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   3273篇
  免费   173篇
  国内免费   2篇
  3448篇
  2023年   22篇
  2021年   37篇
  2020年   67篇
  2019年   85篇
  2018年   86篇
  2017年   114篇
  2016年   108篇
  2015年   84篇
  2014年   88篇
  2013年   343篇
  2012年   145篇
  2011年   166篇
  2010年   121篇
  2009年   118篇
  2008年   126篇
  2007年   128篇
  2006年   129篇
  2005年   104篇
  2004年   105篇
  2003年   119篇
  2002年   109篇
  2001年   58篇
  2000年   49篇
  1999年   44篇
  1998年   38篇
  1997年   41篇
  1996年   44篇
  1995年   36篇
  1994年   31篇
  1993年   34篇
  1992年   38篇
  1991年   37篇
  1990年   45篇
  1989年   26篇
  1988年   38篇
  1987年   20篇
  1986年   24篇
  1985年   35篇
  1984年   17篇
  1983年   41篇
  1982年   29篇
  1981年   26篇
  1980年   19篇
  1979年   26篇
  1977年   18篇
  1976年   18篇
  1975年   17篇
  1973年   28篇
  1968年   22篇
  1967年   17篇
排序方式: 共有3448条查询结果,搜索用时 0 毫秒
151.
152.
The absence or diminution of light is potentially an anxiety-arousing situation for, perhaps, all of us. Even a cursory look at the origin myths of many cultures reveals the chaotic, destructive, and dangerous aspects of darkness. Additionally, language reflects the same qualities metaphorically and symbolically. Developmentally, the arrival of the darkness of evening potentially signals object loss and ego regression. But factors other than ubiquitous references to a consideration of light and darkness are relevant. Can it be that we are all at least prone to depression due in part to this factor? Questions regarding possible biological causes of depression are perhaps unanswerable at this time. Is the seratonin level really associated with depression and light deprivation? Research is as yet inconclusive. If a relationship exists, another question must be asked: Will certain psychological situations affect a person's seratonin production? The answer to this question of how depression is associated with biological causes is certainly beyond the scope of this paper. Yet the preceding case history reveals at least some psychological causes of depression that were initially seen as biologically based. The SAD proponents would have treated Mr. B with light therapy. The quick solution of light therapy, based on a shaky theoretical base and lacking sturdy research, has too often replaced the psychoanalytic approach. In all too many situations psychoanalysts are being replaced by lightbulbs.  相似文献   
153.
This article reviews relevant literature as to the labor pool of qualified individuals with disabilities and employment in information technology (IT) sector jobs. First, the article reviews the empirical literature on barriers to employment in IT for persons with disabilities. The examination then is extended to studies of barriers to employment for individuals with disabilities in other employment sectors. Findings illustrate the limited experiences that IT and non-IT companies have in employing and accommodating employees with disabilities. Implications are discussed for enhancing the employment of qualified workers with disabilities in IT through research, education, training, and mentoring programs.  相似文献   
154.
The objective of this research was to test substance-related and non-substance-related psychiatric disorders as predictors of attempted suicide among adolescents. Ninety-six psychiatrically disordered suicide attempters were matched one-to-one to 96 psychiatrically disordered non-attempters on age, race, gender, and the presence/absence of major depression. Conditional logistic regression was used to test psychiatric risk factors for their power to predict attempted suicide among adolescents. Bipolar disorder, cocaine use disorders, and conduct disorder were found to be predictive of attempted suicide in univariate testing. Bipolar disorder, inhalant use disorders, cocaine use disorders, and hallucinogen use disorders were found to be predictive of attempted suicide, after adjusting for all other covariates. Loglinear analyses revealed high odds ratios associated with the comorbidities of alcohol use disorder with conduct disorder and drug use disorders with conduct disorder in both groups. Higher rates of cocaine use disorder/conduct disorder, hallucinogen use disorder/conduct disorder, and alcohol use disorder/ conduct disorder were found among suicide attempters. Evaluation of these particular comorbid conditions should be part of the adolescent suicide risk assessment.  相似文献   
155.
Although memory for actual events tends to be forgotten over time, memory for misinformation tends to be retrieved at a stable rate over long delays or at a rate greater than that found immediately after encoding. To examine whether source monitoring errors contribute to this phenomenon, two experiments investigated subjects' memory for the source of misinformation at different retention intervals. Subjects viewed a slide presentation, read a narrative containing misinformation, and, either 10 minutes or 1 week later, completed a recognition test about details seen in the slides and about the source of these details. After the longer retention interval in both experiments, participants were more likely to agree that they had seen misleading information and were also more likely to incorrectly associate the misinformation with the slide event. Theoretical implications of these findings are considered.  相似文献   
156.
In this study we assessed habituation and sensitization of the acoustic startle response (ASR) to discern whether intense, inescapable stress affects nonassociative learning differently in male and female rats. Rats were inescapably stressed 2 hours per day over 3 consecutive days. ASR magnitudes were measured at several times post-stress (1, 4, 8, and 15 days after cessation). Females generally showed greater ASR magnitudes (compared to males), but both sexes exhibited short and long-term habituation across the testing days. ASR magnitudes were only affected by stress in male subjects. The effect in males was an increase in short-term sensitization of the ASR on post-stress day-4. The results suggest that stressed males and females react differently to ASR testing, in that stress males appear to develop an exaggerated ASR response over repeated test sessions due to short-term sensitization. The source of the short-term sensitization is discussed with regards to possible stress-induced enhanced contextual learning during ASR testing on post-stress day-1.  相似文献   
157.
A model of dual attitudes   总被引:66,自引:0,他引:66  
When an attitude changes from A1 to A2, what happens to A1? Most theories assume, at least implicitly, that the new attitude replaces the former one. The authors argue that a new attitude can override, but not replace, the old one, resulting in dual attitudes. Dual attitudes are defined as different evaluations of the same attitude object: an automatic, implicit attitude and an explicit attitude. The attitude that people endorse depends on whether they have the cognitive capacity to retrieve the explicit attitude and whether this overrides their implicit attitude. A number of literatures consistent with these hypotheses are reviewed, and the implications of the dual-attitude model for attitude theory and measurement are discussed. For example, by including only explicit measures, previous studies may have exaggerated the ease with which people change their attitudes. Even if an explicit attitude changes, an implicit attitude can remain the same.  相似文献   
158.
The rapid detection of facial expressions of anger or threat has obvious adaptive value. In this study, we examined the efficiency of facial processing by means of a visual search task. Participants searched displays of schematic faces and were required to determine whether the faces displayed were all the same or whether one was different. Four main results were found: (1) When displays contained the same faces, people were slower in detecting the absence of a discrepant face when the faces displayed angry (or sad/angry) rather than happy expressions. (2) When displays contained a discrepant face people were faster in detecting this when the discrepant face displayed an angry rather than a happy expression. (3) Neither of these patterns for same and different displays was apparent when face displays were inverted, or when just the mouth was presented in isolation. (4) The search slopes for angry targets were significantly lower than for happy targets. These results suggest that detection of angry facial expressions is fast and efficient, although does not "pop-out" in the traditional sense.  相似文献   
159.
160.
Analysis of oral and written discourse suggested differing cognitive demands for modes of expression. Verbal samples were provided by 8 adolescents with closed head injury (CHI) and 8 controls. A generation task using a picture stimulus was the basis for discourse. Eight measures [productivity, efficiency, semantic ties (lexical, incomplete, elliptical), maze use, coherence (global, local)] were utilized. A covariate model consisting of group membership (CHI vs control), executive functioning and working memory helps to explain variance in the discourse skills of adolescents with CHI.  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