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   82173篇
  免费   3253篇
  国内免费   46篇
  85472篇
  2020年   924篇
  2019年   1168篇
  2018年   1633篇
  2017年   1692篇
  2016年   1730篇
  2015年   1196篇
  2014年   1474篇
  2013年   6960篇
  2012年   2608篇
  2011年   2750篇
  2010年   1713篇
  2009年   1671篇
  2008年   2521篇
  2007年   2522篇
  2006年   2214篇
  2005年   2018篇
  2004年   1939篇
  2003年   1773篇
  2002年   1829篇
  2001年   2571篇
  2000年   2449篇
  1999年   1892篇
  1998年   960篇
  1997年   865篇
  1996年   796篇
  1995年   790篇
  1994年   778篇
  1993年   787篇
  1992年   1576篇
  1991年   1442篇
  1990年   1481篇
  1989年   1305篇
  1988年   1299篇
  1987年   1253篇
  1986年   1270篇
  1985年   1292篇
  1984年   1094篇
  1983年   975篇
  1982年   763篇
  1979年   1133篇
  1978年   835篇
  1975年   973篇
  1974年   1028篇
  1973年   1050篇
  1972年   878篇
  1971年   805篇
  1969年   785篇
  1968年   950篇
  1967年   907篇
  1966年   786篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
981.
982.
Factors affecting spontaneous alternation behavior (SAB) in animals, for example, age, gender and species studied; type of apparatus and cues employed; and neuro-anatomical, neuro-chemical and motivational status of the organism, were reviewed. Despite a myriad of experiments showing interesting main effects of such variables, little research has been performed assessing the interactive affects of these factors on alternation behavior. For example, psychologists test rats in central nervous system (CNS) lesion studies, whereas psychopharmacologists tend to assess SAB in mice. Most importantly, studies have not been reported investigating the possible interactions among species, brain lesions and drugs. This is an unfortunate omission since several important alternation models include propositions relating to cholinergic and/or serotonergic coding in the hippocampus. Examination of behavioral studies revealed the primary cue for alternation among invertebrates to be body turn, whereas vertebrates rely primarily on directional and odor cues. Reference to the seeking of stimulus change remains the most compelling motivational account of why animals manifest this ubiquitious and reliable behavior pattern. This review and the unpublished studies were supported by Research Grants MH16962, MH21288, and MH36491 from the National Institute of Mental Health and the Wake Forest University Research and Publication Fund.  相似文献   
983.
Computing stress     
This article is based on a review of recent literature on “computing stress”; that is, on the psychological stress effects of working with computer systems. Current research into the sources of computer-related stress has tended to concentrate on those employees who operate Visual Display Units (VDUs), either on a full-time professional basis as word-processor (WP) operators, data-entry clerks, secretaries, or those dealing with enquiries from the public; or employees who use the VDU irregularly as part of their other duties. A few studies have looked at specific occupation groups, such as printers (Kalimo & Lepp?nen, 1985), information technology professionals (programers and analysts), process workers, and college students (Sproull, Kiesler, & Zubrow, 1984). Generally, however, research has been carried out on office workers, more often women, carrying out administrative tasks. An attempt is made to identify those potential work-related stressors that have been isolated by these studies, and also included are criticisms of the general methodologies used in many of them. The terms “visual display unit,” “visual display terminal,” VDU, VDT, and “terminal” are used interchangeably.  相似文献   
984.
Neonatal ducklings and chickens were tested for responsiveness to a pulsing pure tone that was as similar as possible to the mallard maternal alarm call. It is known that ducklings momentarily cease vocalizing when they hear the alarm call and that chicks do the same when they hear pure tones. The duration of peep suppression can thus be used as a measure of whether subjects of either species heard the stimulus. Chicks might not be as sensitive as ducklings to a mallard alarm call because the signal is less significant to them. An adaptive or staircase procedure was used to estimate absolute thresholds, and group psychometric functions were reconstructed for each species from the trial-by-trial data. Ducklings had lower thresholds than chickens as well as steeper psychometric functions to this stimulus. The results suggest that more sensitive and consistent behavioral responses can be elicited by naturalistic sounds than by more arbitrary acoustic stimuli.  相似文献   
985.
Human relations training includes counselling as an important ingredient. This case-study reports the learning of one primary deputy headteacher during a six-day course, and her continuing efforts to use and extend that learning during the following year. She reported an improvement in classroom discipline, and less stressful and more effective relationships with colleagues and pupils, linking these gains with insights and skills developed on the course. The value to course designers of goal-setting structures is illustrated by the study. Such structures provide an opportunity to take part in, and study, counselling interventions which have real problems as their focus.  相似文献   
986.
The factors perceived as helpful by members of three different types of self-help groups are examined, using the 12 factors identified by Yalom as operative in group psychotherapy. Questionnaires were given to 45 members of self-help groups, asking for their views of the most and least helpful aspects of their experiences of their group, and for their judgement of its effectiveness. Results indicated that members of a group concerned with social and personal support in the face of a socially problematic situation (widowhood) found the experience of Universality to be the most helpful factor, while Self-Disclosure was least helpful. Members from a group for the physically sick (asthma sufferers) also reported the least helpful factor to be Self-Disclosure, but said that the most helpful factor was Guidance. By contrast, the group concerned with providing 'therapy' for depressives reported Cohesiveness to be most helpful, and Guidance to be least helpful. Comparison with other studies using similar methodologies with different group populations suggests that the factors likely to be effective in self-help groups for the socially unsupported and physically sick on the one hand, and for the psychologically disturbed on the other, may differ.  相似文献   
987.
Adaptation and reaction-time techniques were used to examine the role of different spatial-frequency channels in the perception of local and global structure. Subjects were shown figures consisting of a large C composed of smaller Cs and asked to identify the orientation of either the global C or its local elements. Prior to performing the task subjects were adapted to different spatial frequencies and the effect on subsequent performance was assessed. Two main results were found. First, the adapting frequency that most affected the global task was often lower than that most affecting the local task, suggesting that high and low frequencies independently code the structure of an image. Second, reaction time to global figures was often faster than to local figures at all levels of detectability, again suggesting a role of low-frequency channels in global processing.  相似文献   
988.
Static depiction of movement   总被引:1,自引:0,他引:1  
A number of pictorial devices were compared in order to assess their relative effectiveness in depicting events. Effectiveness, as measured by a rating task, did not seem to be a function of the classification of a device as natural or metaphorical. Rather, it depended on whether a given device highlighted a distinctive aspect of a particular event (running, jumping, or moving), or simply modified the event. This observation was buttressed by the existence in a forced-choice task of a category boundary for depictions of running (pictures with a certain device were seen as running, those without it were not) but not for moving or jumping. Even preschool children displayed some understanding of metaphorical devices. They chose figures with those devices as running faster than the experimental standard. Results are discussed in the context of Kennedy's characterization of pictorial metaphors and Gibson's framework for understanding the relationship between pictorial and environmental information.  相似文献   
989.
AN IDIOGRAPHIC APPROACH TO THE STUDY OF WOMEN'S ACHIEVEMENT STRIVING   总被引:1,自引:0,他引:1  
Biographical interviews with 80 women ranging in age from the late teens to the 80s (Mean Age = 46.8 years; SD = 7.8 years) elicited information concerning personality characteristics that predispose women toward achievement-striving behavior, taking into account the effects of family, friends, and role models. When asked if they had ever been in a situation where they were about to succeed and feared the success, the majority of women (91 %) replied "no". A large percentage of women (96%) did report that they wonder if their achievements are worth it and asked "success at what cost?" In addition, compared to older women, younger women were more concerned with interpersonal relationships and less concerned with competitive achievement. The reality status of the fear of success construct as well as methodological advances in its measurement are discussed.  相似文献   
990.
Newcombe, Bandura, and Taylor developed a questionnaire measuring participation in space-related activities. The activities were classified as masculine, feminine, or neutral in gender stereotyping. A short version of this questionnaire was developed based on an item analysis of the responses by 485 introductory psychology students (236 women and 249 men). The 10 masculine, 10 feminine, and 10 neutral items chosen for the short form were given to 60 subjects (28 women and 32 men), along with a measure of spatial performance (Piaget's water-level task). Reliabilities (by coefficient alpha) were .79, .77, and .75, for the masculine, feminine, and neutral activity subscales, respectively. As with the original scale, women had a greater preference than men for feminine activities, men had a greater preference than women for masculine activities, and women and men had an equal preference for neutral activities. Masculine activity preference was associated with better water-level performance, with the relationship significantly stronger for women (r=.50) than for men (r=.10). Uses for the questionnaire in research on sex-related differences in spatial performance are suggested.  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