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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   
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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   
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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   
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The purpose of this study was to determine test-retest reliability for the 1-mile, 3/4-mile, and 1/2-mile distance run/alk tests for children in Grades K-4. Fifty-one intact physical education classes were randomly assigned to one of the three distance run conditions. A total of 1,229 (621 boys, 608 girls) completed the test-retests in the fall (October), with 1,050 of these students (543 boys, 507 girls) repeating the tests in the spring (May). Results indicated that the 1-mile run/walk distance, as recommended for young children in most national test batteries, has acceptable intraclass reliability (.83 less than R less than .90) for both boys and girls in Grades 3 and 4, has minimal (fall) to acceptable (spring) reliability for Grade 2 students (.70 less than R less than .83), but is not reliable for children in Grades K and 1 (.34 less than R less than .56). The 1/2 mile was the only distance meeting minimal reliability standards for boys and girls in Grades K and 1 (.73 less than R less than .82). Results also indicated that reliability estimates remained fairly stable across gender and age groups from the fall to spring testing periods, with the exception of the noticeably improved values for Grade 2 students on the 1-mile run/walk test. Criterion-referenced reliability (P, percent agreement) was also estimated relative to Physical Best and Fitnessgram run/walk standards. Reliability coefficients for all age group standards were acceptable to high (.70 less than P less than .95), except for Fitnessgram standards for 5-year-old girls on the 1-mile test for both fall and spring and for 6-year-old boys and girls on the 1-mile test administered in the spring.  相似文献   
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The many challenges faced by health sciences libraries of all types and sizes often require innovative solutions. When an innovative solution involves calculated risk taking, the approach is called intrapreneurial. At the University of Miami School of Medicine, an intrapreneurial approach solved the fiscal problems of the biomedical communications unit. The Louis Calder Memorial Library inherited these problems when the Department of the Library and Biomedical Communications was created in the early 1980s. In this paper, two intrapreneurial programs are described, and the benefit and suitability of this management style to information services are demonstrated.  相似文献   
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S. Ramasesha 《Resonance》2009,14(8):782-798
Efficient lighting and display have become important concerns in the energy-starved modern world. This has led to new paradigms in lighting and display technologies. Organic molecules provide a new class of active materials for such technologies. This article gives the basic science behind the design of such molecular materials used in displays and lighting.  相似文献   
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