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   1542篇
  免费   81篇
  2023年   12篇
  2022年   31篇
  2021年   32篇
  2020年   47篇
  2019年   59篇
  2018年   61篇
  2017年   79篇
  2016年   88篇
  2015年   66篇
  2014年   69篇
  2013年   192篇
  2012年   107篇
  2011年   101篇
  2010年   69篇
  2009年   64篇
  2008年   84篇
  2007年   72篇
  2006年   66篇
  2005年   53篇
  2004年   46篇
  2003年   41篇
  2002年   43篇
  2001年   10篇
  2000年   11篇
  1999年   9篇
  1998年   10篇
  1997年   9篇
  1996年   7篇
  1995年   5篇
  1994年   6篇
  1993年   6篇
  1992年   2篇
  1991年   3篇
  1990年   5篇
  1989年   5篇
  1988年   4篇
  1987年   3篇
  1986年   10篇
  1985年   2篇
  1984年   3篇
  1983年   6篇
  1982年   7篇
  1981年   6篇
  1980年   3篇
  1979年   2篇
  1978年   2篇
  1977年   1篇
  1976年   2篇
  1975年   1篇
  1973年   1篇
排序方式: 共有1623条查询结果,搜索用时 31 毫秒
791.
792.
This article reports a longitudinal investigation that examines academic and social difficulties as predictors of depressive symptoms during middle childhood. Participants were 199 elementary school children (M=9.1 years) who were followed for 2 consecutive school years. In both years of the project, children completed a questionnaire assessing depressive symptoms and a peer nomination inventory assessing friendships and social standing. Grade point averages (GPAs) were obtained from a review of school records. Low GPAs were predictive of depressive symptoms, but this effect did not hold for children who had numerous friends. Similarly, children who had relatively few friends tended to experience depressive symptoms. However, the effect was attenuated for children with high GPAs. Taken together, the findings suggest that competencies in 1 domain can moderate the risks associated with difficulties in the other domain.  相似文献   
793.
The current study tested whether and why children of alcoholics (COAs) showed telescoped (adolescent) drinking initiation-to-disorder trajectories as compared with non-COAs. Using longitudinal data from a community-based sample, the authors confirmed through survival analyses that COAs progressed more quickly from initial adolescent alcohol use to the onset of disorder than do matched controls. Similar risks for telescoping were evident in COAs whose parents were actively symptomatic versus those whose parents had been previously diagnosed. Stronger telescoping effects were observed for COAs whose parents showed comorbidity for either depression or antisocial personality disorder. Both greater externalizing symptoms and more frequent, heavier drinking patterns at initiation failed to explain COAs' risk for telescoping, although externalizing symptoms were a unique predictor of telescoping. This risk for telescoping was also evident for drug disorders. These findings characterize a risky course of drinking in COAs and raise important questions concerning the underlying mechanisms and consequences of telescoping in COAs.  相似文献   
794.
This experiment aimed to expand previous findings on the development of mental number representation. We tested the hypothesis that children's familiarity with numbers is directly reflected by the shape of their mental number line. This mental number line was expected to be linear as long as numbers lay within the range of numbers children were familiar with. Five- to 9-year-olds (N=78) estimated the positions of numbers on an external number line and additionally completed a counting assessment mirroring their familiarity with numbers. A segmented regression model consisting of two linear segments described number line estimations significantly better than a logarithmic or a simple linear model. Moreover, the change point between the two linear segments, indicating a change of discriminability between numbers, was significantly correlated with children's familiar number range. Findings are discussed in terms of the accumulator model, assuming a linear mental representation with scalar variability.  相似文献   
795.
This paper describes a short-term longitudinal study of the relation between violent victimization in the community and peer rejection among 199 children (mean age = 9.02 years) attending two urban Los Angeles area elementary schools. We used a multi-informant approach to assess victimization by community violence, peer group victimization, peer rejection, and impairments in emotion regulation. These data were collected annually for two consecutive school years. Violent victimization in the community predicted later peer rejection after accounting for the effects of initial levels of peer rejection. Analyses indicated that this relation was mediated by deficient emotion regulation skills. In addition, we found evidence that victimization by community violence and peer rejection are reciprocally related over time. The developmental implications of these findings are discussed.  相似文献   
796.
A quantitative method is introduced for detecting and correcting artifactual signal changes in BOLD time series data arising from the magnetic field warping caused by motion of the articulatory apparatus when speaking aloud, with extensions to detection of subvocal articulatory activity during silent reading. Whole-head images allow the large, spike-like signal changes from the moving tongue and other components of the articulatory apparatus to be detected and localized in time, providing a measure of the time of vocalization onset, the vocalization duration, and also an estimate of the magnitude and shape of the signal change resulting from motion. Data from brain voxels are then examined during the vocalization period, and statistical outliers corresponding to contamination from articulatory motion are removed and replaced by linear interpolation from adjacent, uncontaminated data points. This quantitative approach to cleansing brain time series data of articulatory-motion-induced artifact is combined with a pre-scanning training regimen that reduces gross head movement during reading aloud to the levels observed during reading silently, which can be corrected with available image registration techniques. The combination of quantitative analysis of articulatory motion artifacts and pre-scanning training makes possible a much wider range of tasks involving overt speech than are currently being used in fMRI studies of language and cognition, as well as characterization of subvocal movements of the articulatory apparatus that are relevant to theories of reading skill, verbal rehearsal in working memory, and problem solving.  相似文献   
797.
Certain cultural customs and practices are viewed as abhorrent by many people, yet contemporary American counselors rarely criticize any specific culture. In this article, the authors explore why counselors abstain from such criticism. Furthermore, the authors demonstrate that universalism, often regarded as a politically incorrect and an academically archaic philosophy, is manifestly prevalent within the world's religious and political realms, as well as within the counseling profession. The authors assert that universalism should be prevalent within the counseling profession and that it can be integrated with multicultural principles. Finally, the authors suggest a procedure for identifying universal principles and practices.  相似文献   
798.
Bubka A  Bonato F  Palmisano S 《Perception》2008,37(5):704-711
When stationary observers view an optic-flow pattern, visually induced self-motion perception (vection) and a form of motion sickness known as simulator sickness (SS), can result. Previous results suggest that an expanding flow pattern leads to more SS than a contracting pattern. Sensory conflict, a possible cause of SS, may be more salient when an expanding optic-flow pattern is viewed. An experiment was conducted to test if a more salient sensory conflict accompanying expanding flow patterns might inhibit vection. Participants (n = 15) viewed a pattern of blue squares, either steadily expanded or contracted, on a large rear-projection screen. Vection onset and magnitude were measured for 30 s with a computer-interfaced slide device. Vection onset was significantly faster, and vection magnitude stronger, when a contracting pattern was viewed. We propose that our extensive experience with forward self-motion may form a neural expectancy (exposure-history) about the sensory inputs which typically accompany expanding flow. However, since backward self-motion is less common, there may be a weaker exposure-history for contracting flow, and as a result these patterns generate less salient sensory conflict and subsequently less vection.  相似文献   
799.
Factors correlated with suicidal behavior in a predominately Alaska Native region of Alaska are described, and the correlates relating to fatal and nonfatal suicide behaviors in this indigenous population are distinguished. Suicide data from the region (1990-2001) were aggregated and compared to 2000 U.S. Census Data using chi-squared tests. Multivariable logistic regression was used to identify predictors of suicide behaviors. Suicidal behaviors were significantly more common among single, unemployed Alaska Natives who had not completed high school. In multivariable analysis, male sex, age > or = 25 years, firearms, and substance abuse history were each associated with suicide death.  相似文献   
800.
In order to rebut G. E. Moore’s open question argument, ethical naturalists adopt a theory of direct reference for our moral terms. T. Horgan and M. Timmons have argued that this theory cannot be applied to moral terms, on the ground that it clashes with competent speakers’ linguistic intuitions. While Putnam’s Twin Earth thought experiment shows that our linguistic intuitions confirm the theory of direct reference, as applied to ‘water’, Horgan and Timmons devise a parallel thought experiment about moral terms, in order to show that this theory runs against our linguistic intuitions about such terms. My claim is that the Horgan–Timmons argument does not work. I concede that their thought experiment is a good way to test the applicability of the theory of direct reference to moral terms, and argue that the upshot of their experiment is not what they claim it is: our linguistic intuitions about Moral Twin Earth are parallel to, not different from, our intuitions about Twin Earth.
Andrea ViggianoEmail:
  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