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1.
A case-control design has been applied in the evaluation of improved environmental sanitation on diarrhoeal diseases in rural Malawi. The study demonstrates the feasibility of using such an approach to evaluate two levels of water supply and sanitation service quickly and at moderate cost. Sample sizes would need to be increased substantially to evaluate multiple levels of service or to investigate interactions between water supply and sanitation. The results indicate that children living in families who use good quality water supplies and latrines experience 20% less diarrhoea as reported to the health clinics during the warm, rainy season.  相似文献   
2.
A retrospective analysis was conducted to determine the effects of metformin on glycosylated hemoglobin (HbA1c), body weight, and adverse events in an African-American population. Thirty-six patients who were receiving combination therapy with metformin and either a sulfonylurea or insulin were identified from a hospital pharmacy database. Nineteen patients met the criteria for efficacy analysis. The combination of metformin with either a sulfonylurea or insulin resulted in a decrease of the average HbA1c from a baseline of 10.07% to 7.92% (delta = 2.15%). The effect of combination therapy on weight was variable; however, twice as many patients lost weight compared with those who gained weight. Metformin appeared to be well-tolerated, with gastrointestinal symptoms being the most commonly reported adverse events.  相似文献   
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AIMS: To study tissue expression of L-selectin, a leucocyte cell surface molecule that is considered to be involved in adhesion to certain endothelia, particularly in peripheral lymph nodes and during inflammation, and is shed upon leucocyte activation. METHODS: Leucocytes were examined by immunohistochemistry and double immunofluorescence staining in various lymphoid sites and normal and inflamed extralymphoid tissues. RESULTS: L-selectin was present on mantle zone B lymphocytes in different lymphoid sites, including in intestinal lymphoid tissue, but was absent on germinal centre B cells. Splenic white pulp B cells also expressed L-selectin. The proportion of T lymphocytes expressing L-selectin depended on the site under study, being greatest in peripheral lymph nodes (mean 48% of T cells positive), and lower in mucosal lymphoid sites and spleen (9 and 11% positive, respectively). Non-lymphocytic L-selectin staining was observed on follicular dendritic cells in tonsils and on macrophages in thymus. L-selectin positive leucocytes were rare in normal extralymphoid tissues, and relatively few were seen in most inflammatory settings. However, in rejecting renal transplants, a higher proportion (30%) of leucocytes expressed L-selectin. CONCLUSIONS: Overall, the results indicate how the degree of L-selectin expression by leucocytes in particular tissues may reflect a requirement for L-selectin expression for entry into those tissues and the activation state of leucocytes once localised there.  相似文献   
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