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171.
The supply of organs for transplant remains inadequate to meet the needs of waiting patients, in spite of many programs and approaches to increase rates of donation. Over the years there have been numerous proposals to introduce schemes that would move toward the outright sale of organs. Three articles in this issue of the Journal propose methods for increasing organ supply--two by moving toward a market approach and the third by advocating a change in social culture. All three suffer from shortcomings, including the endorsement and encouragement of the exploitation of those who may offer organs. Although the shortage of organs must be addressed, the social price of a market in organs is too high, and proposals to encourage a rethinking of social responsibility are unlikely to be effective.  相似文献   
172.
173.
Social identity theory (SIT) proposes that the more strongly individuals identify with their group, the less favorable attitudes they hold toward dissimilar groups. In contrast, multicultural theory proposes that affirmation toward one's group--particularly with respect to ethnicity--should correspond with higher levels of acceptance toward dissimilar groups. These competing theories were examined with 486 non-Hispanic White, African American, and Hispanic/Latino university students to determine if support would be found for either theory. Consistent with SIT, levels of ethnic identity correlated significantly with levels of ethnocentrism for Whites and Hispanics but not for African Americans. African Americans obtained significantly higher ethnic identity and self-esteem scores than the other 2 groups. Implications of the findings are discussed.  相似文献   
174.
Editorial     

Editorial Commentary

Editorial  相似文献   
175.
In contrast to prospective power analysis, retrospective power analysis provides an estimate of the statistical power of a hypothesis test after an investigation has been conducted rather than before. In this article, three approaches to obtaining point estimates of power and an interval estimation algorithm are delineated. Previous research on the bias and sampling error of these estimates is briefly reviewed. Finally, an SAS macro that calculates the point and interval estimates is described. The macro was developed to estimate the power of anF test (obtained from analysis of variance, multiple regression analysis, or any of several multivariate analyses), but it may be easily adapted for use with other statistics, such as chi-square tests ort tests.  相似文献   
176.
The aim of this study was to identify reliable and valid subgroups of spinal pain patients, using data from the Swedish version of the Multidimensional Pain Inventory (MPI-S). A second aim was to test the generalisability of the three patient profiles described in earlier studies on the MPI ("adaptive coper", "dysfunctional" and "interpersonally distressed" patients). The study base consisted of two samples of individuals suffering from long-term, non-specific spinal pain and the results were validated across these samples. Cluster analysis was used to detect distinct groups of patients and the validity of these subgroups was evaluated on variables not used to generate the cluster solution. One subgroup was characterised by lower pain severity, lower interference with everyday activities, lower affective distress and higher life control than the other two subgroups. This patient profile was similar to the MPI adaptive coper patients. A second subgroup resembled the dysfunctional patient profile, thus displaying a worse adjustment to chronic pain than the AC patients. The third patient group reported significantly lower levels of social support from "significant others" than the other subgroups. This patient profile was similar to that of the interpersonally distressed patient group. Taken together, the results support the reliability, validity and generalisability of three subgroups of chronic pain patients derived from the MPI-S.  相似文献   
177.
Developmental changes in the kinematics and kinetics underlying balance control were studied in 61 children, 9 months to 10 years of age. The children were classified according to developmental milestones as standers; new, intermediate, and advanced walkers; runners-jumpers; hoppers; gallopers; and skippers. The children experienced support-surface translations of varying size and speed. Children with greater locomotor experience withstood larger balance threats without collapsing or stepping. Analyses of scaled trials (perturbations normalized in size to foot length and center of gravity height) revealed that improvement in balance was not related to initial configuration parameters surrounding the task (degree of crouch or lean). Children with advanced locomotor skills had faster recovery times and relatively larger muscle torques than children with less experience. Relative torque-time histories of the more experienced children began to match the adult response to similar perturbations. With increased experience and changing muscle torque regulatory abilities, balance skills became more robust.  相似文献   
178.
The relationship between suicide and birthdays, and suicide and public holidays has been studied from data on 32,291 Danish suicides by persons ages 15 years and older in the 25-year period 1970-1994. Evidence was found to support the theory of the "broken-promise effect" for major public holidays in that there appears to be a postponement of a significant number of suicides from before a holiday until after. The division of holidays into nonworking and (half-time) working days showed that a "holiday effect" could only be found around major public holidays, particularly Christmas, Easter, and Whitsun. The postponing or transpositioning effect is relevant to prevention, especially because of the availability and accessibility of help at the end of and after major public (nonworking) holidays.  相似文献   
179.
It is generally assumed that syntax is represented linguistically rather than conceptually, consistent with the more general view that language and thought are coded separately. This claim is widely defended on logical grounds, but it has received little experimental support. In the present study, we asked Spanish and English speakers to make semantic and syntactic categorizations for pictures and their corresponding names. Consistent with past results, latencies to semantically categorize pictures and words were similar. The new finding is that participants were faster to make syntactic decisions for words compared with pictures, suggesting that syntactic features such as grammatical gender and the count-mass distinction are more closely linked to lexical than conceptual representations.  相似文献   
180.
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