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41.
Experimental small bowel transplantation has continued to be a complex procedure with high mortality. We investigated the technical aspects of small bowel transplantation in an effort to define a procedure that would result in an improved survival rate. Three methods of graft harvesting were examined in a model of canine small bowel autotransplantation. Harvesting the graft by first flushing with room-temperature lactated Ringer's followed by iced lactated Ringer's resulted in the best preservation and subsequently the best survival rate (71%). Flushing with iced lactated Ringer's alone resulted in survival rates of 22 and 50% in two additional groups. We also investigated two methods of graft reanastomosis. Although either venous drainage regimen appears to be suitable, graft venous reanastomosis to the host portal vein resulted in a slightly higher postoperative weight than reanastomosis to the host inferior vena cava. A model of small bowel transplantation with a high long-term survival rate has been developed. This model can now be applied to studies of the various physiological aspects of small bowel transplantation.  相似文献   
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Hepatocyte contribution to hepatic collagen production in vivo was estimated in rats, based on the fact that ornithine is used for protein synthesis in the liver as arginine after conversion by way of the urea cycle only by hepatocytes. From rats given a mixture of [14C] ornithine and [3H]arginine, hepatic collagen and serum albumin were obtained. The hepatocyte contribution was calculated from the 14C and 3H in arginine purified from collagen and albumin by high performance liquid chromatography. The contribution was less than 10% of total collagen production in normal and early fibrotic livers induced by a single dose of carbon tetrachloride or dimethylnitrosamine. We conclude that hepatocytes may play a minor role in collagen production in normal and early fibrotic rat livers.  相似文献   
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A 54 year-old female who had a history of hemoptysis was admitted to our hospital because of dyspnea on effort. Pulmonary arterial pressure was elevated and pulmonary arteriography showed multiple pulmonary arterial aneurysms and occlusion of the left upper lobe pulmonary artery. Systolic pulmonary arterial pressure was 110 mmHg when measured by continuous wave Doppler echocardiography. From the clinical and angiographical findings, we diagnosed this patient as having Hughes-Stovin's syndrome (forme fruste). 30 mg of diltiazem per day was initially used, and 80 mg was used thereafter. After 2 months follow up of the medication with diltiazem, systolic pulmonary arterial pressure decreased from 110 mmHg to 61 mmHg and clinical symptoms improved dramatically.  相似文献   
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Frequent loss of heterozygosity at chromosomal loci in a specific tumor type may indicate the presence of a tumor suppressor gene. We have examined loss of heterozygosity on chromosome 8p in paired tumor and constitutional DNA from 346 patients representing seven different types of human cancer. Frequent allelic losses were observed in hepatocellular carcinoma (22 of 46 cases, 47.8%), in colorectal cancer (12 of 26, 46.2%), and in non-small cell lung cancer (14 of 35, 40.0%), in contrast to low frequencies detected in breast cancer (5 of 56, 8.9%) and renal cell carcinoma (2 of 27, 7.4%). Ovarian cancer and gastric cancer showed intermediate frequencies of 33.3% and 22.2%. Subsequent analysis of 120 hepatocellular carcinomas and 94 colorectal cancers with five polymorphic markers along the short arm of chromosome 8 defined commonly deleted regions within the same chromosomal interval, 8p23. 1-8p21.3, suggesting that one or more tumor suppressor genes for both cancers may be present in that region.  相似文献   
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Achieving coverage after digital injury is crucial, because simple skin defects can expose essential structures such as tendons or bones. This is particularly true on the dorsal surfaces of the digits, where the skin provides the only protection for the tendons. However, longitudinal skin defects of the digit have not been specifically identified in the literature and there have been few reports focusing on longitudinal dorsal skin defects. Here we report on the use of a bipedicle flap for reconstruction of complex longitudinal dorsal tissue defects of the digits, including those associated with tendon or bone damage.  相似文献   
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Supraventricular tachyarrhythmia (SVT) such as sinus tachycardia and atrial dysrhythmia is a life-threatening problem in the period immediately following an open-heart operation. Because of their negative inotropic effects, antiarrhythmic agents are not recommended for patients with low cardiac output syndrome. A device was developed that topically cools the right atrial surface for antiarrhythmic treatment. In experiments, this device lowered right atrial temperature and did not affect the temperature of the right ventricle or the whole body. When right atrial temperature decreased from 37 degrees to 28 degrees C, heart rate was reduced from 146.3 to 109.7 beats per minute (p less than .001). Meanwhile, cardiac output and blood pressure remained within control levels. In the treatment of experimental SVT induced by the intravenous infusion of isoproterenol hydrochloride and by direct application of aconitine, this method worked effectively and was reproducible. The results demonstrated the beneficial effects of this method in the treatment of SVT in experimental studies and suggested its future clinical application following open-heart operations.  相似文献   
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