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   6332篇
  免费   1552篇
  国内免费   2篇
  2023年   39篇
  2022年   32篇
  2021年   113篇
  2020年   165篇
  2019年   476篇
  2018年   377篇
  2017年   508篇
  2016年   514篇
  2015年   429篇
  2014年   418篇
  2013年   850篇
  2012年   437篇
  2011年   375篇
  2010年   345篇
  2009年   315篇
  2008年   311篇
  2007年   235篇
  2006年   203篇
  2005年   226篇
  2004年   168篇
  2003年   179篇
  2002年   169篇
  2001年   119篇
  2000年   104篇
  1999年   70篇
  1998年   24篇
  1997年   31篇
  1996年   23篇
  1995年   29篇
  1994年   24篇
  1993年   26篇
  1992年   23篇
  1991年   20篇
  1990年   21篇
  1989年   19篇
  1988年   26篇
  1987年   22篇
  1986年   19篇
  1985年   29篇
  1984年   28篇
  1983年   21篇
  1979年   26篇
  1978年   17篇
  1977年   21篇
  1976年   23篇
  1975年   20篇
  1974年   23篇
  1973年   18篇
  1970年   17篇
  1967年   21篇
排序方式: 共有7886条查询结果,搜索用时 15 毫秒
181.
This study evaluated 2 methods of disseminating an empirically validated smokeless tobacco intervention delivered during routine dental care. Twenty cities within 12 states were stratified and then randomized to 1 of 3 groups: personalized instruction (PI), self-study (SS), or delayed training (DT) control. Dental hygienists in the SS condition were sent a manual and video. Those in the PI condition were recruited to attend a workshop. Thirty-seven percent of eligible hygienists agreed to participate. At 12 months postenrollment, hygienists in the SS and PI conditions significantly increased their "Assist" behaviors (discuss cessation techniques, help patient set a quit date, and provide cessation materials) and reported fewer perceived barriers to delivering the intervention as compared with hygienists in DT. An economic analysis suggests that SS is more cost-effective than PI.  相似文献   
182.
Studies of appetite in mammals emphasize that meal size is learned, but lactation and parental care constrain testing of naive individuals. Neonatal reptiles, in contrast, are self-sufficient foragers. The authors examined the effect of prey size on meal size in primivorous (at first feeding) northern watersnakes (Nerodia sipedon). When offered an excess of small prey (2%-20% of snake mass), neonates ate significantly smaller meals (M = 23.5% of snake mass) than when offered a single huge item (range = 32%-55%). The authors conclude that (a) the taking of smaller meals is not a learned effect, (b) there may be a satiety threshold for meal size rather than a target, (c) oropharyngeal stimuli may provide satiety cues, and (d) huge meals may have fitness costs.  相似文献   
183.
Approximately 800 youths from the Children in the Community Study (Cohen & Cohen, 1996) have been assessed prospectively for over 20 years to study personality disorders (PDs) in adolescents and young adults. In this article we evaluate the Children in the Community Self-Report (CIC-SR) Scales, which were designed to assess DSM-IV PDs using self-reported prospective data from this longitudinal sample. To evaluate convergent validity, we assessed concordance between the CIC-SR Scales and the Structured Clinical Interview for DSM-IV Personality Disorders (SCID-II; First, Gibbon, Spitzer, Williams, & Benjamin, 1995) in 644 participants at mean age 33. To assess predictive validity, we used CIC-SR Scales at mean age 22 to predict subsequent CIC-SR and SCID-II Personality Questionnaire scores at mean age 33. In these analyses the CIC-SR Scales matched or exceeded benchmarks established in previous comparisons between self-report instruments and structured clinical interviews. Unlike other self-report scales, the CIC-SR did not appear to overestimate diagnoses when compared with SCID-II clinical diagnoses.  相似文献   
184.
After a person has become stuck on a problem, they sometimes achieve a clear and sudden solution through insight--the so-called Aha! experience. Because of its distinctive experience, the origins and characteristics of insight have received considerable attention historically in psychological research. However, despite considerable progress in characterizing insight, the underlying mechanisms remain mysterious. We argue that research on insight could be greatly advanced by supplementing traditional insight research, which depends on a few complex problems, with paradigms common in other domains of cognitive science. We describe a large set of mini-insight problems to which multiple methods can be applied, together with subjective reports to identify insight problem-solving. Behavioral priming and neuroimaging methods are providing evidence about what, where, and how neural activity occurs during insight. Such evidence constrains theories of component processes, and will help to demystify insight.  相似文献   
185.
186.
187.
188.
Impulsivity and hostility are often thought to be interrelated among depressed patients with suicidal behavior, but few studies have examined this relationship empirically. In this study, we assessed trait impulsivity and hostility among 52 DSM-IV bipolar subjects with and without histories of suicide attempts. Impulsivity and hostility were correlated among attempters (r = .41, p = .03) but not non-attempters (r = .22, p = .28). As compared to non-attempters, attempters had significantly higher levels of overall hostility, more extensive subcomponents of hostility, and a trend toward higher overall impulsivity. Associations between lifetime suicide attempts and overall hostility were significant while controlling for current depression severity and lifetime illness duration. Aggression and impulsivity appear linked among bipolar patients with lifetime suicide attempts but may be independent constructs among non-attempters. The presence of both factors may elevate risk for suicidal behavior.  相似文献   
189.
Witt JK  Proffitt DR  Epstein W 《Perception》2004,33(5):577-590
Perceiving egocentric distance is not only a function of the optical variables to which it relates, but also a function of people's current physiological potential to perform intended actions. In a set of experiments, we showed that, as the effort associated with walking increases, perceived distance increases if the perceiver intends to walk the extent, but not if the perceiver intends to throw. Conversely, as the effort associated with throwing increases, perceived distance increases if people intend to throw to the target, but not if they intend to walk. Perceiving distance combines the geometry of the world with our behavior goals and the potential of our body to achieve these goals.  相似文献   
190.
Children who experienced a highly stressful natural disaster, Hurricane Andrew, were interviewed within a few months of the event, when they were 3-4 years old, and again 6 years later, when they were 9-10 years old. Children were grouped into low, moderate, or high stress groups depending on the severity of the experienced storm. All children were able to recall this event in vivid detail 6 years later. In fact, children reported over twice as many propositions at the second interview as at the first. At the initial interview, children in the high stress group reported less information than children in the moderate stress group, but 6 years later, children in all three stress groups reported similar amounts of information. However children in the high stress group needed more questions and prompts than children in the other stress groups. Yet children in the high stress group also reported more consistent information between the two interviews, especially about the storm, than children in the other stress groups. Implications for children's developing memory of stressful events are discussed.  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