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   34488篇
  免费   1449篇
  国内免费   25篇
  35962篇
  2020年   446篇
  2019年   491篇
  2018年   750篇
  2017年   685篇
  2016年   737篇
  2015年   503篇
  2014年   689篇
  2013年   3001篇
  2012年   1190篇
  2011年   1258篇
  2010年   719篇
  2009年   818篇
  2008年   1118篇
  2007年   1109篇
  2006年   1074篇
  2005年   962篇
  2004年   898篇
  2003年   918篇
  2002年   874篇
  2001年   1025篇
  2000年   1002篇
  1999年   793篇
  1998年   423篇
  1997年   417篇
  1996年   369篇
  1995年   349篇
  1994年   314篇
  1993年   330篇
  1992年   617篇
  1991年   566篇
  1990年   610篇
  1989年   516篇
  1988年   464篇
  1987年   475篇
  1986年   504篇
  1985年   591篇
  1984年   494篇
  1983年   412篇
  1982年   343篇
  1981年   330篇
  1980年   302篇
  1979年   419篇
  1978年   370篇
  1977年   306篇
  1976年   300篇
  1975年   391篇
  1974年   444篇
  1973年   433篇
  1972年   330篇
  1968年   316篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
941.
942.
During the past decade the application of elementary principles of behavior have become a standard in the classroom teacher's repertoire of behavior change strategies. Unfortunately, the application of more advanced principles of behavior derived through basic behavioral research lies as an untapped resource for classroom teachers. Nowhere is this more apparent than in the use of systematic procedures to deliver reinforcers to enhance academic performance. In this paper we provide educators with information on the use of reinforcement schedules in academic settings. Various schedules of reinforcement are presented along with examples of their application in applied settings.  相似文献   
943.
Religious traditions can be drawn on in a number of ways to illuminate discussions of the moral standing of animals and the ethical use of animals in scientific research. I begin with some general comments about relevant points in the history of major religions. I then briefly describe American civil religion, including the cult of health, and its relation to scientific research. Finally, I offer a critique of American civil religion from a Christian perspective.  相似文献   
944.
Functional neuroimaging has been used to investigate neural substrates of mnemonic processes, and cerebral blood flow (CBF) measures have been sensitive to activation with memory tasks. Studies of memory with two-dimensional133Xenon clearance techniques found that word and face recognition tasks produced contralateral CBF changes in mid-temporal cortical regions. This study replicated the activation paradigm, expanding to the three-dimensional resolution of positron emission tomography (PET). Word and face recognition, and a control baseline task were administered to 19 healthy right-handed volunteers (11 men, 8 women) during successive 10 min PET15O-water measures of CBF. Quantitative CBF rates were calculated with the arterial input function and the equilibrium model. Redistributions of blood flow were compared across tasks using both absolute and relative (region/whole brain) CBF.Replicating the133Xenon clearance findings, CBF was “appropriately” lateralized during task performance (left–right for words > left–right for faces) in the mid-temporal region. Contrary to predictions, the recognition tasks did not activate expected mesolimbic or prefrontal areas. The task-induced CBF changes also correlated with performance. Bilateral CBF in mid-temporal and parahippocampal gyrus regions of interest correlated with the ability to correctly identify word targets (sensitivity). Left-lateralized CBF in the amygdala and hippocampus correlated with better word sensitivity as well as specificity (ability to correctly reject foils). Complementally, right-lateralized CBF in the parahippocampal gyrus correlated with better face specificity performance. In addition, left-lateralized CBF in the amygdala and right-lateralized CBF in the parahippocampal gyrus and hippocampus correlated with “mental effort” indices (task performance relative to basal ability) for word and face memory tasks, respectively. Thus, whereas this recognition task showed the expected lateralized increase in the mid-temporal region and not in frontal and limbic areas, lateralized activation in some of these areas was associated with better performance. Exploratory analyses on other regions showed lateralized changes in one additional temporal region, the occipital-temporal, and several limbic regions.  相似文献   
945.
We report the results of a prospective study of a random sample of 1353 elderly but healthy men and women who were followed up for a period of 10 yr, when mortality and cause of death were ascertained. Overall results have been reported elsewhere for mortality from cancer, coronary heart disease and other causes; here we are concerned with the personality factors predicting breast cancer, cervical cancer, cancer of the corpus uteri specifically, as well as other types of cancer in women. Ten specific hypotheses were tested, using specially constructed questionnaires for the purpose, and for most of these statistically significant support was obtained. The results justify belief that specific types of cancer may be related to specific stress/personality factors.  相似文献   
946.
Book reviews     
Socializing Epistemology: The Social Dimensions of Knowledge, Frederick F. Schmitt, Ed., 1994. Lanham, MD, Rowman and Littlefield, ix + 315 pp., US$22.95, ISBN: 0847679594

A Dynamic Systems Approach to the Development of Cognition and Action, Esther Thelen & Linda B. Smith. Cambridge, MA, MIT Press, xxii + 376 pp., $50, ISBN 0–262–20095–3 cloth

From Kant to Hilbert: A Source Book in the Foundations of Mathematics, William B. Ewald, Ed., 1996. Oxford, Oxford University Press. xviii+ 1340 pp., £195.00, two volumes, ISBN 0–19–853271–7 (the set)  相似文献   

947.
948.
This focus section has presented Japanese research on a variety of socialization agents and contexts, including mothering, fathering, peers and multiple-caretakers in families and institutions. The reader is encouraged to compare the papers, discover the theoretical and applied implications of each study for child development in the reader's own culture, and to pursue collaborations with the outstanding young Japanese contributors. We conclude with brief comments on each of the five articles, discussing their limitations, most significant findings, theoretical importance, and implications for subsequent research.  相似文献   
949.
Abstraction Processes in Artificial Grammar Learning   总被引:2,自引:0,他引:2  
Four experiments explored the extent to which abstract knowledge may underlie subjects' performance when asked to judge the grammaticality of letter strings generated from an artificial grammar. In Experiments 1 and 2 subjects studied grammatical strings instantiated with one set of letters and were then tested on grammatical and ungrammatical strings formed either from the same or a changedletter-set.Evenwith a change ofletter-set, subjects were found to be sensitive to a variety of violations of the grammar. In Experiments 3 and 4, the critical manipulation involved the way in which the training strings were studied: an incidental learning procedure was used for some subjects, and others engaged in an explicit code-breaking task to try to learn the rules of the grammar. When strings were generated from a biconditional (Experiment 4) but not from a standard finite-state grammar (Experiment 3), grammaticality judgements for test strings were independent of their surface similarity to specific studied strings. Overall, the results suggest that transfer in this simple memory task is mediated at least to some extent by abstract knowledge.  相似文献   
950.
Escalating pressures for self-development require people of all ages to possess increasingly sophisticated levels of self-knowledge. From a career planning perspective, this means knowing more about one's strengths and weaknesses. Although some people acquire knowledge about themselves from instruments and assessment processes, many more look to their personal histories, including career histories, for evidence confirming competence. Research examining failures and setbacks recalled by a diverse sample of artists, athletes and business people is reported. It is concluded that people often hold distorted interpretations of life's disappointments, underscoring the need for informed guidance  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