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251.
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Previous research suggests that the Relational Completion Procedure may be an effective alternative procedure for studying derived relational responding. However, the parameters that make it effective, relative to traditional match-to-sample, remain to be determined. The present experiment compared the Relational Completion Procedure and match-to-sample protocols for training and testing Same and Opposite derived stimulus relations. Trials to criterion and overall pass rate (i.e., yield) in both procedures were compared across three variables: presence versus absence of a confirmatory response requirement, three versus five comparison stimuli, and top-to-bottom versus left-to-right presentation format. Findings demonstrated a facilitative effect of the confirmatory response requirement in both procedures. Training trials to criterion were nominally but not significantly lower during the nonarbitrary training phase in the Relational Completion Procedure compared to match-to-sample, and the overall yield on the arbitrary relational test was greater in the former procedure compared to the latter. The present findings support the further development of the Relational Completion Procedure as an efficient alternative procedure for establishing Same and Opposite relations with adult humans, and with potential applicability to other types of derived relations.  相似文献   
253.
Objective: In an earlier study, improvement of dietary status with food supplements led to a reduction in antisocial behavior among prisoners. Based on these earlier findings, a study of the effects of food supplements on aggression, rule‐breaking, and psychopathology was conducted among young Dutch prisoners. Methods: Two hundred and twenty‐one young adult prisoners (mean age=21.0, range 18–25 years) received nutritional supplements containing vitamins, minerals, and essential fatty acids or placebos, over a period of 1–3 months. Results: As in the earlier (British) study, reported incidents were significantly reduced (P=.017, one‐tailed) in the active condition (n=115), as compared with placebo (n=106). Other assessments, however, revealed no significant reductions in aggressiveness or psychiatric symptoms. Conclusion: As the incidents reported concerned aggressive and rule‐breaking behavior as observed by the prison staff, the results are considered to be promising. However, as no significant improvements were found in a number of other (self‐reported) outcome measures, the results should be interpreted with caution. Aggr. Behav. 36:117–126, 2010. © 2009 Wiley‐Liss, Inc.  相似文献   
254.
肿瘤干细胞理论认为,肿瘤增长是由肿瘤中具有干细胞特性的细胞分裂增殖引起的。针对性地抑制肿瘤干细胞的增殖,能显著提高肿瘤治愈率。本文用哲学的观点对肿瘤干细胞假说的提出、验证、临床应用进行分析,对于深入认识肿瘤干细胞的本质、探索其分离方法、发现抑制其增殖的有效手段将起到积极作用。  相似文献   
255.
人类胚胎干细胞的来源与伦理思考   总被引:8,自引:2,他引:8  
人类胚胎干细胞研究的伦理问题较多,因此要思考胚胎干细胞的伦理问题。胚胎干细胞来源有四种:选择性流产的人类胚胎组织;治疗不孕症夫妇不需要的由体外受精产生的人类胚胎;由捐献者专门为研究所捐献的配子由体外受精产生的人类胚胎;由体细胞核移植技术将人体细胞核移植入人或动物的卵泡内产生人类胚胎或嵌合体胚胎。用不同胚胎来源研究干细胞产生的伦理问题不同,伦理的思考和结论也不同。  相似文献   
256.
Marriage, once a gateway to adulthood, is no longer as widely considered a requirement for achieving adult status. With declining marriage rates and delayed marital transitions, some have wondered whether current young adults have rejected the traditional notion of marriage. Utilizing a sample of 571 young adults, the present study explored how marital centrality (the expected importance to be placed on the marital role relative to other adult roles) functioned as a unique and previously unexplored marital belief among young adults. Results suggested that marriage remains an important role for many young adults. On average, young adults expected that marriage would be more important to their life than parenting, careers, or leisure activities. Marital centrality profiles were found to significantly differ based on both gender and religiosity. Marital centrality was also associated with various outcomes including binge-drinking and sexual activity. Specifically, the more central marriage was expected to be, the less young adults engaged in risk-taking or sexual behaviors.  相似文献   
257.
258.
Adult attachment has been studied as an important predictor of romantic relationship quality in many empirical studies. This meta‐analysis quantitatively summarized the associations between the two insecure adult attachment dimensions, anxiety and avoidance, and cognitive, emotional, and behavioral indicators of romantic relationship quality based on 73 previous studies with 118 independent samples of 21 602 individuals. More importantly, we examined the different effects of anxiety and avoidance on relationship quality. We also tested the potential moderating effects of gender on the strength of these associations. Meta‐analytic results confirmed that both anxiety and avoidance were detrimental to the cognitive, emotional, and behavioral aspects of relationship quality. Compared with anxiety, avoidance was more negatively associated with general satisfaction, connectedness, and general support in relationships. In contrast, anxiety was more positively associated with general conflict in relationships. The moderating effect of gender was weak. However, supplementary analyses found that the type of couple interaction measures (self‐report versus observation) significantly moderated the relations between insecure attachments and the behavioral indicators of relationship quality. Our results integrate and extend previous findings about the dynamics of adult attachment and romantic relationship quality. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
259.

神经嵌合体研究具有潜在重要的科研与社会价值,也引起了诸多伦理关注。聚焦于将人类神经组织、细胞或基因在非人动物中表达所引发的伦理问题:通过比较国际干细胞研究学会新旧指南关于嵌合体的定义,指出不同胚起源、“基因上不同”起源的嵌合体界定存在的问题,以及这些界定对伦理讨论的启示;结合科研进展探讨了受试动物福祉、道德地位变化等问题,以试图厘清人们对这类研究的关键忧虑;并在科学必要性与规范合理性的视角下提出针对性的治理建议。

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260.
This study considers links between the number of types of violence to which women have been exposed, depression, and executive functions (EFs). Substantial research has established EF deficits among depressed individuals as well as individuals exposed to trauma. Studies have also indicated a relationship between trauma exposure and depressive symptoms across a range of traumatic events, such as combat exposure, motor vehicle accidents, natural disasters, and assaults. This study examines this relationship in an ethnically diverse community sample of 93 women exposed to interpersonal violence who completed a battery of EF tasks that assessed processing speed, working memory, response inhibition, and set shifting. Women reported an average of 5.8 types of interpersonal violence events. The number of types of interpersonal violence events was significantly related to depressive symptoms, although not EF performance. Specific EFs, such as working memory and response inhibition, were positively related to depressive symptoms.  相似文献   
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