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91.
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   
92.
What is the future for libraries and their librarians? In trying to give an answer to this pressing question we do not deal with utopian libraries of the next century, but with the library and the librarian of the next decade. The emphasis is on libraries within educational and research institutions, especially university libraries. We examine the changes confronting the library of the future and identify four key aspects of the library of the future. It will be (i) a gateway to information, whatever format this information comes in and wherever it is located; (ii) an expertise centre; (iii) a physical entity, not only in the sense of being a social meeting place and place of scholarly interaction, but also as a place where students and other users are provided with modern study facilities and adequate user support; and (iv) a collection centre of printed material. Such libraries can only take on an appropriate shape and will only survive if the institutions that librarians serve in meet the four criteria outlined above. We look at the demands that will be made on professional library knowledge and skills and the new job responsibilities and job attitudes required.  相似文献   
93.
以广西82名业余体校男运动员为研究对象,运用数理统计方法,探讨了快肌百分比与有关身体素质指标和生理指标的相关程度,以及拟合的指标对快肌百分比的影响,旨在为速度性运动项目的选材提供理论依据。  相似文献   
94.
浅谈体育教学中的语言艺术   总被引:1,自引:0,他引:1  
体育教学语言是教师向学生传授知识的载体,交流情感的方式及培养人才的工具,亦是影响教学效果的重要因素之一.通过对体育教学语言的分类、特点及其运用方法的论述,着重阐明了体育教学语言指令性、调节性和感染性特点;语言修养及教育性、准确性和生动性等要求.  相似文献   
95.
试述现代科学训练的主要特征   总被引:2,自引:0,他引:2  
根据现代运动训练学科的发展趋势,从运动训练的过程、人员机构和外部联系3个主要方面对现代科学训练的特征进行论述.  相似文献   
96.
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   
97.
98.
Chaos theory, informational needs, and natural disasters   总被引:2,自引:0,他引:2  
This study applies chaos theory to a system-wide analysis of crisis communication in a natural disaster. Specifically, we analyze crisis communication during the 1997 Red River Valley flood in Minnesota and North Dakota. This flood, among the worst in modern American history, consumed entire metropolitan areas, displacing thousands of people. The conditions and decisions leading to the disaster, and the subsequent reactions are retraced. Communication related to river crest predictions (fractals), the shock at the magnitude of the crisis (cosmology episode), novel forms of reorganizing (self-organization), and agencies that aided in establishing a renewed order (strange attractors) are evaluated. Ultimately, we argue that preexisting sensemaking structures favoring rationalized, traditional views of a complex system led officials to make inappropriately unequivocal predictions and ultimately diminished the effectiveness of the region's crisis communication and planning.  相似文献   
99.
100.
Ordinary markets allow parties, not the state, to value property and projects. But they do not account for subjective value in such traditional contexts as condemnation. An awareness of these nonmarket values helps overcome any categorical opposition to the use of the contingent valuation method (CVM) to value cultural and environmental resources. But accurate CVM should measure all values, positive or negative, tononowners; it should apply generally to any substitute projects; and it should seek to account for diminishing marginal value of additional resource units. CVM should be used only to aggregate nonmarket preferences, not to skew the political debate to cultural or environmental objectives.  相似文献   
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