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341.
The acquired immune deficiency syndrome (AIDS) has rapidly become the most serious medical consequence of injecting illicit drugs. Its potential impact on intravenous (IV) drug use is enormous. Human immunodeficiency virus (HIV, also known as HTLV-III and LAV), the virus that causes AIDS, appears, usually, to lead to lifelong infection. At present there is no effective treatment, and the treatments under development may require lifelong antiviral therapy. Since most of the antibody produced in response to HIV infection does not neutralize the virus, and since there is substantial genetic variation in the virus, it will be difficult to develop a vaccine. Even after vaccines are developed, testing their safety and efficacy will be formidable problems. Until either effective treatment or vaccines are developed, control of the epidemic among IV drug users must be attempted through behavior change/prevention efforts. In this paper we will review the epidemiology of AIDS among IV drug users and characteristics of the IV drug-use subculture relevant to prevention efforts. We will then identify different target groups for these prevention efforts, present available evidence about behavior change in these groups, and then briefly discuss how to prevent transmission of HIV to heterosexual partners who are not themselves IV drug users and to the children of IV drug users.  相似文献   
342.
A perceptual reinforcement theory of stereotyped movements is advanced by Lovaas, Newsom, and Hickman (1987) in an effort to integrate a number of diverse observations about the origins and maintenance of this behavior. We, in turn, argue that the theory, as presented, is logically flawed and fails to take into account important biological findings and theory concerning pathological stereotyped acts. An alternative theory, derived primarily from neurological concepts, is briefly described.  相似文献   
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We examined the effects of a peer initiation intervention with high- and low-status nonhandicapped students on the behavior of untrained peers toward handicapped students. In the context of a counterbalanced withdrawal design, high- and low-status nonhandicapped students were taught to direct social initiations to eight severely handicapped students during recess activities. The interactions of the high-status students resulted in higher levels of initiations by untrained peers toward the handicapped students than did the interactions of the low-status students. Social response levels were also differentially affected by the status of the peer initiator.  相似文献   
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Psychology as both a science and a profession has been closely identified with other disciplines in the broad field of health since the turn of the century. Recent advances in health care have reinforced the growing belief that the promotion of health and the prevention and treatment of illness can be greatly enhanced by incorporating the scientific findings and modern technology of psychology into everyday practices. Outlining the contributions of psychology to health care throughout the world is the primary purpose of this report. In this brief survey, only some of the most timely and relevant issues can be mentioned, together with examples of current work in the field. The reader interested in pursuing these psychological contributions more thoroughly is encouraged to review pertinent references from the citations at the end of this report. After an introductory overview, special attention is given to each of the major areas within the broad field of health care where psychological applications have been particularly useful.  相似文献   
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Two experiments investigated the effect of encoding conditions and type of test (recall vs. recognition) on the phenomenon of hypermnesia (improved performance across repeated tests). Subjects in Experiment 1 studied a list of words using either imaginal or semantic elaboration strategies and then received three successive tests. Different groups of subjects received either free recall, four-alternative forced-choice recognition, or yes/no recognition tests. Reliable hypermnesia was found only in the recall conditions, with the recognition conditions showing either no change in performance levels across tests (forced-choice tests) or significant forgetting (yes/no tests). In Experiment 2, subjects studied a list of words, and encoding was manipulated using three orienting tasks. Once again, hypermnesia was found with the recall tests but not with the forced choice recognition tests. Finding hypermnesia in recall but not in recognition indicates that retrieval processes in recall play a major role in producing hypermnesia. Also, the finding that the magnitude of the recall hypermnesias increased with an increase in total cumulative recall levels across study conditions suggests that cumulative recall levels are an important factor in determining the presence or absence of recall hypermnesia.  相似文献   
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