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Criteria for classification of S.L.E   总被引:1,自引:0,他引:1  
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In order to evaluate the incidence and risk factors of infection by hepatitis C virus (HCV) among injecting drug users (IDUs), we conducted a prospective cohort study of HCV- and human immunodeficiency virus (HIV)-negative IDUs in the North and East of France. A total of 231 HCV and HIV IDUs who had injected drugs at least once in their lifetime were followed up every 3 months over a 12-month period. Serum anti-HCV and anti-HIV were tested at inclusion in the study and at the end of the follow-up. Data on injecting practices were collected at inclusion and at each visit. Of the 231 participants included, 165 (71.4%) underwent a final HCV and HIV serum test. The incidence was nil for HIV infection and 9/100 person-years (95% CI 4.6-13.4) for HCV infection. In a multivariable analysis, we found that syringe and cotton sharing were the only independent predictive factors of HCV seroconversion.  相似文献   
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Independent risk factors for fracture include advanced age, preexisting fractures, and low bone mineral density. Rised-ronate has been shown in several large trials to be safe and effective for patients with osteoporosis, but its effects in populations at high risk are not well characterized. To determine the effect of risedronate on vertebral fracture in high-risk subjects, we pooled data from two randomized, double-blind studies [Vertebral Efficacy with Risedronate Therapy (VERT) Multinational (VERT-MN) and VERT-North America (VERT-NA)] in 3684 postmenopausal osteoporotic women treated with placebo or risedronate 2.5 or 5 mg/d and analyzed fracture risk in subgroups of subjects at high risk for fracture due to greater age or more prevalent fractures (vs. median for overall study population), or lower bone mineral density (T-score, -2.5 or less). Fractures were diagnosed by quantitative and semiquantitative assessment of radiographs at baseline and 1 yr. In the overall population, treatment for 1 yr with risedronate 5 mg/d reduced the risk of new vertebral fractures by 62% vs. control (relative risk, 0.38; 95% confidence interval, 0.25, 0.56; P < 0.001) and of multiple new vertebral fractures by 90% vs. control (relative risk, 0.10; 95% confidence interval, 0.04, 0.26; P < 0.001). Consistent risk reductions were observed at 1 yr in the risedronate-treated high-risk subgroups. Significant reduction in fracture risk after 1 yr is an important benefit in patients at high risk for fracture because, without treatment, these patients are likely to sustain new fractures in the near term.  相似文献   
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Context  The worldwide explosive increase in type 2 diabetes mellitus and its cardiovascular morbidity are becoming major health concerns. Objective  To evaluate the effect of decreasing postprandial hyperglycemia with acarbose, an -glucosidase inhibitor, on the risk of cardiovascular disease and hypertension in patients with impaired glucose tolerance (IGT). Design, Setting, and Participants  International, multicenter double-blind, placebo-controlled, randomized trial, undertaken in hospitals in Canada, Germany, Austria, Norway, Denmark, Sweden, Finland, Israel, and Spain from July 1998 through August 2001. A total of 1429 patients with IGT were randomized with 61 patients (4%) excluded because they did not have IGT or had no postrandomization data, leaving 1368 patients for a modified intent-to-treat analysis. Both men (49%) and women (51%) participated with a mean (SD) age of 54.5 (7.9) years and body mass index of 30.9 (4.2). These patients were followed up for a mean (SD) of 3.3 (1.2) years. Intervention  Patients with IGT were randomized to receive either placebo (n = 715) or 100 mg of acarbose 3 times a day (n = 714). Main Outcome Measures  The development of major cardiovascular events (coronary heart disease, cardiovascular death, congestive heart failure, cerebrovascular event, and peripheral vascular disease) and hypertension (=" BORDER="0">140/90 mm Hg). Results  Three hundred forty-one patients (24%) discontinued their participation prematurely, 211 in the acarbose-treated group and 130 in the placebo group; these patients were also followed up for outcome parameters. Decreasing postprandial hyperglycemia with acarbose was associated with a 49% relative risk reduction in the development of cardiovascular events (hazard ratio [HR], 0.51; 95% confidence interval [CI]; 0.28-0.95; P = .03) and a 2.5% absolute risk reduction. Among cardiovascular events, the major reduction was in the risk of myocardial infarction (HR, 0.09; 95% CI, 0.01-0.72; P = .02). Acarbose was also associated with a 34% relative risk reduction in the incidence of new cases of hypertension (HR, 0.66; 95% CI, 0.49-0.89; P = .006) and a 5.3% absolute risk reduction. Even after adjusting for major risk factors, the reduction in the risk of cardiovascular events (HR, 0.47; 95% CI, 0.24-0.90; P = .02) and hypertension (HR, 0.62; 95% CI, 0.45-0.86; P = .004) associated with acarbose treatment was still statistically significant. Conclusion  This study suggests that treating IGT patients with acarbose is associated with a significant reduction in the risk of cardiovascular disease and hypertension.   相似文献   
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Transmission of syphilis between sexual partners in Gabon.   总被引:2,自引:1,他引:1       下载免费PDF全文
The prevalence and transmission of syphilis was studied in a semirural community in south eastern Gabon. The overall prevalence was 8% (99/1251) and there was no difference in age adjusted prevalence between men and women. The transmission of syphilis between sexual partners occurred in 18.1% (8/44).  相似文献   
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PURPOSE: The precise determination of skin's mechanical properties is still an open question. When performing an in vivo test, the piece of skin tested is not as well defined as it is in material testing. Moreover, the body zone and the body posture imply an initial stress on the skin. Consequently, a precise mechanical analysis needs a precise measurement of the natural skin tension. METHODS: A new method and the relative device are presented. It is based on an extensiometry test. Skin is tested not only in traction but also in compression. The tested skin sample is well defined and protected from surrounding effects by follower tabs. The size and shape of the device have been optimised by a finite element modelisation. RESULTS: The method was tested with elastomers pre-tensioned at different loads. It is shown that the initial tension can be retrieved with good precision. Tests were then performed in vivo on the forearm for different arm positions. It is shown that initial tension could be only clearly determined for the highest skin tension, although the skin presented very different traction behaviour with different arm positions. CONCLUSION: It is shown how body posture influences measurements. An innovative method for easily determining initial tension is presented. Nevertheless, further tests and device improvements are needed to apply this skin tension measurement for different body zones and body postures.  相似文献   
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Summary Background Human immunodeficiency virus (HIV) infection generally induces lipodystrophy. For targeted treatment a better understanding of its development is necessary. The utility of high‐resolution magnetic resonance imaging (MRI) is explored. Objectives The present study presents a way to visualize the adipose tissue architecture in vivo and to inspect modifications associated with the atrophy. Methods High‐resolution MRI scans with surface coils were performed on the calf and at the lumbar region of three groups of patients: HIV patients with lipoatrophy, HIV patients without lipoatrophy and healthy volunteers. All patients underwent a clinical examination. In addition, dual energy X‐ray absorptiometry (DEXA) measurements were taken. On the MRI scans adipose tissue thickness and adipose nodule size were measured. Results High‐resolution MRI enabled identification of a clear disorganization of adipose tissue in patients with lipoatrophy. In addition, these patients presented a very small adipose tissue thickness on the calf and a very small nodule size. Results led to the hypothesis that adipose tissue disorganization appears before changes in DEXA measurements or clinically visible modifications. Conclusions High‐resolution MRI enabled visualization in vivo of precise changes in tissue organization due to HIV lipoatrophy. This imaging technique should be very informative for better monitoring of the atrophy.  相似文献   
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