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   22194篇
  免费   116篇
  2023年   11篇
  2022年   11篇
  2021年   20篇
  2020年   44篇
  2019年   44篇
  2018年   3518篇
  2017年   2856篇
  2016年   2287篇
  2015年   232篇
  2014年   132篇
  2013年   270篇
  2012年   647篇
  2011年   2492篇
  2010年   2580篇
  2009年   1541篇
  2008年   1794篇
  2007年   2262篇
  2006年   93篇
  2005年   288篇
  2004年   240篇
  2003年   178篇
  2002年   126篇
  2001年   64篇
  2000年   70篇
  1999年   46篇
  1998年   56篇
  1997年   44篇
  1996年   39篇
  1995年   25篇
  1994年   25篇
  1993年   33篇
  1992年   24篇
  1991年   22篇
  1990年   15篇
  1989年   14篇
  1988年   10篇
  1987年   17篇
  1986年   9篇
  1985年   13篇
  1984年   10篇
  1983年   7篇
  1982年   16篇
  1981年   10篇
  1980年   11篇
  1979年   10篇
  1978年   7篇
  1977年   10篇
  1975年   7篇
  1974年   6篇
  1973年   6篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
151.
In a sample of 351 young adults, the authors assessed whether borderline personality disorder (BPD) features prospectively predicted negative outcomes (poorer academic achievement and social maladjustment) over the subsequent 2 years, over and above gender and both Axis I and Axis II psychopathology. Borderline traits were significantly related to these outcomes, with impulsivity and affective instability the most highly associated. The present findings suggest that the impulsivity and affective instability associated with BPD leads to impairment in relating well with others, in meeting social role obligations, and in academic or occupational achievement. Therefore, these may be especially important features to target in interventions for BPD.  相似文献   
152.
The authors describe the effects of practice conditions in motor learning (e.g., contextual interference, knowledge of results) within the constraints of 2 experimental variables: skill level and task difficulty. They use a research framework to conceptualize the interaction of those variables on the basis of concepts from information theory and information processing. The fundamental idea is that motor tasks represent different challenges for performers of different abilities. The authors propose that learning is related to the information arising from performance, which should be optimized along functions relating the difficulty of the task to the skill level of the performer. Specific testable hypotheses arising from the framework are also described.  相似文献   
153.
A startle stimulus has been shown to elicit a ballistic response in a reaction time (RT) task at very short latencies without involvement of the cerebral cortex (J. Valls-Sole, J. C. Rothwell, F. Gooulard, G. Cossu, & E. Munoz, 1999). The present authors examined the nature of the startle response. A simple RT task was used in which 8 participants performed arm extension movements to 3 target distances (20 degrees, 40 degrees, and 60 degrees ) in a blocked design. An unpredictable startling acoustic stimulus (124 dB) replaced the imperative stimulus in certain trials. The authors verified the presence of a startle response independent from the prepared response by observing electromyographic (EMG) activity in sternocleidomastoid and orbicularis oculi muscles. Findings indicated that when the participant was startled, the intended voluntary response was produced at significantly shorter response latencies. Furthermore, the kinematic variables of the observed response during startle trials for all 3 target distances were mostly unchanged. The EMG characteristics of the responses were not modified, indicating that the response produced was indeed the prepared and intended response.  相似文献   
154.
This article investigates the transition to memory-based performance that commonly occurs with practice on tasks that initially require use of a multistep algorithm. In an alphabet arithmetic task, item response times exhibited pronounced step-function decreases after moderate practice that were uniquely predicted by T. C. Rickard's (1997) component power laws model. The results challenge parallel strategy execution models as developed to date and they demonstrate that the shift to retrieval is an item-specific, as opposed to task-general, learning phenomenon. The results also call into question the entire class of smooth speed-up functions as global empirical learning laws. It is shown that overlaying of averaged item fits on averaged data can provide a sensitive test for model sufficiency. Strategy probes agreed with strategy inferences that were based on step-function speed-up patterns, supporting the validity of the probing technique.  相似文献   
155.
156.
Modern experiments in the behavioral sciences frequently employ several items of electronic equipment such as computers, monitoring devices, stimulus presentation equipment, and response collection systems. In many cases it would be advantageous for these items to communicate directly with each other. Such communication may facilitate greater automation of experiments (i.e., reduced experimenter influences during the experiment), more precise experiment control (i.e., superior timing and synchronization capabilities of electronic devices), and greater accuracy of data collection (i.e., reduced ambiguity of participant responses). Many electronic experiment devices already provide external interfacesthrough which communication with other devices can be implemented. The most common is based on the RS-232 protocol, which is also found in all standard PCs. Therefore, Microsoft Windows based computers can be programmed to control experiments by communicating directly with electronic experiment devices. We show how to implement this RS-232 interconnection between devices and a Windows PC using currently available software tools.  相似文献   
157.
Faculty members at Canadian business schools were surveyed regarding their ethical perceptions of behaviours related to undergraduate instruction. Fifty-five behavioural statements were listed and respondents were asked to rate the extent to which they felt each behaviour was ethical or unethical. The only item that respondents endorsed as unequivocally unethical (90% indicated it was definitely unethical) was Becoming sexually involved with an undergraduate in one of your classes. We also compared the results of our sample to those of an American sample. Overall, an interesting pattern of differences emerged between the responses obtained in Canada and the U.S. In general, the direction of the significant differences was such that Canadian professors viewed the behaviours in question as less ethical than did their American counterparts.  相似文献   
158.
The latent structure of the Penn State Worry Questionnaire (PSWQ) was evaluated with confirmatory factor analyses (CFAs) in 1200 outpatients with DSM-IV anxiety and mood disorders. Of particular interest was the comparative fit and interpretability of a two-factor solution (cf. Behaviour Research and Therapy 40 (2002) 313) vs. a one-factor model that specified method effects arising from five reverse-worded items. Consistent with prediction, the superiority of the one-factor model was demonstrated in split-sample CFA replications (ns=600). Multiple-group CFAs indicated that the measurement properties of the PSWQ were invariant in male and female patients. In addition to their direct relevance to the psychometrics of the PSWQ, the results are discussed in regard to methodological considerations for using factor analytic methods in the evaluation of psychological tests.  相似文献   
159.
The aims of this study were to investigate exposure-based treatments for cynophobia (dog phobia) and to test a newly developed hybrid imaginal exposure treatment that we have named active imaginal exposure. The treatment introduces an in vivo coping component to imaginal exposure whereby the patient physically performs coping responses to an imagined feared stimulus. Eighty-two participants meeting DSM-IV criteria for specific phobia (animal subtype) were randomly assigned to one of three 30-min. treatments: (a) active-imaginal exposure (AI), (b) imaginal exposure alone (IE), or (c) graduated in vivo exposure (IV). Participants completed a behavioral approach test at pre, post, and four-week follow-up. Significant pre- to posttreatment improvement was observed in all three treatment conditions. Response rates at posttreatment were 51.9, 62.1, and 73.1% for the IE, AI, and IV groups respectively. Likewise, effect sizes at posttreatment were 0.76, 1.41, and 1.55 for the IE, AI, and IV groups respectively. Although in the predicted direction, the between group differences were not significant. A similar pattern of results was observed at follow-up. Further, safety behavior utilization during treatment was associated with less improvement--particularly in the two imaginal treatment conditions. Exposure treatments of dog phobia appear feasible and effective in reducing phobic fear and avoidance associated with dog phobia. Furthermore, preliminary evidence suggests that our active-imaginal exposure treatment may be a viable alternative to in vivo exposure.  相似文献   
160.
In this article, the authors assessed whether continuously scaled symptom parameters derived from growth models (T. M. Piasecki et al., 2003) are linked to smoking at long-term follow-up by using data from a large-scale clinical trial (N = 893). Results revealed that higher withdrawal intercepts, positive linear slopes, and greater volatility were all positively associated with relapse, and cigarette coefficients (indicating smoking-induced withdrawal reduction) were negatively related to relapse. In models keyed around the first lapse to smoking, those destined to lapse reported more severe withdrawal during abstinence, and withdrawal patterns discriminated groups defined according to lapse duration. The findings complement earlier heterogeneity studies in implicating the pattern of changing withdrawal symptoms over time as a factor strongly associated with smoking relapse.  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