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991.
992.
993.
This paper describes a quick procedure for cadaveric liver graft retrieval during multiple organ harvesting. The technique is based on minimal preliminary dissection, absence of in situ direct portal perfusion, and en bloc removal of the liver and pancreas, with an aortic patch encompassing the coeliac trunk and superior mesenteric artery. The results of 110 pediatric liver transplantations with 109 organs harvested using this technique are reported. There were no graft harvesting injuries. The liver graft primary nonfunction rate was 4.5% (5/110). The 3-month retransplantation rate was 10%. The actual patient survival rates were 93% at 3 months and 90% at 1 year; actual graft survival rates were 85.5% and 78%, respectively. The technique described was at least as safe as conventional procedures. A major advantage of the procedure is its flexibility, which allows for the easily combined procurement of other organs (whole pancreas and intestine).  相似文献   
994.
BACKGROUND: Erythrocytosis is a common complication of renal transplantationwith an incidence of up to 17%. It is associated with an increasedrisk of complications due to thromboembolic events and has traditionallybeen treated by intermittent venesection. More recently, angiotensin-convertingenzyme inhibitors have been shown to cause a fall in haematocritin a number of groups of subjects and some uncontrolled studieshave shown these drugs to be of possible therapeutic benefitin post renal transplant erythrocytosis. METHODS: We performed a randomized double-blind placebo-controlled studyin 25 patients with post-transplant erythrocytosis. Subjectsreceived either 2.5 mg of enalapril daily or a placebo for 4months and all patients completed the study period without anyserious adverse effects. RESULTS: Haematocrit fell from 52.7 (±SEM 0.7) to 47.1 (±1.8) at 1 month and 46.1 (± 1.2) after 4 months in patientsreceiving enalapril, with no change in the placebo group (P=0.004).We did not demonstrate any change in serum erythropoietin ineither group. CONCLUSION: Angiotensin-converting enzyme inhibitors are a safe and effectiveform of treatment for erythrocytosis developing after renaltransplantation. The mechanism of action, however, is not mediatedby changes in erythropoietin production and remains uncertain.  相似文献   
995.
The production and prevention of calcium paradox injury in myocardium was studied in a canine model of cardiopulmonary bypass with multidose, moderately hypothermic, crystalloid cardioplegic solution. During 4 1/2 hours of global ischemia, three groups of six dogs each received one of three histidine-buffered cardioplegic solutions (500 ml initially and 250 ml every 30 minutes) at 27 degrees C. Group 1 cardioplegic solution was calcium free, group 2 solution contained a trace amount of calcium chloride (70 mumols /L), and group 3 cardioplegic solution was calcium free but contained diltiazem (150 micrograms/kg body weight). Left ventricular function measured as percent control of developed pressure revealed significantly greater (p less than 0.05) recovery in groups 2 and 3. Triphenyltetrazolium chloride staining showed 35% +/- 9% (mean +/- standard error) of heart mass necrosis in group 1 versus 0% and 0.5% +/- 0.4% in groups 2 and 3, respectively (p less than 0.001). Electron microscopy revealed ultrastructural changes characteristic of calcium paradox injury in group 1 myocardium. Calcium paradox injury was produced in an in vivo model of global myocardial ischemia and multidose cardioplegia despite moderate hypothermia and non-coronary collateral flow. The addition of either trace levels of calcium or diltiazem to the cardioplegic solution was effective in preventing this injury.  相似文献   
996.
Between 4/1986 to 1/1989, 74 orthotopic liver transplantation were performed in 62 patients (62 first liver transplants, 10 as second graft and two as a third graft); 57 in adults and 17 in children. The main indication for the operation was liver cirrhosis (61.4%) (the most frequent etiology was alcoholic cirrhosis, 28.5%). Six cirrhotic patients had a hepatocarcinoma (9.6%). Two received a liver and kidney transplant due to terminal renal insufficiency and hemodialysis. The most frequent indication in children was biliary atresia (33.3%). Six patients had a fulminal liver failure (9.6%). AB0 blood group compatibility was identical in 87.5%, compatible in six and incompatible in three patients. Total orthotopic liver transplantation was performed in 67 patients, and size-reduced liver was indicated in 7 patients. Extracorporeal veno-venous bypass was used in adults but never in children. In 93.1% of the transplants a single hepatic artery was anastomosed to the recipient and in 6.9% a double anastomosis was performed. In 62.5% of the patients a end-to-end choledocho-choledochostomy was performed and in 34.8% hepatico-jejunostomy was indicated. Three months postoperative mortality rate was 12.9%. Arterial stenosis and thrombosis were the most frequent complication.  相似文献   
997.
A spinal cord injury model is described using chymopapain as a neurotoxic agent in rats. The trauma was evaluated by neurophysiological and morphological methods. Electrically evoked compound action potentials were used to quantify the neurophysiological effects caused by the injection of chymopapain into the lumbar dural theca in rats. A branch of the sciatic nerve was stimulated with voltage impulses of constant amplitude (40 V) and duration (0.1 ms) at the right external malleolus. The responses were recorded at the dorsal root entry zone L1. We used different doses of the enzyme (1000 i.u./ml; 2500 i.u./ml; 5000 i.u./ml). A total amount of 0.1 ml was injected into the rats' lumbar spinal canal intrathecally (n = 18). The control rate (n = 8) were subjected to exactly the same stimulus and recording procedures but the test solution was a corresponding volume of isotonic saline. Two hours after injection the animals were examined clinically and then sacrificed for histology. The prolongation of the latency of the electrically evoked potentials caused by the enzyme was very clear at the doses of 2500 i.u. and 5000 i.u. being about 10-15% relative to the mean latency before administration of the drug. The histological evaluation showed hemorrhage, vascular damage and indirect signs of myelin edema of the lumbar nerve tissue. Our study indicates that chymopapain injections into the lumbar spinal canal can be used as a reproducible model for spinal cord injury research.  相似文献   
998.
12 giant intracranial aneurysms were studied by MRI. Intraluminal thrombosis was observed in 9 aneurysms. Thrombosis was found more frequently in larger aneurysms. Thrombi were formed posteriorly or inferiorly in the lumen of 4 among 5 IC-cavernous aneurysms. Location of the neck of the aneurysms and stagnation of blood flow influenced by gravity may be causative factors determining the location of thrombi. In 6 aneurysms intraluminal thrombi were inhomogeneous on MRI, suggesting that the thrombi had been formed at different times. New thrombi were formed between the aneurysmal wall and the old thrombus in 3 cases. Dissection of the aneurysmal wall by residual blood flow in the lumen or hemorrhage in the aneurysmal wall may be one of the growth mechanisms of giant intracranial aneurysms.  相似文献   
999.
The hepatic circulation of patients with hilar carcinoma and icterus was studied by isotope technique. A marked alternation in blood flow was observed, that is that the ratio of the circulation of the hepatic artery and the portal vein became balanced. By elimination of the icterus, the hepatic circulation normalized. This allowed the conclusion that the change in blood flow must have rather been due to the mechanical icterus and the increased pressure of the bile duct than to the tumorous infiltration and therefore the earliest possible elimination of the icterus is urgently indicated.  相似文献   
1000.
The pathomorphological and clinical findings were investigated in 10 cases of drug-induced hypersensitivity nephritis. Hypersensitivity due to drugs was strongly suggested by the lymphocyte stimulation test in all patients. The offending drugs included penicillin, cephem derivatives, nonsteroidal anti-inflammatory drugs, and minocycline. All patients developed acute renal failure shortly after administration of regular doses of the drugs. Allergic symptoms plus a raised level of serum IgE or eosinophilia were seen in 7 patients. The remaining 3 patients receiving nonsteroidal anti-inflammatory drugs had no allergic symptoms, but developed severe proteinuria. Eight patients without severe glomerular damage recovered after withdrawal of the offending drugs and temporal dialysis and/or steroid therapy. Renal biopsies revealed tubulitis and tubular epithelial degeneration with interstitial edema as the common characteristic findings. Granulomatous lesions were occasionally observed. Multinucleated giant cells found in the granulomas were positive for LN-3 which is compatible with HLA-DR antigen. The glomeruli appeared normal, except in 2 cases in whom crescentic glomerulonephritis and thrombotic microangiopathy were seen. Our study suggests that the lymphocyte stimulation test and renal biopsy are the most useful means to confirm the diagnosis and provides further evidence for the participation of cell-mediated immunity in the pathogenesis of drug-induced hypersensitivity nephritis.  相似文献   
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