameter at zero stress (D0) did not show any difference between the two groups pre- as well as postoperatively. Thus it is concluded that Ees and Emax might help to identify myocardial dysfunction in preoperative patients with aortic valve disease. However, in the presence of persistent myocardial dysfunction, as evaluated from systolic ejection fraction, following successful valve replacement, both Ees and Emax do not allow to identify patients with postoperative depressed myocardial function. The failure of the slope of the late systolic stress-diameter relationship to distinguish between patients with normal and decreased ejection performance is due to an intrinsic relation between stress and diameter. Hence this index cannot be recommended for the assessment of contractility in patients with aortic valve disease.
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  • 32
    ISSN: 1435-1803
    Keywords: sex differences ; cardiac function ; rat heart ; isolated working heart apparatus ; heart mass
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The objective of this investigation was to compare intrinsic cardiac function in male and female rats. The first series of experiments (Series I) compared hearts from age-matched males and females at 18 weeks of age. Since body and heart weight were 65 and 51 per cent greater respectively in male rats in this study, a second series of experiments was performed (Series II) where heart mass was matched in males and females by studying males at 10 weeks of age and females at 18 weeks of age. Cardiac function was studied in an isolated working heart apparatus at similar heart rates and at controlled levels of end-diastolic pressure and aortic diastolic pressure (ADP). In Series I coronary flow and enddiastolic volume (both per g LV) were the same in male and female hearts, while stroke work (per g LV), ejection fraction and fractional shortening were significantly greater in male hearts but only as the ADP was increased. In Series II all of these measurements were significantly greater in male hearts at all loading conditions. The magnitude of the differences between male and female hearts was greater in Series II than in Series I which may have been due to a Frank-Starling effect in male hearts from Series II. The results indicate that intrinsic cardiac function is moderately greater in male rats compared to female rats. Studies employing similar size male and female hearts suggest that differences in heart mass may have accounted for the differential response to ADP in Series I.
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  • 33
    ISSN: 1435-1803
    Keywords: streptozotocin ; diabetic rats ; exercise-training ; beta-adrenergic receptors ; plasma catecholamines
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The effects of physical training on beta-adrenergic receptors were evaluated in heart ventricular tissue of diabetic rats. Mild diabetes mellitus was induced in rats with streptozotocin (45 mg/kg, iv). They were then submitted to a progressive 10-week running programme on a treadmill. Binding studies were done at six different concentrations of (−) [3H] dihydroalprenolol (0.5 to 14.4 nM) with ventricular membrane preparations from control (n=13), sedentary diabetic (n=9) and trained diabetic rats (n=10). Direct linear plot analysis of the data revealed that the total number of beta-adrenoceptors was reduced in sedentary diabetic rats as compared to control (2231±207 vs 2922±211 fmol/ventricules; P<0.05); however, there was no significant change in the receptor density expressed as fmol/mg of membrane protein (40±3 vs 43±3; P>0.05). On the other hand, the beta-adrenergic binding sites were decreased in trained diabetic rats, either expressed as the total number of receptors (1920±179 vs 2922±211; P<0.01), or as fmol/mg of membrane protein (30±3 vs 43±3; P<0.01). There was no significant change in the dissociation constant (KD) of these receptors between groups (KD=4.08±0.51, 4.69±0.93 and 2.88±0.39 nM respectively for control, sedentary diabetic and diabetic trained animals). The basal epinephrine concentration was significantly increased in trained diabetic rats (102±21 pg/ml vs 47±7 for control (P<0.05) and vs 49±9 for sedentary diabetic (P<0.05). These data indicate that a programme of physical training in diabetic rats can reduce both the total number and the density of beta-adrenoceptors in heart ventricular tissue, possibly by increasing the basal epinephrine secretion.
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  • 34
    ISSN: 1435-1803
    Keywords: myocardium ; ischemia ; infarction ; reperfusion ; pig
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary We investigated the temporal and spatial development of infarcts in porcine hearts to evaluate the time-dependent beneficial effect of reperfusion on infarct size. The left anterior descending coronary artery (LAD) was occluded in 17 pigs for different periods of time followed by 4 hours of reperfusion. Transmural needle biopsies subdivided into subendocardial and subepicardial halves were taken from the ischemic apex after 60 min of ischemia to determine the tissue concentrations of ATP and NAD. The myocardium-at-risk was assessed with a fluorescent dye injected into the right atrium at the end of the experiments, just after the LAD had been reoccluded. The excised hearts were cut into slices parallel to the heart basis. The ischemic myocardium was measured by planimetry of the nonfluorescent areas whereas the infarcted tissue was determined with the NBT stain and related to the area-at-risk. Ischemic cell death started in the jeopardized left ventricular subendocardial septum after about 30 min of ischemia. The further progress involved the right subendocardial septum and the subendocardium of the left anterior free wall. Already after 75 min of ischemia most of the myocytes-at-risk were irreversibly injured. Infarctions reached their final extent after 90–120 min of ischemia. These results indicate that in hearts without a significant collateral blood flow reperfusion can only reduce infarct size if its initiated within 60–75 min of ischemia. Like in canine hearts infarctions progress from the ischemic subendocardium towards the outer layers.
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  • 35
    ISSN: 1435-1803
    Keywords: coronary collateral vessels ; myocardial blood flow ; coronary occlusion ; ischemia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The purpose of this study was to determine whether coronary collateral blood flow changes in response to repeated brief periods of ischemia in dogs in which no attempt has been made to stimulate collateral vessel development. The dogs were instrumented with aortic and left atrial catheters and a balloon occluder on the left circumflex coronary artery and were studied in the awake state the following day. Blood flow to the collateral dependent myocardium was measured using 9 μ radioactive microspheres during four coronary occlusions of two minutes duration, each separated by one hour of reperfusion. A small but statistically significant increase in mean collateral blood flow was noted between the first and fourth occlusions; .03 to .05 ml/min/g. These data suggest that transient periods of brief ischemia may result in increases in collateral blood flow.
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  • 36
    ISSN: 1435-1803
    Keywords: myocardial mitochondria ; palmitic acid oxidation rate ; pyruvic acid oxidation rate ; Krebs cycle enzymes ; beta-oxidation enzymes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Mitochondria were prepared from the subendocardial and subepicardial layers of the canine left ventricle. The oxidation rates of palmitate, palmitoyl carnitine and pyruvate of the mitochondria obtained from the two cardiac layers were measured. The cytochrome content and the specific activities of different beta oxidation and Krebs cycle enzymes were also measured in the two mitochondrial populations. Mitochondria isolated from the ENDO layer showed significantly higher oxidation rates than mitochondria from the EPI layer for all the three substrates. No statistically significant differences in cytochrome c+c1 and a+a3 content were found in mitochondria isolated from the two regions. No significant transmural differences were found in fatty acyl CoA, L-3-hydroxy fatty acyl CoA, succinic and malic dehydrogenase specific activities, whilst isocitric dehydrogenase (NADP) specific activity was significantly higher in mitochondria isolated from the inner layer. In conclusion, the mitochondria isolated from the inner left ventricular layer of the canine heart show a higher oxidative capacity than subepicardial mitochondria. This difference could partly be explained by the higher specific activity of isocitric dehydrogenase in this layer. These properties of subendocardial mitochondria could represent a metabolic support for the greater contractile performance of this layer.
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  • 37
    ISSN: 1435-1803
    Keywords: dihydroergotamine ; underperfused myocardium ; lactate balance ; radiolabelled microspheres ; oxygen consumption
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The study was carried out in 13 mongrel dogs. Regional myocardial blood flow was measured using radiolabelled microspheres. Lactate, H+-ions, and O2 content were measured in arterial and local venous blood. Partial occlusion of the ramus circumflexus (LCX) led to a decrease in left ventricular dp/dt max, systemic arterial pressure, and a marked release of lactate from the underperfused myocardium. With DHE (2 μg/kg infused within 5 min, 8 dogs), a slight decrease in heart rate, left ventricular dp/dt max, LCX-resistance and a small increase in femoral and total peripheral resistance as well as in arterial and left and right atrial pressure was observed. In the normally perfused and in the underperfused part of the left ventricle microsphere assessed blood flow was unchanged or slightly elevated with DHE. Lactate release from the underperfused myocardium was markedly reduced. None of the DHE-induced effects on hemodynamic and metabolic parameters were observed in control experiments with infusion of 0.9% NaCl (5 ml). The results indicate that DHE leads to an amelioration of impaired metabolism in the underperfused myocardium and exerts no vasoconstriction in this area.
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  • 38
    ISSN: 1435-1803
    Keywords: recurrent ischemia ; myocardial metabolism ; high energy phosphates
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Successive ischemic episodes are commonly seen in clinical and experimental cardiology. Although prolonged abnormalities of the canine myocardium have been described following a single ischemic episode, it is not known whether myocardial injury is cumulative following multiple ischemic episodes. Dogs were subjected to three 15-min left anterior descending coronary artery occlusions, each followed by 30 min of reperfusion.In vivo biopsies were obtained for biochemical analysis before and during the first occlusion and 30 min into each reperfusion period. ATP and creatine phosphate (CP) fell in the endocardium during occlusion by 24% and by 69% respectively (both p<.0001). While CP recovered during each reperfusion period, ATP remained significantly depressed. Loss of membrane-permeable purine nucleotide synthesis precursors occurred with the first reperfusion period but not with the second and third reperfusion periods. Therefore, reperfusion following one 15-min coronary occlusion is associated with severe depression of myocardial high energy phosphates; however, two additional occlusions do not cause a further decrease of these substances when intermittent reperfusion is allowed for 30 min.
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  • 39
    ISSN: 1435-2451
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
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  • 40
    ISSN: 1435-2451
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
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  • 41
    ISSN: 1435-2451
    Keywords: Surgical patient ; Fear ; Psychological stress ; Limits of psychological stress ; Chirurgisch Kranker ; Angst ; Psychische Belastung ; Psychische Belastbarkeit
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Der chirurgisch Kranke wird einerseits durch die Furcht vor Schmerzen, andererseits durch die Angst vor Operation und Narkose, letztlich vor dem Tode, psychisch belastet. Exakt definieren lassen sich psychische Belastung und Belastbarkeit noch weniger als die körperliche. Aufgabe des Arztes ist es, die psychische Last des Kranken zu mildern und ihm Vertrauen einzuflößen, aber auch, die Grenzen seiner Belastbarkeit zu erkennen und diese bei der Behandlung zu berücksichtigen.
    Notes: Summary The surgical patient is subjected to psychological stress through fear of pain, operation, anesthesia and finally death. The exact definition of psychic stress and the patient's resistance to it is even more problematic than the definition of somatic stress. It is the doctor's task to alleviate the psychic stress of the patient, to instill confidence and to recognise the limits of his resistance and finally to take all this into consideration in planning his treatment.
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  • 42
    ISSN: 1435-2451
    Keywords: Functional capacity ; Indication for surgical procedure ; Operability ; Belastbarkeit ; Funktionsreserven ; Operationsindikation ; Operabilität
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die somatische Belastbarkeit läßt sich als organbezogene Funktionsreserve definieren. Statistische Untersuchungen haben perioperative Risiken erkennen lassen, die sich in reziprokem Verhältnis zur Belastbarkeit befinden. Zu deren Erfassung wird ein Stufenprogramm von Untersuchungen vor allem der kardialen und pulmonalen Funktion vorgeschlagen, das sich nach dem geschätzten Risiko orientiert. Indikation und Operabilität werden aber besonders in der Tumor- und Alterschirurgie nicht allein von der somatischen Belastbarkeit bestimmt, sondern sind vielfach konditioniert.
    Notes: Summary The somatic functional capacity can be defined as an organ-specific functional reserve. Statistical studies have shown perioperative risks in reciprocal relationship to this limit. A stepwise (graduated) approach for the assessment of cardiac and pulmonary function is suggested, which depends on the estimated risk. Indications for surgical therapy and operability, especially in the treatment of tumors and for geriatric patients, are not only determined by the somatic functional capacity but also by multiple other conditions.
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  • 43
    ISSN: 1435-2451
    Keywords: Polytrauma ; Acute therapy ; Polytrauma ; Akutversorgung
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die Behandlung Schwer- und Mehrfachverletzter erfordert eine exakte Planung und ein ausgereiftes Management. Bewährt hat sich die Einteilung in Akut-, Primär-, Sekundär- und Tertiärphase. In der Akutphase werden alle lebenserhaltenden Maßnahmen durchgeführt. In der Primär-, Sekundär- und Tertiärphase folgen dann die übrigen Eingriffe. Aufgrund einer Untersuchung an 781 Schwerstverletzten haben sich für die Indikationsstellung als wesentliche Parameter der Pulmonalarteriendruck, das Kreatinin, das Bilirubin, die Flüssigkeitsbilanz und das extravasale Lungenwasser herausgestellt sowie der Quotient aus PaO2 und inspiratorischer Sauerstoffkonzentration.
    Notes: Summary Treatment of severely injured patients requires exact planning and mature management. For practical reasons the classification into 4 phases has been introduced: acute, primary, secondary and tertiary phases. During the acute phase all life-saving operations are performed. In the primary, secondary and tertiary phases the procedures vary according to priority. Reviewed on the basis of 781 severely injured patients, the most reliable criteria are: pulmonary artery pressure, creatinine, bilirubin, extravascular lung water, the PaO2/FiO2 quotient and fluid balance.
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  • 44
    ISSN: 1435-2451
    Keywords: Head injuries ; Intracranial haematomas ; Brain edema ; Schädel-Hirn-Verletzungen ; Intrakranielle Blutungen ; Hirnoedem
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Der Erstversorgung von Schädel-Hirn-Verletzten am Unfallort kommt zur Stabilisierung der vegetativen Funktionen große Bedeutung zu. Ursache des letalen Ausgangs ist in vielen Fällen die akute Steigerung des Schädelinnendrukkes. Komplikationen wie arterielle intrakranielle Blutungen und Hirnoedem beeinflussen deshalb die Prognose. Die Möglichkeiten der Frühbehandlung dieser Komplikationen entscheiden über das Transportmittel. An klinischen Beispielen wird dargestellt, welche Bedeutung dem Zeitfaktor bei der Versorgung von Schädel-Hirn-Verletzungen und deren Komplikationen zukommt.
    Notes: Summary Primary care of head injuries at the scene of accident is of major importance for the stabilization of vegetative functions. In many cases death is caused by an acute increase of intracranial pressure. Thus prognosis is influenced by complications like arterial intracranial bleedings or brain edema. The decision on the means of transportation depends on the possibilities of early treatment of these complications. In clinical examples time as a factor in the care of head injuries and their complications are demonstrated.
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  • 45
    ISSN: 1435-2451
    Keywords: Anaesthetic risk ; Risk determination ; Preoperative therapy ; Anaesthesierisiko ; Risikobewertung ; Präoperative Therapie
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Das Operationsrisiko ist ein Komplex aus der Gefährdung durch die Operation und der Gefährdung durch die Anaesthesie sowie zahlreicher Einzelfaktoren, die entweder vom Patienten selbst ausgehen oder von außen auf ihn einwirken. Risiko-Checklisten sind ein Fortschritt in Richtung einer besseren Objektivierbarkeit des Anaesthesie- und Operationsrisikos. Es ist aber nicht nur eine verbesserte Risikoerfassung anzustreben, sondern gleichzeitig sind die Möglichkeiten zur präoperativen Optimierung der Homöostase (insbesondere Atmung, Kreislauf und Ernährungszustand) auszuschöpfen, um die Grenzen der Belastbarkeit weiter hinauszuschieben und damit den Sicherheitsspielraum für Anaesthesist, Operateur und Patient zu erhöhen.
    Notes: Summary The overall operative risk is determined by operation, anaesthesia and numerous additional factors which include the pre-existing physical status of the patient himself as well as external impacts. Check-lists have improved the validity of predicting these risks. However, evaluation of the operative risk is not the only prerequisite for extending the limits of the patient's stress endurance and expanding consecutively the margins of safety for the anaesthesist, surgeon and patient. Additionally, an optimal homoeostasis has to be achieved preoperatively with emphasis on respiration, circulation and nutritional status.
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  • 46
    ISSN: 1435-2451
    Keywords: Hemo- and pneumothorax ; Intrathoracic injuries ; Traumatic flailchest ; Atmungs- und Kreislaufbedrohung ; Hämo- und Pneumothorax ; Intrathorakale Organverletzung
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die Belastbarkeit des Patienten nach Thoraxtraumen wird durch die erforderlichen, wenig eingreifenden und einfachen diagnostischen und therapeutischen Maßnahmen nicht tangiert. Wegen der vitalen Bedrohung sind sie immer indiziert. Neben der klinischen Untersuchung ist die wichtigste diagnostische Maßnahme die einfache Thorax-Röntgenübersichtsaufnahme im p.a.-Strahlengang bei aufgerichtetem Oberkörper. Im Falle eines Hämo- und/oder Pneumothorax wird eine Pleuradrainage unter Lokalanaesthesie eingelegt, die durch Ableitung von Luft und/oder Blut die Expansion der Lunge ermöglicht. Ein Spannungspneumothorax ist durch Punktion oder Pleuradrainage zu behandeln. Bei instabilem Thorax kommt als lebensrettende Maßnahme ausschließlich die Intubation mit künstlicher Beatmung in Frage. Bei schwerer intrathorakaler Blutung, ob aus der Lunge, Herz oder den großen Gefäßen, muß die Operation zwecks Beherrschung der Blutung erfolgen.
    Notes: Summary After clinical investigation the most important diagnostic procedure is the simple chest X-ray in upright position. In case of hemothorax or pneumothorax the insertion of a large chest tube in the third of fourth intercostal space is necessary. Patients with traumatic flail chest and paradoxical respiration need first of all immediate intubation and artificial respiration, afterwards operative stabilization is beneficial in selected patients. In case of severe intrathoracic hemorrhage and in case of injuries of the lungs, heart and great vessels an active surgical approach is a life-saving treatment. Apart from patients with very bad general condition the usual diagnostic measures and an adequate conservative or surgical treatment can always be tolerated by the patient considering his life-threatening condition.
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  • 47
    ISSN: 1435-2451
    Keywords: Closed and open fractures ; Loss of blood ; Crush-syndrome ; Geschlossene und offene Frakturen ; Volumenmangel ; Crush-Syndrom
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Bei Frakturen der unteren Extremitäten ist stets ein hoher Blutverlust zu berücksichtigen. Schon vor und während der spezifischen Diagnostik sollte eine adäquate Volumensubstitution erfolgen. Die Diagnostik soll ohne Umwege zügig nur so weit erfolgen, wie sie für die therapeutische Handlung notwendig ist. Die operative Stabilisierung geschlossener Frakturen kann als Wahleingriff auf einen optimalen Zeitpunkt festgelegt werden. Die sofortige Stabilisierung des offenen Bruchs hat sich nicht nur zur Kontrolle der Blutung, sondern vor allem zur Bewahrung der Weichteile vor weiterer Zerstörung und Infektion bewährt. Zermalmung, Ausrißverletzung und traumatische Amputation gefährden auch als isolierte Verletzungen durch Crush-Syndrom das Leben des Patienten.
    Notes: Summary In bone fractures in the lower extremities a high blood loss must be taken into consideration. An adequate blood transfusion should be given before and during diagnostic procedures. Diagnostic measures should proceed quickly and be limited to the necessary treatment. Operative setting of closed fractures can be programmed when conditions are optimal. Immediate setting of open fractures has proven to be valuable not only because the blood loss may be controlled, but also because extensive soft tissue distraction and possible infection can be prevented. The crush-syndrome can be caused by crushing injuries, pluck-out injuries and traumatic amputation and endanger the patient's life.
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  • 48
    Electronic Resource
    Springer
    Langenbeck's archives of surgery 364 (1984), S. 107-109 
    ISSN: 1435-2451
    Keywords: Stability ; Instability ; Early osteosynthesis ; Stabilität ; Instabilität ; Rechtzeitige Osteosynthese
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Bei Verletzungen der Wirbelsäule muß zwischen Stabilität und Instabilität unterschieden werden. Stabile Brüche werden funktionell behandelt, bei instabilen muß unterschieden werden, ob mit den üblichen konventionellen Maßnahmen eine befriedigende Stellung erreicht werden kann. Um jeden Preis sollten stärkere Achsenfehler oder chronische Instabilitäten vermieden werden. Möglichst frühzeitig sind Osteosynthese-Verfahren zu empfehlen, wenn abzusehen ist, daß die konservativen Maßnahmen nicht zum Ziel führen. Durch technische Standardisierung der Operationstechniken kann das Risiko gering gehalten werden.
    Notes: Summary Spinal injuries must be divided into stable and unstable lesions. Stable fractures are treated functionally, in unstable cases a decision must be made whether conventional treatment will be satisfactory. Severe kyphosis or chronic instability must be avoided. Open reduction and spinal fusion are recommended very early, if conventional therapy is not successful. Surgical risks are minimized by technical standards.
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  • 49
    ISSN: 1435-2451
    Keywords: Blunt abdominal trauma ; Operative strategy ; Belastbarkeit ; Bauchtrauma bei Polytrauma
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Das operationsbedürftige Bauchtrauma stellt in der Kombination mit Verletzungen anderer Körperbereiche noch immer eine in erheblichem Maße lebensbedrohende Verletzung dar, die trotz intensiver Bemühungen über ein Mehrorganversagen vor allem im höheren Lebensalter mehrere Tage postoperativ zum Exitus führen kann. Eine initiale Beachtung des Erhalts der funktionellen Residualkapazität durch situationsangepaßte atemtherapeutische Maßnahmen ist eine der wesentlichsten Voraussetzungen zur Verbesserung der Behandlungsergebnisse.
    Notes: Summary Abdominal trauma in combination with other injuries continues to be a life-threatening risk. In spite of intensive care multiple organ failure can result in death several days postoperatively. The initial respiratory therapy of the injured patients is of outstanding importance to ameliorate the unsatisfying results.
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  • 50
    ISSN: 1435-2451
    Keywords: Gastric cancer ; Risks ; Surgical indications and tactics ; Pre- and postoperative measurements ; Magencarcinom ; Risiken ; Operationsindikation und -taktik ; Präund perioperative Maßnahmen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Magenkrebsoperationen sind mit großen Belastungen und Risiken für den Patienten verbunden. Diese Risiken sind abhängig von Lokalisation und Ausdehnung des Tumors, vom Allgemeinzustand des Patienten (Ernährungs- und Immunstatus), vom Alter, von Zweiterkrankungen und der Größe der notwendigen Operation. Hierbei sind die Prinzipien der Radikalität gegen die Belastungsfähigkeit des Patienten abzuwägen, vor allem beim alten Menschen. Umfangreiche diagnostische Maßnahmen sind zur Risikoerkennung notwendig. Der Operationsvorbereitung (Hyperalimentation), der abgewogenen Indikationsstellung und risikogerechten Operationstaktik sowie perioperative Maßnahmen kommt große Bedeutung zu, um die Belastung und das Risiko für den Patienten zu begrenzen.
    Notes: Summary Patients with gastric cancer undergoing surgery have much to endure and are accompanied by many risks. These risks depend on localization and extent of the tumor, the patients' general condition (nutritional and immune status), age, coexistent diseases and the extent of the required operation. In view of these facts, the principle of radical surgery must be weighed against the tolerance capability of the patient, especially in old people. Extensive diagnostic procedures are necessary to explore those risks. The preoperative treatment (hyperalimentation), the well considered indication for surgery, the choice of operation with lowest risk and the perioperative measurements are of great importance in limiting the risk for the patient.
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  • 51
    ISSN: 1435-2451
    Keywords: Pancreatic carcinoma ; Obstructive jaundice ; Duodeno-pancreatectomy ; Pankreascarcinom ; Verschlußikterus ; Duodenopankreatektomie
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die Belastbarkeit des Pankreascarcinom-Patienten wird in 4 Phasen geprüft: in derDiagnostik, wo zunächst noninvasive Verfahren Vorfahrt haben; in derVorbehandlung, wo die primäre Entlastung der Gallenwege beim Ikteruspatienten keine Vorteile zu bringen scheint, bei derIndikationsstellung, die letztlich eine Resektionsquote von nur 13% ergibt, und bei denTherapieergebnissen, wo die Hospitalletalität bei 200 Duodenopankreatektomien 2,5% beträgt.
    Notes: Summary The patient with pancreatic carcinoma is tested in 4 phases: duringdiagnosis the non-invasive procedures take precedence; as regardspre-operative treatment, primary biliary decompression seems to bring no advantages in the icteric patient; theindications for various treatment forms show a resectability rate of only 13%; the final test is the mortality rate of thetreatment selected: in 200 duodenopancreatectomies it amounted to 2.5%.
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  • 52
    ISSN: 1435-2451
    Keywords: Haemorrhage ; Gastroduodenal ulcera ; Blutendes Ulcus duodeni et ventriculi
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Aus dem Zeitraum der letzten 15 Jahre werden 448 Patienten mit schwerer Blutung aus einem Ulcus ventriculi sive duodeni vorgestellt. In 3 Zeitperioden änderten sich Indikation, Organisation und Methodenwahl. Insbesondere kamen die endoskopische Diagnostik und Therapie mit guten Ergebnissen hinzu. Durch die Endoskopie erfolgte eine negative Auswahl für diese chirurgische Blutstillung, so daß die chirurgischen Leistungszahlen deprimiert wurden. Nach wie vor gilt die Forderung nach der Frühindikation und dies auch bei zusätzlicher Belastung.
    Notes: Summary 448 patients with severe haemorrhage from gastroduodenal ulcera during the last 15 years are presented. Within this period indication, organisation and the choice of method have changed in 3 phases. Included are the endoscopic diagnosis and treatment with very good results. As a result of endoscopy there is a negative selection of patients for surgery causing a depression of the results after surgical treatment. The propagation for early indication even in high risk patients still has validity.
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  • 53
    ISSN: 1435-2451
    Keywords: Ileus ; Diagnosis ; Treatment ; Ileusdiagnose ; Behandlung ; Patientenbelastung
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die Ileuskrankheit ist charakterisiert durch eine rasche Progredienz. Deshalb muß die Diagnose schnell gestellt und die Therapie rasch eingeleitet werden. Die Diagnose des Ileus selbst kann durch einfache Methoden gestellt werden, die den Patienten nicht belasten. Die Lokalisationsdiagnose und die Feststellung der Ätiologie der Darmobstruktion können für den Patienten jedoch eine erhebliche Belastung darstellen. Röntgenuntersuchung und Endoskopie haben sich als effektive Methoden erwiesen und können deshalb in besonderen Fällen empfohlen werden. Operative Maßnahmen müssen dem Allgemeinzustand des Patienten angepaßt werden.
    Notes: Summary This disease caused by intestinal obstruction progresses rapidly. Therefore diagnosis and therapeutic procedures have to be performed quickly. Whereas the diagnosis of the ileus itself can be made by simple methods which do not discomfort the patient, diagnosis of localization and etiology of bowel obstruction causes considerable strain for the patient. Nevertheless X-ray investigations and endoscopy have proved to be effective. Therefore these methods can be recommended in special cases. Operative procedures of ileus treatment have to be adapted to the patient's condition and cannot be generally recommended.
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  • 54
    Electronic Resource
    Springer
    Langenbeck's archives of surgery 364 (1984), S. 163-169 
    ISSN: 1435-2451
    Keywords: Portal hypertension ; Hepatic perfusion ; Oesophageal varices ; Shunt surgery ; Endoscopic sclerosation ; Portale Hypertension ; Leberdurchblutung ; Oesophagusvaricen ; Shuntchirurgie ; Endoskopische Sklerosierung
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die häufigste Ursache der portalen Hypertension ist der intrahepatische präsinusoidale Block bei (alkoholischer) Lebercirrhose. Für diese Patienten stellt jeder chirurgische Eingriff eine schwere Belastung dar, hat doch die Cirrhose von sich aus einen eigenständigen, kaum zu beeinflussenden Verlauf. Die laborchemischen und haemodynamischen Prognosekriterien sind nur bedingt aussagefähig. Speziell im Akutfall kommt der klinischen Beurteilung des Allgemeinzustandes, Ernährungszustandes, des Alters sowie von Dekompensationszeichen wie Encephalopathie, Ikterus und Ascites heute immer noch größte Bedeutung zu, wobei zusätzlich als günstiger Prognosefaktor ein mehr oder minder normales Lebervolumen mit einem Perfusionsindex nahe von 1 gilt.
    Notes: Summary The most frequent cause of portal hypertension is the intrahepatic presinusoidal block in (alcoholic) liver cirrhosis. Every surgical intervention is a great stress for these patients, since it is very difficult to influence the course of cirrhosis itself. Laboratory chemistry and haemodynamical prognostic criteria are of limited value only. Especially during the acute stage clinical evaluation of the patient's general and nutritional condition, age, as well as signs of decompensation such as encephalopathy, icterus and ascites are still of greatest importance. A more or less normal volume of the liver and a perfusion index of approx. 1 is regarded to be a favourable prognostic factor.
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  • 55
    ISSN: 1435-2451
    Keywords: Due diligence ; Standard of care ; Erforderliche Sorgfalt ; Standard der Medizin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Das Recht verlangt vom Arzt die „erforderliche Sorgfalt” bei der Behandlung. Die Judikatur verweist dafür auf den dem Arzt bei zumutbaren Anstrengungen verfügbaren Stand der medizinischen Wissenschaft. Abzustellen ist auf den durchschnittlich sorgfältigen Arzt. Der Standard enthält normative und tatsächliche Elemente: „die gute ärztliche Übung”. Es stellt sich aber die Frage, wer den Standard für die Felder der chirurgischen Tätigkeit bestimmt. Das Recht verweist auf die medizinische Wissenschaft, setzt aber Mindesterfordernisse. Der bisherige Standard hindert nicht die Erprobung eines neuen Verfahrens mit zumutbaren Risiken.
    Notes: Summary German law requires “due diligence” of the physician. The courts refer to the state of medical science that is available to a physician who makes every reasonable effort to obtain it. The relevant qualification is to be the skill of an “average” physician. The standard contains normative and factual elements: “good medical practice” The question, however, arises, who establishes thestandards for the fields of surgery. The law refers to medical science but lays down minimum requirements. The prevailing standard does not prevent new techniques from being tested, but when they become the standard, cannot be determined in general.
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  • 56
    ISSN: 1435-2451
    Keywords: Intracranial nerve grafting ; Intrakranielle Nerventransplantation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Bei raumfordernden Prozessen des Kleinhimbrückenwinkels und des inneren Gehörganges gelingt es, mit verfeinerter mikrochirurgischer Technik in mehr als 90% der Fälle eine radikale Entfernung des N. facialis zu erreichen. Bei Nichterhaltung bzw. Traumen des N. facialis bietet sich die Nervennaht bzw. Nerventransplantation an. Durch die intrakraniell-intratemporale Nerventransplantation, die wir anstelle der Dottschen Operation im Jahre 1975 eingeführt haben, konnten wir bei einem großen Krankengut sehr zufriedenstellende Ergebnisse erzielen.
    Notes: Summary In space-occupying processes of the cerebellopontine angle and internal auditory canal, total removal with preservation of the facial nerve can be achieved in more than 90% of the cases by means of advanced microneurosurgical techniques. In cases of nonpreservation or traumata of the facial nerve, neurosurgery offers end-to-end-suture or nerve grafting. Intracranial-intratemporal nerve grafting was introduced here in 1975 (instead of the Dott technique), and our results have proved to be very satisfactory in a great number of patients.
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  • 57
    ISSN: 1435-2451
    Keywords: Wound infection ; Early recognition ; Determination of lysozyme ; Wundinfektion ; Früherkennung ; Lysozymbestimmung
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Auf der Suche nach objektivierbaren Frühkriterien einer sich anbahnenden Wundinfektion hat sich uns von allen untersuchten Parametern die Bestimmung des Lysozymgehaltes im Wundsekret als zuverlässigste Methode zur Früherkennung einer Wundinfektion bislang bewährt. Auch wenn die zu geringe Fallzahl eine abschließende Beurteilung noch nicht erlaubt, scheint sich doch in der Lysozymbestimmung eine neue vielversprechende Möglichkeit zur Früherkennung einer Wundinfektion abzuzeichnen.
    Notes: Summary In search of measurable early criterions of a beginning wound infection the determination of lysozyme content in wound secretion has so far proved to be the most reliable method for early recognition of wound infection. Even if the small number of cases does not yet allow a concluding critical examination, the determination of lysozyme content seems to be a new important possibility for early recognition of wound infection.
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  • 58
    ISSN: 1435-2451
    Keywords: Wound healing impairment ; Wound hypoxia ; TCDO ; Oxygen carrier ; Gestörte Wundheilung ; Wundgewebehypoxie ; TCDO ; Sauerstoffträger
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die hervorragende Wirkung des neuen biokatalytisch aktivierbaren Sauerstoffträgers TCDO (Tetrachlordecaoxid — Oxyferin®) beruht auf der wirksamen Beeinflussung der Gewebehypoxie. Die Ergebnisse einer erstmals in der Wundbehandlung durchgeführten randomisierten Doppelblindstudie gegen 0,9% NaCl bestätigen diese Wirksamkeit objektiv (n = 38). Den klinischen Stellenwert dokumentieren die Ergebnisse einer randomisierten Einfachblindstudie (n = 58) gegen die derzeit beste lokale Standardtherapie — eine Prüfung auf Überlegenheit. In beiden Studien wurden die Kriterien der Wundheilung „Verbesserung des Verschmutzungsgrades, Ausbildung einer gesunden Granulation und Epithelisierung der Wundoberfläche” täglich protokolliert und statistisch ausgewertet. Die hochsignifikante Überlegenheit von TCDO-Lösung, in der Behandlung der gestörten Wundheilung wird auch durch eine planimetrische Auswertung bestätigt.
    Notes: Summary The high therapeutic efficiency of the biocatalytically activated oxygen carrier TCDO (tetrachlorodecaoxide — Oxoferin®) is based on its effect on wound tissue hypocia. This is confirmed by the results of a randomised double blind trian (n = 38) against physiological saline carried out for the first time in the field of wound treatment. The clinical value is also documented by the results of a single blind randomised trial (n = 58) against the most appropriate standard local treatment — a demonstration of superiority. In both studies the criteria of wound healing, “improvement of wound contamination, formation of a sound wound granulation tissue, epithelisation of the wound surface” were daily recorded and analysed statistically. The highly significant superiority of the TCDO-solution in the treatment of impaired wound healing is also confirmed by planimetrical measurements.
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  • 59
    ISSN: 1435-2451
    Keywords: Silastic foam ; Disturbances in wound healing ; New dressing method ; Silasticschaum ; Schlecht heilende Wunden ; Neue Verbandsmethode
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Es wird über eine neuartige Verbandsmethode mit Silikonschaum berichtet, die bei 55 Patienten mit gutem Erfolg angewendet wurde. Sie ist bei schlecht heilenden und infizierten Wunden, besonders bei Diabetikern und Arteriosklerotikern indiziert. Durch die physikalische Beschaffenheit des Silikonschaumverbandes kommt es zu einer schnellen Wundreinigung und Abheilung. Die vorgestellte Behandlungsmethode stellt eine gute Alternative zu den konventionellen Verbandsmethoden dar. An 2 Fällen wird der Behandlungserfolg mit Silikonschaumverbänden demonstriert.
    Notes: Summary This report deals with new dressing method using silastic foam which was used on 55 patients with good success. Silastic foam dressings are indicated in cases of badly healing and infected wounds, especially caused by diabetes and arteriosclerosis. On account of the physical quality of the silastic foam the wounds were cleaned and healed quickly. The treatment with silastic foam dressing is a good alternative to conservative dressing methods. Two cases will demonstrate the success of the silastic foam dressing in surgery.
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  • 60
    ISSN: 1435-2451
    Keywords: Recurrent ulcer ; Conversion operations ; Complications ; Magenresektion ; Ulcusrezidiv ; Korrektureingriffe ; Komplikationen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Bei 131 Patienten mit Umwandlungsresektion war der ulcusbedingte Ersteingriff bei 75% eine BII-Resektion. Indikation zur Korrekturoperation war beim BI in 90% ein Rezidivulcus, beim BII jedoch in 25% funktionelle Störungen. Beim BII waren die Rezidivulcera häufiger durch Penetration, Perforation und Blutung kompliziert. Schwere Komplikationen waren in 20% und in 10% ein letaler Ausgang die Folge. Bemerkenswert war, daß die Letalität nach BII-BI-Umwandlung deutlich über der nach BI-Nachresektion oder BI-BII-Umwandlung lag. In Kenntnis des hohen Operationsrisikos sollte als Alternative zur Behandlung des Rezidivulcus an die thorakale trunculäre Vagotomie gedacht werden.
    Notes: Summary In 131 patients with gastric conversion operations, the primary resection was performed in 75% according to the Billroth II method. The indication for the conversion operation after BI resection was a recurrent ulcer in 90%, whereas functional disorders after BII were the reason for reintervention in 25%. In BII, recurrent stomach ulcers were more often complicated by penetration, perforation, and bleeding than in BI. Serious complications resulted in 20% and lethality was nearly 10%. It was noted that lethality was higher after BII-BI conversion than after BI re-resection and BI–BII conversion. Because of the high operative risks the thoracal truncal vagotomy should be considered as an alternative treatment.
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  • 61
    ISSN: 1435-2451
    Keywords: Peptic ulcer surgery ; Emergency operation ; Cimetidine ; Lethality ; Ulcus pepticum ; Chirurgische Therapie ; Cimetidin ; Letalität
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die chirurgische Behandlung des primären Ulcus pepticum ist in Mannheim seit 1973 standardisiert und unverändert. In 10 Jahren (1974–1983) werden 1207 Ulcusoperationen durchgeführt: vor Einführung des Cimetidin (November 1977) 150 Operationen im Jahr, danach jährlich nur noch 100. Die Zahl der Notfalleingriffe schwankt gleichbleibend zwischen 30 und 50/Jahr: damit steigt auf Kosten der elektiven Eingriffe der relative Anteil der Notoperationen von 33% auf zuletzt 60%. Die Gesamtletalität der Ulcusoperierten bleibt über die Jahre mit 7,7% konstant: trotz sinkender Letalität der Notfalleingriffe (20% → 16%) erklärt sich dies durch die starke relative Zunahme der Notoperationen. Die Suche nach dem komplikationsgefährdeten Ulcuspatienten sollte intensiviert werden, um ihn elektiv zu operieren!
    Notes: Summary There has been a standardized surgical regimen tot peptic ulcer patients in Mannheim since 1973. From 1974 to 1983, 1,207 ulcer operations have been formed: before cimetidine (introduction in November 1977) there were 150 annually; since 1978 there have been only 100 per year. The number of emergency operations has remained fairly constant — between 30 and 50 per year: thus the relative percentage has risen from 33% to 60%. The overall lethality of 7.7% has not changed over the years despite the decreasing lethality of emergency operations (20% to 16%). However this positive effect is compensated by the increasing percentage of emergencies. Complication-prone ulcer patients should be identified and operated upon electively.
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