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51.
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A tone ending with electrical shock was periodically presented to pigeons while they pecked a key for food. Pairs of birds were run simultaneously under a yoked program which insured that both birds received the same number and temporal distribution of shocks. For one of the birds, shock was always initiated by a peck; for the other, shock was unavoidable. Both procedures led to reduced rates of pecking in the presence of the tone, and gradients of stimulus generalization were obtained. But the effects of response contingent shock extinguished more rapidly than the effects of unavoidable shock. In general, birds exposed to unavoidable shock tended to respond at intermediate rates throughout tone, whereas those exposed to response contingent shock ceased to peck for part or all of the tone period.  相似文献   
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This study reports the results of three field experiments which demonstrate that asking someone how they feel, having them verbally respond, and then acknowledging that response, facilitates compliance with a charitable request. The findings are discussed with respect to the influence of public commitments on behavioral consistency.
Before you ask anyone for a donation, you first ask them how they're feeling. After they tell you they're feeling good, and you tell them you're glad they're feeling good, the/11 be more likely to contribute to helping someone who isn't.  相似文献   
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Risk perceptions and participation in colorectal cancer screening   总被引:4,自引:0,他引:4  
Compared individuals at high versus average risk for colorectal cancer (CRC) with respect to factors they cited as affecting their risk of developing CRC. We also examined the relationship of these risk-factor perceptions to perceived susceptibility and participation in a CRC screening test. All individuals in the high-risk group were informed that, as a sibling of someone with CRC, they were more likely to get this cancer themselves. We found minimal differences among siblings with respect to perceived susceptibility. Further, although high-risk siblings were more likely to participate in screening, only 20.2% cited heredity as a risk-increasing factor, and, among these siblings, there was no relationship between screening participation and the citation of any specific risk factors, including heredity. These findings demonstrate the need for more research examining how high-risk individuals process risk-relevant information and the effect of this information on health behavior.  相似文献   
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Several cases encountered in psychiatric practice are described in which herpetic involvement of the trigeminal nerve appeared to be crucial to the pathophysiology of the patients’s illness. A brief history of herpes is discussed in terms of the anatomy and physiology of the trigeminal nerve. Particular attention is given to the effects of intraneuronal herpes on gasserian ganglion and spinal nuclei discharge threshoolds, as well as viral pathways directly impacting the substantia nigra. Evidence characterizing Parkinson’s disease as one of several important manifestations of CNS herpes is covered. This article will be presented, by invitation, at the Neuroscience Seminar, Department of Medicine, University of Otago, Dunedin, New Zealand, on 19 August 1997.  相似文献   
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A theory of right action is implicit in Hume's delineation of the virtues. It gives qualified priority to 'rules of justice' as Hume's remarks on 'that species of utility which attends this virtue' require. It is a useful actual-rule, not an ideal possible-rule, purely utilitarian theory that discounts rules of justice in 'extraordinary cases', has a problem when rules conflict, and invites the question 'Why not hark directly to the supreme law of utility in every case?'. It does not reflect contractarian considerations of mutuality of interests evident in Hume's texts, which while sometimes relevant to what is reasonable, are in his view never also relevant to what is moral.  相似文献   
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The treatment of life-threatening illnesses in childhood is replete with ethical issues and with clinical issues that have ethical implications. The central issues are those involved with a child's participation in the decision-making process and with communication of information about the illness and treatments to children. This article examines the questions of patient autonomy and of parental responsibility and prerogative in the context of pediatric oncology. Included in this examination of the ethical dimensions of pediatric life-threatening illness is a discussion of the many related aspects involved, including medical, cultural, psychosocial, legal, and developmental. A multidimensional approach that considers the ways in which these multiple aspects interact with one another, and which focuses on establishing a strong working alliance between the health care team and the pediatric patient's family, can help to avoid or resolve potential ethical and clinical conflicts.  相似文献   
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