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   8337篇
  免费   156篇
  国内免费   9篇
  2020年   52篇
  2019年   59篇
  2018年   221篇
  2017年   181篇
  2016年   267篇
  2015年   151篇
  2014年   109篇
  2013年   465篇
  2012年   416篇
  2011年   431篇
  2010年   117篇
  2009年   122篇
  2008年   182篇
  2007年   175篇
  2006年   174篇
  2005年   1437篇
  2004年   774篇
  2003年   552篇
  2002年   241篇
  2001年   112篇
  2000年   86篇
  1999年   85篇
  1998年   82篇
  1997年   47篇
  1996年   55篇
  1995年   50篇
  1994年   59篇
  1992年   78篇
  1991年   109篇
  1990年   106篇
  1989年   91篇
  1988年   65篇
  1987年   88篇
  1986年   75篇
  1985年   69篇
  1984年   56篇
  1983年   60篇
  1982年   46篇
  1981年   48篇
  1979年   70篇
  1978年   54篇
  1977年   44篇
  1975年   68篇
  1974年   66篇
  1973年   61篇
  1972年   53篇
  1971年   49篇
  1970年   44篇
  1968年   43篇
  1967年   45篇
排序方式: 共有8502条查询结果,搜索用时 15 毫秒
151.
152.
The present study reports on a clinical instrument designed for assessing self-efficacy in alcoholics. In contrast to studies that construct general measures, it was proposed that taking an individualized approach to assessment might offer an effective methodology. Thirty-four alcoholics in an outpatient, behaviorally oriented treatment program participated as subjects. During therapy, an Individualized Self-Efficacy Survey (ISS) was developed for each subject. The ISS was developed by (a) administering the Drinking Patterns Questionnaire (DPQ) to identify important problem areas (e.g., work, children, marital) and specific drinking antecedents and (b) constructing a 15-item scale using each drinker's most important cues. The utility of having clients choose their own items was supported by finding a significant relationship between problem areas identified as important on the DPQ and the areas reported as surrounding relapse. ISS ratings were reflective of efficacy changes during treatment, while posttreatment ISS scores were predictive of subsequent relapse. Situation-specific prediction of relapse was not found. The advantages of this methodology for clinical use are discussed, while general directions for future research are suggested.  相似文献   
153.
As the principle of timing or opportunity,kairos serves both as a powerful theme within technological discourse and as an analytical concept that explains some of the suasory force by which such discourse maintains itself and its position in our culture. This essay makes a case for a rhetoric of technology that is distinct from the rhetoric of science and illustrates the value of the classical vocabulary for understanding contemporary rhetoric. This case is made by examining images and models of technological change that underlie and justify the thematizations ofkairos that appear in so much technological discourse and by exploring the phenomenon of technological forecasting, in which the characterization and construction of moments in the present are crucial to the projection of the future. One example of forecasting is examined in detail: the Japanese Fifth Generation computer project, which illustrates the twin themes of opportunity and threat.  相似文献   
154.
This paper addresses a problem in reporting scientific research. The problem is how to distinguish between justifiable and unjustifiable data selection. Robert Millikan is notorious for an infamous remark that he used all his data when in fact he had used a selection. On this basis he has been accused of fraud. There is a tension here — historians and his defenders see his selection as understandable and legitimate, while current statements about the Responsible Conduct of Research imply his selection was illegitimate. This paper discusses two main issues that arise in assessing his conduct, whether he was intentionally misleading and whether he actually did mislead the scientific community about some facts of nature. It is argued that he was not intentionally misleading, and that it is unlikely that he misled the scientific community.  相似文献   
155.
In two experiments, a concurrent discrimination paradigm was used to study the effects of visual attention on psychophysical judgments and the consistency of these effects with a sample-size model in which attention influences the variance of the internal representation used to make psychophysical judgments. Two pairs of lines were presented simultaneously—one on each side of fixation—and subjects had to indicate for each pair separately whether or not the lines had the same length. Attention was manipulated by instructing subjects to pay 100%, 75%, 50%, 25%, or 0% of their attention to the discrimination on one side, with the complementary amount of attention to the other side. In the first experiment, the relationship between attention and discrimination accuracy was consistent with the sample-size model both when attentional allocation varied from trial to trial and when it varied between blocks, and the relationship held over more widely varying attentional allocations than had previously been studied. In addition, discriminations were more accurate overall with varied than with blocked attentional allocation, suggesting that the two types of allocation do not merely differ in the degree to which attention is focused. The second experiment examined the effects of attentional allocation and stimulus variance, the latter being manipulated by randomly incrementing or decrementing line lengths. These manipulations had additive effects on total Thurstonian variance, and a version of the samplesize model gave an excellent quantitative fit to the obtained results. Besides supporting the samplesize model, the results of Experiment 2 suggest that criterion variance is at least as large as sensory variance and that criterion but not sensory variance increases with stimulus variance.  相似文献   
156.
Five experiments reexamined color aftereffects contingent on the semantic properties of text (Allan, Siegel, Collins, & MacQueen, 1989). The influence of different assessment techniques and the effect of eye movements and overlapping contour information on the induction of color aftereffects by word and nonword letter strings were determined. Experiment 1 showed that no aftereffect was found when a traditional method of assessing color aftereffects was used. Experiments 2 and 4 demonstrated color aftereffects forboth words and nonwords, but only when subjects fixated the same locus during induction and testing and only when assessed with the technique described by Allan et al. (1989). If, however, eye movements were made during induction, no color aftereffect was obtained (Experiment 3). Induction to nontext patterns with properties similar to those of text but with fewer overlapping contours resulted in a strong color aftereffect (Experiment 5). These results suggest that the color aftereffect contingent on text is very weak and is not dependent on semantic factors, but that it is a product of induction to local color and orientation information.  相似文献   
157.
158.
Co-morbidity of alcohol and substance with the spectrum of other psychiatric diagnoses is examined with specific emphasis on diagnostic indicators for anxiety and mood disorders. Diagnostic issues for the chemically dependent person are examined with the context of borderline personality disorder, schizophrenia and other psychiatric disorders. Clinical research related to the dually-diagnosed patient is explored  相似文献   
159.
Pigeons were trained to peck a key on a variable-interval 2-min schedule of food reinforcement. Prior to each session, either 2.0 mg/kg methadone (n = 3), 3.0 mg/kg cocaine (n = 4), or 5.6 mg/kg cocaine (n = 2) was administered. When each pigeon's rate of pecking was stable, a range of doses of the training drug and saline were administered prior to 20-min extinction sessions separated by at least four training sessions. Rate of pecking during these extinction tests was generally an increasing function of dose, with the lowest rates obtained following saline and low doses and the highest rates obtained following doses near the training doses. Dose functions from pigeons trained with 5.6 mg/kg cocaine were steeper than those from pigeons trained with 3.0 mg/kg cocaine. Pigeons trained with methadone or 3.0 mg/kg cocaine were then given discrimination training, in which food reinforcement followed drug administration and 20-min extinction sessions followed saline administration. Rates of pecking under these conditions quickly diverged until near-zero rates were obtained following saline and high rates were obtained following drug. Discrimination training steepened dose functions for the training drugs, and the effects of several other substituted drugs depended on the pharmacology of the training drug. The pigeons trained with 5.6 mg/kg cocaine were tested with d-amphetamine, methadone, and morphine prior to discrimination training. d-Amphetamine increased rates dose dependently, and methadone and morphine did not. The results suggest that discriminative control by methadone and cocaine was established without explicit discrimination training.  相似文献   
160.
The Conners' Parent Rating Scale (CPRS) is a popular research and clinical tool for obtaining parental reports of childhood behavior problems. The present study introduces a revised CPRS (CPRS-R) which has norms derived from a large, representative sample of North American children, uses confirmatory factor analysis to develop a definitive factor structure, and has an updated item content to reflect recent knowledge and developments concerning childhood behavior problems. Exploratory and confirmatory factor-analytic results revealed a seven-factor model including the following factors: Cognitive Problems, Oppositional, Hyperactivity-Impulsivity, Anxious-Shy, Perfectionism, Social Problems, and Psychosomatic. The psychometric properties of the revised scale appear adequate as demonstrated by good internal reliability coefficients, high test-retest reliability, and effective discriminatory power. Advantages of the CPRS-R include a corresponding factor structure with the Conners' Teacher Rating Scale—Revised and comprehensive symptom coverage for attention deficit hyperactivity disorder (ADHD) and related disorders. Factor congruence with the original CPRS as well as similarities with other parent rating scales 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