首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2379篇
  免费   324篇
  国内免费   743篇
  2024年   8篇
  2023年   35篇
  2022年   102篇
  2021年   106篇
  2020年   119篇
  2019年   104篇
  2018年   130篇
  2017年   134篇
  2016年   136篇
  2015年   77篇
  2014年   120篇
  2013年   221篇
  2012年   162篇
  2011年   205篇
  2010年   164篇
  2009年   174篇
  2008年   164篇
  2007年   246篇
  2006年   233篇
  2005年   167篇
  2004年   115篇
  2003年   82篇
  2002年   71篇
  2001年   52篇
  2000年   35篇
  1999年   37篇
  1998年   26篇
  1997年   28篇
  1996年   16篇
  1995年   12篇
  1994年   12篇
  1993年   9篇
  1992年   18篇
  1991年   14篇
  1990年   13篇
  1989年   12篇
  1988年   2篇
  1987年   6篇
  1986年   9篇
  1985年   8篇
  1984年   8篇
  1983年   8篇
  1982年   12篇
  1981年   12篇
  1980年   9篇
  1979年   3篇
  1977年   2篇
  1973年   2篇
  1968年   1篇
  1966年   1篇
排序方式: 共有3446条查询结果,搜索用时 15 毫秒
141.
以大学生为被试,采用不同情绪效价的条件命题作为实验材料,运用眼动仪器记录被试进行条件推理的过程和结果,探讨了材料情绪性对条件推理的影响状况.实验采用3(材料情绪性:正性情绪、负性情绪、中性情绪)×4(推理形式:MP、DA、AC、MT)的重复测量实验设计.研究结果发现,正性和负性情绪材料的条件推理成绩显著地低于中性情绪材料,结果支持抑制假说.  相似文献   
142.
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   
143.
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   
144.
145.
The effect of spacing in relation to word segmentation was examined for four groups of non-native Chinese speakers (American, Korean, Japanese, and Thai) who were learning Chinese as second language. Chinese sentences with four types of spacing information were used: unspaced text, word-spaced text, character-spaced text, and nonword-spaced text. Also, participants' native languages were different in terms of their basic characteristics: English and Korean are spaced, whereas the other two are unspaced; Japanese is character based whereas the other three are alphabetic. Thus, we assessed whether any spacing effects were modulated by native language characteristics. Eye movement measures showed least disruption to reading for word-spaced text and longer reading times for unspaced than character-spaced text, with nonword-spaced text yielding the most disruption. These effects were uninfluenced by native language (though reading times differed between groups as a result of Chinese reading experience). Demarcation of word boundaries through spacing reduces non-native readers' uncertainty about the characters that constitute a word, thereby speeding lexical identification, and in turn, reading. More generally, the results indicate that words have psychological reality for those who are learning to read Chinese as a second language, and that segmentation of text into words is more beneficial to successful comprehension than is separating individual Chinese characters with spaces.  相似文献   
146.
147.
Set up in 2011, the ethics committee at the teaching hospital in Bordeaux, although it is now obsolete in its organisation because of the "standardisation" in early 2012 of regional ethics groups, was nevertheless an original structure which deserves to be analysed for several reasons. First of all, why have a hospital ethics committee? Then, to do what? Finally, it is interesting to give a few indications about the working of this committee.  相似文献   
148.
Two studies examined topic avoidance in Chinese and Taiwanese opposite‐sex friendships and romantic relationships. Five areas of topic avoidance emerged through analytic induction and cluster analysis: negative appraisal, relational issues, sexual issues, politics, and personal experience. Partner protection, negative relational impact, and self inefficacy emerged as the most common reasons for avoidance. Results revealed that friends, relative to romantic partners, engaged in higher levels of topic avoidance. Taiwanese participants, moreover, avoided discussing politics to a greater extent than did mainland Chinese participants. Lacking closeness was the main reason behind avoidance of political discussion. Topic avoidance was also linked to relationship quality, as relational satisfaction negatively predicted relational issue avoidance and topic avoidance breadth (i.e. the number of topics regularly avoided in the relationship). The authors explain these and other findings based on Chinese cultural codes and historically‐embedded concepts that shape interpersonal interaction.  相似文献   
149.
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   
150.
The study investigated the effectiveness of different camouflage designs using a computational image quality index. Camouflaged human targets were presented on a natural landscape and the targets were designed to be similar to the landscape background with different levels of background similarity as estimated by the image index. The targets were presented in front of the observer (central 0 degrees) or at different angles in the left (-7 degrees, -14 degrees, -21 degrees) or right (+7 degrees, +14 degrees, +21 degrees) visual fields. The observer had to detect the target using peripheral vision if the target appeared in the left and right visual fields. The camouflage effectiveness was assessed by detection hit rates, detection times, and subjective ratings on detection confidence and task difficulty. The study showed that the psychophysical measures correlated well with the image similarity index, suggesting a potentially more efficient camouflage effectiveness assessment tool if the relationship between the psychophysical results and the index can be quantified in the future.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号