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111.
兴奋性氨基酸(EAAs) 广泛分布于中枢神经系统,参与多种生理过程包括学习、记忆和伤害感受等。然而,EAAs 受体的过度兴奋却可引发一系列细胞事件,最终导致神经元的损伤与死亡。许多神经退行性疾病如早老性痴呆、癫痫和肌侧索硬化症等都与EAAs 的兴奋毒作用有关。目前的研究表明,由EAAs 受体过度兴奋所引发的细胞内钙超载是导致神经元死亡的最终途径  相似文献   
112.
What are moral principles? In particular, what are moral principles of the sort that (if they exist) ground moral obligations or—at the very least—particular moral truths? I argue that we can fruitfully conceive of such principles as real, irreducibly dispositional properties of individual persons (agents and patients) that are responsible for and thereby explain the moral properties of (e.g.) agents and actions. Such moral dispositions (or moral powers) are apt to be the metaphysical grounds of moral obligations and of particular truths about what is morally permissible, impermissible, etc. Moreover, they can do other things that moral principles are supposed to do: explain the phenomena “falling within their scope,” support counterfactuals, and ground moral necessities, “necessary connections” between obligating reasons and obligations. And they are apt to be the truthmakers for moral laws, or “lawlike” moral generalizations.  相似文献   
113.
Prior research has shown that people can learn many nouns (i.e., word–object mappings) from a short series of ambiguous situations containing multiple words and objects. For successful cross‐situational learning, people must approximately track which words and referents co‐occur most frequently. This study investigates the effects of allowing some word‐referent pairs to appear more frequently than others, as is true in real‐world learning environments. Surprisingly, high‐frequency pairs are not always learned better, but can also boost learning of other pairs. Using a recent associative model (Kachergis, Yu, & Shiffrin, 2012), we explain how mixing pairs of different frequencies can bootstrap late learning of the low‐frequency pairs based on early learning of higher frequency pairs. We also manipulate contextual diversity, the number of pairs a given pair appears with across training, since it is naturalistically confounded with frequency. The associative model has competing familiarity and uncertainty biases, and their interaction is able to capture the individual and combined effects of frequency and contextual diversity on human learning. Two other recent word‐learning models do not account for the behavioral findings.  相似文献   
114.
余嘉元 《心理学报》1994,27(2):219-224
为探讨线性逻辑斯谛模型(LLTM)的拟合条件及其和解题策略同质性之间的关系,让被试比较两个负整数指数幂的大小,发现全体被试的数据不能与拉希模型及LLTM相拟合。把被试按其解题策略分成不同策略组后,同一策略组被试的数据可以拟合于拉希模型,但对于LLTM,同一策略组的数据中部分项目的拟合较好,另外一些项目的拟合较差。这一结果表明,解题策略的同质性是LLTM拟合的必要条件,但还不是充分条件。  相似文献   
115.
Why do people express moral outrage? While this sentiment often stems from a perceived violation of some moral principle, we test the counter-intuitive possibility that moral outrage at third-party transgressions is sometimes a means of reducing guilt over one’s own moral failings and restoring a moral identity. We tested this guilt-driven account of outrage in five studies examining outrage at corporate labor exploitation and environmental destruction. Study 1 showed that personal guilt uniquely predicted moral outrage at corporate harm-doing and support for retributive punishment. Ingroup (vs. outgroup) wrongdoing elicited outrage at corporations through increased guilt, while the opportunity to express outrage reduced guilt (Study 2) and restored perceived personal morality (Study 3). Study 4 tested whether effects were due merely to downward social comparison and Study 5 showed that guilt-driven outrage was attenuated by an affirmation of moral identity in an unrelated context.  相似文献   
116.
We examined associations between children’s peer relationships and (a) their parents’ social competence as well as (b) their parents’ behaviors during the children’s peer interactions. Participants were families of 124 children ages 6–10 (68% male), 62 with ADHD and 62 age- and sex-matched comparison youth. Children’s peer relationships were assessed via parent and teacher report, and sociometric nominations in a lab-based playgroup. Parental characteristics were assessed via parent self-report and observations of behavior during their child’s playgroup. After statistical control of relevant covariates, parents of children with ADHD reported poorer social skills of their own, arranged fewer playdates for their children, and displayed more criticism during their child’s peer interaction than did parents of comparison youth. Parents’ socialization with other parents and facilitation of the child’s peer interactions predicted their children having good peer relationships as reported by teachers and peers, whereas parental corrective feedback to the child and praise predicted poor peer relationships. Parents’ ratings of their child’s social skills were positively associated with ratings of their own social skills, but negatively associated with criticism and facilitation of the child’s peer interactions. Relationships between parental behaviors and peer relationships were stronger for youth with ADHD than for comparison youth. The relevance of findings to interventions is discussed.  相似文献   
117.
Parenting and family interventions have repeatedly shown effectiveness in preventing and treating a range of youth outcomes. Accordingly, investigators in this area have conducted a number of studies using statistical mediation to examine some of the potential mechanisms of action by which these interventions work. This review examined from a methodological perspective in what ways and how well the family-based intervention studies tested statistical mediation. A systematic search identified 73 published outcome studies that tested mediation for family-based interventions across a wide range of child and adolescent outcomes (i.e., externalizing, internalizing, and substance-abuse problems; high-risk sexual activity; and academic achievement), for putative mediators pertaining to positive and negative parenting, family functioning, youth beliefs and coping skills, and peer relationships. Taken as a whole, the studies used designs that adequately addressed temporal precedence. The majority of studies used the product of coefficients approach to mediation, which is preferred, and less limiting than the causal steps approach. Statistical significance testing did not always make use of the most recently developed approaches, which would better accommodate small sample sizes and more complex functions. Specific recommendations are offered for future mediation studies in this area with respect to full longitudinal design, mediation approach, significance testing method, documentation and reporting of statistics, testing of multiple mediators, and control for Type I error.  相似文献   
118.
Cardiomyopathy is a genetically and clinically heterogeneous, life threatening disease which affects people of all ages. Recent guidelines provide recommendations for cardiac screening and genetic testing in at-risk relatives, but the uptake and impact of these measures in the United States is unknown. This is a single institution retrospective study that characterizes the uptake of cardiac screening and genetic testing for relatives of a cohort of 57 probands with hypertrophic (HCM) and dilated cardiomyopathy (DCM) who underwent both clinical evaluation and genetic testing. Cardiac screening was indicated for 302 relatives. One hundred and seventy-three (57 %) completed cardiac screening. Forty of the 57 probands were mutation positive and genetic testing was indicated for 213 relatives. Eighty-four (39 %) completed genetic testing. The uptake of cardiac surveillance was greater than the uptake of genetic testing (p?<?0.0001) among relatives of mutation positive probands. Within the group of at-risk, asymptomatic relatives of probands, cardiac screening and genetic testing were positive in 25 % and 40 % of cases, respectively. These data demonstrate the important role and utility of cascade cardiac screening and genetic testing in the care of patients and families with HCM or DCM. The approach to cardiac screening and genetic testing should be family-specific and requires expertise in the genetics of cardiomyopathy.  相似文献   
119.
Yin  Dake  Yu  Jiangping  Jin  Jiangping  Shen  Chao  Zhang  Li  Li  Xudong  Zhang  Keqin  Wang  Haitao 《Animal cognition》2023,26(4):1423-1430
Animal Cognition - Birds have the ability to assess the risk of predation in their environment and adjust their antipredation strategies based on this risk information. However, whether nest site...  相似文献   
120.
Paul Yu  Gary Fuller 《Synthese》1986,66(3):453-476
This essay is intended to be a systematic exposition and critique of Daniel Dennett's general views. It is divided into three main sections. In section 1 we raise the question of the nature of a plausible scientific psychology, and suggest that the question of whether folk psychology will serve as an adequate scientific psychology is of special relevance in a discussion of Dennett. We then characterize folk psychology briefly. We suggest that Dennett's views have undergone at least one major change, and proceed to discuss both his earlier and his later views.In section 2 we suggest that Dennett is correctly perceived as an instrumentalist in his earlier works. We think that Dennett later abandons this position because of general worries about instrumentalism and, more importantly, because Dennett became convinced that an instrumentalist conception of folk psychology will not enable us to vindicate the notions of personhood, moral agency, and responsibility. This left Dennett with a dilemma. On the one hand, he does not think that beliefs, etc., will turn out to be genuine scientific posits. On the other hand, he thinks that moral agency would be impossible if we could not treat beliefs, etc. as causally efficacious in some suitable sense.In section 3 we discuss Dennett's resolution of this dilemma. The key to his current view, we suggest, is the illata-abstracta distinction. Dennett holds that both illata and abstracta are real and have causal powers, even though only illata are genuine scientific posits. He suggests that beliefs etc. are abstracta, and are the subject matter of what he calls intentional system theory. The subject matter of another theory, what Dennett calls subpersonal cognitive psychology, are illata, which are subpersonal intentional states. The important point is that this distinction lets Dennett have it both ways: (i) Since beliefs are mere abstracta, we need not commit ourselves to the thesis that beliefs will turn out to be posits of an adequate scientific psychology. (ii) Since beliefs have causal power, we are assured of moral and rational agency. We shall argue that Dennett's current view is untenable. If we are right in our arguments, then Dennett's program to produce a scientifically plausible psychology, one that will turn out to vindicate folk psychology (in some suitable sense), is a failure. It fails in the following important ways: (i) What Dennett sketches — intentional system theory cum subpersonal cognitive psychology — is not a plausible scientific psychology. (ii) As a consequence, Dennett also fails to provide a satisfactory foundation for moral and rational agency.  相似文献   
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