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   4145篇
  免费   263篇
  2023年   31篇
  2022年   53篇
  2021年   67篇
  2020年   135篇
  2019年   104篇
  2018年   203篇
  2017年   197篇
  2016年   217篇
  2015年   168篇
  2014年   184篇
  2013年   620篇
  2012年   220篇
  2011年   226篇
  2010年   144篇
  2009年   149篇
  2008年   208篇
  2007年   200篇
  2006年   154篇
  2005年   102篇
  2004年   105篇
  2003年   120篇
  2002年   97篇
  2001年   74篇
  2000年   91篇
  1999年   46篇
  1998年   36篇
  1997年   30篇
  1996年   29篇
  1995年   16篇
  1994年   18篇
  1993年   21篇
  1992年   16篇
  1991年   17篇
  1990年   14篇
  1989年   13篇
  1988年   9篇
  1987年   9篇
  1984年   12篇
  1983年   13篇
  1982年   17篇
  1981年   9篇
  1980年   13篇
  1979年   11篇
  1978年   12篇
  1977年   9篇
  1975年   15篇
  1974年   9篇
  1972年   11篇
  1971年   14篇
  1970年   12篇
排序方式: 共有4408条查询结果,搜索用时 31 毫秒
941.
Learning about hereditary cancer may influence an individual’s self-concept, which otherwise represents a complex but stable cognitive structure. Recently, a 20-statement self-concept scale, with subscales related to stigma-vulnerability and bowel symptom-related anxiety, was developed for Lynch syndrome. We compared the performance of this scale in 591 mutation carriers from Denmark, Sweden and Canada. Principal component analysis identified two sets of linked statements—the first related to feeling different, isolated and labeled, and the second to concern and worry about bowel changes. The scale performed consistently in the three countries. Minor differences were identified, with guilt about passing on a defective gene and feelings of losing one’s privacy being more pronounced among Canadians, whereas Danes more often expressed worries about cancer. Validation of the Lynch syndrome self-concept scale supports its basic structure, identifies dependence between the statements in the subscales and demonstrates its applicability in different Western populations.  相似文献   
942.
Long-term synaptic plasticity exhibits distinct phases. The synaptic tagging hypothesis suggests an early phase in which synapses are prepared, or "tagged," for protein capture, and a late phase in which those proteins are integrated into the synapses to achieve memory consolidation. The synapse specificity of the tags is consistent with conventional neural network models of associative memory. Memory consolidation through protein synthesis, however, is neuron specific, and its functional role in those models has not been assessed. Here, using a theoretical network model, we test the tagging hypothesis on its potential to prolong memory lifetimes in an online-learning paradigm. We find that protein synthesis, though not synapse specific, prolongs memory lifetimes if it is used to evaluate memory items on a cellular level. In our model we assume that only "important" memory items evoke protein synthesis such that these become more stable than "unimportant" items, which do not evoke protein synthesis. The network model comprises an equilibrium distribution of synaptic states that is very susceptible to the storage of new items: Most synapses are in a state in which they are plastic and can be changed easily, whereas only those synapses that are essential for the retrieval of the important memory items are in the stable late phase. The model can solve the distal reward problem, where the initial exposure of a memory item and its evaluation are temporally separated. Synaptic tagging hence provides a viable mechanism to consolidate and evaluate memories on a synaptic basis.  相似文献   
943.
In a study with 365 teacher students, 447 teacher trainees, and 123 teachers, the ability to detect students’ deception was tested. Participants judged the credibility of videotaped students who were accused of academic dishonesty (having cheated in a test). Half of these messages were actually true (students had not cheated on the test) and half of them were deceptive (students had cheated on the test). As expected and in line with findings on the influence of expertise on the ability to detect deception from other fields, we found that the overall accuracy rate of teachers was not higher than that of teacher trainees and teacher students. Moreover, we found no effect of teaching experience (years working as a teacher) on overall detection of deception accuracy. Interestingly, teachers were found to have a stronger truth bias and therefore had a lower accuracy in detecting deceptive messages than teacher students and teacher trainees (veracity effect). While teacher characteristics accounted for very little variance, senders’ opportunity to prepare and their gender had strong effects. Detection accuracy was higher for messages where the student had no chance to prepare before being accused of cheating. Overall, independent, or experience, participants hold inaccurate beliefs about deception.  相似文献   
944.
The Mirror Neuron System hypothesis stating that observed actions are projected onto the observer’s own action system assigns an important role to development, because only actions mastered by the observer can be mirrored. The purpose of the present study was to investigate whether there is evidence of a functioning mirror neuron system (MNS) in 8-month-old infants. High-density EEG was used to assess the mu rhythm desynchronization in an action observation task where the infants observed a live model. To reduce noise, ICA decompositions were used. The results show a higher desynchronization of the mu rhythm when infants observed a goal-directed action than when they observed a spatially similar non-goal-directed movement. The localizations of the sources are in agreement with those proposed by the MNS hypothesis. This indicates that the MNS is functioning at this age.  相似文献   
945.
Given a reasonable coherentist view of justification in ethics, applied ethics, as here conceived of, cannot only guide us, in our practical decisions, but also provide moral understanding through explanation of our moral obligations. Furthermore, applied ethics can contribute to the growth of knowledge in ethics as such. We put moral hypotheses to crucial test in individual cases. This claim is defended against the challenges from moral intuitionism and particularism.  相似文献   
946.
Die chronische bipolare Depression bei ?lteren Menschen ist eine klinische Herausforderung und erfordert unter Umst?nden, wie der vorliegende Fallbericht zeigt, Behandlungswege, die von Leitlinien nicht unbedingt abgedeckt werden.  相似文献   
947.
Studies of children's knowledge of the Earth have led to very different conclusions: some appear to show that children construct their own, non‐scientific ‘theories’ (mental models) of the flat, hollow or dual Earth. Others indicate that many young children have some understanding of the spherical (scientific) Earth, and that their knowledge lacks the coherence of mental models. The reasons for these contrasting views were tested by interviewing French children (N = 178) aged 5–11 years and varying the different methods used in previous research, namely the types of questions (open and forced‐choice), the form of representation (two‐dimensional pictures and three‐dimensional models), and the method of analysis (the mental model theorists' coding scheme and a statistical test for associations using MANOVA). Forced‐choice questions resulted in higher proportions of scientific answers than open questions, and children appeared to have naïve mental models of the Earth only when the mental model theorists' coding scheme was used. These findings support the view that children tend to have ‘fragments’ of scientific knowledge, and that naïve mental models of the Earth are methodological artifacts. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
948.
Emotionally expressive faces have shown enhanced detectability over neutral faces, but little is known about the effect of eye gaze on detecting the presence of emotional faces. Emotional expressions and gaze direction are both cues to the intentions of another person, and gaze direction has been shown to affect recognition accuracy and perceived intensity of emotional faces. The current study showed that fearful faces were detected more frequently with an averted gaze than with a direct gaze in an attentional blink task, whereas angry and happy faces were detected more frequently with a direct gaze than with an averted gaze. The results are in line with the shared signal hypothesis and appraisal theory and suggest that selection for awareness was based on a rapid evaluation of the intentions of another person as conveyed by their facial expression and gaze direction.  相似文献   
949.
Owing to the declining length of patients' hospital stay in recent years, chaplains need evidence-based criteria to decide which patients are likely to have the greatest psychosocial and/or religious-spiritual needs. Therefore, the present pilot study aims at sorting out evidence-based criteria to assess patients with lack of coping resources. A total of 610 patients in the German-speaking part of Switzerland were surveyed with regard to their psychosocial health. The results suggest that lack of vitality (including health condition), lack of support and lack of faith (including spiritual struggle) are valid and reliable criteria for chaplains as internal triggers for pastoral visitation.  相似文献   
950.
Although the majority of research focuses on the risks and disadvantages of online gaming, the present authors suggest that online games also represent new ways of satisfying basic human needs within the conditions of modern society. The aim of our present study was to reveal and operationalize the components of the motivational basis of online gaming. A total 3,818 persons (90.6% males; mean age 20.9 years, SD = 5.81) were recruited through websites providing online games. A combined method of exploratory and confirmatory factor analysis was applied. The results confirmed our preliminary model as we identified seven motivational factors (social, escape, competition, coping, skill development, fantasy, and recreation), which were used to develop the 27-item Motives for Online Gaming Questionnaire (MOGQ). The seven dimensions identified seem to cover the full range of possible motives for gaming, and the MOGQ proved to be an adequate measurement tool to assess these motives.  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