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51.
We present a very rare case of gigantic hydrocalycosis which was caused by an obstructed stone. It was so large that it displaced the rest kidney into the contralateral lumbar fossa giving the appearance of a crossed ectopic kidney.  相似文献   
52.
Changes in carbohydrate metabolism were studied in midgut gland, muscle, and gill tissues of marine prawn Penaeus indicus exposed to a sublethal concentration (0.3 ppm) of phosphamidon. A significant decrease in glycogen and pyruvate and an increase in lactate content were observed in all phosphamidon-exposed prawn tissues after 96 hr. An increase in phosphorylase a and aldolase activity levels suggested the increased formation of triose sugars during phosphamidon toxicity. LDH activity was considerably decreased and an increment in lactate content was observed which indicates reduced mobilization of pyruvate into the citric acid cycle. Glucose-6-phosphate dehydrogenase activity was considerably increased, suggesting the enhanced oxidation of glucose in the hexose monophosphate shunt pathway. Krebs cycle enzymes such as NAD-isocitrate dehydrogenase, succinate dehydrogenase, and malate dehydrogenase were found to be decreased, suggesting the impairment in mitochondrial oxidative metabolism due to the acute toxic impact of phosphamidon. Cytochrome-c oxidase and Mg2+ ATPase activity levels were also decreased considerably, suggesting impaired energy synthesis and breakdown during phosphamidon toxicity, as a result of reduced oxidation of glucose aerobically. The increase in acid and alkaline phosphatase activities indicates the enhanced breakdown of phosphate to release energy in view of inhibiton or impairment in the ATPase system during phosphamidon-induced stress. These results suggest that phosphamidon has a profound effect on the oxidative metabolism of prawn which results in the triggering of compensatory metabolic pathways for survivability.  相似文献   
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54.
研究氟烷吸入麻醉在中枢神经系统作用部位。应用c-fos基因免疫组织化学方法。SD大鼠在吸入氟烷浓度为0.75%.1。5%和2%麻醉1h后,Fos阳性神经元主要分布于端脑;梨状皮层,杏仁核簇,伏核,外侧隔核,终纹麻核、海马CAI区,海马回嗅觉小岛;  相似文献   
55.
The ability to identify, isolate, and transplant progenitor cells from solid tissues would greatly facilitate the treatment of diseases currently requiring whole organ transplantation. In this study, cell fractions enriched in candidate epithelial progenitor cells from the rat pancreas were isolated and transplanted into the liver of an inbred strain of Fischer rats. Using a dipeptidyl dipeptidase IV genetic marker system to follow the fate of transplanted cells in conjunction with albumin gene expression, we provide conclusive evidence that, after transplantation to the liver, epithelial progenitor cells from the pancreas differentiate into hepatocytes, express liver-specific proteins, and become fully integrated into the liver parenchymal structure. These studies demonstrate the presence of multipotent progenitor cells in the adult pancreas and establish a role for the liver microenvironment in the terminal differentiation of epithelial cells of foregut origin. They further suggest that such progenitor cells might be useful in studies of organ repopulation following acute or chronic liver injury.  相似文献   
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Between 1954 and 1986 inclusive, 160 children in the North West Region of England were registered with histologically proven lowgrade astrocytomas (grade 1 or 2). Ten died before receiving any treatment, and a further seven died within 28 days of surgery, leaving 143 children whose survival in relation to treatment modality is the subject of this paper. Low-grade astrocytomas are responsive to radiation therapy. This treatment has no clear benefit to offer children with superficial tumours that can be resected completely or nearly so, but significantly improves survival rates when tumours are deep-seated and not amenable to excision.  相似文献   
58.
Castleman disease in an 11-year-old girl appeared as a neck mass that grew despite antibiotic treatment. MR showed a well-defined solid mass, isointense with muscle on short-repetition-time/short-echo-time images, with a stellate area of central hypointensity on long-repetition-time/long-echo-time images, that did not enhance with gadolinium.  相似文献   
59.
Laparoscopic appendicectomy has been the subject of several encouraging reports, but has not as yet gained widespread acceptance. We present a series of 159 consecutive laparoscopic appendicectomies performed, over a 4 yr period, in both adults and children. We find the procedure as safe as its open counterpart, with patients fit to leave hospital within the same time period. Perforated appendices were amenable to this procedure, and the location of the appendix did not alter the outcome. Children responded as well as adults post-operatively. Obesity may be an indication for this form of treatment. Removal of displaced faecoliths associated with perforated appendicitis is a difficult technical problem in less than 5 per cent of patients.  相似文献   
60.
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