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   5516篇
  免费   241篇
  国内免费   1篇
  2023年   37篇
  2022年   30篇
  2021年   50篇
  2020年   83篇
  2019年   90篇
  2018年   150篇
  2017年   149篇
  2016年   163篇
  2015年   136篇
  2014年   146篇
  2013年   710篇
  2012年   287篇
  2011年   259篇
  2010年   188篇
  2009年   163篇
  2008年   263篇
  2007年   296篇
  2006年   220篇
  2005年   172篇
  2004年   149篇
  2003年   187篇
  2002年   184篇
  2001年   94篇
  2000年   96篇
  1999年   96篇
  1998年   81篇
  1997年   68篇
  1996年   78篇
  1995年   53篇
  1994年   61篇
  1993年   52篇
  1992年   63篇
  1991年   60篇
  1990年   63篇
  1989年   44篇
  1988年   45篇
  1987年   43篇
  1986年   45篇
  1985年   45篇
  1984年   62篇
  1983年   42篇
  1982年   53篇
  1981年   44篇
  1980年   37篇
  1979年   48篇
  1978年   28篇
  1977年   34篇
  1976年   33篇
  1974年   32篇
  1973年   30篇
排序方式: 共有5758条查询结果,搜索用时 46 毫秒
81.
The present study evaluated the efficacy of a new intervention, Guided Imaginal Coping (GIC), compared to imaginal exposure (IEX), and a waiting-list control (WLC) condition among 24 clinic outpatients meeting DSM-III-R criteria for panic disorder (PD) or PD with agoraphobia. GIC was the more consistently effective intervention, with individuals demonstrating significant improvement in frequency and severity of panic attacks (Pas) as well as significant reductions in physiological and subjective arousal to provocative imagery. Individuals in the IEX intervention demonstrated less consistent improvement on the dependent measures, while individuals in the WLC condition essentially remained unchanged. Both GIC and IEX were effective according to a composite measure of clinically significant improvement. However, only GIC was superior to the WLC condition when clinical improvement was defined as zero PAs at follow-up. These findings, while preliminary, suggest that GIC can be added to the armamentarium of effective approaches to treating PD.  相似文献   
82.
This study emanated from the long-standing question of whether a maternal bonding process similar to other mammalian species occurs in humans. The perceptions of adult adoptees and a matched sample of non-adoptees about their parents' behaviours towards them were compared on an original Parental Solicitude Scale. As hypothesized, birth children perceived their mothers as the more solicitous parent, but ratings of adoptive mothers showed a unilateral decline. Further, the differential ratings for birth and adoptive mothers occurred mostly for the factors labelled benignity vs abuse and tolerance vs control, rather than caretaking vs neglect, which was congruent to reported effects in prior studies of lack of mother-infant contact during the sensitive period for bonding. An alternative explanation of the data was also tested but not substantiated.  相似文献   
83.
Freedman (1990) introduced a computer analog of the shuttlebox paradigm and presented results to show that this analog could be used for studying human avoidance conditioning. In the present study, a first experimental phase was conducted to test how the fact that the tone was considered aversive in the instructions and the intensity of this tone affect avoidance behavior. In a transfer-of-control test phase, it was tested as to whether the warning stimulus presented as a cue to the aversive stimulus had acquired either aversive or informative quality. An effect of instructions was observed for both levels of the auditive stimulus, and a stimulus effect was found for those groups that were given the instructions that described the tone as aversive. In the case of subjects who in the first phase achieved a certain learning criterion, it was recorded how often they in the second phase selected a condition in which the warning signal of the first phase was not presented. No transfer of control was observed. Thus, no positive evidence was found indicating that Freedman’s computer analog could be used for studying human avoidance conditioning.  相似文献   
84.
Two visual half-field experiments tested Moscovitch’s (1979) proposition that cerebral asymmetry does not concern the earliest perceptual stages but only later processing. Subjects were briefly shown displays that included one (Experiment 1) or two (Experiment 2) types of forms differing in size and which, according to previous evidence, might lead to opposite laterality effects. Laterality effects were assessed for correct detections and for illusory conjunctions, both in terms of raw detection scores and in terms of perceptual discriminability (dr scores). In Experiment 1, displays included either rectangles or triangles. In the first case, the target was a cross; in the second case, it was a Star of David. A hemifield x size interaction was observed both on correct detections and on associated discriminability. Yet, no such interaction was obtained for illusory conjunctions or for associated d’ scores. In Experiment 2, the two types of forms were presented simultaneously, with the small ones either inside or outside the large ones. No laterality effects were observed. Some implications of these data for both hemispheric asymmetry and feature integration issues are discussed. The results suggest that early preattentive processes of feature extraction are not lateralized, whereas some integrative mechanisms, such as Treisman’s (1988) focal attention, may operate differently in the two hemispheres.  相似文献   
85.
The LogicR4 is obtained by adding the axiom (A vB(AvB) to the modal relevant logicNR. We produce a model theory for this logic and show completeness. We also show that there is a natural embedding of a Kripke model forS4 in eachR4 model structure.We are indebted to several people for discussions relating to the topic of this paper, in particular, Kit Fine, John Slaney, J. M. Dunn, Jacques Riche, M. A. McRobbie, and Jill LeBlanc. We would also like to thank the Automated Reasoning Project for material assistance. Mares would like to thank The Social Sciences and Humanities Research Council of Canada for fellowships 456-89-0128 and 457-90-0081, which supported him while writing this paper.  相似文献   
86.
Lever pressing in rats was maintained by continuous and intermittent schedules of food while defecation was monitored. In Experiment 1, reinforcement densities were matched across variable-ratio and variable-interval schedules for three pairs of rats. Defecation occurred in all 3 rats on the variable-ratio schedule and in all 3 rats on the yoked variable-interval schedule. In Experiment 2, fixed-ratio and fixed-interval schedules with similar reinforcement densities maintained lever pressing. Defecation occurred in 3 of 4 rats on the fixed-ratio schedule and in 4 of 4 rats on the fixed-interval schedule. Almost no defecation occurred during continuous reinforcement in either experiment. These results demonstrate that defecation may occur during both ratio and interval schedules and that the inter-reinforcement interval is more important than the behavioral requirements of the schedule in generating schedule-induced defecation.  相似文献   
87.
Three groups of subjects were tested to investigate the effect of language on the relationship between recall span and articulation rate. Native English-speaking monolinguals and native Chinese-speaking monolinguals recalled only English or Chinese words, respectively. Chinese-English bilinguals recalled both English and Chinese words. Articulation rates for English and Chinese monolinguals and Chinese-English bilinguals in each language were also obtained. When recall span was regressed on articulation rate, the slopes for Chinese and English words were significantly different for the Chinese-English bilinguals. This difference was not due to language proficiency but to phonological differences between English and Chinese.  相似文献   
88.
In Experiment 1, haptically available object properties that would be diagnostic for constrained common object classification at the basic and subordinate levels were elicited in a questionnaire. The results are considered in terms of the nature of the haptically derived representations of common objects. Initial data are also presented regarding knowledge of the natural co-occurrence of properties in haptic object perception. In Experiment 2, the hand movements executed during haptic classification of manipulable common objects were examined. Manual exploration consisted of a two-stage sequence, an initial generalized "grasp-and -lift" routine, followed by a series of more specialized hand-movement patterns strongly driven by knowledge of the property diagnosticity for the specific object (obtained in Experiment 1). The current results may guide computational models of human haptic object classification and the development of perceptual systems for robots equipped with sensate dextrous hands, capable of intelligent exploration, recognition, and manipulation of concrete objects.  相似文献   
89.
90.
Medical expertise asa function of task difficulty   总被引:4,自引:0,他引:4  
This paper is concerned with factors that disrupt the pattern of forward reasoning characteristic of experts with accurate performance. Two experiments are described. In the first, the performances of cardiologists, psychiatrists, and surgeons in diagnostic explanation of a clinical problem in cardiology were examined. In the second, the performances of cardiologists and endocrinologists in diagnostic explanation of clinical problems within and outside their domains of expertise were examined. The performances of researchers and practicing physicians are also compared. The results of Experiment 1 replicated earlier results regarding the relationship between forward reasoning and accurate diagnosis. There were no differences in recall as a function of expertise. Experts did not show any bias toward using specific knowledge from their own areas of expertise. The results of Experiment 2 showed that the breakdown of forward reasoning was related to the structure of the task. In particular, nonsalient cues induced some backward reasoning even in subjects with accurate diagnoses. Some differences were also found between the types of explanation used by researchers and practitioners. The practitioners referred more to clinical components in their explanations, whereas the researchers focused more on the biomedical components.  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