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Results 451 - 500 of 725
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Tarn D M - - 1996
This study examines whether electroretinogram recovery after short-term (15- or 20-min) ischemia is enhanced by agents (catalase and dextromethorphan) that are known to enhance recovery after longer (60-75 min) periods of ischemia. Under both light-adapted and dark-adapted conditions, Dutch rabbits were exposed to two sequential sets of short-term ischemia, each ...
Gutierrez G - - 1995
In many critically ill patients, systemic measures of hemodynamic and O2 transport variables may not be sufficiently sensitive to portray the complex interaction between energy requirements and energy supply in all tissues. Gastric or intestinal tonometry has been proposed as a relative noninvasive index of the adequacy of aerobic metabolism ...
Daxnerová Z - - 1995
Ischemia and reperfusion-induced nuclear and nucleolar changes of the lumbosacral dorsal root ganglia neurons were studied in a spinal cord ischemic model of a rabbit. Twenty and forty min abdominal aorta ligation followed immediately by perfusion fixation, 20 min abdominal aorta ligation followed by 1 h of normoxic reoxygenation and ...
Block F - - 1994
The present study investigated whether flupirtine attenuates the depression and enhances the recovery of the b-wave of the electroretinogram (ERG) in response to retinal ischaemia. The ERG was recorded from pentobarbital-anaesthetized rats before, during and after transient (24 min) occlusion of both common carotid arteries. Flupirtine administered 20 min before ...
Portegies M C - - 1994
Recent studies strongly support the prognostic importance of transient silent ischemia. Because patients with silent ischemia are at higher risk of a cardiac event, they are likely to benefit not only from control of symptoms, but also from treatment directed at prevention of ischemia. The efficacy of controlled-release metoprolol 200 ...
van der Lee C - - 1994
St Thomas' Hospital cardioplegic solution is commonly used to arrest hearts during surgery. Pursuing the hypothesis that the cardioprotective properties of adenosine could be a beneficial adjunct to a solution containing high K+ and Mg2+, we tested a low and a high adenosine concentration added to this cardioplegic solution, aiming ...
Friesenecker B - - 1994
Ischemia-reperfusion injury was investigated in terms of functional capillary density (FCD), capillary red blood cell velocity (cRBCv), and arteriolar and venular diameter after 4-h ischemia in the unanesthetized hamster skin-fold preparation. Animals in group 1 were studied by transillumination. Group 2 received a bolus injection of fluorescein isothiocyanate (FITC)-dextran (mol ...
Gottdiener J S - - 1994
OBJECTIVES: This study examined the relations among the triggers of ischemia during the activities of daily life, mental stress-induced ischemia in the laboratory and functional severity of ischemia on exercise testing. BACKGROUND: Myocardial ischemia is readily induced with exercise testing, but most episodes of ischemia in daily life occur during ...
Yasutake M - - 1994
Activation of sarcolemmal Na+/H+ exchange has been proposed as a causal factor in reperfusion arrhythmogenesis. To test this hypothesis, we determined the antiarrhythmic efficacy of two structurally distinct but equipotent Na+H+ exchange inhibitors, 5-(N-ethyl-N-isopropyl)amiloride (EIPA) and the novel drug, 3-methylsulfonyl-4-piperidinobenzoyl guanidine (HOE-694), in isolated rat hearts (n = 12/group) subjected ...
Girvan R J - - 1994
Acute dysvascular limb in young adults is a rare entity. Diagnosis is often difficult because symptoms are not recognized as ischemic. The most common causes of this condition are premature atherosclerosis, thromboangiitis obliterans, microemboli, popliteal entrapment syndrome, collagen vascular disease, Takaysu's arteritis, and coagulopathy. A case study is presented to ...
Tanioka Y - - 1994
Rewarming ischemic injury during vascular anastomosis severely compromises posttransplant pancreas graft survival because the graft has already been subjected to warm and cold ischemia before vascular anastomosis. We examined whether preservation of the pancreas graft by the two-layer method ameliorates rewarming ischemic injury of the graft during vascular anastomosis and ...
Kiliç S - - 1994
The haemodynamic effects of different dosages of adenosine were studied using colour flow Doppler sonography (CFDS) in 33 men, whose penile vascular bed responded well to papaverine. In six cases, we injected 25, 50, 100, 250 micrograms dosages of adenosine intracavernously at 15 min intervals and no erection occurred. However, ...
Yanamoto H - - 1994
The possible role of the immune-defense system in the development of cerebral vasospasm after subarachnoid hemorrhage (SAH) was investigated in rabbits. We used a synthetic serine protease inhibitor, gabexate mesilate (GM), a glucocorticoid, betamethasone sodium phosphate (B-P), and an immunosuppressant, ciclosporin (Cyclosporin A, CYA), to prevent cerebral vasospasm. These agents ...
Churchill T A - - 1994
The current study was undertaken so that the effects of both ischemia and ischemia + hypothermia could be examined in mammalian liver. Particular reference was made to the function of glycolysis, which is the only mechanism for energy production under these conditions. The response of adenylate pools reflected the energy ...
Pasnani J S - - 1994
Pro- and antiarrhythmic effects of dl-sotalol and d-sotalol were compared with their electrophysiological actions in an isolated tissue model of simulated ischemia and reperfusion. Microelectrode recordings were made from endo- and epicardium of isolated guinea pig right ventricular free walls. An electrocardiogram also was recorded by two electrodes at opposite ...
Hudspeth D A - - 1994
This study tests the hypothesis that the adenosine deaminase inhibitor pentostatin (2-deoxycoformycin), when given before ischemia or during infusions of blood cardioplegia, augments interstitial adenosine levels and prevents postcardioplegia dysfunction in hearts with antecedent ischemia. Twenty-one anesthetized dogs were placed on cardiopulmonary bypass, and the hearts were made globally ischemic ...
Herkes S M - - 1994
BACKGROUND: Our aim was to assess changes in transport of water and electrolytes under basal, proabsorptive, and prosecretory conditions after an in situ neural isolation of the jejunoileum. METHODS: Eight dogs underwent intraoperative perfusion of 50 cm of jejunum with a balanced electrolyte solution during sham operation and after neural ...
Ikeda H - - 1994
To explore the role of calcium-dependent protease in the stunned myocardium, open-chest dogs underwent 15 min of left anterior descending coronary artery occlusion followed by 2 h of reperfusion. Dogs received a single bolus intravenous injection of either the protease inhibitor NCO-700 (n = 6) or saline (n = 6) ...
Tominaga T - - 1994
To detect if nitric oxide (NO) is produced in rat forebrain ischemia, we applied an electron paramagnetic resonance (EPR) NO-trapping technique. We also performed a detailed characterization of the technique. Diethyldithiocarbamate (DETC) and Fe-citrate were used as NO-trapping reagents. Under controlled ventilation, forebrain ischemia was produced by occlusion of both ...
Ring J A - - 1994
We have developed an in situ isolated perfused fetal sheep liver preparation to study fetal hepatic function free from the confounding influences of the mother and other fetal organs, and we have used the preparation to study the fetal hepatic clearance and biliary excretion of sodium taurocholate (TC). The viability ...
Swenson E S - - 1994
The absorption of the polar drug phenol red was assessed in a rat intestinal perfusion model, in the presence of a variety of potential intestinal permeability enhancers. Both the absorption rate constant KA and the plasma phenol red concentration were measured. Perfusates were also assayed for the presence of lactate ...
Demaison L - - 1994
The influence of cardiac stunning on the oxidation of fatty acids and the oxidative phosphorylation in mitochondria was investigated. Rat hearts were perfused for 15 min according to the working mode with a Krebs-Henseleit buffer containing glucose (11 mM). The hearts were then maintained in normoxic conditions (C group) or ...
Kaplan L J - - 1994
The mechanisms by which ischemic preconditioning (IPC) protects against reperfusion (RP) injury are unknown. The purpose of this study was to relate IPC to postischemic mechanical function, vascular reactivity, and bioenergetics. Isolated perfused rat hearts were randomized to two groups. Control (CTRL) hearts underwent 25 min of global, 37 degrees ...
Ray C A - - 1994
Previous studies suggested that endogenous opiates may attenuate the cardiovascular and sympathetic adjustments to static exercise. We tested whether this effect originates from exercising skeletal muscle. Eight men performed 2 min of static handgrip (30% maximum) followed by 2 min of posthandgrip muscle ischemia after three interventions: 1) control, 2) ...
Moolman J A - - 1994
It has recently been shown that hypoxia and ischemia are equally effective to precondition the myocardium of the rat. A comparison of the metabolic changes caused by transient ischemia and hypoxia has not yet been made and may help to elucidate the metabolic factors involved in eliciting preconditioning. The aim ...
Schiariti M - - 1994
Guinea-pig ventricular myocardium was partly exposed to normal Tyrode's superfusion and partly to altered conditions (using modified Tyrode's solution) set to simulate acute myocardial ischemia (PO2 80 +/- 10 mmHg; no glucose; pH 7.00 +/- 0.05; K+ 12 mM). Using a double-chamber tissue bath and standard microelectrode technique, the occurrence ...
Lasley R D - - 1994
The purpose of this study was to determine the role that adenosine plays in enhanced myocardial preservation during cold storage with the University of Wisconsin solution. Hearts from adult rabbits were flushed with University of Wisconsin solution with or without adenosine and stored at 4 degrees C for 24 hours. ...
DeBehnke D - - 1994
STUDY OBJECTIVE: The objective of this study was to determine the time limits of resuscitation following increasing intervals of untreated pulseless electrical activity using cardiopulmonary bypass as the resuscitation tool. DESIGN: Prospective controlled laboratory investigation using a canine model of pulseless electrical activity. SUBJECTS: 20 mechanically ventilated mongrel dogs of ...
Albertine K H - - 1994
Endothelial cell dysfunction and cardiac myocyte injury resulting from ischemia and reperfusion have been associated with accumulation of neutrophils in the myocardium. To determine whether the accumulation is related primarily to intravascular sequestration or extravascular infiltration of neutrophils during the early period of reperfusion, we morphometrically quantified the tissue distribution ...
Vieira M A - - 1994
Isolated rat kidneys were perfused with T-kinin (TK, Ile-Ser-BK) and bradykinin (BK). HPLC analysis of perfusate samples taken at 2-10 min during the TK perfusion (0.5 nmol/mL initial concentration) showed two peptide peaks, the first one eluting at 14.42 min, the same retention time for standard BK, and the second ...
Sundqvist K E - - 1994
It has been suggested that propionyl-L-carnitine administration to ischaemic hearts facilitates the restoration of cardiac function upon reperfusion, but it is still a matter of dispute whether its effect is conveyed via the metabolic effect of the propionyl moiety, the carnitine moiety or other mechanisms involving membrane receptor interactions. The ...
Massoudy P - - 1994
We investigated the role of bradykinin (BK) in cardioprotection elicited by angiotensin-converting enzyme (ACE) inhibition is isolated guinea pig heart performing pressure-volume work. Cardiac output (CO), coronary blood flow (CBF), and external heart work (EHW) were determined before and after ischemia and reperfusion (15 min each). Furthermore, the glutathione (GSH) ...
Shimazaki K - - 1994
The distribution of inositol 1,4,5-triphosphate 3-kinase (IP3 3-kinase) in the gerbil hippocampus was studied before and after transient ischaemia, by immunohistochemistry and immunoblot with monoclonal antibody to IP3 3-kinase. In control gerbils, intense IP3 3-kinase immunoreactivity was localized in the dendritic field of CA1 pyramidal neurones. However, after ischaemia for ...
Deedwania P C - - 1994
Although silent ischemia is common in patients with stable coronary artery disease (CAD), controversy surrounds the issue regarding the most appropriate method for detection. Routinely performed exercise tolerance testing provides important prognostic information. However, ambulatory electrocardiographic monitoring (AEM) has the distinct advantage of enabling evaluation of silent ischemia during daily ...
Barone F C - - 1994
Endothelin-1, a peptide exhibiting extremely potent cerebral vasoactive properties, is elevated in the cerebrospinal fluid after hemorrhagic stroke and implicated in cerebral vasospasm. The purpose of this study was to determine changes in endothelin in ischemic rat brain by assaying endothelin tissue and extracellular levels. Immunoreactive endothelin levels in ischemic ...
Broadley K J - - 1994
The role of endogenous adenosine during the beta-adrenoceptor responses to isoprenaline of guinea-pig isolated cardiac preparations was examined. Insignificant effects of adenosine deaminase (0.3 U.mL-1) on cumulative concentration--response curves for isoprenaline on isolated left and right atria and papillary muscles indicated a negligible depressant effect of endogenous adenosine during these ...
Hull S S SS - - 1994
Seven conscious dogs documented to be at high risk by the occurrence of ventricular fibrillation (VF) during acute myocardial ischemia were randomly assigned to 6 weeks of either daily exercise training or cage rest followed by exercise training. After 6 weeks of daily treadmill training, heart rate variability, a marker ...
Allen B T - - 1994
The metabolic and neurologic functional effects of regional hypothermia induced by cold (4 degrees C) heparinized saline perfusion on spinal cord ischemia were evaluated in 35 rabbits. Spinal cord ischemia was induced for 20 minutes by infrarenal aortic occlusion in anesthetized animals. Regional spinal cord hypothermia was obtained by perfusing ...
Müller T B - - 1994
The new non-NMDA (N-methyl-D-aspartate) receptor antagonist NBQX (2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo(F)quinoxaline) has previously been shown to exert a neuroprotective effect in animal models of cerebral ischemia when administered in the post-ischemic phase. In this investigation the effect of NBQX on acidosis and energy recovery in early reperfusion after 10 min of transient forebrain ...
Himmelreich G - - 1994
Leukocytes play an important role in the development of disseminated intravascular coagulation (DIC). In the reperfusion phase of OLT a DIC-like situation has been described and has been held responsible for the high blood loss during this phase. We investigated the role of leukocytes in the pathogenesis of DIC in ...
Kuroda Y - - 1994
We have demonstrated that adenosine triphosphate (ATP) is synthesized within a canine pancreas during preservation by the two-layer method and there is a direct correlation between a high ATP tissue level and good posttransplant outcome. The purpose of this study was to examine the difference in energy metabolism between fresh ...
Parker D A - - 1994
Slices of pulp from human maxillary and mandibular molar and promolar teeth were incubated with [3H]-noradrenaline (0.2 mumol/l) for 30 min after which the [3H]-noradrenaline and [3H]-metabolites in the tissue and medium were assayed by column chromatography. The deaminated metabolites 3,4-dihydroxy phenyl glycol (DOPEG) and 3,4-dihydroxy mandelic acid (DOMA) constituted ...
Chan L - - 1994
In the isolated perfused rat kidney, endothelin (ET) added to the perfusate at concentrations ranging from 50 to 500 pmol/l resulted in a dose-dependent reduction in renal perfusate flow (RPF) and inulin clearance (CIn). The decrease in RPF (17 +/- 3 vs. 34 +/- 3 ml.min-1 x g-1; P < ...
Senoh M - - 1993
OBJECTIVE: The study was designed to demonstrate the time course of neutrophil chemotactic factor (NCF) release from blood-free isolated rat hearts and to clarify the characteristics of NCF in order to facilitate its identification. METHODS: Coronary effluents were collected every minute from Langendorff perfused rat hearts during ligation of the ...
Lukas A - - 1993
BACKGROUND: Acute ischemia is known to produce more severe electrophysiological disturbances in canine ventricular epicardium than endocardium, although the mechanism for the differential sensitivity is still unresolved. Recent studies have demonstrated the presence of a prominent transient outward current (Ito) in ventricular epicardium but not endocardium. The present study was ...
Williams K A - - 1993
The frequency of "clandestine" (electrically silent and asymptomatic, but scintigraphically evident) myocardial ischemia during treadmill and upright leg cycle ergometric studies was compared in 38 patients with coronary artery disease and reversible ischemia on both thallium-201 scintigraphy and exercise radionuclide angiography. A similar peak double product was attained in both ...
Latini S - - 1993
The effect of idebenone on the changes in adenosine and nucleotide metabolism occurring in hippocampal slices after ischemia-like conditions (superfusion with glucose-free Krebs solution gassed with 95% N2-5% CO2) and during reperfusion with normal Krebs solution was investigated by measuring adenosine and inosine outflow, and adenosine and adenine nucleotide levels ...
Barbour M M - - 1993
OBJECTIVES: The effects of varying concentrations of theophylline on exercise-induced myocardial ischemia were evaluated in patients with stable coronary artery disease. BACKGROUND: Theophylline is a competitive antagonist of adenosine and may have potential as an anti-ischemic medication. It is not known whether these effects on myocardial ischemia are concentration dependent. ...
Montgomery J A - - 1993
Aldehydes represent an important class of cytotoxic products derived from free radical-induced lipid peroxidation which may contribute to reperfusion injury following myocardial infarct. Metabolism of aldehydes in the heart has not been well characterized aside from conjugation of unsaturated aldehydes with glutathione. However, aliphatic aldehydes like hexanal do not form ...
Fujita S - - 1993
Need of oxygen by the liver during hypothermic perfusion was evaluated using isolated perfusion model. Livers were perfused by a continuous perfusion system with oxygen saturated perfusate or nitrogen saturated perfusate, or simply stored for 12 hours at 5 degrees C. Quality of individual liver was assessed at one hour ...
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