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   38939篇
  免费   1505篇
  国内免费   16篇
  40460篇
  2020年   452篇
  2019年   560篇
  2018年   761篇
  2017年   825篇
  2016年   844篇
  2015年   592篇
  2014年   720篇
  2013年   3091篇
  2012年   1307篇
  2011年   1313篇
  2010年   862篇
  2009年   815篇
  2008年   1180篇
  2007年   1203篇
  2006年   1064篇
  2005年   952篇
  2004年   897篇
  2003年   843篇
  2002年   861篇
  2001年   1190篇
  2000年   1133篇
  1999年   886篇
  1998年   402篇
  1997年   396篇
  1996年   366篇
  1995年   373篇
  1994年   361篇
  1993年   366篇
  1992年   749篇
  1991年   657篇
  1990年   720篇
  1989年   630篇
  1988年   662篇
  1987年   608篇
  1986年   617篇
  1985年   557篇
  1984年   521篇
  1983年   495篇
  1982年   366篇
  1979年   574篇
  1978年   416篇
  1975年   463篇
  1974年   496篇
  1973年   537篇
  1972年   401篇
  1971年   391篇
  1969年   400篇
  1968年   474篇
  1967年   434篇
  1966年   354篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
951.
The effects of distractor clustering on target detection were examined in two experiments in which subjects attended to binaural tone bursts of one frequency while ignoring distracting tones of two competing frequencies. The subjects pressed a button in response to occasional target tones of longer duration (Experiment 1) or increased loudness (Experiment 2). In evenly spaced conditions, attended and distractor frequencies differed by 6 and 12 semitones, respectively (e.g., 2096-Hz targets vs. 1482- and 1048-Hz distractors). In clustered conditions, distractor frequencies were grouped; attended tones differed from the distractors by 6 and 7 semitones, respectively (e.g., 2096-Hz targets vs. 1482- and 1400-Hz distractors). The tones were presented in randomized sequences at fixed or random stimulus onset asynchronies (SOAs). In both experiments, clustering of the unattended frequencies improved the detectability of targets and speeded target reaction times, Similar effects were found at fixed and variable SO As. Results from the analysis of stimulus sequence suggest that clustering improved performance primarily by reducing the interference caused by distractors that immediately preceded the target.  相似文献   
952.
Two experiments compared rates of solving simple and complex addition and multiplication problems in groups of speakers of French or English in Experiment 1 (n = 35) and Spanish or English in Experiment 2 (n = 84). Subjects were divided into groups of English unilinguals, weak bilinguals, and strong bilinguals according to their performance on a naming task. In both experiments, simple problems consisted of two single-digit numbers. At least three single-digit numbers were used for complex problems in Experiment 1 and double-digit numbers in Experiment 2. Mean solution times, particularly for complex problems, were lowest for the monolingual group, followed in turn by the weak bilingual and strong bilingual groups, but these differences were not statistically reliable in either experiment. In Experiment 2, however, componential analyses of solution times indicated that strong bilingual subjects were slower at executing the carry operation when solving complex problems, relative to the two remaining groups. Results were interpreted in terms of the relationship between bilingualism and the representation and processing of numerical information.  相似文献   
953.
When a deaf child is born to hearing parents, a grieving process is initiated in the parents. Unresolved grieving over their child's deafness often makes it difficult for hearing parents to accept the importance of signing, thus increasing the child's problems — further source of grief for these parents. Clinical illustrations are provided of (1) the reciprocal relationship between disruption of the mourning process and disturbance of communication between family members, and (2) the transmission of the dysfunctional relationship between hearing parents and deaf children to the subsequent relationship between the deaf children, when they reach adulthood, and their hearing children.  相似文献   
954.
955.
956.
Paradigmatic complexes in family psychotherapy have been indicating a revolutionary change and the creation of new paradigms for the past thirty years. Starting with the application of the general systems theory and the development of those concepts that have been emerging regarding psychosomatic illnesses we discuss the epistemological confusion created, the methodological problems and the dissociation between theory and practice. We suggest a double process of investigation of the family structure using a knowledge of the basic attitudes and the development of a psychotherapy programme within the family of the psychosomatic patient.  相似文献   
957.
958.
ABSTRACT Previous research has indicated that extraversion and neuroticism are substantially affected both by genotype and environment. This study assesses genetic and environmental influences on the other three components of the five-factor model of personality: Openness to Experience, Agreeableness, and Conscientiousness. An abbreviated version of the NEO Personality Inventory (NEO-PI) was administered to 82 pairs of identical twins and 171 pairs of fraternal twins reared apart and 132 pairs of identical twins and 167 pairs of fraternal twins reared together. Estimates of genetic and environmental effects for Openness and Conscientiousness were similar to those found in other studies of personality: Genetic influence was substantial and there was little evidence of shared rearing environment. Results for Agreeableness were different: Genetic influence accounted for only 12% of the variance and shared rearing environment accounted for 21% of the variance. Few significant gender or age differences for genetic and environmental parameters were found in model-fitting analyses.  相似文献   
959.
The authors report a study that suggests the career paths of workers on short-term federal projects may be enhanced as a result of developing a relationship with a mentor through such projects.  相似文献   
960.
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