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S Cuzzocrea B Zingarelli D Villari AP Caputi G Longo 《Canadian Metallurgical Quarterly》1998,63(2):PL25-PL30
During inflammation nitric oxide reacts at near diffusion limited rates with superoxide to form the strong oxidant peroxynitrite. Nitration on the ortho position is a major product of peroxynitrite attack on proteins. In the present study we investigated whether immunohistochemical detection of nitrotyrosine (footprint of peroxynitrite) can be associated with human hepatitis. Paraffin-embedded liver tissue biopsies from patients with chronic active hepatitis, chronic active hepatitis plus cirrhosis and chronic persistent hepatitis exhibit significant specific immunostaining with the antibody to nitrotyrosine. Positive staining was found in 57% and 72% of tissue specimens from patients with chronic hepatitis and cirrhosis, respectively. Immunohistochemical staining of nitrotyrosine residues was found in the hepatocytes and Kuppffer cells of the necrotic area. The presence of nitrotyrosine indicates that oxidants derived from nitric oxide such as peroxynitrite are generated in human hepatitis and may be involved in its pathogenesis. 相似文献
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This study was undertaken to compare the fixation of the semitubular blade plate with that of the AO T plate. Cadaveric humeri (n=12 pairs) from an elderly population (41 to 89 years) had either a blade plate (n=12) or a T plate (n=12) fixed to them, subsequent to which a transverse osteotomy was performed. Mechanical testing in tension was performed in 1 series (n=5, blade plate; n=5, T plate) by applying a single maximal load to failure and in a second series (n=7, blade plate; n=7, T plate) by applying submaximal cyclic loading before failure was induced. Results showed that the fixation provided by the semitubular blade plate was significantly better (P < .05) than that of the T plate in those specimens subjected to submaximal cyclic loading before failure (series 2). This latter testing method contains some component of the clinical situation compared with monotonic distraction to failure. Based on these results plus favorable clinical results reported in the literature, the semitubular blade plate is possibly a better alternative to the T plate in the management of proximal humeral fractures that require open reduction and internal fixation. 相似文献
126.
The poor nutritional status of Aboriginal Australians is a serious and complex public health concern. We describe an unusually successful health and nutrition project initiated by the people of Minjilang, which was developed, implemented and evaluated with the community. Apparent community dietary intake, assessed by the 'store-turnover' method, and biochemical, anthropometric and haematological indicators of health and nutritional status were measured before intervention and at three-monthly intervals during the intervention year. Following intervention, there was a significant decrease in dietary intake of sugar and saturated fat, an increase in micronutrient density, corresponding improvements in biochemical indices (for example, a 12 per cent decrease in mean serum cholesterol, increases in serum and red cell folate, serum vitamin B6 and plasma ascorbic acid), decrease in mean systolic and diastolic blood pressures, a normalisation of body mass index, and a normalisation of haematologic indices. The success of this project demonstrates that Aboriginal communities can bring about improvements in their generally poor nutritional status, and that the store-turnover method provides a valid, inexpensive and noninvasive method for evaluating the resultant changes in community diet. Although the project was undoubtedly effective in the short term, further work is in progress to assess individual strategies with respect to sustainability, cost-effectiveness and generalisability. 相似文献
127.
Three cases of upper limb deep venous thrombosis occurring in association with assisted conception treatment are presented. The accepted argument that lower limb thrombosis occurring in cases of complicated or severe hyperstimulation syndrome represents the likeliest thrombo-embolic disorder in this situation is questioned. 相似文献
128.
L Pasamontes M Haiker M Wyss M Tessier AP van Loon 《Canadian Metallurgical Quarterly》1997,63(5):1696-1700
The finding of heat-stable enzymes or the engineering of moderately thermostable enzymes into more stable ones by random or site-directed mutagenesis has become a main priority of modern biotechnology. We report here for the first time a heat-stable phytase able to withstand temperatures up to 100 degrees C over a period of 20 min, with a loss of only 10% of the initial enzymatic activity. The gene (phyA) encoding this heat-stable enzyme has been cloned from Aspergillus fumigatus and overexpressed in Aspergillus niger. The enzyme showed high activity with 4-nitrophenyl phosphate at a pH range of 3 to 5 and with phytic acid at a pH range of 2.5 to 7.5. 相似文献
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