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Atlas MC 《Medical reference services quarterly》2001,20(1):11-25
Physicians are becoming aware of the World Wide Web as a resource for medical information. In spring 1999, first-year students at the University of Louisville's School of Medicine were given an assignment to review and evaluate Internet search engines and directories, medicine-specific search engines and meta lists, and health-related Web sites. Students found that general search engines were easier to learn and use and produced better results than either meta medical sites or medicine-specific search engines. Students were very severe in judging the quality of health-related Web sites. Our students' impressions are compared to those of physicians in similar studies. Solutions to the problems of searching the Web for health information are reviewed. 相似文献
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Research into the physiology of exercise and kinanthropometry is intended to improve our understanding of how the body responds and adapts to exercise. If such studies are to be meaningful, they have to be well designed and analysed. Advances in personal computing have made available statistical analyses that were previously the preserve of elaborate mainframe systems and have increased opportunities for investigation. However, the ease with which analyses can be performed can mask underlying philosophical and epistemological shortcomings. The aim of this review is to examine the use of four techniques that are especially relevant to physiological studies: (1) bivariate correlation and linear and non-linear regression, (2) multiple regression, (3) repeated-measures analysis of variance and (4) multi-level modelling. The importance of adhering to underlying statistical assumptions is emphasized and ways to accommodate violations of these assumptions are identified. 相似文献
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In this study, we examined the patterns of goal orientations, perceived competence, reasons for behaving well and self-reported discipline in school physical education among 511 pupils from years 8 and 9 (mean age 14.2 years). Cluster analyses were conducted on two randomly split subsamples to identify homogeneous groups of pupils on these measures of achievement motivation and discipline. Three meaningful clusters emerged for the first subsample, which were then cross-validated for the second subsample. One group of pupils revealed low scores on task and ego orientations, perceived competence and feelings of self-determination about their behaviour in lessons. These perceptions were related to lower ratings of discipline in physical education than pupils who scored more highly on these variables. The highest discipline scores were reported by pupils with high task and ego orientations, perceived competence and feelings of autonomy. The results are useful for teachers and other physical activity leaders in enhancing motivation and disciplined behaviour in young people. Promoting more self-determined reasons for being disciplined, for example, could lead to more orderly classes. 相似文献
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The aim of this study was to assess the influence of three imposed crank rates on the attainment of peak oxygen consumption (VO2peak) and other physiological responses during incremental arm crank ergometry. Twenty physically active, although non-specifically trained, males volunteered for the study. They completed an exercise protocol using an electrically braked arm ergometer (Lode Angio, Groningen, Netherlands) at crank rates of 60, 70 and 80 rev x min(-1). The order of tests was randomized and they were separated by at least 2 days. Peak VO2 was significantly higher (P < 0.05) at 70 and 80 rev x min(-1) than at 60 rev x min(-1). Peak ventilation volume increased as a function of crank rate and was higher (P < 0.05) at 80 than at 60 rev x min(-1). Peak heart rate was higher (P < 0.05) at 70 and 80 rev x min(-1) than at 60 rev x min(-1). Furthermore, 70 and 80 rev x min(-1) resulted in an extended test time compared with 60 rev x min(-1). The greater physiological responses observed during the tests at the two faster crank rates might have been the result of a postponement of acute localized neuromuscular fatigue, allowing for more work to be completed. We recommend, therefore, that an imposed crank rate between 70 and 80 rev x min(-1) should be used to elicit VO2peak and other physiological responses in arm crank ergometry. 相似文献
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