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   32158篇
  免费   613篇
  国内免费   3篇
  2021年   119篇
  2020年   172篇
  2019年   189篇
  2018年   3745篇
  2017年   3049篇
  2016年   2515篇
  2015年   402篇
  2014年   323篇
  2013年   995篇
  2012年   954篇
  2011年   2819篇
  2010年   2767篇
  2009年   1705篇
  2008年   2056篇
  2007年   2495篇
  2006年   321篇
  2005年   466篇
  2004年   401篇
  2003年   318篇
  2002年   277篇
  2001年   453篇
  2000年   443篇
  1999年   292篇
  1998年   128篇
  1997年   98篇
  1996年   107篇
  1995年   97篇
  1992年   209篇
  1991年   216篇
  1990年   210篇
  1989年   201篇
  1988年   207篇
  1987年   184篇
  1986年   172篇
  1985年   173篇
  1984年   158篇
  1983年   114篇
  1982年   114篇
  1979年   149篇
  1977年   95篇
  1975年   138篇
  1974年   157篇
  1973年   182篇
  1972年   155篇
  1971年   141篇
  1970年   124篇
  1969年   133篇
  1968年   175篇
  1967年   131篇
  1966年   141篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
One major purpose of this study was to identify environmental factors related to suicide in long-term care facilities. Questionnaires were mailed to a random sample of administrators at 1,080 facilities. Information was collected on facility characteristics, overt suicide, and intentional life-threatening behavior. Chi-square analyses revealed 4 environmental characteristics related to suicidal behavior and deaths from suicide: staff turnover, size, auspices, and per diem cost. More suicides occurred in larger facilities and facilities with higher staff turnover. Religious or "other" facilities experienced more suicidal deaths than public or private facilities; facilities charging less experienced more deaths.  相似文献   
102.
Elderly women in subjectively good health--free of acute illness and major sleep pathologies--who were self-identified as good (n = 22) and poor (n = 16) sleepers were compared on measures of physical health, psychological symptoms, psychosocial status, and life-style. Poor sleepers reported longer sleep latencies, less total sleep time, more nonrestorative sleep, and more daytime fatigue than did good sleepers. Sleep recordings confirmed subjective reports, with shorter total sleep times and trends for lower sleep efficiency, longer sleep latencies, and more wake-after-sleep onset among women with subjective poor sleep. Poor sleepers also were more frequent users of sedative-hypnotic medications in the past. Current medication use, alcohol and caffeine use, daytime napping, and exercise were equivalent in both groups. Psychosocial status failed to discriminate groups. Poor sleepers reported significantly more psychological symptoms than did good sleepers. The levels of both psychological symptoms and sleep disturbance were mild.  相似文献   
103.
104.
105.
This brief report proposes an extension of the traditional Alternating Treatments Design that would be acceptable to use in hospital and residential settings where subjects are often not concurrently available. Concerns about the inability of traditional designs to work in these special situations and the emergence of a “scientist–practitioner split” are discussed. An example of how the Extended Alternating Treatments Design might be used is provided.  相似文献   
106.
Among adult rats, gustatory stimuli are easily associated with illness, but not with external unconditioned stimuli such as footshock. Recent evidence indicates, however, that this cue-to-consequence specificity may vary ontongenetically. The present studies examined the acquisition of an aversion to a taste paired with footshock in 5- and 15-day-old rats. Consistent with previous reports, 5-day-old rats avoided the taste that preceded footshock, while 15-day-old subjects did not express an aversion to the taste paired with footshock. Exposure to the training context for either 1 or 5 h prior to conditioning disrupted taste-footshock conditioning in the 5-day-old subjects. For the 15-day-old subjects, 1 h of pre-conditioning exposure to the training context had no effect on conditioning, whereas a longer duration of preexposure promoted conditioning to the taste cue. The results suggest ontogenetic differences in stimulus selection.  相似文献   
107.
The naturalistic fallacy occurs when a person reads a report of scientific research and concludes that the moral implication of the research was included in the article when, in fact, it was not. For example, the fallacy is committed when a study contains the conclusion that TV advertising increases preference for sugar-based foods, but the reader later believes that the study concluded that TV advertising should be controlled. Previous research indicates that the commission of the fallacy was strong when memory for social research was tested. The present study showed that the commission of the fallacy was stronger when the research which was read involved children as subjects compared to adult subjects. Increased empathy for the subjects of a research article strengthens commission of the fallacy.  相似文献   
108.
Effects of personal experience on self-protective behavior   总被引:11,自引:0,他引:11  
This article seeks to further our understanding of self-protective behavior by examining the effects of a particularly powerful stimulus to action: personal experience. It reviews the effects of automobile accidents on seat belt use, criminal victimization other than rape on individual crime prevention efforts, natural hazards experience on both natural hazards preparedness and compliance with evacuation warnings, and myocardial infarction on smoking. Theories suggesting mechanisms that could link personal experience to behavior are described, and data concerning the effects of experience on some key variables in these theories are discussed. Tentative propositions are offered to resolve the many apparent discrepancies in this literature. These propositions concern the effects of experience on risk perceptions, the influence of experience on risk salience, the specificity of responses to victimization, and the duration of experience effects.  相似文献   
109.
Clinical judgment, clinical training, and professional experience   总被引:1,自引:0,他引:1  
Reviews studies on training, experience, and clinical judgment. The results on the validity of judgments generally fail to support the value of on-the-job experience in mental health fields. The validity results do provide limited support for the value of training. Other results suggest that experienced clinicians are better than less experienced judges at knowing which of their judgments are likely to be correct and which are likely to be wrong. Reasons why clinicians have trouble learning from experience are given. Recommendations are made for improving training and clinical practice.  相似文献   
110.
Despite importance for theories of perception, controversy exists as to whether information is available to the perceptual system about involuntary as well as voluntary eye movements. We measured the perceived direction of targets flashed briefly in an otherwise dark field during the primary phase of optokinetic afternystagmus (OKAN), an involuntary eye movement that persists in darkness following optokinetic stimulation. Perceived direction was measured by unseen pointing in one experiment and by pointing made under visual control in a second experiment. Pointing was essentially veridical in both experiments, indicating that accurate extra-retinal information about eye position (presumably, as efference copy) exists for OKAN. Illusory motion of visual targets, which can occur during involuntary oculomotor responses, therefore cannot be attributed to a lack of efference-copy signals for such eye movements.  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