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   30494篇
  免费   465篇
  国内免费   5篇
  2021年   88篇
  2020年   149篇
  2019年   206篇
  2018年   3715篇
  2017年   3025篇
  2016年   2473篇
  2015年   381篇
  2014年   309篇
  2013年   1048篇
  2012年   931篇
  2011年   2796篇
  2010年   2758篇
  2009年   1699篇
  2008年   2008篇
  2007年   2478篇
  2006年   301篇
  2005年   437篇
  2004年   389篇
  2003年   322篇
  2002年   289篇
  2001年   328篇
  2000年   327篇
  1999年   235篇
  1998年   117篇
  1997年   99篇
  1996年   99篇
  1993年   87篇
  1992年   162篇
  1991年   163篇
  1990年   159篇
  1989年   140篇
  1988年   125篇
  1987年   131篇
  1986年   144篇
  1985年   146篇
  1984年   132篇
  1983年   104篇
  1982年   91篇
  1981年   89篇
  1979年   147篇
  1976年   90篇
  1975年   110篇
  1974年   135篇
  1973年   118篇
  1972年   104篇
  1971年   100篇
  1970年   112篇
  1969年   106篇
  1968年   108篇
  1967年   129篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
131.
There are two phases in the process of negotiating for peace with antagonistic national groups. The leader (or leaders) of one such group will not negotiate with his opposite number until political foundations to support such negotiation are laid down, and obstacles to peace identified and dealt with; at least some measure of success is anticipated by both sides. Accordingly, the first phase requires the building of bridges between those representing opposing nations. The activities in this preliminary phase are sometimes called Track II diplomacy; they differ from those of official or Track I diplomacy. I suggest two kinds of concepts that may be useful in Track II diplomacy, and present them in the hope of initiating further discussion, and exploration of metapsychological underpinnings of each concept. As Mitscherlich (1971) suggested, the psychology of international politics may be better understood if psychoanalysts are willing to engage in interdisciplinary work with others engaged in such endeavors.  相似文献   
132.
Work values and key influencers of a sample of black male and female adolescents were examined. Results indicated that boys and girls valued both the intrinsic and extrinsic rewards of work; however, girls reported slighter stronger extrinsic values than did boys. In addition, the sexes reported differences in the importance of specific work values such as "making lots of money," and "doing important things." When naming a key influencer, respondents tended to cite a same-sex and race individual. Sex of one's key influencer was related to certain work values, with subjects reporting a male key influencer valuing "trying out one's own ideas" and "having a secure future" more than those reporting a female key influencer. The interaction of sex of subject and sex of key influencer was significant on one of the work value outcomes. Implications of these findings are considered.  相似文献   
133.
The present study investigated effects of age and instructions on temporal regulations of behavior in children. In the first experiment 4 1/2-year-old and 7-year-old subjects were trained with a DRL (differential reinforcement of low rates) 5-s and a DRL 10-s schedule. Results demonstrate that age and timing performance are related. Seven-year-olds are more efficient than the 4 1/2-year-olds. A striking decline in the 4 1/2-year-old children's capacity to space responses was observed in the DRL 10-s schedule as compared to the DRL 5-s schedule. Analysis of individual performances suggests that the evolution of DRL performance between 4 and 7 years of age depends not only on the development of the capacity to delay responding but also on the acquisition of the ability to represent the reinforcement contingencies, that is, the temporal parameters of the task to oneself. In order to test this hypothesis a second experiment was conducted where instructions to wait between operant responses were given to a group of 4 1/2-year-old subjects at the beginning of a DRL 5-s and a DRL 10-s schedule. The results show that these instructions enhance DRL performance. By directing the 4 1/2-year-old subjects' attention to the temporal requirements of the task, instructions led to efficient performance and accurate timing of responses to the DRL schedule.  相似文献   
134.
Court cases since the classic Brito v. Zia (1973) decision dealing with terminations based on subjective performance appraisals are reviewed. Professional interpretations of Brito v. Zia are also examined and criticized in light of professional practice and subsequent court decisions. Major themes and issues are distilled from the review of cases, and implications and recommendations for personnel practices were discussed.  相似文献   
135.
136.
Yugoslav agrammatic Broca's aphasics, fluent anomics, and control subjects were tested for comprehension of agent-object relations in a series of simple Serbo-Croatian sentences in the conversational past tense, consisting of two nouns and a transitive action verb. The availability of two closed class cues--case contrasts and gender contrasts--as well as the availability of an open class lexical cue--animacy contrasts--was varied across sentences. An analysis of subjects' agent-object assignments yielded the following results: Both Broca's aphasics and fluent anomics showed a selective impairment in sensitivity to closed class morphology, although anomics were considerably less impaired than Broca's aphasics. This finding was interpreted as evidence for a non-syndrome-dependent vulnerability of abilities to process closed class morphology for comprehension. In addition, the pattern of agent-object assignments for Broca's aphasics revealed that the degree to which they were able to access the two closed class cues depended on a convergence of the various cues to agent-object relations. In particular, a convergence of case and gender contrasts had an interactive effect on Broca's responses: Gender agreement cues were accessed only in the presence of convergent case contrasts. Conversely, sensitivity to case contrasts was dramatically heightened in the presence of convergent gender contrasts. These results were consistent with a view that the two cues function as intrasentential "primes" or "retrieval cues" for one another.  相似文献   
137.
One of the possible adaptive costs of coping with stress is diminished capacity to respond to subsequent adaptive demands. This paper examined the complex interplay between major life events and one source of chronic strain. Residents of the greater Los Angeles metropolitan area exposed to higher levels of smog, who had also experienced a recent stressful life event, exhibited poorer mental health than those exposed to pollution who had not experienced a recent stressful life event. There were, however, no direct effects of smog levels on mental health. These patterns of results were replicated in both a cross-sectional and a longitudinal study. The interplay of psychosocial vulnerability and environmental conditions is discussed.  相似文献   
138.
This study evaluated the clinical validity of the Intellectual Screening, Development, and Achievement scales of the Personality Inventory for Children-Revised (PIC-R), as well as the newly derived PIC-R Factor IV scale, in identifying cognitive impairment in a clinic-referred sample of preschoolers. The clinical validity of these PIC-R subscales was also compared to that of the Minnesota Child Development Inventory (MCDI). The results showed that the PIC-R scales and Factor IV were reasonably successful in identifying cognitively impaired preschoolers, but much less successful in identifying cognitively normal preschoolers. Overall, the MCDI was the most successful in correctly identifying the preschoolers' cognitive status.  相似文献   
139.
A long-term temporal component of working memory of rats trained on the radial maze has been shown to be susceptible to disruption by the protein synthesis inhibitor, anisomycin. It is not clear whether protein synthesis played a role in working memory because accurate performance on the radial maze required the storage of a large amount of information, or because the information was to be held in store for relatively long periods of time. This experiment tested these hypotheses by assessing the effect of anisomycin on choice accuracy in a comparatively simple spatial delayed alternation task. Results indicate that under the present training conditions, protein involvement in working memory is related more to the length of the retention interval than to the amount of information retained.  相似文献   
140.
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