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   7687篇
  免费   246篇
  国内免费   4篇
  2019年   75篇
  2018年   144篇
  2017年   139篇
  2016年   120篇
  2015年   106篇
  2014年   102篇
  2013年   697篇
  2012年   221篇
  2011年   219篇
  2010年   122篇
  2009年   134篇
  2008年   189篇
  2007年   212篇
  2006年   188篇
  2005年   175篇
  2004年   160篇
  2003年   150篇
  2002年   172篇
  2001年   239篇
  2000年   226篇
  1999年   160篇
  1998年   75篇
  1996年   79篇
  1992年   145篇
  1991年   150篇
  1990年   130篇
  1989年   110篇
  1988年   103篇
  1987年   116篇
  1986年   133篇
  1985年   130篇
  1984年   124篇
  1983年   108篇
  1982年   76篇
  1981年   75篇
  1980年   77篇
  1979年   119篇
  1978年   94篇
  1977年   85篇
  1976年   77篇
  1975年   87篇
  1974年   120篇
  1973年   123篇
  1972年   83篇
  1971年   86篇
  1970年   95篇
  1969年   84篇
  1968年   115篇
  1967年   92篇
  1966年   103篇
排序方式: 共有7937条查询结果,搜索用时 15 毫秒
971.
Why rejection hurts: a common neural alarm system for physical and social pain   总被引:12,自引:0,他引:12  
Numerous languages characterize 'social pain', the feelings resulting from social estrangement, with words typically reserved for describing physical pain ('broken heart', 'broken bones') and perhaps for good reason. It has been suggested that, in mammalian species, the social-attachment system borrowed the computations of the pain system to prevent the potentially harmful consequences of social separation. Mounting evidence from the animal lesion and human neuroimaging literatures suggests that physical and social pain overlap in their underlying neural circuitry and computational processes. We review evidence suggesting that the anterior cingulate cortex plays a key role in the physical-social pain overlap. We also suggest that the physical-social pain circuitry might share components of a broader neural alarm system.  相似文献   
972.
The Minimalist program, a development of earlier work in transformational generative grammar, proposes that the computational system central to human language is a 'perfect' solution to the task of relating sound and meaning. Recent research has investigated the complexities evident in earlier models and attempted to eliminate them, or to show how they are only apparent, following from deeper but simpler properties. Examples of this include the reduction of the number of linguistic levels of representation in the model, and the deduction of constraints on syntactic derivations from general considerations of economy and computational simplicity.  相似文献   
973.
A test visual stimulus is harder to recognize when another stimulus is presented in close temporal vicinity; presenting stimuli in close spatial vicinity of a test stimulus reduces its visibility; presenting a stimulus to one eye can render invisible another stimulus presented to the other eye; and perceiving one interpretation of an ambiguous image prevents the simultaneous perception of other visual interpretations. A single, neurophysiological theory, which may be called 'neural competition' might explain all these phenomena: when two alternative neural visual representations co-exist in the brain, they compete against each other.  相似文献   
974.
Noveck IA 《Cognition》2001,78(2):165-188
A conversational implicature is an inference that consists of attributing to a speaker an implicit meaning that goes beyond the explicit linguistic meaning of an utterance. This paper experimentally investigates scalar implicature, a paradigmatic case of implicature in which a speaker's use of a term like Some indicates that the speaker had reasons not to use a more informative term from the same scale, e.g. All; thus, Some implicates Not all. Pragmatic theorists like Grice would predict that a pragmatic interpretation is determined only after its explicit, logical meaning is incorporated (e.g. where Some means at least one). The present work aims to developmentally examine this prediction by showing how younger, albeit competent, reasoners initially treat a relatively weak term logically before becoming aware of its pragmatic potential. Three experiments are presented. Experiment 1 presents a modal reasoning scenario offering an exhaustive set of conclusions; critical among these is participants' evaluation of a statement expressing Might be x when the context indicates that the stronger Must be x is true. The conversationally-infelicitous Might be x can be understood logically (e.g. as compatible with Must) or pragmatically (as exclusive to Must). Results from 5-, 7-, and 9-year-olds as well as adults revealed that (a) 7-year-olds are the youngest to demonstrate modal competence overall and that (b) 7- and 9-year-olds treat the infelicitous Might logically significantly more often than adults do. Experiment 2 showed how training with the modal task can suspend the implicatures for adults. Experiment 3 provides converging evidence of the developmental pragmatic effect with the French existential quantifier Certains (Some). While linguistically-sophisticated children (8- and 10-year-olds olds) typically treat Certains as compatible with Tous (All), adults are equivocal. These results, which are consistent with unanticipated findings in classic developmental papers, reveal a consistent ordering in which representations of weak scalar terms tend to be treated logically by young competent participants and more pragmatically by older ones. This work is also relevant to the treatment of scalar implicatures in the reasoning literature.  相似文献   
975.
Goals are central to current treatments of work motivation, and goal commitment is a critical construct in understanding the relationship between goals and performance. Inconsistency in the measurement of goal commitment hindered early research in this area but the nine-item, self-report scale developed by Hollenbeck, Williams, and Klein (1989b), and derivatives of that scale, have become the most commonly used measures of goal commitment. Despite this convergence, a few authors, based on small sample studies, have raised questions about the dimensionality of this measure. To address the conflicting recommendations in the literature regarding what items to use in assessing goal commitment, the current study combines the results of 17 independent samples and 2918 subjects to provide a more conclusive assessment by combining meta-analytic and multisample confirmatory factor analytic techniques. This effort reflects the first combined use of these techniques to test a measurement model and allowed for the creation of a database substantially larger than that of previously factor analyzed samples containing these scale items. By mitigating sampling error, the results clarified a number of debated issues that have arisen out of previous small sample factor analyses and revealed a five-item scale that is unidimensional and equivalent across measurement timing, goal origin, and task complexity. It is recommended that this five-item scale be used in future research assessing goal commitment. Copyright 2001 Academic Press.  相似文献   
976.
Previous research has demonstrated electroencephalogram (EEG) changes in response to low-odor concentrations, resulting in near-chance detection. Such findings have been taken as evidence for olfaction without awareness. We replicated and extended previous work by examining EEG responses to water-water control, 0.0001, 0. 001, 0.01, and 1 ppm isoamyl acetate (IAA) in water paired with water only. Detection was above chance (>50%) for.001 and above, and alpha decreased only to those concentrations, suggesting that EEG changes corresponded to IAA awareness. However, when correct trial EEGs were compared to incorrect trial EEGs during.001 ppm, right posterior/central alpha decreased during incorrect trials and alpha decreased more globally (including frontal sites) during correct trials. These data may not reflect awareness or unawareness per se. Instead, results are discussed regarding activation of perceptual systems in the posterior region during incorrect trials and the activation of frontal action systems during a subset of correct trials.  相似文献   
977.
Mitogen-activated protein kinase (MAPK) is abundantly expressed in postmitotic neurons of the developed nervous system. MAPK is activated and required for induction of long-term potentiation (LTP) in the CA1 area of the hippocampus, which is blocked by the specific inhibitor of the MAPK kinase, PD 098059. Recently it was demonstrated that MAPK is activated in the hippocampus after training and is necessary for contextual fear conditioning learning. The present work tests the role of the MAPK cascade in step-down inhibitory avoidance (IA) retention. PD 098059 (50 microM) was bilaterally injected (0.5 microl/side) into the CA1 region of the dorsal hippocampus or entorhinal cortex at 0, 90, 180, or 360 min, or into the amygdala or parietal cortex at 0, 180, or 360 min after IA training in rats using a 0.4-mA foot shock. Retention testing was carried out 24 h after training. PD 098059 impaired retention when injected into the dorsal hippocampus at 180 min, but not 0, 90, and 360 min after training. When infused into the entorhinal cortex, PD 098059 was amnestic at 0 and 180 min, but not at 90 and 360 min after training. The MAPKK inhibitor also impairs IA retention when infused into the parietal cortex immediately after training, but not at 180 or 360 min. Infusions performed into amygdala were amnestic at 180 min, but not at 0 and 360 min after training. Our results suggest a time-dependent involvement of the MAPK cascade in the posttraining memory processing of IA; the time dependency is different in the hippocampus, amygdala, entorhinal cortex, or parietal cortex of rats.  相似文献   
978.
Review   总被引:5,自引:0,他引:5  
  相似文献   
979.
980.
Empirical research and vocational theory indicate that values are important in career counseling and vocational choice. Development of these values is influenced by environmental factors, such as religion. However, there are few empirical investigations of the relation between religious values and career values. The purpose of this study was to investigate the relationship of career values to Christian religious values as they might be assessed in career counseling. Results indicate that there was some overlap between religious and career values, although only for specific extrinsic values.  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