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S Crawford 《Bulletin of the Medical Library Association》1983,71(1):16-20
Data from three surveys of health sciences libraries in the United States (1969, 1973, and 1979) were analyzed within the context of scientific, technological, and sociopolitical developments. Findings included decrease in the number of separately administered libraries, growth of some, decline or discontinuation of others, and geographic movement. Overall, the aggregate resources are increasing, as is cooperation among libraries. 相似文献
995.
Bibliography of Bioethics and Index Medicus: comparison of coverage, publication delay, and ease of recall for journal articles on bioethics 总被引:1,自引:0,他引:1
S S Marsh 《Bulletin of the Medical Library Association》1987,75(3):248-252
Citations selected from the bibliographies of recent texts, a specialized subject bibliography, and review articles were checked in both Cumulated Index Medicus (IM) and the Bibliography of Bioethics (BB) to compare coverage, publication delay, probable causes of indexing and retrieval failure, and the ease with which relevant citations were retrieved. The study also attempted to determine whether BB included appropriate articles from the MEDLINE database in a timely and systematic manner. While 98% of the IM citations appeared within a year of publication, 79% of the BB citations appeared two to three years after their publication dates. The average citation appeared twice as frequently in IM as in BB. 相似文献
996.
Twenty domestic Muscovy ducks were trained to traverse a runway for food reward. Subjects were then randomly assigned to treatments. In one treatment, subjects received six nonrewarded trials followed by six rewarded trials every day for 12 days; and, in the other treatment, subjects received six rewarded trials followed by six nonrewarded trials every day for 12 days. These successive acquisition and extinction (SAE) treatments were selected because different extinction rates on the nonrewarded trials are expected on the bases of previous research performed with rats. Analyses of variance revealed the former treatment yielded significantly greater resistance to extinction than did the latter treatment. It was concluded that ducklings performed similarly to rats in the above SAE situation. 相似文献
997.
This paper describes the implementation of the Stanford Public Information and Retrieval System (SPIRES) by the University of Michigan Medical School Learning Resources Center. SPIRES is a bibliographic data base management system which offers on-line search capabilities and retrieval of data in programmable formats. The Learning Resource Center utilizes SPIRES for the interactive retrieval of cataloging data, bibliographical compilations, and book catalog production. 相似文献
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Robert S. Siegler 《Contemporary educational psychology》1982,7(3):272-288
This paper describes the rule-assessment approach to cognitive development and summarizes work using it that is relevant to education. The basic question that motivated the rule-assessment approach is how people's existing knowledge influences their ability to learn. Addressing this issue requires a means of assessing what people already know, a means for studying how they learn, and a means for examining basic processes that may underlie developmental differences in knowledge and learning. Research using the rule-assessment approach is summarized in terms of eight conclusions about these issues. Each of the conclusions is illustrated with empirical examples. 相似文献
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