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101.
JV López-Mut M Cubells S Campos V Miranda P Rivera 《Canadian Metallurgical Quarterly》1998,23(6):558-559
Jejunogastric intussusception is a rare complication of gastric surgery. We report a case in a 41-year-old woman subjected to gastrojejunostomy with truncal vagotomy 3 years before for pyloric stenosis. The jejunogastric intussusception was diagnosed by upper gastrointestinal series, ultrasonography, and computed tomography. Surgical management consisted of reduction and fixation. Treatment should be as early as possible to prevent gangrene of the invaginated segment. 相似文献
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In the course of biotransformation reactions catalyzed both by cytochrome P450 and by conjugating enzymes, drug-derived reactive metabolites and active oxygen species can appear that may escape the detoxification process, initiating radical chain reactions (e.g., lipid peroxidation), covalently binding to macromolecules (proteins, DNA), or impairing the energetic balance of cells. This is usually followed by alterations of ion homeostasis that precede irreversible biochemical changes and cell death. There are, however, cellular mechanisms of defense that prevent, or repair, the damage caused by these reactive intermediates. Ultimately it is the balance between bioactivation, detoxification, and defense mechanisms that determines whether a compound will or will not elicit a toxic effect. Cultures of hepatocytes, including those of human origin, can be used to elucidate the mechanisms of drug toxicity. This is illustrated in the study of the mechanism of hepatotoxicity by diclofenac. Much less cytotoxicity is observed in nonmetabolizing hepatomas than in hepatocytes. The observed cell dysfunction parallels the biotransformation of the drug, and particularly the formation of the minor metabolite N,5-dihydroxydiclofenac by hepatocytes. This compound is able to inhibit mitochondrial ATP synthesis in hepatocytes. 相似文献
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A survey of laboratory records was made to assess the value of the precipitin test and isolation methods in the diagnosis of farmer's lung disease and also to determine its prevalence in the farming population of Somerset. A link was established between the clinical diagnosis as written on the form that accompanied the specimen and the actual number of positive laboratory diagnoses made. Fifty (43%) of the clinically diagnosed patients were serologically positive for farmer's lung during a four-year period. If the clinically diagnosed but serologically negative cases of farmer's lung disease are added to this number, a prevalence of about 23 per 1000 of the farming population of Somerset is obtained. 相似文献
108.
Effect of contact lens wear on the conjunctival mucous system 总被引:1,自引:0,他引:1
Biopsy specimens from the upper tarsal conjunctiva of 20 contact lens wearers with a clinically evident increase in mucus and ten non-lens wearing subjects were examined by light microscopy and scanning and transmission electron microscopy to determine the effect of contact lens wear on the mucous cell system(s). Three types of crypts associated with mucous secretion were found in all specimens: those with intracellular openings (type I, 0.1 to 0.2 mum) associated with non-goblet mucous secretory cells; those with small intercellular openings (type II, 1 to 2 mum) usually associated with goblet cells, and those with intraepithelial and intrastromal crypts with large intercellular openings (type III, 10 to 60 mum) lined with goblet and non-goblet mucous secretory cells. Contact lens wearers had increased numbers of non-goblet cells with mucous secretory vesicles lining the surface of the conjunctiva and the epithelial infoldings of type III crypts than did the normal subjects. We conclude that increased mucous secretion in contact lens wearers is associated with an increased number of cells and number of secretory vesicles involved in the non-goblet cell mucous system. 相似文献
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