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51.
The National Library of Medicine has had an enormous impact on health information services all over the world. Although NLM is primarily a national institution, it has become an important international resource by responding to requests from the international community. NLM has been influential in three major ways. First, NLM has provided a model for other national and regional health information services. Second, it has been a catalyst, in that MEDLARS and other services it provides formed the nucleus of many regional networks. NLM helped such networks get started by giving advice on how to set up services and build collections and by "training the trainers" on the MEDLARS system. Third, NLM has supported national and regional operations by providing the additional training and materials needed for day-to-day service. 相似文献
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V H Holtz 《Journal of the Medical Library Association》1986,74(4):305-314
Questions concerning some of the values we hold as librarians and the goals, standards, and other evaluation tools we derive from them are discussed in the context of the history of our profession and the present period of rapid change. The concepts of stable and changing paradigms and of "scientific communities" provide the foundation for consideration of how a changing conceptual framework can affect values and their application in the evaluation process. One of many possible scenarios for the future is briefly outlined to demonstrate how some traditional values may fare. 相似文献
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"Change" is a critical dimension of contemporary experience. Library associations are not exempt, and they change in ways similar to other organizations. According to some authorities, four phases typify the process: diagnosis, design, implementation, and incorporation. Focusing on changes in the Medical Library Association's longstanding program of continuing education, the authors utilize the "phase framework" to chart that association's movement from a management system depending primarily upon volunteers to one in which professional staff figure prominently. The historical review serves a heuristic purpose for individuals and institutions in identifying characteristic features of the change process. 相似文献
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Time series analysis was used to investigate the hypothesis that during acquisition of a motor skill, knowledge of results (KR) information is used to generate a stable internal referent about which response errors are randomly distributed. Sixteen subjects completed 50 acquisition trials of each of three movements whose spatial-temporal characteristics differed. Acquisition trials were either blocked, with each movement being presented in series, or randomized, with the presentation of movements occurring in random order. Analysis of movement time data indicated the contextual interference effect reported in previous studies was replicated in the present experiment. Time series analysis of the acquisition trial data revealed the majority of individual subject response patterns during blocked trials were best described by a model with a temporarily stationary, internal reference of the criterion and systematic, trial-to-trial variation of response errors. During random trial conditions, response patterns were usually best described by a "White-noise" model. This model predicts a permanently stationary, internal reference associated with randomly distributed response errors that are unaffected by KR information. These results are not consistent with previous work using time series analysis to describe motor behavior (Spray & Newell, 1986). 相似文献
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