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251.
OBJECTIVES: Medicine must keep current with the research literature, and keeping current requires continuously updating the clinical knowledge base (i.e., references that provide answers to clinical questions). The authors estimated the volume of medical literature potentially relevant to primary care published in a month and the time required for physicians trained in medical epidemiology to evaluate it for updating a clinical knowledge base. METHODS: We included journals listed in five primary care journal review services (ACP Journal Club, DynaMed, Evidence-Based Practice, Journal Watch, and QuickScan Reviews). Finding little overlap, we added the 2001 "Brandon/Hill Selected List of Print Books and Journals for the Small Medical Library." We counted articles (including letters, editorials, and other commentaries) published in March 2002, using bibliographic software where possible and hand counting when necessary. For journals not published in March 2002, we reviewed the nearest issue. Five primary care physicians independently evaluated fifty randomly selected articles and timed the process. RESULTS: The combined list contained 341 currently active journals with 8,265 articles. Adjusting for publication frequency, we estimate 7,287 articles are published monthly in this set of journals. Physicians trained in epidemiology would take an estimated 627.5 hours per month to evaluate these articles. CONCLUSIONS: To provide practicing clinicians with the best current evidence, more comprehensive and systematic literature surveillance efforts are needed.  相似文献   
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Current information and evidence indicate that for most activities free weight training can produce superior results compared to training with machines, particularly when the free weight training involves complex, multi-joint exercises. A number of reasons can account for the superiority of free weights; the major factor deals with mechanical specificity. Mechanical specificity is concerned with appropriate movement patterns, force application and velocity of movement. Considering the available evidence that adherence to the concept of specificity of exercise and training can result in a greater transfer of training effect then free weights should produce a more effective training transfer. Therefore, the majority of resistance exercises making up a training programme should include of free weight exercises with emphasis on mechanical specificity (i.e. large muscle mass exercises, appropriate velocity, contraction type etc.). Generally, machines should be used as an adjunct to free weight training and, depending upon the sport, can be used to a greater or lesser extent during various phases of the training period (preparation, pre-competition, competition).  相似文献   
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The purpose of this study was to determine whether there is a significant difference in the co-efficient of friction (Fc) between old versus new wrestling shoes and mats and to investigate the effect of perspiration. Fc was measured by dragging a weighted shoe over a wrestling mat surface and measuring the vertical and horizontal forces produced. Three different shoe conditions were assessed over two mat types for both wet and dry conditions for a total of 12 conditions. To simulate the wet condition, saline solution was smeared over the surface of the mat. There was a significant effect of shoe, mat, and wet/dry conditions. In addition, significant interactions of shoe by mat, shoe by dry/wet, and mat by dry/wet were observed. Overall, Fc was 36% higher for the new wrestling mat compared to the old wrestling mat. Application of the saline solution reduced Fc by 14% compared to the dry condition. Comparison of the mean Fc for all three shoe types revealed the Fc for the older design shoe was 23% to 28% lower than the brand new shoe and the worn newer design, respectively. A high Fc, such as in the new mat/new shoe combination, has the potential to increase the risk of knee and ankle injuries by fixing the foot more securely to the ground.  相似文献   
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This research examined varying levels of physical activity and psychomotor and physiological function in variously active older men. Very active moderately active, and low active participants were tested on simple (SRT) and choice reaction time (CRT), coincidence-anticipation timing (CAT), and VO2max. No significant differences for age or height were found, although percentage of fat, and weight were statistically different. Active groups were leaner and lighter. VO2max was significantly different between groups, as physically active groups yielded geater values. SRT and CAT also yielded significantly different results with more active participants showing better performance. No between-groups significant differences resulted for CRT. Generally, increased levels of physical activity were related to superior physiological outcomes and improved psychomotor peformance.  相似文献   
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Book reviews     
Communicating Research by A. J. Meadows Academic Press, 1998. Pp. 256. Hardback, £39.95. ISBN 0.12487415-0  相似文献   
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Michael Farrell, Education Inspector with the London Borough of Hillingdon Education Services, suggests that the term 'mainstream inclusion' should be replaced by 'educational inclusion' in order to avoid the implication that venues other than mainstream schools are inferior. He argues that the placement of pupils with SEN in mainstream schools should be informed by a consideration of the effectiveness of the venue in raising academic and personal and social standards.  相似文献   
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The multilingual roots of Switzerland and especially the bilingual roots of the city and canton of Freiburg are described. So also are the history and structure of the bilingual University of Freiburg which has the particularity of being aimed at providing all its students with a bilingual academic background. The development of bilingual studies and degrees is briefly discussed along with the opportunities available. On the one hand, there are clearly defined and quantified diplomas; on the other hand, the choice of attending several courses in the second language, but of taking examinations in the primary language. Between the two extremes — the definition of bilingual diplomas on the one hand and several special courses on the other — there is a wide range of ways to achieve academic bilingualism. Finally, basic principles for the operation of a multilingual university are proposed.  相似文献   
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