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   5132篇
  免费   285篇
  国内免费   2篇
  2023年   41篇
  2022年   37篇
  2021年   76篇
  2020年   90篇
  2019年   141篇
  2018年   197篇
  2017年   228篇
  2016年   214篇
  2015年   144篇
  2014年   157篇
  2013年   556篇
  2012年   299篇
  2011年   312篇
  2010年   169篇
  2009年   201篇
  2008年   278篇
  2007年   259篇
  2006年   213篇
  2005年   181篇
  2004年   191篇
  2003年   200篇
  2002年   164篇
  2001年   73篇
  2000年   71篇
  1999年   57篇
  1998年   62篇
  1997年   51篇
  1996年   49篇
  1995年   43篇
  1994年   35篇
  1993年   38篇
  1992年   29篇
  1991年   31篇
  1990年   33篇
  1989年   23篇
  1988年   26篇
  1987年   23篇
  1986年   18篇
  1985年   36篇
  1984年   22篇
  1983年   40篇
  1982年   21篇
  1981年   25篇
  1980年   18篇
  1979年   26篇
  1977年   17篇
  1975年   16篇
  1973年   26篇
  1968年   20篇
  1967年   17篇
排序方式: 共有5419条查询结果,搜索用时 15 毫秒
61.
An experiment is reported which shows the effect of inspection of a curved line on the apparent curvature of a curved test line for a range of curvatures of both I and T lines. A second experiment extends the range of I curvatures, using only one T line, a straight line. The experiments showed both adaptation and repulsion components in the FAE.

An experiment by Kohler and Wallach which could not be reconciled with these results was repeated in the relevant part; the results were in agreement with the first experiment here and did not agree with those obtained by Kohler and Wallach.

An argument is presented that both adaptation and repulsion effects could be produced by a cell adaptation mechanism.  相似文献   
62.
Left and right halves of a visual display were covered with inducing fields (IFs) of different lightnesses. S’s monocular gaze moved over an irreversible route from a neutral Munsell target to a CO series through either the left- or right-side IFs. For the 16 Ss there were 8 different IFs, varying from light to dark. For each of three different gray targets Munsell CO choices varied directly with the lightness of the IFs through which the gaze was routed rather than with the lightness of the total presented display. A replication with modifications is also reported.  相似文献   
63.
64.
Recent studies have called for the abandonment of the relative-time-spent scale in task inventories. This recommendation is based on findings that the job profile created with the scale data is highly correlated with the profile created from a much simpler “Do you perform this task?” checklist. We examined this issue using 3 inventories and 42 jobs (N=2252). Profile correlations were computed on only the tasks actually performed by incumbents to avoid possibly inflated rs due to including irrelevant tasks. The specificity of task inventory items was proposed as an explanation for the high correlation between the two job profiles. Specificity of items was examined by looking at both the type (job duties versus tasks) and the amount (number of items in job profile and average number of items relevant to each job) of items used in the inventory. Correlations between time spent and checklist profiles were in the .80's and .90's regardless of the number of irrelevant tasks or the specificity of tasks. We agree with previous military research and conclude that the relative-time-spent scale has limited incremental utility beyond a dichotomous checklist.  相似文献   
65.
Edward O. Wilson 《Zygon》1990,25(3):245-262
Abstract. The sciences may be conceptualized as a hierarchy ranked by level of organization (e.g., many-body physics ranks above particle physics). Each science serves as an antidiscipline for the science above it; that is, between each pair, tense but creative interplay is inevitable. Biology has advanced through such tension between its subdisciplines and now can serve as an antidiscipline for the social sciences—for anthropology, for example, by examining the connection between cultural and biological evolution; for psychology, by addressing the nature of learning and the structure of the unconscious; for economics, by examining economically irrational behavior and by comparing economic activity in humans and other species. Sociology, concerned mainly with advanced literate societies, is relatively remote from the genetic basis of human social behavior. However, moving between biological and social levels of organization generates richness and points to new and unexpected principles.  相似文献   
66.
Humility training is conceptualized as an appropriate treatment for persons who occasionally describe themselves, but are most frequently described by others as overbearing, insensitive and deceitful. Procedures are outlined to identify unrecognized fears and improve interpersonal skills. Humility is presented as a counterpoint to assertiveness and aggression/anger control interventions.  相似文献   
67.
This investigation focused on the interrelationships among students' study activities, students' self-concept of academic ability ratings, students' academic achievement, and instructional practices in 12 high school biology courses. Using a framework derived from a previous investigation, course features were classified into those that appear to (a) place demands on, (b) support, or (c) compensate for student engagement in particular study activities. Students' study activities, self-concept of academic ability ratings, and achievement were measured with experimenter-developed instruments. Results are reported for (a) characteristics of instruments and course features, (b) relationships between central factors of the investigation, and (c) multi-level relationships between course features and student variables. Results at the student level indicated that self-concept of academic ability and, to a lesser extent, students' study activities were positively associated with student achievement. Students' self-concept of academic ability ratings were also linked to students' engagement in generative, proactive study activities. At the course level the supportive practices of providing challenging homework assignments and extensive feedback on student coursework were associated with student engagement in effortful, generative, proactive study activities. The provision of extensive feedback was also associated with high student achievement. Multi-level relationships were analysed using hierarchical linear modelling (HLM) analyses. These analyses revealed, for example, that in courses in which little or no feedback is given on homework assignments, the relationship between achievement and student engagement in diligent effort management activities was enhanced. Other HLM analyses were conducted to examine the mediating role of course features on the relationship between students' self-concept of academic ability and their study activities and achievement. For example, the presence of challenging course demands was associated with an enhancement of the relationship between self-concept of academic ability and achievement whereas the presence of instructor provisions (supports and compensations) designed to reduce course demands was associated with a reduction in this relationship.  相似文献   
68.
69.
This paper is concerned with the processing of informal arguments, that is, arguments involving probable truth. A model of informal argument processing is presented that is based upon Hample's (1977) expansion of Toulmin's (1958) model of argument structure. The model postulates that a claim activates an attitude, the two components forming a complex that in turn activates reasons. Furthermore, the model holds occurrence of the reason, or possibly the claim and the reason, activates values. Three experiments are described that provide support for the model.This research was supported by the Mellon Foundation and by the Office of Educational Research and Improvement of the Department of Education via an award for the Center for the Study of Learning to the Learning Research and Development Center. The contents of the paper are not necessarily the position of any of these organizations.  相似文献   
70.
To determine the frequency and correlates of nonsuicidal physically self-damaging acts in 12–14 year olds, a two stage epidemiologic survey with a self-administered questionnaire (N=3283) followed by a psychiatric interview of a subsample of the adolescents and their parents (N=444) was used. Prevalence estimates of interview validated nonsuicidal physically self-damaging acts were 2.46% in males and 2.79% in females. Significant relationships were found between nonsuicidal physically self-damaging acts and suicidal ideation, major depression and undesirable life events. Data suggest that physically self-damaging acts occur at substantial rates during early adolescence. The strong correlation between nonsuicidal self-destructive acts and both suicidal ideation and major depression clarifies prior conflicting reports in the literature and suggests that a history of self-damaging acts should be taken into consideration when evaluating for possible depression and suicide risk.  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