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   25226篇
  免费   1063篇
  国内免费   19篇
  2023年   136篇
  2021年   230篇
  2020年   423篇
  2019年   508篇
  2018年   669篇
  2017年   642篇
  2016年   734篇
  2015年   500篇
  2014年   670篇
  2013年   2777篇
  2012年   1136篇
  2011年   1188篇
  2010年   788篇
  2009年   823篇
  2008年   1122篇
  2007年   1091篇
  2006年   1055篇
  2005年   930篇
  2004年   927篇
  2003年   910篇
  2002年   883篇
  2001年   418篇
  2000年   409篇
  1999年   397篇
  1998年   377篇
  1997年   361篇
  1996年   291篇
  1995年   306篇
  1994年   291篇
  1993年   275篇
  1992年   261篇
  1991年   257篇
  1990年   239篇
  1989年   218篇
  1988年   193篇
  1987年   213篇
  1986年   209篇
  1985年   256篇
  1984年   268篇
  1983年   231篇
  1982年   234篇
  1981年   256篇
  1980年   225篇
  1979年   209篇
  1978年   222篇
  1977年   195篇
  1976年   197篇
  1975年   158篇
  1974年   180篇
  1973年   140篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
211.
Michael Washburn 《Zygon》1987,22(1):67-85
Abstract. Five types of psychic duality are distinguished: bipolarity, bimodality, contrariety, dualism, and the coincidentia op–positorurn. Bipolarity is the basic division of the psyche into egoic and nonegoic (physico–dynamic) poles. Bimodality is the division of egoic functioning into active and receptive modes. Contrariety is the division of the nonegoic sphere into opposing sympathetic and parasympathetic systems. Dualism is the organization imposed upon the bipolar structure by primal repression. And the coincidentia opositorum is the condition of psychic integration that would emerge were dualism to be transcended and the bipolar structure (together with the bimodal and contrarietal structures) unified into a higher whole.  相似文献   
212.
With a sample of 18 capital cases tried in Kentucky, South Carolina, and California, we attempted to replicate an earlier study which showed that significantly more defense challenges for cause were granted under conditions of sequestered, individual voir dire than when voir dire was conducted under less enhanced conditions. In the current sample, sequestered, individual voir dire again resulted in more defense removals for cause than obtained with less extensive voir dire. We present data on the defense removals for cause partitioned into five categories according to the reason for the challenge and analyze the effects of jury selection consultants on the various indices of voir dire as well as final sentence.  相似文献   
213.
A general latent variable model is given which includes the specification of a missing data mechanism. This framework allows for an elucidating discussion of existing general multivariate theory bearing on maximum likelihood estimation with missing data. Here, missing completely at random is not a prerequisite for unbiased estimation in large samples, as when using the traditional listwise or pairwise present data approaches. The theory is connected with old and new results in the area of selection and factorial invariance. It is pointed out that in many applications, maximum likelihood estimation with missing data may be carried out by existing structural equation modeling software, such as LISREL and LISCOMP. Several sets of artifical data are generated within the general model framework. The proposed estimator is compared to the two traditional ones and found superior.The research of the first author was supported by grant No. SES-8312583 from the National Science Foundation and by a Spencer Foundation grant. We wish to thank Chuen-Rong Chan for drawing the path diagram.  相似文献   
214.
Two experiments investigated the modulation of event-related potentials (ERPs) by semantic priming and item repetition. In Experiment 1, subjects silently counted occasional non-words against a background of words, a proportion of which were either semantic associates or repetitions of a preceding word. Compared to control items, ERPs to repeated words were distinguished by an early (ca. 200 msec) transient negative-going deflection and a later, topographically widespread and temporally sustained positive-going shift. In contrast, semantically primed words showed a relatively small, topographically and temporally limited positive-going modulation peaking around 500 msec. These data were interpreted as evidence against models of priming and repetition which postulate similar loci for these effects. In Experiment 2, subjects counted occasional words against a background of non-words, some of which were repeated. ERPs to repetitions showed a similar early ERP modulation to that in Experiment 1, and also displayed a later slow positive shift. This latter effect was smaller in magnitude and had a delayed onset in comparison to Experiment 1. It was concluded that the effects of repetition differ as a consequence of whether, prior to their first presentation, items possess a representation in lexical memory.  相似文献   
215.
The term pioneer is used for girls aspiring to male-dominated careers. This longitudinal study assesses the career choices of 68 middle-class girls during childhood (8–13 years, Phase I) and again during adolescence (13–18 years, Phase II), and investigates the relation between pioneering career choice and personal and family characteristics. Subjects were originally selected for exposure vs nonexposure to exogenous hormones during pregnancy. In childhood, pioneers were somewhat older, were more often persistent tomboys, had higher IQs, and had parents with higher educational attainment. In adolescence, paternal education was the only variable that showed the same relation to career choice. Adolescent girls who had wanted to get married at the time of the childhood assessment were now less likely to choose pioneering careers. Adolescent pioneers also had higher educational aspirations than nonpioneers and less likely anticipated being married within ten years than nonpioneers. A number of statistically borderline relationships were also observed: pioneers had somewhat fewer older brothers than nonpioneers, less often came from homes in which traditional femininity was stressed, and more frequently had mothers who had worked outside the home throughout their daughters' school years than mothers of nonpioneers. Prenatal exposure to exogenous sex hormones was not related to career choice during either childhood or adolescence.  相似文献   
216.
217.
The purpose of this study was to examine the relationship of four client characteristics—functioning level, aggressive behavior, self-injurious behavior, and attractiveness—with staff expectations of and frustration with clients. Forty staff members who worked with severely and profoundly retarded individuals served as participants. Staff members rated each client with whom they worked on the extent to which the client could behave better and learn faster as well as the level of frustration experienced in working with the client. A client's functioning level was related to staff perceptions such that the higher the functioning level, the more the client was seen as having the potential to behave better or learn faster than (s)he was presently demonstrating. Staff frustration was related to client aggression indicating that as aggression increased so did staff frustration in working with that client. Implications of the results are discussed.  相似文献   
218.
219.
Effects of smoking on spontaneous bilateral skin conductance were studied as a consequence of interactions with set and setting. Bilateral skin conductance was recorded in six men and six women who smoked and an equal number of nonsmokers on two different days. On the first day, spontaneous electrodermal activity was recorded before and after a 10-minute rest period during which half the smokers smoked a cigarette. On the second day, one week later, spontaneous activity was again recorded before and after a 10-minute rest period during which the remaining smokers smoked a cigarette. Nonsmokers did not smoke at any time. Following smoking there was a significant negative correlation between a preference for visual over nonvisual imagery and spontaneous skin conductance responsivity in the left as compared to the right hand. Correlations were significantly different in smokers and nonsmokers. Smokers showed significantly greater preferences for either visual or nonvisual imagery than nonsmokers. Nonresponding nonsmokers were higher on the psychoticism (P) scale of the Eysenck Personality Questionnaire (EPQ) than responding nonsmokers. Smokers scored higher on P than nonsmokers. Interactions between personality, cognitive style, and the experimental situation, set, and setting were discussed in relation to the arousing effects of nicotine.  相似文献   
220.
A suite of programs is described for simulating the Rescorla-Wagner (1972) model of associative learning, the Solomon and Corbit (1974) opponent-process theory, and Schull’s (1979) extension of the latter. The programs are written for the Commodore 64 computer.  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