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541.
Culture, Medicine, and Psychiatry - The experiences of dementia sufferers have rarely been examined in sociological literature. This article seeks to describe the experiences of one Alzheimer's... 相似文献
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Dialuric Acid, the reduced form of the β-cell toxin alloxan, and the related fava bean derivatives divicine and isouramil, autoxidize rapidly in neutral solution by a radical mechanism. GSH promotes redox cycling of each compound, with concomitant GSH oxidation and H2O2 production. With superoxide dismutase present, there is a lag period in which little oxidation occurs, followed by rapid oxidation. GSH extends this lag and decreases the subsequent rate of oxidation, so that with superoxide dismutase and a sufficient excess of GSH. coupled oxidation of GSH and each pyrimidine is almost completely suppressed. This mechanism may be a means whereby GSH in combination with superoxide dismutase protects against the cytotoxic effects of these reactive pyrimidines. Superoxide dismutase may also protect cells against oxida-tive stress in other situations where GSH acts as a radical scavenger. and we propose that the concerted action of GSH and superoxide dismutase constitutes an important antioxidant defence 相似文献
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The presence of a nuclear matrix network in animal cells has been claimed by many workers in the last decade. The purpose of our study was to see whether a similar structure could be identified in the cells of higher plants. Our work revealed the presence of a fibrillar nonchromatinic network in Allium cepa nuclei. This could be impregnated with AgNO3 in intact cells as well as in isolated matrices at the light microscope level. It was seen to be associated with the chromosomes from early to late prophase and also in telophase. Ultrastructurally a fibrillar network comparable to that reported earlier from animal cells was observed. This network remained associated with metaphase and anaphase chromosomes and could be digested with pepsin. Biochemical estimation of the isolated matrix revealed it to be made up mainly of proteins (more than 90%), traces of DNA (less than 1%) and a small quantity of RNA. SDS PAGE showed three polypeptide bands in the molecular weight range of 55,000–63,000 daltons. 相似文献
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W Romańczuk 《Polski tygodnik lekarski (Warsaw, Poland : 1960)》1989,44(4):89-91
The author discusses a group of 21 children (15 boys and % girls aged between 4 and 16 years) with diagnosed syndrome of the functional megacolon. Possible causes of the chronic constipation which could lead to the functional megacolon have been analysed. The treatment--preceded by the detailed analysis of anamnesis and laboratory tests (rectoscopy and contrast medium enema)--included: enemas washing out the colon, emollient and laxative agents, fiber-rich diet, and instructions on the proper defecation. Excellent therapeutical results seem to result from the detailed explanation of causes of the functional megacolon. It has enabled to avoid surgical treatment which should be carried out in these cases in which long-term conservative treatment failed. 相似文献