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   25295篇
  免费   306篇
  国内免费   2篇
  2024年   11篇
  2023年   79篇
  2022年   95篇
  2021年   120篇
  2020年   171篇
  2019年   195篇
  2018年   3699篇
  2017年   3054篇
  2016年   2460篇
  2015年   334篇
  2014年   241篇
  2013年   746篇
  2012年   931篇
  2011年   2713篇
  2010年   2709篇
  2009年   1583篇
  2008年   1990篇
  2007年   2382篇
  2006年   283篇
  2005年   386篇
  2004年   300篇
  2003年   220篇
  2002年   160篇
  2001年   77篇
  2000年   121篇
  1999年   69篇
  1998年   45篇
  1997年   49篇
  1996年   30篇
  1995年   14篇
  1994年   25篇
  1993年   18篇
  1992年   25篇
  1991年   23篇
  1990年   35篇
  1989年   23篇
  1988年   15篇
  1987年   20篇
  1986年   9篇
  1985年   16篇
  1984年   6篇
  1983年   8篇
  1982年   8篇
  1981年   15篇
  1980年   6篇
  1979年   6篇
  1978年   7篇
  1974年   10篇
  1972年   7篇
  1965年   6篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
Tested a theoretical model on the effects of social role identity, illness intrusion, and competence on psychological well-being among 109 low-income Latinas with arthritis. All six roles studied were rated as highly important identities. Sex-role nontraditionalism was associated with less importance of the homemaker, mother, and grandmother roles. Negative affect increased as a function of intrusions into valued identities. Having important role identities contributed to feelings of competence (i.e., self-esteem and self-efficacy), which in turn, contributed to psychological well-being. Competence also mediated the effects of pain, identity, and illness intrusions on psychological well-being. Results suggest competence processes play an important role in well-being.  相似文献   
72.
The etiology of the observed relationship between general cognitive ability and reading performance was investigated by analyzing data from samples of twin pairs tested in the Colorado Learning Disabilities Research Center. Bivariate phenotypic and genetic structural equation models were fitted to data from 486 twin pairs selected for reading deficits (276 identical and 210 same-sex fraternal) and 314 control pairs (195 identical and 119 same-sex fraternal). Subtests of the Peabody Individual Achievement test (Reading Recognition, Reading Comprehension, and Spelling) were used as measures of reading performance, and verbal and performance IQ scores from the Wechsler Intelligence Scale for Children-Revised (WISC-R) or Wechsler Adult Intelligence Scale-Revised (WAIS-R) were used as indices of general cognitive ability. The results of these confirmatory factor analyses indicate that shared environmental influences do not contribute significantly to covariation between general cognitive ability and reading performance. In contrast, genetic influences contribute substantially to the relationship between the two latent factors. Moreover, the genetic and phenotypic variances of reading performance in the proband group are larger than those in controls, whereas both the genetic and phenotypic correlations between reading performance and general cognitive ability are lower in probands. These results are consistent with recent reports that reading disability may be caused by one or more genes with major effects.  相似文献   
73.
74.
How can we explain that an assertion on something perceived can be understood in the same manner by somebody who cannot perceive that scene? This problem bases the interest in computational linguistics in how listener modeling could possibly be harmonized with reference semantics. Mental images substituting real perception appear as a way out. The architecture of the listener model has to be adapted to the creation and use of such pictorial data structures. Furthermore, the relation between the latter and a verbal (i. e., propositional) representation must be understood. The resulting architecture of a listener model with reference semantics can be employed to solve communicational problems from three general classes in a better way, as is demonstrated by an example implementation.  相似文献   
75.
This article presents research in which the Five Factor Model of personality was tested as a predictor of job performance. 125 financial services managers who had enrolled in a potential evaluation programme were given the NEO-FFI, a questionnaire designed for measuring the Big Five. Job performance was assessed using nine rating scales and they were grouped into two components: job problem-solving ability and job motivation. Also, one single scale for measuring global job performance was used. The results show that Neuroticism and Conscientiousness correlated with the two components and with the global measure of job performance. Extraversion, Openness and Agreeableness are correlated with one facet or with the global rating of job performance. Taken together, the results suggest that the Five Factor Model is a valid predictor of job performance. The implications of the results for practice and future research are discussed.  相似文献   
76.
Most concepts of development explain certain behavior changes as products or markers of the invariable succession of emerging periods, stages, refinements, or achievements that define and order much of an individual's life. A different but comparable concept can be derived from the most basic mechanisms of behavior analysis, which are its environmental contingencies, and from its most basic strategy, which is to study behavior as its subject matter. From a behavior-analytic perspective, the most fundamental developmental questions are (a) whether these contingencies vary in any systematic way across the life span, and thus make behavior change in a correspondingly systematic way; and (b) whether some of these contingencies and their changes have more far-reaching consequences than others, in terms of the importance to the organism and others, of the behavior classes they change. Certain behavior changes open the door to especially broad or especially important further behavior change, leading to the concept of the behavioral cusp. A behavioral cusp, then, is any behavior change that brings the organism's behavior into contact with new contingencies that have even more far-reaching consequences. Of all the environmental contingencies that change or maintain behavior, those that accomplish cusps are developmental. Behavior change remains the fundamental phenomenon of development for a behavior-analytic view; a cusp is a special instance of behavior change, a change crucial to what can come next.  相似文献   
77.
Food-deprived rats (at 80% of their free-feeding weights) were exposed to a fixed-time 60-s schedule of food-pellet presentation and developed schedule-induced drinking. Lick-dependent signaled delays (10 s) to food presentation led to decreased drinking, which recovered when the signaled delays were discontinued. A major effect of this punishment contingency was to increase the proportion of interpellet intervals without any licks. The drinking of yoked control rats, which received food at the same times as those exposed to the signaled delay contingency (masters), was not consistently reduced. When food-deprivation level was changed to 90%, all master and yoked control rats showed decreases in punished or unpunished schedule-induced drinking. When the body weights were reduced to 70%, most master rats increased punished behavior to levels similar to those of unpunished drinking. This effect was not observed for yoked controls. Therefore, body-weight loss increased the resistance of schedule-induced drinking to reductions by punishment. Food-deprivation effects on punished schedule-induced drinking are similar to their effects on food-maintained lever pressing. This dependency of punishment on food-deprivation level supports the view that schedule-induced drinking can be modified by the same variables that affect operant behavior in general.  相似文献   
78.
The control of the ground reaction force vector relative to the center of gravity (CoG) was examined while subjects performed a back-lifting task. Six male subjects (aged 24.0 +/- 2.5 years) repeatedly lifted a barbell. A biomechanical analysis that used a linked segment model revealed that the summed rotations of body segments during lifting yielded a specific rate of change of the angular momentum of the entire body. This equaled the external moment provided by Fsubg; relative to CoG. This implies that multisegment movements involve control of the angular momentum of the entire body through an appropriately directed Fsubg;. Thus, in dynamic tasks Fsubg; is pointed away from rather than lined up with the CoG, as is the case in static tasks.  相似文献   
79.
Methodological difficulties are identified in the assessment of children's comprehension of relative clauses (RCs) by means of the standard acting-out procedure. An alternative experimental task is proposed which attempts to minimize these difficulties while exploring the advantages of the acting-out technique. An experiment is reported in which Portuguese-speaking 3- to 6-year olds were tested by means of this alternative task. The results show children being affected by both the position and the focus of the RC in the same way adults have been reported to be and an error analysis suggests that most of children's difficulties can be ascribed to memory overload while RCs are processed as noun modifier sentences. These results contradict the view that there are developmental differences with regard to the way sentences with RCs are parsed and that processing load induces errors particularly manifested in right-branching subject focus sentences. Developmental changes taking place between the ages of 3 and 6 are considered and questions are raised concerning development from the age of 5.The research reported here was carried out while the author read for the PhD degree at the University of London. The writing up of this paper was financially supported by a postdoctoral grant from the Brazilian Research Council (CNPq: 302103-86.4).  相似文献   
80.
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