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101.
Using Wistar stain male rats, it has been shown that 2 atmospheric pressures associated with oxygen saturation, together or singly for 90 minutes daily for successive 46 days, resulted in no significant change on the ratio of testes to body weight. No significant change was observed in the incorporation of 3H-thymidine into testes and pituitary glands between the pressure-treated groups and the control group.  相似文献   
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A surgical approach to the clivus and anterior spine from C-1 to the upper part of C-5 is described. It is a direct approach that provides a wider and longer exposure than does the transoral approach. Despite the seemingly radical incision, the cosmetic deformity and functional loss are minimal. This approach is useful for the surgical treatment of a variety of processes that are situated ventral to the upper cervical spinal cord and the cervicomedullary junction.  相似文献   
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PURPOSE: To estimate the impact of visual impairment in older Australians on the use of community support services. METHODS: In the Blue Mountains Eye Study, 3654 people aged 49 or older were examined- 82.4% of eligible residents in an area west of Sydney, Australia. Presenting and best-corrected visual acuities were measured using a LogMAR chart. Subjects were categorized as having visual impairment if their better eye read 40 or fewer letters (20/40 or worse). Interview data included marital and other socioeconomic status measures, living status (alone or with spouse or other person), use of community support services, reliance on regular help from nonspouse family members or friends, and perceived ability to go out alone. RESULTS: After adjusting for age, gender, education, living status, walking disability, and health-related factors, for each one-line (five-letter) decrease in best-corrected visual acuity, there was a corresponding increase in reliance on community support services (odds ratio [OR], 1.17; 95% confidence interval, [CI] 1.07-1.28) or combined community and family support (OR 1.22; 95% CI, 1.12-1.32). Visually impaired persons were three times as likely to use regular support services provided by the municipality (OR 3.1; 95% CI, 1.8-5.1). A similar increased reliance on regular help from community, nonspouse family members, or friends was found. Visually impaired persons were also much more likely to state that they thought they were unable to go out alone (OR 6.2; 95% CI, 2.6-14.3). The findings were similar when presenting visual acuity was used to define visual impairment or after subjects with walking disabilities were excluded. Visual impairment seemed to have a greater effect on use of community support services in women than in men. CONCLUSIONS: After adjustment was made for confounding factors, visual impairment was found to affect significantly and negatively the independence of elderly people, particularly older women. Presenting visual acuity closely approximated best-corrected visual acuity in its impact on the use of community support services.  相似文献   
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Oral submucous fibrosis (OSF), a chronic oral mucosal condition commonly found in south Asians, is a disorder characterized by a quantitative as well as a qualitative alteration of collagen deposition within the subepithelial layer of the oral mucosa. Since degradation of collagen by fibroblast phagocytosis is an important pathway for physiological remodelling of soft connective tissues, we have investigated phagocytosis of collagen- and fibronectin-coated latex beads by fibroblast cultures with an in vitro model system. Coated fluorescent latex beads were incubated with human oral mucosa fibroblasts and the fluorescence associated with internalized beads was measured by flow cytometry. Cells from normal tissues that had been incubated with beads for 16 h contained a mean of 75% collagen phagocytic cells and 70% fibronectin phagocytic cells; however, about 15% and 10% of phagocytic cells individually contained more than twice the mean number of beads per cell. In contrast, cells from OSF tissues exhibited a 40% reduction of the proportions of collagen phagocytic cells (mean=35%) and a 48% decrease of the proportions of fibronectin phagocytic cells (mean=22%), none of the cells having a high number of beads as compared to normal fibroblasts. OSF lesions appear to contain fibroblasts with marked deficiencies in collagen and fibronectin phagocytosis. To investigate if inhibition of phagocytosis could be demonstrated in vitro, normal fibroblast cultures were incubated with areca nut alkaloids (arecoline, arecaidine). The cultures had a dose-dependent reduction in the proportions of phagocytic cells. On the other hand, corticosteroid used in the treatment of OSF exhibited a dose-dependent enhancement in the proportion of phagocytic cells. Therefore, our hypothesis for OSF, although oversimplified, is that betel nut alkaloids (arecoline, arecaidine) inhibit fibroblast phagocytosis and this provides a mechanism for the development of OSF. The benefit of a local intralesional injection of corticosteroid is also possibly, at least in part, through an enhancement of fibroblast collagen phagocytosis.  相似文献   
110.
One protein, two enzymes   总被引:1,自引:0,他引:1  
Two enzymes, designated, E-2 and E-2', catalyze different oxidation reactions of an aci-reductone intermediate in the methionine salvage pathway. E-2 and E-2', overproduced in Escherichia coli from the same gene, have the same protein component. E-2 and E-2' are separable on an anion exchange column or a hydrophobic column. Their distinct catalytic and chromatographic properties result from binding different metals. The apo-enzyme, obtained after metal is removed from either enzyme, is catalytically inactive. Addition of Ni2+ or Co2+ to the apo-protein yields E-2 activity. E-2' activity is obtained when Fe2+ is added. Production in intact E. coli of E-2 and E-2' depends on the availability of the corresponding metals. These observations suggest that the metal component dictates reaction specificity.  相似文献   
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