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211.
该研究以69名5岁幼儿为被试,通过创设猜测物体的问题情境,以考察幼儿提问对其解决猜测物体的问题的影响.结果表明:(1)面对问题情境,幼儿运用提问解决问题的正确率显著高于不提问直接猜测的正确率.(2)幼儿运用两阶段整体策略和逐一排除策略提问来帮助其问题解决的效果好于直接猜测的效果.(3)幼儿提出混合类问题和外在感知类问题来帮助其解决猜测物体问题的效果好于提出内在属性类问题.  相似文献   
212.
Stress can disrupt endocrine signalling in the male reproductive axis through high concentrations of glucocorticoids, the hallmark of stress. Our previous work revealed that a stress level of exogenous glucocorticoids could induce apoptosis of rat Leydig cells, which are the primary source of testosterone. The aim of this study was to investigate whether stress can induce apoptosis in rat Leydig cells in vivo and, if so, whether the process is the result of a direct effect of glucocorticoids. In a chronically stressed rat model, serum corticosterone concentration was increased significantly whereas serum testosterone was decreased. The frequency of apoptotic Leydig cells in stressed rats was also increased. Adrenalectomised rats subjected to chronic stress showed an elevated serum testosterone, while the apoptotic frequency of Leydig cells was not increased. It was established that glucocorticoid-induced Leydig cell apoptosis is mediated by glucocorticoid receptors (GRs), which translocate from cytoplasm to nucleus. Adenovirus microRNA-induced downregulation of GR expression in vitro alleviated the corticosterone-induced increase in apoptosis of Leydig cells. These results indicate that the stress-induced increase in corticosterone secretion resulted in apoptosis in rat Leydig cells in vivo, and thereby decreased testosterone synthesis.  相似文献   
213.
It is established that stress impairs spatial learning and memory via the hypothalamus-pituitary-adrenal axis response. Dopamine D1 receptors were also shown to be responsible for a stress-induced deficit of working memory. However, whether stress affects the subsequent emotional learning and memory is not elucidated yet. Here, we employed the well-established one-trial step-through task to study the effect of an acute psychological stress (induced by tail hanging for 5, 10, or 20?min) on emotional learning and memory, and the possible mechanisms as well. We demonstrated that tail hanging induced an obvious stress response. Either an acute tail-hanging stress or a single dose of intraperitoneally injected dopamine D1 receptor antagonist (SCH23390) significantly decreased the step-through latency in the one-trial step-through task. However, SCH23390 prevented the acute tail-hanging stress-induced decrease in the step-through latency. In addition, the effects of tail-hanging stress and/or SCH23390 on the changes in step-through latency were not through non-memory factors such as nociceptive perception and motor function. Our data indicate that the hyperactivation of dopamine D1 receptors mediated the stress-induced deficit of emotional learning and memory. This study may have clinical significance given that psychological stress is considered to play a role in susceptibility to some mental diseases such as depression and post-traumatic stress disorder.  相似文献   
214.
215.
The issue of reference frame is central to theories of spatial representations. Various classifications have been made for different types of reference frames, along with prototypical research paradigms to distinguish between them. This article focuses on the configuration error paradigm proposed by Wang and Spelke (Cognition 77:215-250, 2000) that has been used to examine the nature of the spatial representations underlying object localization during self-movement. Three basic models of spatial memory and spatial updating are discussed, as well as the assumptions behind the configuration error paradigm, to distinguish between static representations, such as the traditional allocentric cognitive map and the egocentric snapshots, and dynamic representations, such as the egocentric updating system. Recent experimental findings are reexamined and shown to be consistent with multiple models, among which the egocentric-updating-and-reload model with an enduring egocentric component provides the simplest interpretations.  相似文献   
216.
Objective: Preclinical models, receptor localization, and genetic linkage data support the role of D4 receptors in the etiology of ADHD. This proof-of-concept study was designed to evaluate MK-0929, a selective D4 receptor antagonist as treatment for adult ADHD. Method: A randomized, double-blind, placebo-controlled, crossover study was conducted in adults with primary ADHD. The primary end point was changed from baseline in total score on the Adult ADHD Investigator Symptom Rating Scale following a 4-week treatment regimen. Additional measures included Clinical Global Impression-Severity Scale, Hospital Anxiety and Depression Scale, and Brown Attention Deficit Disorder Scale and D4 genotype analysis. Results: No statistically significant treatment differences were found between MK-0929 and placebo in any of the primary or secondary assessments. Conclusion: Results from this study suggest that blockade of the D4 receptor alone is not efficacious in the treatment of adult ADHD.  相似文献   
217.
The goal of this study was to identify diverse profiles of Asian American women's and men's adherence to values that are salient in Asian cultures (i.e., conformity to norms, family recognition through achievement, emotional self-control, collectivism, and humility). To this end, the authors conducted a latent profile analysis using the 5 subscales of the Asian American Values Scale-Multidimensional in a sample of 214 Asian Americans. The analysis uncovered a four-cluster solution. In general, Clusters 1 and 2 were characterized by relatively low and moderate levels of adherence to the 5 dimensions of cultural values, respectively. Cluster 3 was characterized by the highest level of adherence to the cultural value of family recognition through achievement, whereas Cluster 4 was typified by the highest levels of adherence to collectivism, emotional self-control, and humility. Clusters 3 and 4 were associated with higher levels of depressive symptoms than Cluster 1. Furthermore, Asian American women and Asian American men had lower odds of being in Cluster 4 and Cluster 3, respectively. These findings attest to the importance of identifying specific patterns of adherence to cultural values when examining the relationship between Asian Americans' cultural orientation and mental health status.  相似文献   
218.
Formerly, researchers often treated adult attachment as a trait‐like construct with consistency across relationship contexts. However, recent studies have shown that people possess multiple relationship‐specific attachment representations, and inter‐correlations among them are only in a small‐to‐medium range. The aim of this study is to test whether these variable‐centred results could be replicated in China and further supplement them with a person‐centred analysis focusing on identifying prototypical patterns of multiple working models across relationships. We administrated measurements of general and four relationship‐specific (mother/father/best friend/romantic partner) working models and indicators of psychological adjustment upon 302 Chinese college students. Results from variable‐centred analysis demonstrated the cross‐relationship variability in working models. Furthermore, global indicators of psychological adjustment were better predicted by general models, while relationship‐specific indicators were better predicted by corresponding relationship‐specific models. These results largely replicate previous Western studies, supporting the existence of multiple attachment representations in China. In person‐centred analysis, a latent profile analysis identified four typical classes of working model profiles: all‐average, all‐secure, romantic‐insecure and peer‐secure. These classes differed not only in the cross‐relationship variability of their working models, but also in their levels of psychological adjustment. These interesting patterns may have theoretical implications and are worthy of further examination.  相似文献   
219.
Immigration labor in global cities is often framed in a dichotomy of skilled and nonskilled and explained from different perspective. Based on narratives of skilled immigrants from mainland China in postcolonial Hong Kong, this study shifts the focus of attention from generalized dissimilarities between migrant groups determined by the level of skills to commonalities of experience shaped by the broader social and cultural forces of their spatial, economic and political environments. It points to the importance of ??border?? in shaping the mode of incorporation of skilled migrants to localities in global city. It shows that skilled mainland immigrants in Hong Kong are deeply embedded in an overarching xin yimin (new immigrants) discourse according to which the Hong Kong?CChina border distinguishes all mainland immigrants from Hong Kong citizens regardless of the level of skills they possess. This discourse is associated with and defined by the cultural meaning of border between Hong Kong and China produced in the colonial past and reproduced in the postcolonial present. Despite being highly educated and skilled, mainland Chinese professionals experienced countless negotiation of sameness and difference in their everyday encountering localities and making place. The stories presented here ask us to rethink the assumptions informing the analytical distinctions between skilled and non-skilled and call for ??unifying?? skilled and non-skilled migration in global cities methodologically and theoretically.  相似文献   
220.
Many studies have suggested that emotional stimuli orient and engage attention. There is also evidence that animate stimuli, such as those from humans and animals, cause attentional bias. However, categorical and emotional factors are usually mixed, and it is unclear to what extent human context influences attentional allocation. To address this issue, we tracked participants' eye movements while they viewed pictures with animals and inanimate images (i.e., category) as focal objects. These pictures had either negative or neutral emotional valence, and either human body parts or nonhuman parts were near the focal objects (i.e., context). The picture's valence, arousal, position, size, and most of the low-level visual features were matched across categories. The results showed that nonhuman animals were more likely to be attended to and to be attended to for longer times than inanimate objects. The same pattern held for the human contexts (vs. nonhuman contexts). The effects of emotional valence, category, and context interacted. Specifically, in images with a negative valence, focal animals and objects with human context had comparable numbers of gaze fixations and gaze duration. These results highlighted the attentional bias to animate parts of a picture and clarified that the effects of category, valence, and picture context interacted to influence attentional allocation.  相似文献   
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