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51.
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Assessment of cataracts from photographs in the Beaver Dam Eye Study   总被引:8,自引:0,他引:8  
Presence and severity of age-related cataract was determined in adults 43 to 84 years of age in Beaver Dam, Wisconsin. Duplicate photograph gradings for nuclear sclerosis (n = 1160), cortical opacities (n = 1159), and posterior subcapsular cataract (n = 1137) were performed. There are five levels of nuclear sclerosis. Exact agreement occurred in 64.7% of the cases; agreement within one category in 99.8%. For cortical opacities, graders estimate involved area in nine segments of the lens. When the continuous scale is divided into 12 categories of severity, exact agreement varied between 73.5 and 82.4%; for agreement within one category, rates varied between 84.6 and 89.9%. For posterior subcapsular cataracts, exact agreement for involvement of the central circle occurred in 95.0% and agreement within one category occurred in 97.7%. Intraobserver comparisons disclosed similar concordance. These grading schemes are semiquantitative, reproducible, and can be performed for the large numbers of photographs from population-based studies.  相似文献   
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Acute otitis media (AOM) is thought to occur frequently in children infected with human immunodeficiency virus (HIV). We compared experience with AOM of 28 HIV-infected children with that of 33 children who seroreverted to HIV antibody negative status by age 18 months. The mean number of episodes/year of AOM for children who seroreverted decreased from 1.33 in the first year of life to 0.13 in the third year, whereas the mean number of episodes/year in HIV-infected children increased from 1.89 to 2.40. By age 3 years, all HIV-infected children had experienced 1 or more episodes of AOM, and 80% had experienced 6 or more, whereas 75% of children who seroreverted had experienced 1 or more episodes, and none had had 6 or more. HIV-infected children with normal T4 lymphocyte counts had a mean of 1.18 episodes of AOM in the first year of life compared with 2.35 episodes in HIV-infected children with decreased counts (P = 0.023). HIV-infected children with low counts had a nearly 3-fold increased risk of recurrent AOM (47% vs. 18%).  相似文献   
54.
Factors influencing women to undergo screening mammography   总被引:2,自引:0,他引:2  
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The effect of cyclophosphamide pulse therapy given in relatively small doses (10 mg/kg per pulse) in 17 females with lupus nephritis has been studied. Four females developed menopause; in one transient amenorrhea occurred. No changes in menstrual cycle were noted in the other 11 females, four of whom subsequently delivered five normal babies. These data suggest the relative safety of small doses of cyclophosphamide pulse therapy on gonadal function in females under age 40 years.  相似文献   
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Antibodies against neutrophils have been detected in sera from patients with primary sclerosing cholangitis and inflammatory bowel diseases either by immunofluorescence or by enzyme-linked immunosorbent assay. To assess primary sclerosing cholangitis-specific antibodies, we examined sera from 30 patients with clinically and morphologically well-established primary sclerosing cholangitis by Western blotting against neutrophils and compared these results with those obtained by testing sera from patients with inflammatory bowel diseases. By Western blot using sonified neutrophils, 24 (80%) of 30 primary sclerosing cholangitis sera were positive. Five antigenic determinants at 95, 60, 55, 40 and 30 kD were visualized. Twenty-eight of the primary sclerosing cholangitis sera also showed the characteristic perinuclear fluorescence pattern by immunofluorescence on neutrophils. Thus a serological diagnosis of primary sclerosing cholangitis could be made in 80% of patients based on these two methods. In contrast, only 9% of 23 patients with ulcerative colitis and 10% of 60 patients with Crohn's disease were positive by Western blot, and these patients also showed positive perinuclear fluorescence pattern by immunofluorescence, suggesting an overlap between inflammatory bowel diseases and primary sclerosing cholangitis. Although some patients with classical primary biliary cirrhosis and autoimmune chronic active hepatitis had antibodies against primary sclerosing cholangitis epitopes, none of the patients with obstructive bile duct disorders, collagen diseases, Wegener's granulomatosis or other hepatic and nonhepatic disorders were positive by Western blot, indicating the specificity of these five primary sclerosing cholangitis-related neutrophilic epitopes.  相似文献   
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The Toronto Sexual Contact Study comprises a cohort of 249 male sexual contacts of men with HIV disease which has been followed every 3 months for almost 5 years. On enrollment 143 were seropositive and 16 seroconverted during the follow-up period. By 31 December 1989, 41 of the 159 seropositive cohort members had developed AIDS. Using Cox relative risk regression models, we investigated the association of a number of laboratory and clinical variables and progression to AIDS. Fixed covariate models examined laboratory variables from the enrollment visit of cohort members, with time calculated from this date. In models assessing time dependent covariates, time was calculated from the estimated date of HIV infection. In the univariate models of either fixed or time dependent covariates, many variables were significantly associated with risk of progression to AIDS (T4 cell count, T4/T8 ratio, blastogenic responses to phytohemagglutinin, concanavalin A, and pokeweed mitogen, serum IgA, appearance of p24 antigen, and the development of oral hairy leukoplakia, thrush, or herpes zoster). Appearance of persistent generalized lymphadenopathy was not associated with increased risk of progression. In the multivariate model which evaluated fixed laboratory covariates, T4/T8 ratio, IgA level, and PHA response at enrollment were significantly associated with elevated risk.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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