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981.
Erich H. Loewy 《Theoretical medicine and bioethics》1996,17(1):61-74
This paper makes the assumption that organ transplantation is, under some conditions at least, a proper use of communal medical resources. Proceeding from this assumption, the author: (1) sketches the history of the problem; (2) briefly examines the prevalent models of communal structure and offers an alternate version; (3) discusses notions of justice and obligation derived from these different models; (4) applies these to the practice of harvesting organs for transplantation; and then (5) offers a different process for harvesting organs from the newly dead. If community is viewed as united by a set of shred goals and common values among which the value of community itself is important, then certain reciprocal obligations among members obtain. I suggest that routine salvage of organs from the newly dead be instituted but that it be routine salvage “with a twist”: rather early in life all members of the community are given the opportunity to refuse but their refusal carries the reciprocal condition that they cannot later become the recipients of that which they refuse to others. 相似文献
982.
Frank H. Durgin 《Attention, perception & psychophysics》1996,58(2):207-223
An aftereffect of perceived texture density contingent on the color of a surrounding region is reported. In a series of experiments, participants were adapted, with fixation, to stimuli in which the relative density of two achromatic texture regions was perfectly correlated with the color presented in a surrounding region. Following adaptation, the perceived relative density of the two regions was contingent on the color of the surrounding region or of the texture elements themselves. For example, if high density on the left was correlated with a blue surround during adaptation (and high density on the right with a yellow surround), then in order for the left and right textures to appear equal in the assessment phase, denser texture was required on the left in the presence of a blue surround (and denser texture on the right in the context of a yellow surround). Contingent aftereffects were found (1) with black-and-white scatter-dot textures, (2) with luminance-balanced textures, and (3) when the texture elements, rather than the surrounds, were colored during assessment. Effect size was decreased when the elements themselves were colored, but also when spatial subportions of the surround were used for the presentation of color. The effect may be mediated by retinal color spreading (Pöppel, 1986) and appears consistent with a local associative account of contingent aftereffects, such as Barlow’s (1990) model of modifiable inhibition. 相似文献
983.
Fetal brain tissue from the occipital or the frontal cortex was implanted into the damaged occipital cortex of adult rats. The animals receiving grafts of embryonic frontal cortex showed partial restoration of brightness discrimination while recipients given homologous implants of occipital cortex were as impaired as those animals with lesions alone. Neither frontal nor occipital grafts aided in the performance of a pattern discrimination problem; both groups of brain-damaged animals were unable to learn the task. Nonetheless, both groups of animals had viable and enlarged grafts with similar neuronal and glial profiles. 相似文献
984.
985.
Sara M. Freedman James S. Phillips 《Organizational behavior and human decision processes》1985,35(3):397-416
Situational performance constraints, task interest, and pay contingencies were manipulated in a laboratory study in order to investigate the cognitive mechanisms associated with the previously observed detrimental effects of constraints on affective task reactions. It was hypothesized that feelings of task competence and self-determination would account for both the direct and the interactive effects of constraints on motivation and satisfaction. The results of the study indicated that despite the fact that participants' performance was being constrained and they were aware of these constraints, the mere presence of the constraints alone failed to result in lower levels of satisfaction or motivation on a proofreading task. Post hoc analyses suggested that the constraints, in fact, led to negative affective task reactions when they also reduced participants' feelings of competence and self-determination. Interestingly, participants' generalized locus of control was associated with such effects. Internals tended to maintain stronger feelings of competence and self-determination than externals in the presence of constraints, thereby also maintaining greater motivation and satisfaction. 相似文献
986.
Brian H. Spitzberg William R. Cupach 《Journal of psychopathology and behavioral assessment》1985,7(3):207-220
The present study attempted to identify behavioral skills associated with global perceptions of communication competence and to determine if the relationship between competence and skills varies as a function of perceptual locus. Fifteen dyadic conversations were videotaped. Each interactant rated self and partner and was rated by four observers who viewed each tape. Results indicated that subjects' perceptions of their partners' skills accounted for 87% of the variance in subjects' ratings of partners' competence and 80% of the variance in subjects'self-perceived confirmation. Observers' ratings of subjects' skills predicted 83% of the variance in observers' ratings of subjects' competence. Observers'ratings of subjects'skills were unrelated to subjects' self-rated competence. 相似文献
987.
Gerald H. Zuk 《Contemporary Family Therapy》1985,7(1):3-10
The truncated nuclear family is defined: it is the garden-variety family pathology found. The critical role of polarized continuity and discontinuity values in producing the truncated nuclear family is discussed. There is a brief review of factors in American society which, over the decades since the Second World War, have evolved the nuclear family as a dominant family unit, and of how those and other factors in society have produced the large numbers of truncated nuclear families seen in clinics, particularly in the past decade. Family therapy is the treatment of choice for the truncated nuclear family, provided there is a readiness of the family to undertake the stress of therapy.Dr. Zuk is family therapy consultant to agencies in New Orleans and elsewhere, and clinical professor (psychology) in the Department of Psychiatry and Neurology at Tulane University Medical School.This paper is a chapter in the forthcoming 2nd edition ofProcess and Practice in Family Therapy, to be published by Human Sciences Press of New York City in 1985. 相似文献
988.
A. H. Thompson 《Personality and individual differences》1985,6(6):775-778
Considering the findings that schizophrenics have been found to show relatively slow reaction times (RTs), and often do not benefit from ordinarily helpful information (e.g. a warning signal), the present study investigated the relationship between these variables and psychoticism (P). One hundred and three male Ss were administered a questionnaire which provides a measure of P. In addition, all Ss were tested on an RT task under unsignalled (i.e. no warning signal) and signalled conditions. The results showed that the expected improvement in reaction speed with a warning signal was of a lesser magnitude for those high on P. Furthermore, the difference was due to the faster RTs for high P scorers in the unsignalled condition. The data suggest that high P scorers are like schizophrenics in that they show less benefit from a warning signal, but are dissimilar in terms of reaction speed in an unsignalled task. 相似文献
989.
990.
Timothy H. Monk Jeffrey E. Fookson Jacob Kream Margaret L. Moline Charles P. Pollak Muriel B. Weitzman 《Behavior research methods》1985,17(1):19-26
Cornell University Medical College, Westchester Division, The New York Hospital, White Plains, New York It is well established that there is a complex timekeeping mechanism in the human brain. This mechanism is associated with a variety of physiological and psychological rhythms having a period of about a day, and thus referred to as circadian rhythms. The circadian system has recently been modeled in terms of two underlying oscillators, one much more resistant to changes in routine than the other. These oscillators are considered to be endogenous, that is, internal to the organism, and not reliant for their existence upon changes in the person’s environment or general behavior. They thus continue to run even when the sleep/wake cycle is suspended, as in sustained operations. Thus, by their very nature, sustained operations require the individual to override the inputs that are coming from his or her circadian system (especially the indication that sleep is required). The aim of this paper is to provide a background to the area of circadian rhythms research, including a section on the methodology, so that the impact of the circadian system on sustained operations can be better understood. 相似文献