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   5495篇
  免费   278篇
  国内免费   5篇
  5778篇
  2024年   10篇
  2023年   62篇
  2022年   90篇
  2021年   105篇
  2020年   151篇
  2019年   143篇
  2018年   273篇
  2017年   250篇
  2016年   237篇
  2015年   150篇
  2014年   169篇
  2013年   721篇
  2012年   409篇
  2011年   416篇
  2010年   252篇
  2009年   173篇
  2008年   320篇
  2007年   259篇
  2006年   232篇
  2005年   220篇
  2004年   130篇
  2003年   135篇
  2002年   131篇
  2001年   62篇
  2000年   81篇
  1999年   54篇
  1998年   28篇
  1997年   24篇
  1996年   24篇
  1995年   30篇
  1994年   19篇
  1993年   24篇
  1992年   33篇
  1991年   24篇
  1990年   28篇
  1989年   25篇
  1988年   28篇
  1987年   19篇
  1986年   11篇
  1985年   13篇
  1984年   16篇
  1983年   13篇
  1979年   16篇
  1978年   11篇
  1976年   13篇
  1974年   10篇
  1971年   10篇
  1970年   10篇
  1968年   11篇
  1965年   10篇
排序方式: 共有5778条查询结果,搜索用时 8 毫秒
201.
The purpose of this study was to determine whether an association exists between neuropsychological deficits and conduct disorder (CD) with and without concurrent attention-deficit–hyperactivity disorder (ADHD). In addition, we explored the differential neuropsychological performance of aggressive and nonaggressive CD adolescents and the combined effect of this behavioral status and ADHD on performance. Fifty-nine adolescents (mean age of 15.4 years) who met the criteria for CD were compared with 29 controls comparable in age, gender, and socioeconomic status. A neuropsychological battery of current tests measuring executive functions and a battery of language tests were used in the study. Multivariate analyses showed that, compared with controls, CD adolescents had significantly lower verbal skills but did not differ on executive function measures. However, the lower verbal performance of CD adolescents is not explained by the existence of a CD subgroup with concomitant ADHD or aggressiveness. The study confirms with a sample of CD adolescents the association between verbal deficits and antisocial behavior when socioeconomic status is controlled. Our results also demonstrate that CD per se can be a sufficient condition for such deficits.  相似文献   
202.
203.
Ratings of familiarity and pronounceability were obtained from a random sample of 199 surnames (selected from over 80,000 entries in the Purdue University phone book) and 199 nouns (from the Ku?era-Francis, 1967, word database). The distributions of ratings for nouns versus names are substantially different: Nouns were rated as more familiar and easier to pronounce than surnames. Frequency and familiarity were more closely related in the proper name pool than the word pool, although both correlations were modest. Ratings of familiarity and pronounceability were highly related for both groups. A production experiment showed that rated pronounceability was highly related to the time taken to produce a name. These data confirm the common belief that there are differences in the statistical and distributional properties of words as compared to proper names. The value of using frequency and the ratings of familiarity and pronounceability for predicting variations in actual pronunciations of words and names are discussed.  相似文献   
204.
Laraudogoitia  Jon Pérez 《Synthese》1999,119(3):313-323
In Pérez Laraudogoitia (1996), I introduced a simple example of a supertask that involved the possibility of spontaneous self-excitation and, therefore, of a particularly interesting form of indeterminism in classical dynamics. Alper and Bridger (1998) criticised (among other things) this result. In the present article, I answer their criticisms. In what follows I assume familiarity both with Pérez Laraudogoitia (1996) and Alper and Bridger’s subsequent article. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
205.
17 subjects diagnosed with schizophrenia and having auditory hallucinations in their case history were compared with 15 control subjects in an experiment on perceptual restoration. A tone pattern was presented, then interrupted by noise, under conditions such that the tone pattern could be heard as going on continuously (restoration). A series of 16 stimuli with a distractor of varying amplitude (noise) were presented. Healthy controls reliably reported restoration in Presentations 9 and 10. Four schizophrenics reported no restoration at all. Three of them reported restoration earlier than controls, and four others reported it later than controls and continued to report the phenomenon after a point at which no healthy controls did. Six other presented an irregular pattern of response to the phenomenon. The results are discussed with respect to the neurophysiological functioning of the auditory pathway and schizophrenic symptoms.  相似文献   
206.
Analysis of 1998 statistics for individual performance in the PGA European Tour yielded significant differences between some shot-making skills (drive distance, total driving, greens in regulation, and sand saves) between the top 10 and bottom 10 money winners, replicating (with partially different results) a result found for the 1995 American PGA Tour by Engelhardt.  相似文献   
207.
Previous research suggests that early mentoring relationship (MR) closures may have harmful consequences for the health and well‐being of youth participating in community‐based mentoring programs. However, knowledge of the factors that lead some MRs to close early has been slow to emerge. This study examined patterns and correlates of early versus on‐time MR closures among 569 youth participating in Big Brothers Big Sisters community mentoring programs. Thirty‐four percent of youth experienced an early MR closure prior to the end of the program's 12 month period of commitment. The probability of closure was highest at 12 months into the MR. Early closures were positively associated with youth gender (girls), behavioral difficulties, and match determination difficulties. Early and on‐time closures were associated with youth extrinsic motives for joining the program. Early MR closures were negatively associated with youth perceptions of parent emotional support, parent social support, high quality MR, weekly contact in MR, and parent support of the MR. Implications for programming are discussed.  相似文献   
208.
Resumen

En el presente trabajo se han empleado las medidas cronométricas de Tiempo de Inspección (TI) y Tiempo de Reacción (TR) para estudiar los efectos de las diferencias individuales en extroversion sobre una tarea de discriminación perceptual. Para ello se utilizaron dos grupos de sujetos que habían obtenido puntuaciones máximas y mínimas en la dimensión Extraversión del Test EPI de H. J. Eysenck. Se postuló que los extrovertidos obtendrían un TI más corto que los introvertidos y asimismo un TR también más corto, de acuerdo a los modelos de Brebner (1980) y Tous (1986). Los resultados indicaron que si bien existieron diferencias entre extrovertidos e introvertidos en cuanto a las medidas cronométricas, estas dit erencias dependieron del uso diferencial de estrategias de resolver la tarea que fueron utilizadas por estos sujetos.  相似文献   
209.
The goal of the study was to examine the dimensionality of the Career Decision Self-Efficacy Scale Short Form (CDSES-SF, Betz et al. 1996). Integrating several previous findings from different cultures, we found that the bifactor structure of the CDSES-SF on a Hungarian sample of 649 respondents showed the best model fit. This structure includes a general CDSE factor covering 15 items and the original five specific factors (self-appraisal, occupational information, goal selection, planning, and problem solving) covering three items each. This short form of CDSES shows an acceptable model fit and appropriate reliability in terms of the Cronbach’s alpha and omega values. Regarding career decision self-efficacy, a large proportion of variance was explained by the general factor and to a smaller extent by the specific factors. These results can be considered as a first step in resolving the paradox of the dimensionality of CDSES-SF.  相似文献   
210.
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