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Quantitative Ultrasound and Mortality: A Prospective Study   总被引:2,自引:0,他引:2  
Previous studies suggest that low bone mineral density (BMD) is associated with increased mortality, but the relationship between quantitative ultrasound (QUS) and mortality is unknown. We studied 5816 women over age 70 years enrolled in the Study of Osteoporotic Fractures. QUS of the calcaneus, and BMD of the calcaneus and hip, were measured at baseline, and women were contacted every 4 months to determine vital status. All reported deaths were confirmed by review of the death certificate or hospital records, and classified by ICD-9 code. During 5.0 years of follow-up, 677 women died. Women in the lowest quintile of QUS had the highest mortality during follow-up. After adjustment for age, grip strength, weight, height, health status, estrogen use, smoking, physical activity, and history of hypertension, diabetes, cardiovascular disease, cancer and stroke, each 1 SD reduction in broadband ultrasonic attenuation (BUA) was associated with a 16% increase in mortality (RH = 1.16; 95% CI: 1.07, 1.26). Mortality from cardiovascular disease, cancer and other causes were all increased among women with low QUS, but the association with cancer deaths was not statistically significant after multiple adjustments (RH = 1.09; CI: 0.93, 1.27). Low BMD was also associated with an increased risk of total and cause-specific mortality, but we found little evidence that BUA and BMD were independent predictors of mortality. Results were similar among women who did not fracture during follow-up. In this large population-based study of older women, low QUS is associated with both total and cause-specific mortality. This relationship was independent of other factors associated with mortality, such as age and health status, and suggests QUS and BMD may reflect some aspect of aging not captured by these traditional factors. Received: 16 March 2001 / Accepted: 19 February 2002  相似文献   
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神经节细胞瘤是一种神经内分泌肿瘤,其发生与自主神经系统的交感或副交感神经节有关。罕见发生于膀胱、前列腺和子宫。本文作者报道1例发生于儿童头皮的原发性皮肤神经节细胞瘤。对此肿瘤进行了组织学、免疫组化和超微结构研究。该病例可能代表神经嵴细胞向鳃弓发育过程中的一种异常迁移。此外,研究结果还强调在胚胎发育过程中神经嵴和鳃弓/裂之间有复杂的相互作用。  相似文献   
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Context  The effect of early antiretroviral therapy (ART) on the early progression of perinatal human immunodeficiency virus (HIV) infection is not well defined. Objective  To examine early disease progression and survival in a population-based cohort with perinatal HIV infection in relation to year of birth and use of ART. Design, Setting, and Patients  Retrospective study of temporal trends in early progression of perinatal HIV infection among 205 HIV-infected children in Northern California born between January 1, 1988, and December 31, 2001, and followed up through age 3 years. Main Outcome Measures  Prevalence of and age at progression to a first US Centers for Disease Control and Prevention category C diagnosis relative to year of birth, type of ART, and age at initiation of therapy. Results  Of 205 children, 134 (65%) received ART and/or Pneumocystis jiroveci pneumonia prophylaxis. By age 3 years, 81 (40%) progressed to a category C diagnosis, 41 (51%) of whom died. Untreated children were significantly more likely to progress to a category C diagnosis (62% [44/71] untreated vs 28% [37/134] treated children, P<.001); none of 23 infants who received triple ART progressed to category C. However, even without triple ART, very early mono/dual ART (by age 2 months vs 3-4 months) was associated with delayed and decreased progression to category C (P = .02). Of 33 children born between January 1, 1996, and December 31, 2001, only 7 (21%) progressed to category C (P = .02 compared with 1988-1995), 6 of 7 of whom received no therapy. More recent year of birth and more advanced therapy were associated with improved survival. Conclusions  This population-based cohort demonstrated decreased early HIV progression and improved survival at age 3 years, associated with more advanced therapy. Although limited by small sample size, the findings suggest that very early treatment, even without triple ART, was associated with improved outcome.   相似文献   
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We examined the association between residential proximity to agricultural pesticide use and breast cancer incidence among members of the California Teachers Study cohort, a large study of professional school employees with extensive information on breast cancer risk factors, followed for cancer incidence since 1995. We identified 1552 invasive breast cancer cases, diagnosed between 1996 and 1999, among 114,835 cohort members. We used California Pesticide Use Reporting data to select pesticides for analysis based on use volume, carcinogenic potential, and exposure potential; a Geographic Information System was used to estimate pesticide applications within a half-mile radius of subjects' residences. We applied Cox proportional hazard models to estimate hazard rate ratios (HR) for selected pesticides, adjusting for age, race, and socioeconomic status. We saw no association between residential proximity to recent agricultural pesticide use and invasive breast cancer incidence. HR estimates for the highest compared to the lowest exposure categories for groups of agents were as follows: probable or likely carcinogens (1.07, 95% confidence interval (CI): 0.86-1.32), possible or suggestive carcinogens (1.06, 95% CI: 0.87-1.29), mammary carcinogens (1.15, 95% CI: 0.90-1.48), and endocrine disruptors (1.03, 95% CI: 0.86-1.25). HR estimates for other groups and individual pesticides did not differ from unity, nor was there a trend for any groupings of or individual pesticides examined. Stratifying by menopausal status or family history of breast cancer did not substantially affect our results. Our analyses suggest that breast cancer incidence is not elevated in areas of recent, high agricultural pesticide use in California.  相似文献   
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Self-reported cancer data from the California Teachers Study were validated by using California Cancer Registry data. The California Teachers Study cohort consists of 133,479 active and retired California teachers. In 1995-1996, data from a mailed questionnaire were linked to the California Cancer Registry data. Sensitivity and specificity of 11 types of cancer were calculated. Multivariate analyses were conducted to evaluate correlates of false-positive and false-negative reporting. Sensitivities showed great variation by cancer site. The highest sensitivities were observed for breast (96.4%) and thyroid (92.9%) cancers, whereas the lowest sensitivities were those for cervical (44.3%), endometrial (69.1%), and other skin (53.6%) cancers. The sensitivities for in situ cancers (at the time of diagnosis) were considerably lower than those for invasive cancers in about half of the cancer types surveyed. The specificities for individual cancer sites ranged from 90% to 99%; the highest were those for lung cancer, leukemia, and Hodgkin's disease (all 99.9%). The lowest specificity was for other skin cancer (90.2%). In situ stage at diagnosis and older age were significantly associated with false-positive reporting. Age and non-White race were associated with false-negative reporting. These findings suggest that the feasibility of using self-reported data without verification in epidemiologic studies of cancer varies by site.  相似文献   
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