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   7110篇
  免费   134篇
  国内免费   188篇
  7432篇
  2018年   21篇
  2017年   27篇
  2016年   26篇
  2015年   37篇
  2014年   29篇
  2013年   35篇
  2012年   579篇
  2011年   618篇
  2010年   157篇
  2009年   106篇
  2008年   480篇
  2007年   499篇
  2006年   459篇
  2005年   407篇
  2004年   371篇
  2003年   298篇
  2002年   297篇
  2001年   188篇
  2000年   227篇
  1999年   81篇
  1998年   58篇
  1997年   23篇
  1996年   41篇
  1995年   23篇
  1994年   76篇
  1993年   87篇
  1992年   92篇
  1991年   97篇
  1990年   92篇
  1989年   93篇
  1988年   104篇
  1987年   119篇
  1986年   86篇
  1985年   114篇
  1984年   110篇
  1983年   133篇
  1982年   84篇
  1981年   83篇
  1980年   73篇
  1979年   78篇
  1978年   63篇
  1966年   48篇
  1965年   131篇
  1964年   104篇
  1963年   127篇
  1962年   54篇
  1958年   76篇
  1957年   59篇
  1956年   44篇
  1953年   9篇
排序方式: 共有7432条查询结果,搜索用时 0 毫秒
241.
We hypothesized that semester goal attainment provides a route to short-term psychological growth. In an attempt to enhance this process, we randomly assigned participants to either a goal-training program or to a control condition. Although there were no main effects of program participation on later goal attainment, important interactions were found. Consistent with a "prepared to benefit" model, participants already high in goal-based measures of personality integration perceived the program as most useful and benefited the most from the program in terms of goal attainment. As a result, they became even more integrated and also increased in their levels of psychosocial well-being and vitality. Implications for theories of short-term growth and positive change are discussed, as is the unanswered question of how to help less-integrated persons grow.  相似文献   
242.
The authors examined age differences in perceived coping resources and satisfaction with life across 3 older-adult age groups (45-64, 65-74, and 75 years and older). The 98 participants represented healthy, socially active, community-residing adults. Group comparisons were made on 12 individual coping scales, and an overall coping resource effectiveness score was computed. No significant differences were found for 11 of the coping resources or for overall coping resource effectiveness. Similar consistencies in life satisfaction were found across the 3 age groups. The findings indicate that (a) for healthy adults, the oldest old cope at least as effectively as their younger counterparts, despite their likelihood of encountering increased levels of stress; and (b) psychologically, old age may be viewed as a time of resilience and fortitude.  相似文献   
243.
This study examined how well reality was reproduced in several conditions of virtual reality, by mutually comparing the perception of distance in actual 3-dimensional space and 3-dimensional video-recorded space. Apparent distances in both indoor and outdoor situations were estimated by 10 adolescents. Analysis showed that relations between apparent distance and physical distance in the actual spaces both in indoor and outdoor situations are described by 0.95 and 1.01 power exponents, respectively. On the other hand, the underestimations of the apparent distance are shown in the 3-dimensional video-recorded and the virtual reality spaces both in indoor and outdoor situations whose exponents ranged from .53 to .80.  相似文献   
244.
This study describes a method of modeling human trunk and whole body backward bending and suggests a possible neural control strategy. The hypothesis was that the control system can be modeled as a linear feedback system, in which the torque acting at a given joint is a function of the state variables (angular positions and angular velocities). The linear system enabled representation of the feedback system by a gain matrix. The matrix was computed from the kinematics recorded by a movement analysis system and from the joint torques calculated by inverse dynamics. To validate the control model, a comparison was made between the angular kinematics yielded by the model and the experimental data. Moreover, for all subjects, the same relationships between feedback coefficients were found although gain values were different. The study showed that the feedback system is an appropriate model of the strategy from performing an accurate controlled trunk or whole body backward bending in the sagittal plane.  相似文献   
245.
Personality, mental distress, and risk perception were assessed in (a) cases of multiple chemical sensitivity (MCS; n = 17), (b) chemically intolerant toxic encephalopathy cases (TE), type 2A (n = 31) and 2B (n = 26), and (c) healthy referents (n = 200). MCS cases showed elevated mental distress scores on the Depression, Interpersonal Sensitivity, Global Severity Index, and Somatization scales in the Symptom Checklist 90 (SCL-90). In the Karolinska Scales of Personality (KSP) the MCS group showed an elevation only on the Psychasthenia scale. Both TE groups showed elevations across the KSP anxiety scales Muscular Tension, Psychasthenia, and Somatic Anxiety. TE type 2B subjects also showed elevations on the Irritability and Indirect Aggression scales. However, neither MCS nor TE groups showed deviating personality characteristics in the Meta Contrast Technique test. Similarly, none of the groups deviated from referents in a risk perception inventory.  相似文献   
246.
Cognitive deficits in major depression   总被引:4,自引:0,他引:4  
Major depression is a mood disorder that is often accompanied by the impairment of cognitive functions. Although suggestive, the large range of existing neuropsychological, neuropsychiatric, and, lately, neuroimaging investigations have not yet given a consistent picture of the psychological and biological disturbances involved in this psychiatric disorder. The present study of the cognitive functions in depression was part of an extensive investigation, including neuropsychological testing, psychiatric examination, and neuroimaging. A representative sample of 40 severely depressed hospitalized patients and a group of 49 closely matched control subjects were tested with an extensive neuropsychological test battery. Results, corrected for various confounding factors, confirmed the current notion that depressed patients suffer from wide-spread cognitive impairments. The group analysis did not allow any hypothesis on a possible pattern to the dysfunctions, but heterogeneity in the test performances calls for further analysis of the data in patient subgroups in relation to neuroimaging results.  相似文献   
247.
This paper discusses several factors affecting the development of children prenatally exposed to drugs. In the "first generation" of research in this field a main factor model of disease formed the basis for a belief in the feasibility of detecting the direct pharmacological or teratogenic effects of drug exposure on long-term child development. However, the clustering of confounding variables has constituted a major problem in identifying these effects. In the last few years a "second generation" of research in this field has emerged, and investigators have moved beyond simple main-effect models. The importance of controlling for confounding variables has been underscored. However, prenatal substance exposure is still often studied within a teratology model where the main goal is the search for unique effects of a specific drug or substance. Based on this review it is suggested that an appropriate model for understanding the development of drug-exposed children cannot be based on a main-effect perspective. Rather, such a model must evolve from a contextual perspective, and it is suggested that a transactional model, where both potential risk factors and protective factors are considered, should replace the traditional teratology model in this field.  相似文献   
248.
The purpose of the study was to investigate cultural changes in a Norwegian airline company over a time span of 10 years. A questionnaire including parameters characterizing culture was administered to air crews in 1986 (n = 137) and in 1996 (n = 50). The performance part of a simulator study in 1996 indicated a significant reduction in operational failures compared with the 1986 study. The data further demonstrated significant changes in cultural variables, such as reduced Dominance and Masculinity, and improved Social climate and Communication. The direction of change in scores on the cultural variables corresponded with the principles on which the remedial actions were based.  相似文献   
249.
This study examined empathy and reciprocity as explanations for why people comply with requests for help. Participants (35 male and 62 female) imagined being asked for money by a person who had locked keys in a car and then reported how likely they would he to comply with such a request, whether they had previously locked their keys in their car (empathy), and, if so, whether they had been helped (reciprocity). In support of the explanation based on empathy, people who reported previously locking their keys in their cars indicated being more likely to comply.  相似文献   
250.
The present study addresses the question of how practice in expressing the content to be conveyed in a specific situation influences speech production planning processes. A comparison of slips of the tongue in Japanese collected from spontaneous everyday conversation and those collected from largely preplanned conversation in live-broadcast TV programs reveals that, although there are those aspects of speech production planning that are unaffected by practice, there are various practice effects, most of which can be explained in terms of automatization of the processing of content, resulting in shifts in the loci of errors.  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