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991.
992.
The present investigation shows the effect of combined dietary deprivation of fat and vitamin A on N-nitrosodiethylamine (NDEA) induced lung carcinogenesis in male Swiss NMRI mice. Lung tumors were induced by three intragastric administrations of NDEA (80, 80, 40, mg/kg body wt.) in normal saline with a gap of 4 weeks between each administration. The tumor incidence and tumor burden in control animals were found to be 39.1 and 3.9%, respectively. Fat deficiency decreased the tumor incidence to 30.4% and tumor burden to 3.7%. On the other hand, vitamin A deficiency increased them to 95.6 and 6.8%, respectively. Fat deprivation in the diet of animals fed with vitamin A deficient diet decreased the tumor burden and tumor incidence to 59.0 and 4.0%, respectively which were still more than in the control animals. This study suggests a protective role for low intake of fat in vitamin A deficiency.  相似文献   
993.
Peritoneal sclerosis, a disorder similar to that previously identified in nonuremic patients, is being noted in peritoneal dialysis patients with increasing frequency. The etiology in dialysis patients remains unknown. An association with previous or ongoing peritoneal inflammation or irritation suggests that the incidence of peritoneal sclerosis could be reduced by rapidly controlling peritonitis and by eliminating the irritant properties of catheters, dialysate, and other materials used in performing peritoneal dialysis. If peritoneal sclerosis does supervene, weight loss, abdominal pain, and intestinal obstruction may occur and further peritoneal dialysis may become impossible because of abdominal pain or poor fluid and solute transfer.  相似文献   
994.
Patients presenting with acute disseminated intravascular coagulation (DIC) as the first symptom of malignancy are rare. A 68-year-old man presented with DIC. On evaluation, he was found to have adenocarcinoma of the stomach. Resection of the growth controlled the DIC for a few days, after which the patient developed altered coagulation parameters and sepsis, and succumbed.  相似文献   
995.
Five severe reactions occurred in four maintenance hemodialysis patients 1 to 5 minutes after initiating dialysis with Cuprophan capillary dialyzers. All reactions were life-threatening and one resulted in death. Inadequate rinsing of the dialyzers was probably the cause of the reactions. The severe reactions were managed by immediate discontinuation of dialysis and the institution of supportive treatment. Antianaphylactic measures were also attempted, but their therapeutic effectiveness remains to be determined.  相似文献   
996.
A young boy presented with mental retardation and seizures with extensive hairy naevi. After a fluctuating clinical course over the next 2 years, he worsened rapidly with signs of rising intracranial pressure. A CT scan revealed unsuspected features of Dandy-Walker syndrome. The clinical course is traced till the patient's death, and the implications of the coexistence of these rare conditions are discussed in view of the proposed hypotheses regarding the pathogenesis of Dandy-Walker syndrome.  相似文献   
997.
Background: Isoflurane enhances mechanical function in hearts subject to normothermic global or regional ischemia. The authors examined the effectiveness of isoflurane in preserving mechanical function in hearts subjected to cardioplegic arrest and prolonged hypothermic no-flow storage. The role of isoflurane in altering myocardial glucose metabolism during storage and reperfusion during these conditions and the contribution of adenosine triphosphate-sensitive potassium (KATP) channel activation in mediating the functional and metabolic effects of isoflurane preconditioning was determined.

Methods: Isolated working rat hearts were subjected to cardioplegic arrest with St. Thomas' II solution, hypothermic no-flow storage for 8 h, and subsequent aerobic reperfusion. The consequences of isoflurane treatment were assessed during the following conditions: (1) isoflurane exposure before and during storage; (2) brief isoflurane exposure during early nonworking poststorage reperfusion; and (3) isoflurane preconditioning before storage. The selective mitochondrial and sarcolemmal KATP channel antagonists, 5-hydroxydecanoate and HMR 1098, respectively, were used to assess the role of KATP channel activation on glycogen consumption during storage in isoflurane-preconditioned hearts.

Results: Isoflurane enhanced recovery of mechanical function if present before and during storage. Isoflurane preconditioning was also protective. Isoflurane reduced glycogen consumption during storage under the aforementioned circumstances. Storage of isoflurane-preconditioned hearts in the presence of 5-hydroxydecanoate prevented the reduction in glycogen consumption during storage and abolished the beneficial effect of isoflurane preconditioning on recovery of mechanical function.  相似文献   

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