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51.
Medicine has made increasing use of meta-analysis, largely as a quantitative procedure for combining results of clinical trials. Meta-analysis begins with a comprehensive review of the literature. The next step is a systematic analysis of the quality and content of each study. Finally, results are combined statistically and conclusions are drawn from this new overview of the data. This paper presents a brief historical perspective on the use of meta-analysis in medicine with emphasis on the medical library. The authors conclude that in the future, medical librarians will play a significant role in the application of this useful technique. 相似文献
52.
This investigation was undertaken in an effort to establish physiological characteristics of soccer players and to relate them to positional roles. A total of 135 footballers (age 24.4 +/- 4.6 years) were assessed for body mass, % body fat, haemoglobin, maximal oxygen uptake (VO2 max), leg power, anaerobic capacity and speed prior to an English league season. The sample included 13 goalkeepers, 22 full-backs, 24 centre-backs, 35 midfield players and 41 forwards. The goalkeepers were significantly heavier (86.1 +/- 5.5 kg; P < 0.01) than all groups except the centre-backs, had significantly higher estimated body fat percentages than centre-backs, forwards, midfield players (P < 0.01) or full-backs (P < 0.05), significantly lower estimated VO2 max values (56.4 +/- 3.9 ml kg-1 min-1; P < 0.01) and were slowest over 60 m (12.71 +/- 0.42 s). The midfield players had the highest predicted VO2 max values (61.4 +/- 3.4 ml kg-1 min-1), this being significantly greater (P < 0.05) than for the centre-backs. The forwards were the fastest group over 60 m (12.19 +/- 0.30 s), being significantly quicker than goalkeepers or centre-backs (P < 0.01) and full-backs (P < 0.05). Anaerobic power, as well as knee extensor torques (corrected for body mass) and extensor-flexor ratios, were similar between groups. No difference in estimated body fat percentage was observed between any of the outfield players, and haemoglobin concentrations were similar among players of all positions.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
53.
John Marshall is best remembered asthe first resident director of the RockefellerFoundation's Study and Conference Center atBellagio. Yet, his influence on knowledge,thought, and practice rivalled that of any ofhis contemporaries at the Rockefeller. Thispaper describes how he `went about hisbusiness' as a Foundation officer, and examineshis contribution to the creation of atransatlantic community of like-mindedtheorists and practitioners of communications. 相似文献
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Nick Moore 《Cultural Trends》2004,13(1):27-57
Public libraries tend to be taken for granted. They can be found in nearly every community and are used by a substantial proportion of the population, particularly the young and the old. Yet the public library service, as it is today, is a relatively recent phenomenon. Despite their origins in the mid-19th century, the widespread network of public libraries is largely the product of the post-war welfare state. The demand for the service grew rapidly during the war and in the immediate post-war period. Provision to meet the demand was constrained initially by the competing demands for reconstruction, but by 1960 the service was ready to expand. The growth was consolidated by the 1964 Public Libraries and Museums Act and was given further emphasis by the 1962 Bourdillon standards (Ministry of Education, 1962). The Act and the standards provided the impetus for what might be described as the golden age of public libraries. This brief period was brought to an abrupt end by the economic crises of the mid-1970s and the subsequent downward pressure on public expenditure. The service managed to hold its own during the late 1970s and early 1980s but since then it has been in decline, with the rate of decline accelerating during the 1990s as new requirements and increasing costs stretched diminishing resources even further, to the point where the overall level of provision now falls well short of the basic standards that were considered to be essential in the early 1960s. 相似文献
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GARRETT J. McAULIFFE 《Counselor Education & Supervision》1992,31(3):163-174
A case presentation method of group supervision, as practiced at a community college, is described. Developmental principles underlying this approach are presented. 相似文献
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