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101.
Performance of commercially available enzyme immunoassays for detection of antibodies against herpes simplex virus type 2 in African populations 总被引:7,自引:0,他引:7
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van Dyck E Buvé A Weiss HA Glynn JR Brown DW De Deken B Parry J Hayes RJ 《Journal of clinical microbiology》2004,42(7):2961-2965
Data are accumulating on the performance of enzyme immunoassays (EIAs) for the detection of herpes simplex virus type 2 (HSV-2) infection in North America and Europe, but little is known about their performance in other populations. Nine test kits were evaluated with 330 serum samples from sub-Saharan Africa. The tests were first compared to the monoclonal antibody (MAb) EIA (Central Public Health Laboratory, London, United Kingdom). Samples that gave discordant results in the MAb EIA and in the three tests that performed best compared to the MAb EIA were tested by Western blotting (University of Washington, Seattle). A random sample of concordant samples was also tested, and the sensitivities and specificities of the different tests were calculated, taking into account this sampling strategy. The sensitivities of the tests ranged from 86 to 100%; the specificities ranged from 47 to 99%. The tests that performed best were the Gull Premier EIA (sensitivity, 86.3%; specificity, 97.6%) and the Kalon Biological (sensitivity, 92.3%; specificity, 97.7%) and Biokit (sensitivity, 86.7%; specificity, 92.6%) tests. It cannot be assumed that enzyme immunoassays for the detection of HSV-2 infection that perform well in industrialized countries will perform equally well in other populations. 相似文献
102.
ABO and Rh(D) phenotype frequencies of different racial/ethnic groups in the United States 总被引:1,自引:0,他引:1
BACKGROUND: Commonly quoted ABO/Rh(D) frequencies in the US are usually from relatively small studies with racial or ethnic categories often judged by name or appearance. STUDY DESIGN AND METHODS: A 10-year demographic database that contained racial or ethnic and ABO/Rh(D) phenotype data on 3.1 million allogeneic and autologous donors giving blood at five blood centers in the US was used to compute ABO and Rh(D) phenotypes in various racial/ethnic groups. The racial or ethnic category was designated by the donor. RESULTS: The highest percentage of Group O was found in Hispanic (56.5%), North American Indian (54.6%), and black non-Hispanic (50.2%) donors. Hispanic and black non-Hispanic donors had a much lower percentage (7.3 and 7.1%, respectively) of Rh- compared to white non-Hispanic donors (17.3%). Group O Rh- and Group B Rh- were found more commonly (8.0 and 1.8%, respectively) in white non-Hispanic donors than in Hispanic (3.9 and 0.7%), black non-Hispanic (3.6 and 1.3%), and Asian (0.7 and 0.4%) donors. CONCLUSIONS: These data confirmed that the highest percentages of ORh+, BRh+/ABRh+, and Rh- are present in Hispanic, Asian, and white non-Hispanic donors, respectively. These are the largest and most accurate data of ABO/Rh(D) phenotype frequencies for the major racial/ethnic donor groups in the US. 相似文献
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PURPOSE: To examine the development of age-related cataract in a trial of beta-carotene supplementation in women. METHODS: The Women's Health Study is a randomized, double-masked, placebo-controlled trial originally designed to test the balance of benefits and risks of beta-carotene (50 mg on alternate days), vitamin E, and aspirin in the primary prevention of cancer and cardiovascular disease among 39,876 female health professionals aged 45 years or older. The beta-carotene component of the trial was terminated early after a median treatment duration of 2.1 years. Main outcome measures were visually-significant cataract and cataract extraction, based on self-report confirmed by medical record review. RESULTS: There were 129 cataracts in the beta-carotene group and 133 in the placebo group (relative risk [RR] = 0.95, 95% CI 0.75-1.21). For cataract extraction, there were 94 cases in the beta-carotene group and 89 cases in the placebo group (RR = 1.04, 95% CI 0.78-1.39). Subgroup analyses suggested a possible beneficial effect of beta-carotene in smokers. CONCLUSIONS: These randomized trial data from a large population of apparently healthy female health professionals indicate that two years of beta-carotene treatment has no large beneficial or harmful effect on the development of cataract during the treatment period. 相似文献
107.
Glynn SA Gammell P Heenan M O'Connor R Liang Y Keenan J Clynes M 《British journal of cancer》2004,91(10):1800-1807
Doxorubicin- and paclitaxel-selected variants of an in vitro invasive clonal population of the human breast cancer cell line, MDA-MB-435S, were established by pulse selection, and exhibited a novel 'superinvasive' phenotype. This phenotype is characterised by an ability to relocate to another surface following invasion through matrigel and membrane pores, by decreased adhesion to extracellular matrix proteins and by increased motility. This may represent an in vitro model of a step in the metastatic process occurring subsequent to invasion. The paclitaxel-resistant variants, MDA-MB-435S-F/Taxol-10p and MDA-MB-435S-F/Taxol-10p4p were resistant to paclitaxel, vincristine and docetaxel, but not to doxorubicin, carboplatin, etoposide or 5-fluorouracil. The doxorubicin-selected variants MDA-MB-435S-F/Adr-10p and MDA-MB-435S-F/Adr-10p10p, in contrast, exhibited only small increases in resistance to doxorubicin, although they were slightly resistant to VP-16 and docetaxel, and exhibited increased sensitivity to paclitaxel, carboplatin and 5-fluorouracil. 相似文献
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109.
Sebastian?SchneeweissEmail author Philip?S.?Wang Jerry?Avorn Malcolm?Maclure Raia?Levin Robert?J.?Glynn 《Journal of general internal medicine》2004,19(5):444-450
OBJECTIVE: The performance of standard comorbidity scores to control confounding is poorly defined in health care utilization data across
elderly populations. We sought to evaluate and rank the performance of comorbidity scores across selected U.S. and Canadian
elderly populations using health care utilization databases.
DESIGN: Cross-population validation study. 相似文献
110.
This study examines the association between physical activity and C-reactive protein levels, indicating that high levels of strenuous aerobic activity are associated with lower C-reactive protein levels among men. 相似文献