全文获取类型
收费全文 | 165810篇 |
免费 | 7590篇 |
国内免费 | 155篇 |
出版年
2021年 | 1481篇 |
2020年 | 2761篇 |
2019年 | 3420篇 |
2018年 | 3423篇 |
2017年 | 3837篇 |
2016年 | 4547篇 |
2015年 | 3902篇 |
2014年 | 4779篇 |
2013年 | 23359篇 |
2012年 | 4308篇 |
2011年 | 3333篇 |
2010年 | 3780篇 |
2009年 | 4689篇 |
2008年 | 3586篇 |
2007年 | 3146篇 |
2006年 | 3821篇 |
2005年 | 3793篇 |
2004年 | 3328篇 |
2003年 | 2955篇 |
2002年 | 2739篇 |
2001年 | 2959篇 |
2000年 | 2868篇 |
1999年 | 2932篇 |
1998年 | 2799篇 |
1997年 | 2623篇 |
1996年 | 2559篇 |
1995年 | 2391篇 |
1994年 | 2362篇 |
1993年 | 2306篇 |
1992年 | 2394篇 |
1991年 | 2290篇 |
1990年 | 2115篇 |
1989年 | 2060篇 |
1988年 | 2033篇 |
1987年 | 2044篇 |
1986年 | 2023篇 |
1985年 | 2241篇 |
1984年 | 2390篇 |
1983年 | 2213篇 |
1982年 | 2332篇 |
1981年 | 2305篇 |
1980年 | 2152篇 |
1979年 | 2060篇 |
1978年 | 2112篇 |
1977年 | 2085篇 |
1976年 | 1872篇 |
1975年 | 1892篇 |
1974年 | 1935篇 |
1973年 | 1806篇 |
1972年 | 1413篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
851.
The purposes of this study were to assess the career development needs of entering medical students as measured by the Medical Career Development Inventory and to examine gender differences in responses to the inventory. A total of 115 entering medical students (representing two entering classes) took the inventory two months prior to matriculation. Analysis suggested that this sample of entering students had formed a vocational identity and that they had evaluated the suitability and viability of a commitment to a physician's career. However, the participants had not formed a clear picture of their specialty interest and goals. No significant gender differences were indicated. A recommended career assistance workshop is presented as appropriate for these students' needs. 相似文献
852.
853.
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
854.
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
855.
R F Lax 《Journal of the American Psychoanalytic Association》1992,40(2):455-473
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
856.
N E Adler H P David B N Major S H Roth N F Russo G E Wyatt 《The American psychologist》1992,47(10):1194-1204
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
857.
858.
Marylene Cloitre Richard G. Heimberg Craig S. Holt Michael R. Liebowitz 《Behaviour research and therapy》1992,30(6):609-617
Two studies assessed response time among clinically anxious subjects and normal controls when presented with threat, positive and neutral stimuli under perceptual (lexical decision) and semantic (category decision) task conditions. In Study 1, panic disorder subjects' (n = 14) performance was compared to that of matched normal controls (n = 14) while in Study 2 social phobic subjects (n = 24) were compared to matched normal controls (n = 24). Relative to matched normal controls, panic disorder subjects but not social phobics tended to show greater slowing in performance on the more cognitively complex (category) task. A second finding, consistent across both studies was that, compared to the normal control groups, both panic and social phobic groups showed significantly slowed responses to threat words in both the perceptual and semantic tasks. Such findings are directly counter to the predictions of a mood congruence hypothesis. This apparent contradiction is resolved by a review of the literature which indicates that mood-related facilitation effects are obtained only in tasks which tap awareness of threat information rather than speed of response. It is suggested that while anxiety may produce enhanced awareness of threat, it may inhibit responsiveness to it. The results of these studies are seen as consistent with ethological theories of inhibited motoric responses under certain threat conditions. Furthermore, the findings suggest that caution is indicated in interpreting slowed reaction time to threat stimuli in tasks such as the Stroop color naming task as purely the result of attentional processes. 相似文献
859.
860.