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241.
Although the ability to perform gene therapy in human germ-line cells is still hypothetical, the rate of progress in molecular and cell biology suggests that it will only be a matter of time before reliable clinical techniques will be within reach. Three sets of arguments are commonly advanced against developing those techniques, respectively pointing to the clinical risks, social dangers and better alternatives. In this paper we analyze those arguments from the perspective of the client-centered ethos that traditionally governs practice in medical genetics. This perspective clarifies the merits of these arguments for geneticists, and suggests useful new directions for the professional discussion of germ-line gene therapy. It suggests, for example, that the much discussed prospect of germ-line therapy in human pre-embryos may always be more problematic for medical genetics than adult germ-line interventions, even though the latter faces greater technical difficulties.  相似文献   
242.
Three supervisors of integrated preschools were trained in a collaborative team approach to encourage resource and classroom teachers to develop strategies that promote peer interaction of all children, including children with disabilities. The focus of classroom teachers' behaviors and the interactive play of children with disabilities were measured daily in both a training (indoor play period) and a generalization (outdoor play period) setting. In a multiple baseline design, supervisors were individually trained in a collaborative team approach using a manual, modeling, and role playing; then they implemented the approach with classroom and resource teachers. We found that after supervisor training, classroom teachers increased their behaviors directed towards children with disabilities and decreased their behaviors directed towards nondisabled children. Moreover, we found a doubling of the interactive play of children with disabilities and, for two of the three classes, an increase in the interactive play of comparison children, randomly selected by the classroom teachers. Changes in both teachers' and children's behaviors were also found in the generalization setting. The implications of the results for interventions in community settings are discussed.  相似文献   
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Previous papers on ethics consultation in medicine have taken a positivistic approach and lack critical scrutiny of the psychosocial, political, and moral contexts in which consultations occur. This paper discusses some of the contextual factors that require more careful research. We need to know more about what prompts and inhibits consultation, especially what factors effectively prevent house officers and nonphysicians from requesting consultation despite perceived moral conflict in cases. The attitudes and institutional power of attending medical staff seem important, especially where innovative interventions raise ethical questions. Ethics consultants also need to address the thorny problems of the origin(s) of the consultant's authority, whistleblowing, conflicts of interest that affect the consultant, persistently poor communications in hospitals, systemic inequity in the availability or quality of services for some, and the standing of the consultant's recommendations, including their appearance in the patient's medical record.  相似文献   
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Joel Pust 《Synthese》1996,108(1):89-104
Hilary Kornblith (1993) has recently offered a reliabilist defense of the use of the Law of Small Numbers in inductive inference. In this paper I argue that Kornblith's defense of this inferential rule fails for a number of reasons. First, I argue that the sort of inferences that Kornblith seeks to justify are not really inductive inferences based on small samples. Instead, they are knowledge-based deductive inferences. Second, I address Kornblith's attempt to find support in the work of Dorrit Billman and I try to show that close attention to the workings of her computational model reveals that it does not support Kornblith's argument. While the knowledge required to ground the inferences in question is perhaps inductively derived, Billman's work does not support the notion that small samples provide a reliable basis for our generalizing inferences.  相似文献   
247.
We extended research on the role of noncontingent positive reinforcement following a functional analysis of attention-maintained self-injurious behavior to self-injury maintained by negative reinforcement in 2 young males with developmental disabilities. During a pretreatment functional analysis, each participant's self-injury was shown to be differentially sensitive to escape from instructional activities as negative reinforcement. During noncontingent escape, escape from learning activities was provided on a fixed-time schedule that was not influenced by the participant's behavior. One participant was also exposed to differential negative reinforcement of other behavior. During this condition, escape from instructional activities was provided contingent on the omission of self-injury for prespecified intervals. Results showed that the provision of escape, even when noncontingent, resulted in significant reductions in self-injury. These results are particularly interesting in light of the experimental history of noncontingent reinforcement as a control rather than as a therapeutic procedure. Noncontingent escape is discussed as a form of extinction that may be less likely than other forms of extinction to produce severe side effects.  相似文献   
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Noncontingent reinforcement (NCR) has emerged as a treatment package for severe behavior problems. Although concerns about potential side effects (such as incidental reinforcement) have been raised, there have been few reported negative side effects in published studies to date. In this article, we report an NCR treatment evaluation for severe aggression that produced (a) an extinction burst and (b) incidental reinforcement. These side effects were evaluated by examining within-session response patterns and response distributions. As a solution, a brief omission contingency was added to the reinforcement schedule. The omission contingency resulted in decreased aggression rates.  相似文献   
250.
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