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971.
972.
Health professionals are collecting and charting data about the family history of their patients in order to determine if a predisposition to heart, stroke, cancer and other debilitating conditions can be detected or alleviated through patient education and preventive medicine. Family history-taking for the purposes of preventive medicine is introduced, along with a brief history of the field. The pedigree chart and the genogram are described and their use by health personnel is discussed. A brief search strategy on MEDLINE and a selected bibliography are presented to aid the health sciences librarian to find information on the family history, genograms or pedigree charts.  相似文献   
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This paper provides an overview of the National Health Service in England, including its history, its present structure, and factors that make it different from the U.S. health care system. The NHS libraries and librarians are discussed. The NHS is divided into fourteen regions in England. Three specific NHS libraries in the Wessex region are described--a hospital library, an administrative library, and a patient education library. The problems and accomplishments of NHS librarians are discussed, as well as some similarities between NHS libraries and U.S. medical libraries. Medical librarians are urged to try to understand the medical library scene in England, so that they can Learn from the unique strengths of their counterparts there.  相似文献   
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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   
980.
Requests for monographs generated within an interlibrary loan network are analyzed for half-life statistics. It is suggested that demand represents use of the literature more completely than satisfied requests or circulation statistics. Demand in this study is characterized as either regional demand or statewide demand and is related to the level of the network where final processing of the request occurs. A negative exponential distribution is found to adequately characterize both levels of demand as a function of publication date for four subject categories. Corrected demand data is obtained by removing the growth rate of most of the available literature represented by American book publisher output. Based on over 10,000 interlibrary loan requests, negative exponential distributions describe the raw data as well as the corrected data. A shorter half-life was found for regional library demand (10.47 yr) than that found for statewide library demand (15.75 yr). Applying the correction factor to reflect the growth rate of the available literature tends to increase the half-life when compared to the raw data, and changes the ordering of subject classes with respect to ascending half-lives.  相似文献   
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