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21.
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   
22.
The growing emphasis on the importance of publishing scientific findings in the academic world has led to increasing prevalence of potentially significant publications in which scientific and ethical rigour may be questioned. This has not only hindered research progress, but also eroded public trust in all scientific advances. In view of the increasing concern and the complexity of research misconduct, the Committee on Publication Ethics (COPE) was established in 1997 to manage cases with ethical implications. In order to review the outcomes of cases investigated by COPE, a total of 408 cases that had been managed by COPE were successfully extracted and analysed with respect to 7 distinct criteria. The results obtained indicate that the number of ethical implications per case has not changed significantly (p?>?0.01) since the year COPE was instigated. Interestingly, the number of ethical cases, and to some extent, research misconduct, is not diminishing. Therefore, journal editors and publishers need to work closely together with COPE to inculcate adoption of appropriate research ethics and values in younger researchers while discouraging others from lowering standards. It is hoped that with a more concerted effort from the academic community and better public awareness, there will be fewer incidences of ethically and scientifically challenged publications. The ultimate aim being to enhance the quality of published works with concomittant public trust in the results.  相似文献   
23.
When people seek to impress others, they often do so by highlighting individual achievements. Despite the intuitive appeal of this strategy, we demonstrate that people often prefer potential rather than achievement when evaluating others. Indeed, compared with references to achievement (e.g., "this person has won an award for his work"), references to potential (e.g., "this person could win an award for his work") appear to stimulate greater interest and processing, which can translate into more favorable reactions. This tendency creates a phenomenon whereby the potential to be good at something can be preferred over actually being good at that very same thing. We document this preference for potential in laboratory and field experiments, using targets ranging from athletes to comedians to graduate school applicants and measures ranging from salary allocations to online ad clicks to admission decisions. (PsycINFO Database Record (c) 2012 APA, all rights reserved).  相似文献   
24.
A hypothesis was examined, that gelotophobia (the fear of being laughed at) was negatively related to Type I thinking styles and positively related to Type II thinking styles as defined in Sternberg's theory of mental self-government. 431 university students (250 women, 181 men; M age = 20.4 yr., SD = 1.2) completed self-report measures of gelotophobia (GELOPH <15>) and thinking styles (Thinking Styles Inventory-Revised). Correlation and regression analyses were conducted. The results indicated that gelotophobia was negatively and significantly related to four Type I thinking styles (legislative, judicial, liberal, and hierarchical thinking styles) and a Type III thinking style (external), while it was positively and significantly related to a Type II thinking style (conservative). Thinking styles uniquely explained 18% of the total variance in gelotophobia scores. Possible interventions from the perspective of thinking styles in the treatment of gelotophobia were discussed.  相似文献   
25.
利用眼动分析技术,通过设置不同难度和分值的计算项目,探讨了在有时间压力下学习者的学习时间分配。结果发现:(1)在首次项目选择上,学习者优先选择学习率最高的项目;(2)在学习过程中,学习者的项目选择次序也是根据学习率由高到低。总之,在学习时间分配上,如果需要权衡难度与分值,学习者会考虑单位时间的获益,也就是以学习率为议程的主要依据。研究不仅利用眼动分析技术证实了基于议程的学习时间分配模型,而且进一步揭示了学习率是设置学习时间分配议程的重要依据。  相似文献   
26.
执行功能缺陷是网络成瘾发生、维持和复发的原因之一,以往研究侧重于探讨网络成瘾者注意控制、反应抑制等执行功能成分的损伤状况,而其记忆抑制状况尚不清楚。本研究通过考察网络成瘾大学生的提取诱发遗忘(RIF)来探讨其记忆抑制的特点及RIF的产生机制。结果发现:低网络成瘾个体在高项目竞争强度下表现出显著的RIF,在低项目竞争强度下未产生;高网络成瘾个体在低项目竞争强度下表现出显著的RIF,在高项目竞争强度下未产生。结果表明网络成瘾大学生的记忆抑制能力受损严重,其在低项目竞争强度下易受相关代价与效益问题(CCB)影响而产生干扰性RIF。  相似文献   
27.
逻辑学以及形式语义学对汉语连动结构的研究一般都停留在一阶逻辑的层面上,即通过一阶逻辑中的形式化方法给出连动结构的形式化构造。但是在对不同类型连动结构进行更为深入的研究时,一阶逻辑这一工具就显的不够了。本文中,作者将以因果型连动结构为研究对象,利用一阶模态逻辑为其构建形式系统并尝试给出因果型连动结构和途径–目的型连动结构之间的区别和联系。  相似文献   
28.

The orienting of attention has been found to be influenced by the previous cueing status in a spatial-cueing paradigm. The explanation for this sequence effect remains uncertain. This study separated the involuntary and the voluntary components of arrow cueing by manipulating the predicted target locations. For example, a left arrow cue may have indicated that the target was more likely to appear at the up location. Therefore, three trial types were repeated or switched between trials: cued (targets appeared along the direction of the arrows), predicted (targets appeared at the locations predicted by the arrows), and unrelated (targets appeared at the other two locations, neither cued nor predicted). RTs of cued trials were found to be significantly facilitated after a previous cued trial; however, the same effect was not observed for predicted trials. The results suggest that significant sequence effects are induced only in the involuntary component of arrow cueing. The findings support the feature-integration hypothesis for the sequence effect of symbolic cueing.

  相似文献   
29.
Yong Huang 《Philosophia》2018,46(4):877-894
Moral relativism familiar in the Western philosophical tradition, according to David Lyons, is either agent relativism (moral judgments are relative to the standards of the agent or the agent group) or appraiser relativism (moral judgments are relative to the standards of the appraiser(s) or appraiser group(s)). As Lyons has convincingly argued, they are both problematic. However, in the ancient Chinese Daoist classic, the Zhuangzi, we can find a different type of moral relativism, which I call patient relativism (moral judgments are relative to the patients’ standards). In the essay, I aim to argue in what sense Zhuangzi is a patient relativist and how patient relativism can avoid the problem of agent relativism and appraiser relativism.  相似文献   
30.
关系语义是相干逻辑中最为重要的语义学之一,但是关系语义一开始就以"纯粹"的形式语义的面貌出现,其中三元关系R的直观意思是什么并不清楚,于是出现了关于关系语义的多种解释。我们认为,R所代表的是推理规则集、前提集和结论集三者之间的关系,据此提出了推理语义。推理语义以推理的形式结构为背景,有明确的直观意义。本文以相干逻辑系统R+为例,证明出推理语义是与关系语义等价的语义。从推理语义与关系语义的这个等价关系上看,推理语义完全可以作为对于关系语义直观解释的一个中间环节。由此不仅使得关系语义有了推理结构的解释,同时说明了相干逻辑是一种关于推理的逻辑。这与相干逻辑产生的历史也完全吻合。  相似文献   
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