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   37074篇
  免费   1349篇
  国内免费   11篇
  2018年   569篇
  2017年   511篇
  2016年   605篇
  2015年   432篇
  2014年   516篇
  2013年   3511篇
  2012年   884篇
  2011年   916篇
  2010年   594篇
  2009年   576篇
  2008年   889篇
  2007年   794篇
  2006年   740篇
  2005年   638篇
  2004年   610篇
  2003年   638篇
  2002年   598篇
  2001年   1195篇
  2000年   1134篇
  1999年   870篇
  1998年   391篇
  1996年   505篇
  1995年   479篇
  1994年   466篇
  1993年   440篇
  1992年   906篇
  1991年   815篇
  1990年   814篇
  1989年   718篇
  1988年   716篇
  1987年   704篇
  1986年   704篇
  1985年   684篇
  1984年   607篇
  1983年   508篇
  1982年   413篇
  1981年   418篇
  1979年   578篇
  1978年   440篇
  1976年   395篇
  1975年   535篇
  1974年   529篇
  1973年   595篇
  1972年   567篇
  1971年   501篇
  1970年   447篇
  1969年   432篇
  1968年   547篇
  1967年   461篇
  1966年   445篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
931.
The question of left hemisphere dysfunction in infantile autism   总被引:3,自引:0,他引:3  
  相似文献   
932.
Is there a cell-biological alphabet for simple forms of learning?   总被引:5,自引:0,他引:5  
  相似文献   
933.
This paper proposes test statistics based on the likelihood ratio principle for testing equality of proportions in correlated data with additional incomplete samples. Powers of these tests are compared through Monte Carlo simulation with those of tests proposed recently by Ekbohm (based on an unbiased estimator) and Campbell (based on a Pearson-Chi-squared type statistic). Even though tests based on the maximum likelihood principle are theoretically expected to be superior to others, at least asymptotically, results from our simulations show that the gain in power could only be slight.  相似文献   
934.
The effects of tobacco smoking on responses to electrical stimulation were studied according to a Method of Limits (ML) threshold analysis and a Sensory Decision Theory (SDT) analysis. For the ML procedure, Detection Threshold (DT), Pain Threshold (PT) and Tolerance Level (TL) measures were obtained. For the SDT procedure, nonparametric estimates of capacity to discriminate between stimulus intensities (P(A)) and response criterion (B) were calculated. There was no main effect of tobacco smoking on responses to electrical stimulation. Males had consistently higher ML thresholds than females in both the NS and S condition. Males also tended to increase in DT and PT after smoking. From a comparison between the effects of smoking on ML and SDT measures it was suggested that PT is related mainly to sensory factors and TL to response factors.  相似文献   
935.
Asymmetric neural control systems in human self-regulation   总被引:15,自引:0,他引:15  
  相似文献   
936.
The paper contains a detailed study of the St. Pauls' riots of April 1980. Particular attention is paid to the limits of participation in the event and the limits of crowd action. It is argued that these limits show clear social form and cannot be explained in terms of the individualistic theories that dominate crowd psychology. Instead a model of crowd behaviour based on the social identity model is advanced to account for the observations. It is concluded that crowd behaviour is more sophisticated and creative than hitherto allowed and that the neglect of this field should be remedied.  相似文献   
937.
This commentary critically examines two facets of Tracy Llanera's recent book Richard Rorty: Outgrowing Modern Nihilism. First, it considers her interpretation of Richard Rorty's redemptive project. It argues that, while Llanera succeeds in resolving tensions in Rorty's public-private distinction, her account downplays the role of abnormal discourse within projects of self-creation. Second, it raises several questions about Llanera's strategy for situating this redemptive project within debates concerning existential nihilism. On her view, one ought to follow Rorty in addressing the problem of egotism instead of the problem of nihilism, since the former is prior to the latter. But it is not clear who counts as an egotist, or why egotists are especially prone to becoming nihilists. Moreover, there are reasons to think that egotism and nihilism are fundamentally different kinds of problems.  相似文献   
938.
The reinforcer pathology model posits that core behavioral economic mechanisms, including delay discounting and behavioral economic demand, underlie adverse health decisions and related clinical disorders. Extensions beyond substance use disorder and obesity, however, are limited. Using a reinforcer pathology framework, this study evaluates medical adherence decisions in patients with multiple sclerosis. Participants completed behavioral economic measures, including delay discounting, probability discounting, and a medication purchase task. A medical decision-making task was also used to evaluate how sensitivity to mild side effect risk and efficacy contributed to the likelihood of taking a hypothetical disease-modifying therapy. Less steep delay discounting and more intense (greater) medication demand were independently associated with greater adherence to the medication decision-making procedure. More generally, the pattern of interrelations between the medication-specific and general behavioral economic metrics was consistent with and contributes to the reinforcer pathology model. Additional research is warranted to expand these models to different populations and health behaviors, including those of a positive health orientation (i.e., medication adherence).  相似文献   
939.
Western scholarship has underlined the relevance of social identity, perceived efficacy, emotions, and cost–benefit assessments as central catalysts of collective action. Little has been done to understand the context-sensitivity of these catalysts by means of cross-culturally comparative designs. The current study explores their context-sensitivity. It aims to find out whether existing opportunity structures in a democratic, nonrepressive country like Germany produce catalysts of collective action different from those produced in an autocratic, repressive country like Turkey. It also aims to understand the role of social media in mobilizing people in these two contexts. Semistandardized interviews with activists were carried out in both countries (n = 18 in Germany and n = 15 in Turkey) and analyzed by means of a cross-culturally comparative inductive coding procedure including initial and focused coding. Results show that collective action is related to different configurations of collective-action catalysts in the two countries. Solidarity concerns at the face of existential risks are more pronounced in Turkey, whereas political-change concerns are more important in Germany. The role of social media accordingly differs, adhering to the different activist goals. Theoretical implications for the role of context in studying collective action are discussed.  相似文献   
940.
This review involved a systematic analysis of equivalence-based instruction (EBI) that aimed to improve food-size interventions in diverse populations. Systematic searches identified seven studies published since 2010 that met inclusion criteria. These studies were analyzed according to their participants, design, setting, content taught, training structures, training protocol, testing format, treatment integrity, and outcomes. Results showed EBI procedures for teaching food estimation skills have been mostly implemented with adults. The type of content taught in the identified studies included carbohydrate ranges, portion size with food and non-food items, measuring cups and nutritional content of calories. Majority of included studies used one-to-many training structure and simultaneous protocols for teaching stimulus relations. Five studies completed a generalization probe and three studies reported treatment integrity data. Overall, all participants demonstrated skill acquisition of novel relations between food and portion measurement aides. Recommendations for future research and clinical applications of EBI in teaching food portion estimation are presented.  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