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   10933篇
  免费   519篇
  国内免费   3篇
  2020年   139篇
  2019年   148篇
  2018年   257篇
  2017年   231篇
  2016年   239篇
  2015年   174篇
  2014年   198篇
  2013年   805篇
  2012年   333篇
  2011年   367篇
  2010年   224篇
  2009年   185篇
  2008年   292篇
  2007年   277篇
  2006年   259篇
  2005年   212篇
  2004年   204篇
  2003年   181篇
  2002年   193篇
  2001年   413篇
  2000年   386篇
  1999年   266篇
  1998年   105篇
  1996年   92篇
  1995年   92篇
  1992年   209篇
  1991年   215篇
  1990年   202篇
  1989年   201篇
  1988年   205篇
  1987年   183篇
  1986年   172篇
  1985年   172篇
  1984年   158篇
  1983年   114篇
  1982年   114篇
  1979年   149篇
  1978年   94篇
  1977年   95篇
  1976年   91篇
  1975年   138篇
  1974年   157篇
  1973年   181篇
  1972年   155篇
  1971年   141篇
  1970年   124篇
  1969年   133篇
  1968年   176篇
  1967年   132篇
  1966年   141篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
221.
Many behavioral scientists are aware of the advantages of a systematic approach to research and the development of software used in research. However, coordinated and systematic efforts to develop instructional materials in the behavioral sciences are relatively rare. This paper and the symposium of which it is a part describe a systematic effort funded by FIPSE to assess the needs for microcomputer tools and courseware in the undergraduate curriculum in psychology and to stimulate the development of high-quality materials. The conceptual bases for development of materials are vertical and horizontal integration-the development of courseware that spans the curriculum from introductory to advanced, specialized, courses, and the systematic use of materials within a course and across courses and subject areas. The activities of the project, as well as implications for other computer-based development projects, are discussed.  相似文献   
222.
223.
Prior surgical implantation of a venous catheter sensitized rats to coldimmobilization stress. Three of six catheterized females succumbed during the stress. The remaining rats fell into two groups in terms of their core temperature at the end of the stress period: Male uncatheterized rats had higher temperatures than rats in the other three groups. No relation was found between catheter patency and magnitude of hypothermia. Degree of gastric disease paralleled the core temperature findings in that the male uncatheterized rats had significantly fewer gastric erosions than the rats in the other three groups. Additionally, a robust effect of gender was found with uncatheterized females showing more hypothermia and more gastric disease than uncatheterized males. A subsequent experiment was conducted to evaluate whether anesthesia or wearing the protective spring was responsible in part for the sensitization seen. Here, the gender difference was less although females consistently averaged lower core temperatures after stress than did males. Despite similar core temperatures after stress, females that were prepared with the protective spring apparatus developed more gastric disease than female controls or similarly treated males. Thus, the additional sensitization exhibited by females in the first experiment may relate to the fact that both catheterization and the taping procedure were sensitizers while only catheterization was a sensitizer for males.  相似文献   
224.
Full-time employed (N = 255), partly employed (N = 48), and unemployed (N = 43) male and female university graduates completed a questionnaire that included measures designed to assess expected job levels and current job levels and two measures of potential social action (willingness to volunteer actions and hours to a fictional Campaign to Assist Unemployed Youth). Comparisons between groups and the results of multiple regression analyses provided mixed support for the prediction that larger negative gaps between expected and current employment status would be associated with a greater willingness to assist the Campaign. The unemployed respondents tended to volunteer more actions and more hours to the Campaign than did the other two groups. A multiple regression analysis showed that the current level by expected level interaction term was statistically significant as predicted, but only for the fully employed graduates. Within the full-time employed group, female graduates and those from the humanities/social sciences/education schools expressed more willingness to assist the Campaign than did male graduates and those from the sciences/medicine schools of the university. Results were discussed in relation to current research on relative deprivation and reported affect and to recent studies of job satisfaction.  相似文献   
225.
226.
A behavioural programme to treat psychological distress following mastectomy for breast cancer is described. The first 10 patients to be treated were randomly allocated to two treatment groups: Behavioural Programme Only or Behavioural Programme + Drugs (antidepressant medication). Both groups showed improvement over treatment, but the Behavioural Programme + Drugs group appeared to maintain their improvement better.  相似文献   
227.
These experiments investigate whether or not differences in the way that retarded and nonretarded individuals monitor and regulate speed and accuracy of responding contribute to the slower and more variable performance of retarded subjects on choice reaction time (RT) tasks. Rabbitt (1979, 1981) suggested that efficient choice RT performance is mediated by subjects tracking increasingly faster RT bands on successive trials until, by making and recognizing errors, they discover those very fast RT levels that should be avoided and those safe bands, just above typical error levels, that should be tracked. Experiments 1A and 1B established that most retarded subjects detect their errors as efficiently as nonretarded controls, a finding that excludes the possibility that retarded subjects do not monitor accuracy efficiently but achieve comparable levels of accuracy by consistently responding within very slow RT bands that minimize likelihood of errors. Experiment 2 showed that while a qualitatively similar trial-by-trial tracking mechanism mediates the performance of both groups, retarded subjects are less efficient at constraining RTs within very fast, but safe, bands. Increasing error probabilities at longer RTs suggest that momentary fluctuations in stimulus discriminability and/or attention are factors affecting RT variability in retarded subjects. The RT patterns for various sequences of correct responses initiated and terminated by errors suggest that the effective past experience (EPEX) guiding trial-by-trial RT adjustments of retarded subjects is short and inadequate, and it was argued that this can account for much of the remaining RT variability contributing to retarded-nonretarded differences. Not only does a short EPEX increase variability by giving rise to long error-free sequences of slower than average RT but also, when combined with occasional specified random fluctuations, it suggests why retarded subjects can achieve, but not sustain, RT levels maintained by nonretarded subjects.  相似文献   
228.
229.
Periadolescent rats exhibit a number of behavioral differences in comparison with younger or older animals. For instance, periadolescents tend to show enhanced acquisition of simple active avoidance tasks, but impaired acquisition of more complex appetitive and aversive discriminations. In this experiment, rats were trained on a simple passive avoidance task at one of three ages, as weanlings (25 days), periadolescents (35 days), or young adults (45 days). Training occurred in the presence of both a redundant discriminative stimulus and a specified, redundant contextual stimulus. The periadolescents did not differ from either younger or older rats in rate of learning the passive avoidance task. The retention performance of these animals was then tested following a change in either, neither, or both of the redundant cues. When a measure of performance that controls for baseline activity was used, it was observed that periadolescents were not disrupted by a change in the redundant discriminative stimulus, a cue change that clearly disrupted performance in 25- and 45-day-old animals, and tended to be more disrupted by the contextual change than younger or older rats. It is hypothesized that the alterations in performance exhibited by periadolescents may be related to an ontogenetic alteration in stimulus selection modulated by the catecholaminergic systems.  相似文献   
230.
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