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Peng?Dong Ling?Ling?Wong Sarah?Ng Marie?Loh Adrian?MondryEmail author 《BMC medical informatics and decision making》2004,4(1):21
Background
Critically Appraised Topics (CATs) are a useful tool that helps physicians to make clinical decisions as the healthcare moves towards the practice of Evidence-Based Medicine (EBM). The fast growing World Wide Web has provided a place for physicians to share their appraised topics online, but an increasing amount of time is needed to find a particular topic within such a rich repository.Methods
A web-based application, namely the CAT Crawler, was developed by Singapore's Bioinformatics Institute to allow physicians to adequately access available appraised topics on the Internet. A meta-search engine, as the core component of the application, finds relevant topics following keyword input. The primary objective of the work presented here is to evaluate the quantity and quality of search results obtained from the meta-search engine of the CAT Crawler by comparing them with those obtained from two individual CAT search engines. From the CAT libraries at these two sites, all possible keywords were extracted using a keyword extractor. Of those common to both libraries, ten were randomly chosen for evaluation. All ten were submitted to the two search engines individually, and through the meta-search engine of the CAT Crawler. Search results were evaluated for relevance both by medical amateurs and professionals, and the respective recall and precision were calculated.Results
While achieving an identical recall, the meta-search engine showed a precision of 77.26% (±14.45) compared to the individual search engines' 52.65% (±12.0) (p < 0.001).Conclusion
The results demonstrate the validity of the CAT Crawler meta-search engine approach. The improved precision due to inherent filters underlines the practical usefulness of this tool for clinicians.84.
1,25-Dihydroxyvitamin D3 Induces Nitric Oxide Synthase and Suppresses Growth of Mycobacterium tuberculosis in a Human Macrophage-Like Cell Line 总被引:3,自引:0,他引:3 下载免费PDF全文
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Tibor Hortobágyi Joseph A. Houmard Richard G. Israel John W. Carpenter Judy Heath Hisham A. Barakat 《European journal of applied physiology》1993,67(3):226-230
Summary The purpose of this study was to determine the effects of short-term exercise cessation on lipid and lipoprotein profile and insulin sensitivity in highly trained runners (n=12; mean age 19.9 years) and power athletes (n=12; mean age 24.4 years). Following 14 days of exercise cessation, running time to exhaustion and maximal oxygen uptake decreased by 9.2% and 4.8% (P < 0.05) in the runners, while in the power athletes one repetition maximum squat and bench press did not change (P>0.05). No changes occurred in body composition. Data from a 2-h oral glucose tolerance test revealed an impairment of the glycemic state in all athletes (P<0.05). In contrast, exercise cessation did not significantly (P>0.05) alter plasma levels of cholesterol, triglycerides, and low density (LDL) and high density lipoprotein (HDL). No changes were observed in HDL2, HDL2b, and HDL3 subfractions, LDL diameter, and qualitative LDL pattern (P>0.05). These data thus suggest that despite a decrease in insulin sensitivity, short-term exercise cessation, independent of exercise mode, was insufficient to alter plasma lipid and lipoprotein profiles in well-trained athletes. 相似文献
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Summary Five adenovirus 15/Hx and one Ad9/Hx strain with a common novel hemagglutinin were compared serologically and by DNA restriction analysis with six endonucleases with the related prototypes. The five Ad15/Hx strains represented five different genome types.With 1 FigureAided by grants from the Deutsche Forschungsgemeinschaft (Wi 2/21-1), Bundesministerium für Jugend, Familie und Gesundheit, and Förderverein der Deutschen Vereinigung zur Bekämpfung der Viruskrankheiten e. V., FRG. 相似文献
87.
Protection of Chicken Embryos by Viridans Streptococci Against the Lethal Effect of Staphylococcus aureus 总被引:2,自引:0,他引:2 下载免费PDF全文
Raza Aly Howard I. Maibach Henry R. Shinefield Adrian D. Mandel 《Infection and immunity》1974,9(3):559-563
Chicken embryos were used to investigate the mechanism by which viridans streptococci inhibit the growth of pathogenic staphylococci. Ten-day-old embryonated eggs were infected allantoically. At a concentration of 1.8 x 10(2) colony-forming units (CFU) of viridans streptococci, the percentage of fatalities was less than 10%. There was 80% fatality with 8 x 10(1) CFU of Staphylococcus aureus strain 502A and 100% when a 100-fold increase in concentration was used. An inoculum size of 10(2) to 10(3) CFU of viridans streptococci was chosen to protect the embryos against the lethal effect of strain 502A when challenged 24 h later. The survival after challenging at 4 days was 93% in protected eggs and 37% in unprotected eggs. Chicken embryos receiving heat-killed viridans and challenged with strain 502A when examined after 4 days did not demonstrate a protective effect. This protection of embryonated eggs could not be transferred by administration of sterile filtrate of allantoic fluid in which protecting strain was grown. The experimental infection of embryonated eggs has demonstrated that prior allantoic infection with viridans streptococci affords significant protection against subsequent challenge with virulent staphylococci. 相似文献
88.
Sodium currents in mammalian muscle 总被引:1,自引:0,他引:1
1. A method is described which allows the approximate computation of membrane current from measurements with three electrodes in the mid-region of a muscle fibre. 相似文献
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