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Patricia A. Marshall David C. Thomasma Abdallah S. Daar 《Theoretical medicine and bioethics》1996,17(1):1-18
The severe shortage of organs for transplantation and the continual reluctance of the public to voluntarily donate has prompted consideration of alternative strategies for organ procurement. This paper explores the development of market approaches for procuring human organs for transplantation and considers the social and moral implications of organ donation as both a “gift of life” and a “commodity exchange.” The problematic and paradoxical articulation of individual autonomy in relation to property rights and marketing human body parts is addressed. We argue that beliefs about proprietorship over human body parts and the capacity to provide consent for organ donation are culturally constructed. We contend that the political and economic framework of biomedicine, in western and non-western nations, influences access to transplantation technology and shapes the form and development of specific market approaches. Finally, we suggest that marketing approaches for organ procurement are and will be negotiated within cultural parameters constrained by several factors: beliefs about the physical body and personhood, religious traditions, economic conditions, and the availability of technological resources. 相似文献
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Patricia MacCorquodale Susan A. Basow Mary Anne Fitzpatrick Deborah Kuhn-McGregor 《Sex roles》1985,13(9-10):567-579
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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
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Nondepressed human subjects were divided into seven groups. On a series of discrimination problems, a helplessness group received insoluble problems, a solvable group received contingent feedback, and a no treatment control group received no feedback. For two other groups insoluble problems were preceded by success feedback on a different task presented according to a fixed ratio (FR) or variable ratio (VR) schedule of reinforcement. Two control groups received either FR or VR schedules of success but were not examined on the discrimination problems. All groups were tested for escape/avoidance performance on a human shuttle box. Both FR and VR schedules produced an inoculation against learned helplessness; escape performance by the helplessness group was significantly worse than that of FR and VR inoculation groups. These latter groups performed similar to the solvable and three control groups. Significantly worse than that of FR and VR inoculation groups. These latter groups performed similar to the solvable and three control groups. Significantly fewer subjects in the VR inoculation group exhibited avoidance responses than their counterparts in the FR inoculation group. despite similar escape performance. The findings indicate that learned helplessness can be prevented in humans and suggest different sources of interference produced by unpredictable and uncontrollable events. 相似文献
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Mary L. Fennell Patricia R. Barchas Elizabeth G. Cohen Anne M. McMahon Polly Hildebrand 《Sex roles》1978,4(4):589-604
This article takes a sociological approach to a problem that has usually been considered as a psychological phenomenon. It addresses the problem of male—female interactions in work situations utilizing the organizational concepts of division of labor and legitimacy. Traditional explanations evoking sex-role socialization are reviewed and rejected for purposes of experimentation and intervention. An alternative argument, focusing on the structural arrangements of organizational settings, is presented as an explanation for behavioral effects previously attributed to inherent sex differences. The results of a pilot study are briefly described, and directions for further experimentation and possible intervention strategies are suggested.The bibliographic search and initial conceptualization of this research was supported by a grant from the Ford Foundation under the auspices of the Center for Research on Women at Stanford University. We are grateful to Miriam Rosen for much of the bibliographic work. The pilot study was supported in part by funds from the Guggenheim Foundation and by a grant from the Spencer Foundation. We also wish to thank Richard Torres and Christie Timberlake for their invaluable assistance on this project. 相似文献
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Mental rotation in the congenitally blind was investigated with a haptic letter-judgment task. Blind subjects and blindfolded, sighted subjects were presented a letter in some orientation between 0° to 300° from upright and timed while they judged whether it was a normal or mirror-image letter. Both groups showed an increasing response time with the stimulus’s departure from upright; this result was interpreted as reflecting the process of mental rotation. The results for the blind subjects suggest that mental rotation can operate on a spatial representation that does not have any specifically visual components. Further research showed that for the sighted subjects in the haptic task, the orientation of a letter is coded with respect to the position of the hand. Sighted subjects may code the orientation of the letter and then translate this code into a visual representation, or they may use a spatial representation that is not specifically visual. 相似文献