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   194405篇
  免费   8407篇
  国内免费   164篇
  202976篇
  2020年   2779篇
  2019年   3439篇
  2018年   3820篇
  2017年   4240篇
  2016年   4793篇
  2015年   3921篇
  2014年   4790篇
  2013年   23412篇
  2012年   5382篇
  2011年   4789篇
  2010年   4209篇
  2009年   4946篇
  2008年   4808篇
  2007年   4475篇
  2006年   4781篇
  2005年   4669篇
  2004年   4179篇
  2003年   3741篇
  2002年   3607篇
  2001年   4284篇
  2000年   4031篇
  1999年   3742篇
  1998年   2931篇
  1997年   2723篇
  1996年   2619篇
  1995年   2472篇
  1994年   2437篇
  1993年   2384篇
  1992年   3074篇
  1991年   2909篇
  1990年   2788篇
  1989年   2657篇
  1988年   2622篇
  1987年   2594篇
  1986年   2589篇
  1985年   2853篇
  1984年   2772篇
  1983年   2538篇
  1982年   2469篇
  1981年   2420篇
  1980年   2264篇
  1979年   2531篇
  1978年   2346篇
  1977年   2253篇
  1976年   2105篇
  1975年   2284篇
  1974年   2362篇
  1973年   2291篇
  1972年   1840篇
  1971年   1752篇
排序方式: 共有10000条查询结果,搜索用时 8 毫秒
911.
In this paper we study the acquisition of German noun plurals in relation to the question of how children represent regular and irregular inflection. Pinker and Prince (1992) have demonstrated several dissociations between regular and irregular inflection in the English past tense system. However, in English, the default status of -ed is confounded with its high frequency; therefore inflectional systems other than English past tense formation must be examined. The noun plural system in German is particularly interesting, because most nouns have irregular plurals in German and the regular (default) plural is less frequent than several of the irregular plurals. Thus it is unclear how a language learner determines whether German even has a regular plural, and if so what form it takes. Based on longitudinal data from impaired and unimpaired monolingual German-speaking children, we find a striking, statistically significant correlation: plural affixes that are used in overregularizations, namely -n or -s, are left out within compounds. This correlation shows that even impaired children are sensitive to the distinction between regular and irregular morphology. We propose a linguistic analysis of the correlation in terms of Kiparsky's (1982, 1985) level-ordering model plus an additional ordering condition on affixes: default (regular) affixes cannot serve as input to compounding processes.  相似文献   
912.
A spreading-activation theory of lemma retrieval in speaking.   总被引:14,自引:0,他引:14  
A Roelofs 《Cognition》1992,42(1-3):107-142
This paper presents a spreading-activation theory of conceptually driven lemma retrieval--the first stage of lexical access in speaking, where lexical items specified with respect to meaning and syntactic properties are activated and selected. The mental lexicon is conceived of as a network consisting of concept, lemma, and word-form nodes and labelled links, with each lexical concept represented as an independent node. A lemma is retrieved by enhancing the activation level of the node representing the to-be-verbalized concept. This activation then spreads towards the lemma level, and the highest activated lemma node is selected. The theory resolves questions such as the hypernym problem (Levelt, 1989). Furthermore, a computer model that implements the theory is shown to be able to account for many basic findings on the time course of object naming, object categorization, and word categorization in the picture-word interference paradigm. In addition, non-trivial predictions regarding the time course of semantic facilitation for hypernyms, hyponyms, and cohyponyms are experimentally tested, and shown to be valid.  相似文献   
913.
At the present, it is unknown how restraint and binge eating/counterregulation are exactly related. Earlier studies on this relationship suffer from two main shortcomings: the studies are all correlational in nature or could not rule out the contribution of confounding variables such as weight loss. The present study investigated whether a break of restraint is a sufficient condition for the occurrence of counterregulation by studying a restrained sample which is not liable to dieting practices and weight loss. The externally imposed restraint on children with regard to eating sweets was broken. However, after breaking their external restraint the children did not counterregulate. It is discussed whether restraint of food intake is really as important for binge eating as it is claimed to be or whether it is merely a consequence or an epiphenomenon of binge eating.  相似文献   
914.
The need for efficient and practical assessment techniques of the multidimensional nature of chronic pain remains paramount in clinical settings. Visual analogue scales (VASs) and simple behavioral observation methods have been proposed as efficient, reliable, and valid measures of the subjective (sensory and affective) and overt behavioral aspects of the pain experience. The relationships among VASs and the UAB Pain Behavior Scale were examined among 48 chronic pain patients. Ratings of overt behavior were significantly related to both the VAS sensory and VAS affective ratings. Regression analysis indicated that the VAS scores accounted for significant amount of the variance (27.7%) in UAB scores. Moreover, the affective dimension of self-reported pain tended to be more strongly related to the visible manifestations of pain than were ratings of pain intensity.  相似文献   
915.
Sigmund Freud, a passionate collector of antiquities, often treated these objects as animate beings. He described such blurring of boundaries between persons and things in the protagonist of W. Jensen's novella, Gradiva. Freud began collecting when his father died, but his unusual attitude toward artefacts was established much earlier, presumably as a consequence of repeated early disappointments in human caretakers. It is postulated that this adaptive maneuver was not simply a displacement of love and hate, but a turning away from vulnerability in relationships, toward attachments over which he might retain effective control. The Freud Collection is largely focused on Greco-Roman and Egyptian objects. Freud's profound interest in classical civilization was established in childhood; he was particularly concerned with the struggle between Aryan Rome and Semitic Carthage, a conflict in which he identified with both sides. This ambivalence reflected growing up within a marginal Jewish family in a Germanic environment. Commitment to classical ideals represented an optimal manner of bridging these contrasting worlds. Egyptian artefacts were, for Freud, links to the prehistory of the Jewish people; they also represent an era when maternal deities found their proper place in man's pantheon--an echo of Freud's prehistoric past.  相似文献   
916.
The debt of neuropsychology to the epilepsies.   总被引:3,自引:0,他引:3  
Both neuropsychology and psychology in general have been enhanced markedly by brain-behavior models derived from the study of the epilepsies. A significant body of neuropsychological concepts originated or were confirmed through epilepsy-based treatment and research. These concepts include the peri-Rolandic homunculus, the role of the hippocampal-temporal lobe complex in cognitive memory, hemisphere plasticity for speech in childhood, the intracarotid amytal procedure for determining hemisphere memory patency, and hemisphere-based models of cognition confirmed through human commissurotomy. Personality and social-emotional research in epilepsy are additional areas in which new conceptual models grounded in psychological science can both repay our debt to the epilepsies and provide much needed psychological research and treatment.  相似文献   
917.
Psychological research is increasingly involved in debates regarding abortion. While recognizing the diversity of ethical and moral issues intertwined with abortion, the American Psychological Association (APA) has focused its involvement on psychological factors, most recently by appointing an expert panel to review the literature on psychological effects. This article notes the history of APA involvement and reports on the panel's conclusions. It presents evidence that abortion is not likely to be followed by severe psychological responses and that psychological aspects can best be understood within a framework of normal stress and coping rather than a model of psychopathology. Correlates of more negative responses following abortion are also discussed.  相似文献   
918.
A biodevelopmental model of insomnia is articulated specifying coordinated nighttime (disturbed sleep pattern) and daytime (no excessive daytime sleepiness) characteristics defining an insomnoid classification in at-risk groups: short sleepers and older adults. Pupillometry is proposed as a useful means of discriminating degree of daytime sleepiness to aid in the differential diagnosis of insomnia and insomnoid states, and the present study tested the discriminative validity of this approach. Noninsomniac (n = 34) and insomniac (n = 29) college students submitted to four 10 min pupillometry sessions tracking daytime sleepiness from morning arising to bedtime. Pupil diameter proved to be an able discriminator of these two groups though substantial overlap of the two distributions was also noted. The results supported the sensitivity of pupillometry in detecting daytime sleepiness, but yielded alternative interpretations. We observed statistical differentiation in insomniac and noninsomniac daytime sleepiness, but substantial, functional overlap between these groups. Assessment and treatment implications arising from the biodevelopmental model were hypothesized.  相似文献   
919.
From a recent theory on the learned nature of craving responses and binge eating, it follows that craving will extinguish when the CS-US bond is broken by prolonged exposure to the cues predicting excessive food intake with response prevention. The present authors treated six obese bulimics with cue exposure and response prevention. Six other patients learned to avoid or escape the binge-related cues with the aid of self control techniques. Although both treatments appeared to be effective in reducing the binge frequency, a most remarkable finding of the present study is that all patients treated by cue exposure were abstinent, directly after treatment and during the 1 yr follow-up. In contrast to the 100% binge-free subjects treated by cue exposure, self control techniques and relapse prevention led to abstinence in merely 33% of the subjects.  相似文献   
920.
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