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191.
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   
192.
We used 18F-fluorodeoxyglucose small-animal positron-emission tomography to determine whether different styles of coping with stress are associated with different patterns of neuronal activity in the hypothalamus. Adult rats were subjected to immobilization (IMO)-stress or to a non-immobilized condition for 30 min, in random order on separate days, each of which was followed by brain-scanning. Some rats in the immobilized condition were allowed to actively cope with the stress by chewing a wooden stick during IMO, while the other immobilized rats were given nothing to chew on. Voxel-based statistical analysis of the brain imaging data shows that chewing counteracted the stress-induced increased glucose uptake in the hypothalamus to the level of the non-immobilized condition. Region-of-interest analysis of the glucose uptake values further showed that chewing significantly suppressed stress-induced increased glucose uptake in the paraventricular hypothalamic nucleus and the anterior hypothalamic area but not in the lateral hypothalamus. Together with the finding that the mean plasma corticosterone concentration at the termination of the IMO was also significantly suppressed when rats had an opportunity to chew a wooden stick, our results showed that active coping by chewing inhibited the activation of the hypothalamic-pituitary-adrenal axis to reduce the endocrine stress response.  相似文献   
193.
National surveillance data indicate marked differences between Indigenous and other Australians in the prevalence of many sexually transmitted infections (STIs). Young Indigenous people bear a particularly high burden of these infections. A collaboration of university researchers, Indigenous health workers and young Indigenous people conducted 45 field interviews to examine how young Indigenous Australians keep themselves healthy and protected against STIs. Our findings emphasise the complexity of health behaviours, where individuals are rarely always ‘risky’ or always ‘safe’, as well as subtle gender differences in health practices. Preventive strategies employed by the young people were contingent on beliefs and knowledge about sexual partners, the type of relationship, the context of the sexual encounter and access to condoms. Tangible strengths such as young Indigenous people's commitments to condoms and STI screening should be celebrated and bolstered to enhance their ability to protect themselves against adverse health outcomes and enhance their resilience against STIs. Focusing on strengths helps to counter the deficit model of health commonly deployed in Indigenous health research and draws attention to health issues facing young Indigenous people and their communities, without reinforcing negative stereotypes or focusing solely on individual risk behaviour. We provide concrete recommendations for health promotion and education. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
194.
People can learn word–referent pairs over a short series of individually ambiguous situations containing multiple words and referents (Yu & Smith, 2007, Cognition 106: 1558–1568). Cross-situational statistical learning relies on the repeated co-occurrence of words with their intended referents, but simple co-occurrence counts cannot explain the findings. Mutual exclusivity (ME: an assumption of one-to-one mappings) can reduce ambiguity by leveraging prior experience to restrict the number of word–referent pairings considered but can also block learning of non-one-to-one mappings. The present study first trained learners on one-to-one mappings with varying numbers of repetitions. In late training, a new set of word–referent pairs were introduced alongside pretrained pairs; each pretrained pair consistently appeared with a new pair. Results indicate that (1) learners quickly infer new pairs in late training on the basis of their knowledge of pretrained pairs, exhibiting ME; and (2) learners also adaptively relax the ME bias and learn two-to-two mappings involving both pretrained and new words and objects. We present an associative model that accounts for both results using competing familiarity and uncertainty biases.  相似文献   
195.
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   
196.
This study assumes that performing household labor is a method of maintaining the marital relationship and investigates whether higher marital commitment (personal, moral, and structural) is associated with more time spent on housework. Data taken from the second wave of the National Survey of Families and Households on 3,428 paired spouses in the United States were used to test research hypotheses. Results indicate that (a) husbands with higher moral commitment, or those married to a wife with lower moral commitment, do more routine housework, and (b) husbands with stronger personal commitment do less routine housework and their wives do more. The interplay of gender ideology and marital commitment as they pertain to housework performance for each gender is discussed.  相似文献   
197.
The social brain undergoes developmental change during adolescence, and pubertal hormones are hypothesized to contribute to this development. We used fMRI to explore how pubertal indicators (salivary concentrations of testosterone, oestradiol and DHEA; pubertal stage; menarcheal status) relate to brain activity during a social emotion task. Forty‐two females aged 11.1 to 13.7 years underwent fMRI scanning while reading scenarios pertaining either to social emotions, which require the representation of another person’s mental states, or to basic emotions, which do not. Pubertal stage and menarcheal status were used to assign girls to early or late puberty groups. Across the entire sample, the contrast between social versus basic emotion resulted in activity within the social brain network, including dorsomedial prefrontal cortex (DMPFC), the posterior superior temporal sulcus, and the anterior temporal cortex (ATC) in both hemispheres. Increased hormone levels (independent of age) were associated with higher left ATC activity during social emotion processing. More advanced age (independent of hormone levels) was associated with lower DMPFC activity during social emotion processing. Our results suggest functionally dissociable effects of pubertal hormones and age on the adolescent social brain.  相似文献   
198.
Performing action has been found to have a greater impact on learning than observing action. Here we ask whether a particular type of action – the gestures that accompany talk – affect learning in a comparable way. We gave 158 6‐year‐old children instruction in a mental transformation task. Half the children were asked to produce a Move gesture relevant to the task; half were asked to produce a Point gesture. The children also observed the experimenter producing either a Move or Point gesture. Children who produced a Move gesture improved more than children who observed the Move gesture. Neither producing nor observing the Point gesture facilitated learning. Doing gesture promotes learning better than seeing gesture, as long as the gesture conveys information that could help solve the task.  相似文献   
199.
With its history dating back five millennia, the art of creating harmonious surroundings – commonly referred to as Feng Shui – has become deeply rooted in Chinese culture. Yet despite its significant effect on people's daily lives, a dearth of research is available on how Feng Shui influences consumers' decisions. This study investigates the influence of Feng Shui on customers' attitude based on their regulatory focus, providing suggestions for business opportunities. Three studies examine whether Feng Shui's goals influence participants' decisions and feelings of appropriateness. Study 1 demonstrated that the fit between Feng Shui's suggestions and consumers' regulatory focus impacted decision making. Participants were more likely to adopt the Feng Shui practitioner's suggestions of a goal compatible with the consumers' regulatory focus. Study 2 provided evidence that a regulatory focus also impacts participants' peace of mind. Study 3 tested whether the value experienced from regulatory fit is reflected in the price. Specifically, promotion‐oriented individuals feel more accepting of promotion‐focused Feng Shui that is consistent with an approach goal while prevention‐oriented individuals are more persuaded by prevention‐focused Feng Shui that is consistent with an avoidance goal. When the Feng Shui appeal is compatible with the self‐regulatory focus, individuals demonstrate a greater feeling of appropriateness and produce a higher level of peace of mind.  相似文献   
200.
In this study we clarified the multiple‐level effects of Confucian‐related work values, including self‐discipline and interpersonal ethics, on the performance of individuals and the team. Empirical data of 70 work teams with 472 team members from Taiwanese enterprises were collected to test our hypotheses. Results showed that, at the group level, shared team values of interpersonal ethics were positively related to team performance through the partial mediation of team cooperation. For cross‐level effect, shared team values of interpersonal ethics and individual member's self‐discipline values were both positively related to individual performance. The implications of Confucian dynamism work values on contemporary organizational management and indigenous Chinese team theories were provided.  相似文献   
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