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In this paper a case is used to demonstrate how ethical analysis enables health care professionals, patients and family members to make treatment decisions which ensure that medical technologies are used in the overall best interests of the patient. The claim is made and defended that ethical analysis can secure four beneficial outcomes when medical technologies are employed: (1) not allowing any medical technologies to be employed until the appropriate decision makers are identified and consulted; (2) insisting that medical technologies be employed not merely to promote the medical interests of the patient but rather on the basis of their ability to contribute to the overall well-being of the patient; (3) challenging caregivers to reflect on the dynamic interplay between their conscious and unconscious values and consequent determinations of what is in the patient's best interests; and (4) providing a justification for selected interventions which makes possible rational dialogue between caregivers espousing different viewpoints about treatment options.  相似文献   
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An operant simulation of foraging through baited and empty patches was studied with 4 pigeons. On a three-key panel, side keys were designated as patches, and successive opportunities to complete 16 fixed-ratio 10 schedules on side keys were defined as encounters with feeders. In a random half of the patches in any session, some of the fixed-ratio 10 schedules yielded reinforcement (baited feeders) and the other schedules yielded nonreinforcement (empty feeders). In the other half of the patches, all feeders were empty. Pigeons could travel between patches at any time by completing a fixed-ratio schedule on the center key. An optimal foraging model was tested in Experiments 1 and 2 by varying center-key travel time and number of baited feeders in baited patches. The ordinal predictions that number of feeders visited in empty patches would increase with travel time and decrease as number of baited feeders increased were supported, but pigeons visited far more feeders in empty patches than the optimal number predicted by the model to maximize energy/time. In Experiment 3, evidence was found to suggest that the number of empty feeders encountered before the first baited feeder in baited patches is an important factor controlling leaving empty patches.  相似文献   
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Thirty-eight male college students, classified as either Type A or Type B based on their Jenkins Activity Survey (JAS-T) scores, competed in a reaction time task that allowed them to administer shocks to an increasingly provocative fictitious opponent. Salivary testosterone and cortisol were measured both prior to and after the task. Aggression was defined as the level of shock the subject was willing to set for the opponent. The results of this study indicate that a relationship exists between endogenous testosterone levels in men and direct physical aggression. Some evidence for the moderating effects of hormones on the level of aggression expressed by Type As was observed. No direct relationship between Type A and aggression was found.  相似文献   
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This study analysed the way 20 managers in the information technology industry in Australia viewed their lives, and identified two dimensions of central importance cutting across the work, family and leisure spheres encompassed by them. One dimension was positively loaded towards activities which were challenging, creative and under the individual's control. These activities were enjoyable, and included examples such as consulting with clients, creating new business, and communicating and dealing with others, whether at work or at home. The opposite pole of this dimension involved activities such as completing paperwork, general administration, doing the shopping, and disciplining the children. Such activities were seen as necessary, routine or stressful, and were generally disliked. The other dimension dealt with activities which, at one pole, were emotionally involving or involved moral standards, and included examples such as attending meetings, doing things as a family, and settling disputes, either at work or at home. At the other pole were activities which were usually done alone and involved no sense of social or moral obligation. Leisure activities typically fell into this category. The results indicated that these managers generally pursued a lifestyle which was seen to be non-stressful, and one valued for the challenge, enjoyment, freedom of choice and personal control which it offered.  相似文献   
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Victims' perceptions of social support: what is helpful from whom?   总被引:5,自引:0,他引:5  
Although research has demonstrated that social interactions influence psychological well-being, little is known about what specific actions victims of stressful life events experience as helpful or unhelpful. Wortman and Dunkel-Schetter (1979) previously suggested that victims frequently experience rejection, withdrawal, and communication problems with those close to them. To address these issues, 55 cancer patients were interviewed concerning the specific actions they found to be helpful or unhelpful from several potential support providers: spouse, other family members, friends, acquaintances, others with cancer, physicians, and nurses. The data indicated that the Wortman and Dunkel-Schetter victimization model applied better to interactions with friends and acquaintances than to interactions with close family members. In addition, support was found to be partially dependent on the source: Particular actions were perceived to be helpful from some but not other network members. Implications for theory and research on social support are discussed.  相似文献   
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On the basis of a conditioning analysis of the orientation-contingent color aftereffect (McCollough effect, ME), orientation stimuli become associated with simultaneously presented chromatic stimuli. This account suggests that decreasing the contingency between the grid orientation and color should decrease the strength of the aftereffect. Results of previous research indicate that decreasing the temporal contingency (by presenting homogeneous chromatic stimuli between presentations of chromatic grids) does not decrease the ME. However, it has been suggested that the appropriate contingency-degradation procedure would involve decreasing spatial (rather than temporal) contingency. That is, the illusion should be attenuated by extending the color beyond the confines of the grid. Contrary to this hypothesis, the results of the present experiments provide no evidence that decreasing the spatial contingency between grid and color decreases the ME; rather, the aftereffect is increased by such a manipulation.  相似文献   
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The concurrent validity of the motor domain from the Vineland Adaptive Behavior Scales was estimated using scores from the Peabody Developmental Motor Scales as criteria. A moderately high correlation between the measures was obtained. Implications, particularly for preschool children, were discussed.  相似文献   
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