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   19684篇
  免费   797篇
  国内免费   7篇
  2019年   272篇
  2018年   352篇
  2017年   333篇
  2016年   364篇
  2015年   234篇
  2014年   352篇
  2013年   1721篇
  2012年   559篇
  2011年   601篇
  2010年   372篇
  2009年   397篇
  2008年   562篇
  2007年   572篇
  2006年   520篇
  2005年   460篇
  2004年   457篇
  2003年   425篇
  2002年   413篇
  2001年   489篇
  2000年   554篇
  1999年   386篇
  1998年   263篇
  1997年   195篇
  1996年   209篇
  1995年   204篇
  1992年   325篇
  1991年   305篇
  1990年   332篇
  1989年   314篇
  1988年   305篇
  1987年   266篇
  1986年   289篇
  1985年   294篇
  1984年   241篇
  1983年   242篇
  1980年   203篇
  1979年   286篇
  1978年   262篇
  1977年   201篇
  1976年   195篇
  1975年   271篇
  1974年   289篇
  1973年   322篇
  1972年   261篇
  1971年   242篇
  1970年   199篇
  1969年   221篇
  1968年   287篇
  1967年   262篇
  1966年   228篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
131.
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   
132.
Two different processes may be operative in human Pavlovian conditioning: signal learning and evaluative learning. Whereas most studies on evaluative conditioning focused on a mere demonstration of the phenomenon or on a theoretical analysis of the underlying processes, some basic parameters of evaluative learning are still unexplored. Hence, using the standard neutral picture--(dis)liked picture pairing paradigm (Baeyens, Eelen & Van den Bergh, 1990), in this study the effect of two parameters of evaluative conditioning was assessed on a between-subjects base, namely the Number of Acquisition Trials (2/5/10/20) and the Presentation Schedule of the stimulus pairs (blockwise or random). Additionally, the study included an exploratory analysis of the potential effects of the Evaluative Style of subjects (Feelers vs Thinkers, operationalized in terms of speed of emitting evaluations). Finally, the relationship between contingency awareness and evaluative learning was reassessed. Neutral-liked conditioning was found to be quadratically related to the number of acquisition trials (increase in effect up to 10 trials, decrease from 10 to 20 trials), whereas neutral-disliked conditioning linearly increased with increasing numbers of trials. Randomized vs blockwise presentation schedules of the stimulus pairs did differentially affect the overall pattern of conditioning, but in a way which was both unexpected and difficult to account for theoretically. Both the Evaluative Style of subjects and contingency awareness were demonstrated to be generally orthogonal to conditioned shifts in CS valence. Based on these findings, some practical suggestions are provided for the application of evaluating conditioning based therapeutical interventions to affective-behavioral disorders which are centred around inappropriate (dis)likes.  相似文献   
133.
Clinical material is presented leading to a discussion of beating fantasies which varies from Freud's model. Analysis shows that the fantasied role girls assign to mother as the punisher in the oedipal drama is equivalent to the fantasied role boys ascribe to father as castrator. For both sexes, castration anxiety spurs the internalization of parental prohibitions, the repression of oedipal wishes, and the subsequent structuralization of the superego. Mother establishes the "oedipal law" for the girl analogously to father's doing the same for the boy. The role that such fantasies play in the formation of the female superego is examined.  相似文献   
134.
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   
135.
Two studies compared the effectiveness of different strategies for promoting generalization of staff skills in teaching self-care routines to clients with developmental disabilities. In Study 1, 9 direct-care staff members of group homes were trained sequentially through four conditions: (a) the provision of written instructions, (b) performance-based training using a single client program exemplar and simulated clients (single case training), (c) performance-based training using actual developmentally delayed clients as trainees (common stimuli training), and (d) performance-based training using multiple client program exemplars with simulated clients (general case training). The results indicated that staff members did not reach all generalization criteria until general case training was provided. Because staff members had been trained sequentially through several conditions in Study 1, a second study controlled for potential sequence effects. In Study 2, 7 staff members were trained using only the general case strategy after baseline. All staff members reached generalization criteria with only general case training, replicating the findings of Study 1. Together, the two studies demonstrated that the general case training strategy was more effective at promoting generalized training effects across clients, settings, and client programs than other commonly used staff training approaches.  相似文献   
136.
The Colorado Occupant Protection Project (COPP) intervention provided police with brief instruction concerning the importance of citations for drivers' failure to use child safety seats and special coupons to accompany citations. Coupons were exchangeable by drivers for a safety seat and brief training in its use, plus a waiver of the $50 citation fine. Over 4.5 years of archival records were employed, using an ABA design and a comparison community to evaluate the program. Few tickets were issued for nonuse of safety seats during the 3-year baseline in either community. Citations for nonuse of safety seats increased to over 50 per month during the intervention period at the test site, whereas rates remained essentially zero at the comparison site. After the COPP intervention was removed at the intervention site, citation rates for nonuse of safety seats decreased to about 15 per month. Differences between intervention conditions and settings were statistically significant. During the intervention, officers were 44 times more likely to write citations than were controls. Results suggested that a behavioral program can increase police citation writing for child protection purposes.  相似文献   
137.
We assessed whether written task analyses would serve as textual prompts for performing functional tasks by persons with mild disabilities. Several variables that could influence the effectiveness of textual prompts to promote stimulus control were examined across four groups. A consistent finding was that written specific task analyses combined with end-of-trial performance feedback were effective for promoting the acquisition and generalization of several tasks. Performance transferred immediately to natural discriminative stimuli when the written task analyses and feedback were withdrawn for most tasks and participants. For 2 participants, transfer of stimulus control was accomplished by prompt fading, using individualized written task analyses either with or without performance feedback (Group 1). When feedback was not provided, the effectiveness of written specific task analyses was inconsistent across groups. In contrast to the controlling effects of written specific task analyses, written generic task analyses, which specified only major task outcomes, when combined with performance feedback (Group 1) did not control responding. Overall, this research demonstrated the effectiveness of written specific task analyses and performance feedback to promote stimulus control for persons with mild disabilities.  相似文献   
138.
The detectability of surface curvatures defined by optical motion was evaluated in three experiments. Observers accurately detected very small amounts of curvature in a direction perpendicular to the direction of rotation, but they were less sensitive to curvatures along the direction of rotation. Variations in either the number of points (between 91 and 9) or the number of views (from 15 to 2) had little or no effect on discrimination accuracy. The results of this study demonstrate impressive visual sensitivity to surface curvature. Several characteristics of this sensitivity to curvature are inconsistent with many computational models for deriving three-dimensional structure from motion.  相似文献   
139.
In its early stages, Parkinson's disease (P.D.) may be difficult to distinguish from major depression (M.D.) leading to inappropriate management. Both illnesses are characterized by psychomotor retardation. The neurovegetative symptoms used to diagnose M.D. are not specific and in P.D. may be due to the physical illness itself. Currently, differentiation of the two disorders relies on subjective clinical observation. Improved diagnostic accuracy based on more objective data is needed. To this end, this study used computerized acoustic analysis to contrast speech patterns in P.D. and M.D. The sample consisted of 30 P.D. patients without depression or dementia, 30 patients with uncomplicated M.D., and 31 normal controls, each 60 years of age or over. Of the acoustic variables studied, M.D. patients had significantly reduced rates of speech compared with P.D. patients. The data suggest that this temporal measure of speech may be useful in the differentiation of P.D. and M.D.  相似文献   
140.
Recently, several outstanding discussions of the structure of non-consequentialism have appeared. Two of these are Shelly Kagan's The Limits of Morality and a pair of articles by Warren Quinn, "Actions, Intentions, and Consequences: the Doctrine of Doing and Allowing" and "Actions, Intentions, and Consequences: the Doctrine of Double Effect." I would like to examine several related issues discussed by these authors. Another outstanding work to which I will refer in this article, but not discuss at great length, is Judith Jarvis Thomson's The Realm of Rights. The general topic with which I shall be concerned is the structure of a non-consequentialist moral theory. Non-consequentialism has two important features. In a non-consequentialist moral theory, (1) there is a permission not to maximize overall best consequences (this is sometimes referred to as an option), and (2) there are constraints on promoting overall best consequences (for example, we must not kill one innocent, non-threatening person for his organs to save five others). I shall use the works by Kagan, Quinn, and Thomson to help characterize further the elements of the non-consequentialist structure and to justify them.  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