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   612篇
  免费   40篇
  2023年   3篇
  2021年   8篇
  2020年   18篇
  2019年   24篇
  2018年   31篇
  2017年   22篇
  2016年   28篇
  2015年   17篇
  2014年   15篇
  2013年   91篇
  2012年   34篇
  2011年   40篇
  2010年   29篇
  2009年   27篇
  2008年   32篇
  2007年   27篇
  2006年   23篇
  2005年   21篇
  2004年   18篇
  2003年   16篇
  2002年   14篇
  2001年   3篇
  2000年   6篇
  1999年   7篇
  1998年   6篇
  1997年   4篇
  1995年   2篇
  1993年   4篇
  1992年   6篇
  1991年   3篇
  1990年   6篇
  1989年   7篇
  1986年   4篇
  1983年   2篇
  1982年   2篇
  1981年   2篇
  1980年   5篇
  1979年   4篇
  1978年   4篇
  1977年   5篇
  1976年   4篇
  1973年   3篇
  1969年   2篇
  1968年   2篇
  1967年   2篇
  1966年   2篇
  1956年   1篇
  1955年   1篇
  1952年   1篇
  1950年   1篇
排序方式: 共有652条查询结果,搜索用时 15 毫秒
111.
We describe the development and evaluation of a computer-controlled system for delivering odors in a magnetic resonance imaging (MRI) environment. The system allows a timely presentation of different odors in synchrony with MRI sequences and participant’s inspiration phase. The rise/fall time of odor deliverance has been optimized to generate prompt and strong stimulations. Equipped with a user-friendly programming interface, the system can be used reliably in a wide range of experimental paradigms. We have paid particular attention to developing a portable system that is relatively easy, rapid, and inexpensive to replicate. The equipment has been tested in a 3-Tesla MRI in a boxcar paradigm, in which stimulation conditions alternated with rest periods (no stimulation). The experiment demonstrated the good functioning of the device and its efficiency in producing the expected activation in the olfactory cortex; it also revealed some methodological and technical aspects to be improved.  相似文献   
112.
The main purpose of this study was to examine whether the use of internal imagery would affect high jumping performance for active high jumping athletes. Over a period of six weeks, a group of active high jumpers were trained with an internal imagery program for a total of 72 minutes. This group was compared to a control group consisting of active high jumpers that only maintained their regular work-outs during the same time period. Four variables were measured; jumping height, number of failed attempts, take-off angle, and bar clearance. There was a significant improvement on bar clearance for the group that trained imagery (p < 0.05) but not for the control group. No other differences were found. The results suggest that internal imagery training may be used to improve a component of a complex motor skill. Possible explanations and future recommendations are discussed.  相似文献   
113.
The general magnocellular theory postulates that dyslexia is the consequence of a multimodal deficit in the processing of transient and dynamic stimuli. In the auditory modality, this deficit has been hypothesized to interfere with accurate speech perception, and subsequently disrupt the development of phonological and later reading and spelling skills. In the visual modality, an analogous problem might interfere with literacy development by affecting orthographic skills. In this prospective longitudinal study, we tested dynamic auditory and visual processing, speech-in-noise perception, phonological ability and orthographic ability in 62 five-year-old preschool children. Predictive relations towards first grade reading and spelling measures were explored and the validity of the global magnocellular model was evaluated using causal path analysis. In particular, we demonstrated that dynamic auditory processing was related to speech perception, which itself was related to phonological awareness. Similarly, dynamic visual processing was related to orthographic ability. Subsequently, phonological awareness, orthographic ability and verbal short-term memory were unique predictors of reading and spelling development.  相似文献   
114.
The current study examined social support and stress as mediators of the hostility—coronary heart disease (CHD) relationship as suggested by the psychosocial vulnerability model in a sample of low-income African Americans. Among 95 CHD patients and 30 healthy controls, hostility was negatively correlated with social support, but was not related to minor stress. CHD patients endorsed higher levels of hostility; however, the relationship between hostility and CHD status was diminished once stress and social support were included in the model. This study lends partial support for the psychosocial vulnerability model of hostility in African Americans, but suggests that the relationship between hostility and stress may be impacted by socioeconomic status.  相似文献   
115.
Reasoning with non-symbolic numerosities is suggested to be rooted in the Approximate Number System (ANS) and evidence pointing to a relationship between the acuity of this system and mathematics is available. In order to use the acuity of this ANS as a screening instrument to detect future math problems, it is important to model ANS acuity over development. However, whether ANS acuity and its development have been described accurately can be questioned. Namely, different tasks were used to examine the developmental trajectory of ANS acuity and studies comparing performances on these different tasks are scarce. In the present study, we examined whether different tasks designed to measure the acuity of the ANS are comparable and lead to related ANS acuity measures (i.e., the concurrent validity of these tasks). We contrasted the change detection task, which is used in infants, with tasks that are more commonly used in older children and adults (i.e., comparison and same-different tasks). Together, our results suggest that ANS acuity measures obtained with different tasks are not related. This poses serious problems for the comparison of ANS acuity measures derived from different tasks and thus for the establishment of the developmental trajectory of ANS acuity.  相似文献   
116.
Sub-Saharan Africans living in Belgium (N = 69) completed a culture-free intelligence test in a simulated job selection environment. Prior to testing, the authors instructed participants that Africans' average performance on this test was generally better (positive comparison), worse (negative comparison), or equal to Belgians' performance. In a control condition, no such information was given. Results indicated that, compared with the equal and control conditions, performance was lower when intergroup comparisons were negative. In the former condition, participants were also more likely to endorse external factors that may account for lower performance. The authors interpreted the findings in line with stereotype threat theory (C. M. Steele & J. Aronson, 1995). In the context of job selection, the validity of intelligence tests conducted with members of stigmatized groups may be affected by the salience of social stereotypes and intergroup social comparisons.  相似文献   
117.
The present study examined the moderating influence of the Big Five personality factors in the relationship between five symbolic, trait‐based inferences about organizations (Sincerity, Excitement, Competence, Prestige, and Ruggedness) and organizational attractiveness. Drawing on the similarity‐attraction paradigm, six hypotheses were formulated, stating that the relationship between trait‐based inferences and organizational attractiveness would be stronger for persons who perceive the organization as similar to them. Results of moderated regression analyses on data from a sample of 245 prospective applicants for the Belgian military revealed two significant two‐way interactions, showing that Sincerity was positively related to organizational attractiveness only for individuals high on Conscientiousness, and that the relationship between Excitement and organizational attractiveness is more positive for individuals high on Openness to Experience. Practical implications, strengths and limitations, as well as directions for further research are presented.  相似文献   
118.
119.
Male rats were given bilateral lesions in either the anterior or posterior ventromedial hypothalamus (VMH). The intermale aggressive behaviour of these animals within their own territory was observed before and after the surgical procedure and compared with the behaviour of sham-operated animals. The effects of anterior VMH lesions include an increased tendency to respond with frontal threatening upon approach of a conspecific male. This behaviour closely resembles the aggressive responses described in “shock-induced aggression” tests. Posterior VMH lesions facilitate territorial aggressive behaviour characterized by approaching the opponent followed by lateral threatening and fighting. It is suggested that 2 distinct neural substrates exist, which serve to inhibit defensive (anterior-VMH) and offensive (posterior-VMH) intermale aggression, respectively.  相似文献   
120.
Conclusion Does ethics have adequate general theories? Our analysis shows that this question does not have a straightforward answer since the key terms are ambiguous. So we should not concentrate on the answer but on the question itself. Ethics stands for many things, but we let that pass. Adequate may refer to varied arrays of methodological principles which are seldom fully articulated in ethics. General is a notion with at least three meanings. Different kinds of generality may be at cross-purposes, so we must not expect theories to be general in sundry senses. Theory, for that matter, is itself ambiguous. Some thinkers say that ethics cannot have theories, while others deny it. We doubt whether opposing parties are talking about the same things.No wonder, then, that controversies in ethics are long-lasting and unproductive. We hope that the methodology we have presented will alleviate some of them. The examples we chose show that this is feasible. Views such as Hare's and Jonsen and Toulmin's which are seemingly wide apart, show convergence if we put them in a methodological perspective.Our analysis also suggests that many alleged differences between science and ethics could fade away if methodology is brought to bear on them. Specifically, the idea that ethics compares poorly with science in view of limited generality, or poor means of justification, is unfounded. Those who defend this view over-rate the powers of science.  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