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Immunopathology of glomerulonephritis associated with chronic woodchuck hepatitis virus infection in woodchucks (Marmota monax).
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D. N. Peters H. Steinberg W. I. Anderson W. E. Hornbuckle P. J. Cote J. L. Gerin R. M. Lewis B. C. Tennant 《The American journal of pathology》1992,141(1):143-152
Retrospective analysis of necropsy findings of 705 woodchucks was performed to determine the prevalence and morphology of immune-mediated glomerulonephritis, its relationship to woodchuck hepatitis virus (WHV) infection, and the presence of major WHV antigens. Twenty-six woodchucks had glomerular lesions. Renal tissue of the 26 animals was evaluated histologically and immunohistochemically for immune-mediated glomerulonephritis. Of these 26 animals, immune-mediated glomerulonephritis was diagnosed in six, all of which were chronic WHV carriers. Membranous glomerulonephritis was identified in three animals, two of which also had mesangial proliferation. Host immunoglobulin was present within the mesangium and along capillary loops in all three. Woodchuck hepatitis virus core antigen (WHcAg) was present along capillary loops of two of these animals, one membranous and one mixed, and in the mesangium of all three. Woodchuck hepatitis virus surface antigen (WHsAg) deposition was similar to WHcAg deposition but was only present along capillaries in those animals with mixed nephritis. The remaining three animals had mesangial proliferation. WHsAg and host immunoglobulin deposition were predominately mesangial; WHcAg was not detected. Transmission electron microscopy showed thickening of the capillary loop basement membranes and subepithelial electron-dense deposits in animal one, and deposits in the mesangium in animal six. 相似文献
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The pH and acid content of 63 glucose-based solutions was measured up to eight years after their expiry. The pH ranged from 2.27 to 4.33. Newly manufactured solutions with 5 per cent or less of glucose which were packaged in plastic bags contained in the order of 0.01 mEq/L of acid per gram of glucose. Solutions with higher glucose concentrations had lower pH and greater acid. As solutions in bags became older, pH decreased and acid increased. In contrast, 25 per cent and 50 per cent glucose solutions in glass containers were much less acid and showed only slight changes with age in pH or acid. The greater rate of acid increase in glucose solutions in plastic bags may be due to the bags being permeable to oxygen and thus allowing slow oxidation of the glucose. 相似文献
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Community surveys are increasingly being used as a method of collecting health and lifestyle data. This report describes the use of a simple question on hearing difficulties within such a survey. A systematic sample of 2.5% of the electoral register of the four Parliamentary constituencies of Cardiff, Wales, was drawn. Of the 5145 individuals in the sample, 83% responded. Age and social class explained much of the variability in reported hearing difficulties. A recent fall and cigarette consumption were associated with hearing problems, but the contribution of alcohol consumption while potentially important did not reach statistical significance. This self-administered community survey provided hearing data which are consistent with other specialized studies and is a viable route for the assessment of community needs. 相似文献
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M T Ott L Ott D Haack T A Colacchio J Lewis 《Archives of surgery (Chicago, Ill. : 1960)》1992,127(9):1089-1093
Thirteen morbidly obese individuals were studied prospectively for 1 year after vertical banded gastroplasty (VBG) to determine the relationships between energy balance equation parameters and excess weight loss. The measured energy expenditure (MEE), as determined by indirect calorimetry, was not correlated with weight loss. However, when this parameter was expressed as a ratio to the predicted energy expenditure (PEE), the ratio was significantly correlated with the postoperative excess weight loss at 2, 6, and 12 months. The mean daily energy intake after the VBG was 2715 +/- 865 kJ. The postoperative energy intake was not correlated with the excess weight loss. Diet-induced thermogenesis was studied in eight patients. The mean diet-induced thermogenesis was 10.31% +/- 13.92%. The diet-induced thermogenesis was not correlated with the postoperative excess weight loss. The preliminary findings of this trial suggest that the MEE/PEE ratio is useful in predicting excess weight loss after VBG. 相似文献
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Two experiments were conducted to assess the effects of chronic subcutaneous injections of morphine (1.0 mg/kg) or saline on the pattern and amount of sweetened ethanol and water intake in fluid restricted Long-Evans rats. Following daily injections, 2-h two-bottle choice tests were conducted with water and an ethanol solution (15% ethanol v/v in 5% sucrose w/v). During a 20-day acquisition phase (Experiment 1), ethanol intake patterns and amounts did not differ between saline (n = 6) and morphine (n = 6) groups. Both groups exhibited ethanol intake patterns that decreased exponentially throughout the session suggesting control by fluid restriction procedures. Morphine decreased water intake during initial periods of each session and increased intake during later periods. In Experiment 2, morphine and saline injections were reversed across three phases with the same rats. Morphine increased total ethanol consumption during the first few days of each 15-day phase, but the groups did not differ thereafter, and the initial increases produced no statistically significant group differences. Additionally, morphine augmented ethanol intake in early portions of sessions, while water intake was decreased and increased during early and later portions of each session, respectively. Analysis of the data from the last 5 days of each phase indicated that, when injected with morphine, the group which received saline during acquisition consumed significantly more ethanol solution than the group injected with morphine during acquisition. The effect on patterns of water and ethanol intake were observed, regardless of the drug injected during acquisition.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献