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181.
Until the advent of plastinated cadavers, few outside the medical professions have had firsthand experience with human corpses. Such opportunities are now available at the Body Worlds exhibits of Gunther von Hagens. After an overview of these exhibits, we explore visitor responses as revealed in comment books available upon exiting the exhibit. Cultural, philosophical, and religious issues raised in the comments serve as a microcosm of society at large. The conclusion considers the challenge of such exhibits in introducing the public to science education, notes the image of the body as machine-so prevalent in the West-reflected in visitor comments, and finds hope that the exhibits promote, for many visitors, a sense of community among all humankind.  相似文献   
182.
The self-reporting of cancer history is becoming increasingly important, as it frequently guides medical decision-making. We studied the accuracy of personal cancer history using a self-administered questionnaire, comparing the results with the Tumor Registry at our institution. Among 39,662 records, we identified 3614 women with a single cancer in the Tumor Registry who reported none or one cancer on their questionnaire. The sensitivity in self-reporting cancers was 85.7%, ranging from 92.1% for breast cancer to 42.9% for leukemia. The accuracy for breast cancer and Hodgkin's Lymphoma was significantly better than other cancers (p=0.00027, CI: 1.4–3.88). Analysis of patient's characteristics showed that Caucasians reported breast cancer more accurately than Asian/Pacific Islanders (p=0.008), and those with Jewish ancestry more accurately than non-Jewish (p=0.0435). These results will help us to improve data collection and thus improve medical decision-making.  相似文献   
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Three experiments using human participants varied the distribution of point‐gain reinforcers or point‐loss punishers in two‐alternative signal‐detection procedures. Experiment 1 varied the distribution of point‐gain reinforcers for correct responses (Group A) and point‐loss punishers for errors (Group B) across conditions. Response bias varied systematically as a function of the relative reinforcer or punisher frequencies. Experiment 2 arranged two conditions — one where an unequal ratio of reinforcement (5:1 or 1:5) was presented without punishment (R‐only), and another where the same reinforcer ratio was presented with an equal distribution of point‐loss punishers (R+P). Response bias was significantly greater in the R‐only condition than the R+P condition, supporting a subtractive model of punishment. Experiment 3 varied the distribution of point‐gain reinforcers for correct responses across four unequal reinforcer ratios (5:1, 2:1, 1:2, 1:5) both without (R‐only) and with (R+P) an equal distribution of point‐loss punishers for errors. Response bias varied systematically with changes in relative reinforcer frequency for both R‐only and R+P conditions, with 5 out of 8 participants showing increases in sensitivity estimates from R‐only to R+P conditions. Overall, the results indicated that punishers have similar but opposite effects to reinforcers in detection procedures and that combined reinforcer and punisher effects might be better modeled by a subtractive punishment model than an additive punishment model, consistent with research using concurrent‐schedule choice procedures.  相似文献   
185.
This study investigated the link between meditation, self-reported mindfulness and cognitive flexibility as well as other attentional functions. It compared a group of meditators experienced in mindfulness meditation with a meditation-naïve control group on measures of Stroop interference and the “d2-concentration and endurance test”. Overall the results suggest that attentional performance and cognitive flexibility are positively related to meditation practice and levels of mindfulness. Meditators performed significantly better than non-meditators on all measures of attention. Furthermore, self-reported mindfulness was higher in meditators than non-meditators and correlations with all attention measures were of moderate to high strength. This pattern of results suggests that mindfulness is intimately linked to improvements of attentional functions and cognitive flexibility. The relevance of these findings for mental balance and well-being are discussed.  相似文献   
186.
We investigate the processes underlying the feeling of control over one’s actions (“sense of agency”). Sense of agency may depend on internal motoric signals, and general inferences about external events. We used priming to modulate the sense of agency for voluntary and involuntary movements, by modifying the content of conscious thought prior to moving. Trials began with the presentation of one of two supraliminal primes, which corresponded to the effect of a voluntary action participants subsequently made. The perceived interval between movement and effect was used as an implicit measure of sense of agency. Primes modulated perceived intervals for both voluntary and involuntary movements, but the modulation was greatest for involuntary movements. A second experiment showed that this modulation depended on prime–movement (temporal) contiguity. We propose that sense of agency is based on a combination of internal motoric signals and external sensory evidence about the source of actions and effects.  相似文献   
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United States federal regulations for pediatric research with no prospect of direct benefit restrict institutional review board (IRB) approval to procedures presenting: 1) no more than "minimal risk" ( section sign 45CFR46.404); or 2) no more than a "minor increase over minimal risk" if the research is commensurate with the subjects' previous or expected experiences and intended to gain vitally important information about the child's disorder or condition ( section sign 45CFR46.406) (DHHS 2001). During the 25 years since their adoption, these regulations have helped IRBs balance subject protections with the pursuit of scientific knowledge to advance children's welfare. At the same time, inconsistency in IRB application of these regulations to pediatric protocols has been widespread, in part because of the ambiguity of the regulatory language. During the past decade, three federally-charged committees have addressed these ambiguities: 1) the National Human Research Protections Advisory Committee (NHRPAC) (Washington, DC), 2) the Institute of Medicine (IOM) Committee on the Ethical Conduct of Clinical Research Involving Children (Washington, DC); and 3) the United States Department of Health and Human Services Secretary's Advisory Committee for Human Research Protections (SACHRP) (Washington, DC). The committees have reached similar conclusions on interpretation of language within regulations section sign section sign 45CFR46.404 and 406; these conclusions are remarkably consistent with recent international recommendations and those of the original National Commission for the Protection of Human Subjects of Biomedical and Behavioral Research (1977) report from which current regulations are based. Drawing on the committees' public reports, this article identifies the ethical issues posed by ambiguities in regulatory language, summarizes the committees' deliberations, and calls for a national consensus on recommended criteria.  相似文献   
189.
Prior research often emphasized a stimulus‐based or bottom‐up view of product category representations. In contrast, we emphasize a more purposeful, top‐down perspective and examine categories that consumers might construct in the service of salient (i.e., highly accessible) goals. Specifically, we investigate how the point of view imposed by salient consumer goals might affect category representations assessed by participants’ similarity judgments of food products. A key factor in our study is that we examine both individual and situational sources of variability in goal salience. In addition, we also vary the surface‐level, visual resemblance of the stimulus pairs of foods used in the study. The results suggest that personal goals (e.g., health) and situational goals (e.g., convenience) act in conjunction and exert a systematic impact on category representations. Both types of goals, when salient, enhanced the perceived similarity of goal‐appropriate products and reduced the similarity of product pairs when only one product was ideal for the particular goal. The similarity‐enhancing effect was most pronounced when the surface resemblance between the products was low, and the similarity‐diminishing effect was more apparent when surface resemblance was high. Implications are discussed for current theoretical assumptions regarding categorization in consumer research.  相似文献   
190.
Maternal psychopathology has long been recognized as a risk factor for psychopathology in offspring; however, some resilient youth achieve a favorable outcome in the presence of maternal psychopathology. We identified factors that predicted resilience among youth who were exposed to adverse life events, and also examined whether the same factors protected youth against maternal psychopathology and adverse life events. Main and interaction effects of child and family factors were examined employing cross-sectional data from a household probability sample of 1285 youth aged 9 through 17 collected at four sites. On average, children exhibited a greater degree of resilience when they had higher IQ, closer parental monitoring, better family functioning, higher educational aspiration, and were female. Interaction between maternal psychopathology and IQ was significant, and there was a trend between maternal psychopathology and gender. A higher IQ is a protective factor against both maternal psychopathology and adverse life events; whereas being a girl seems to be a protective factor against maternal psychopathology, but not adverse life events.  相似文献   
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