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   3862篇
  免费   29篇
  国内免费   2篇
教育   2804篇
科学研究   371篇
各国文化   75篇
体育   196篇
综合类   2篇
文化理论   45篇
信息传播   400篇
  2021年   24篇
  2020年   32篇
  2019年   51篇
  2018年   74篇
  2017年   74篇
  2016年   85篇
  2015年   46篇
  2014年   56篇
  2013年   997篇
  2012年   48篇
  2011年   58篇
  2010年   51篇
  2009年   65篇
  2008年   63篇
  2007年   54篇
  2006年   66篇
  2005年   45篇
  2004年   54篇
  2003年   47篇
  2002年   46篇
  2001年   54篇
  2000年   64篇
  1999年   53篇
  1998年   55篇
  1997年   47篇
  1996年   50篇
  1995年   55篇
  1994年   58篇
  1993年   53篇
  1992年   65篇
  1991年   57篇
  1990年   46篇
  1989年   46篇
  1988年   50篇
  1987年   53篇
  1986年   49篇
  1985年   59篇
  1984年   42篇
  1983年   41篇
  1982年   61篇
  1981年   36篇
  1980年   50篇
  1979年   50篇
  1978年   36篇
  1977年   29篇
  1976年   38篇
  1975年   39篇
  1974年   26篇
  1973年   29篇
  1970年   23篇
排序方式: 共有3893条查询结果,搜索用时 15 毫秒
151.
152.
153.
Abstract

The modernisation of potato production in the Ecuadorian highlands is related to an intensive use of pesticides. In this context, by means of ethnographic methodologies and discourse analysis tools, this study was aimed to determine the influence of household arrangements, local institutions and social differentiation in the management of potato production and pesticide use. Potato production involves all household members and generates occupational risks, but also household-level accidents. This study has determined that children and teenagers form the group most vulnerable to intoxication with pesticides. Four social dimensions that integrate pesticides in the local social dynamics were determined: health-beliefs, gender identity, social identity, and economical progress reliance by means of potato production. Intense potato production and comoditisation of nature is contributing to a progressive social stratification, which is causing a group of peasant households to emerge as the poorest group and vulnerable to occupational risks by chronic pesticide exposure.  相似文献   
154.
155.
Audio Instruction tapes are described as a form of semi-automated learning whose potential previously has not been realized. Students do not listen to these tapes; they work along with them. These tapes are not lectures. They do not substitute for the teacher. They require the teacher and the class situation for enforcement of learning. This article describes the tapes available for applied statistics and explains how they are used.  相似文献   
156.
The habituation of locomotor activity across repeated exposures to a novel maze was studied in a series of experiments using rats as subjects. Habituation, defined as a decrease in ambulation, was greater on a second trial occurring 5 min after a first trial than on one occurring 60 min after. This short-term decrement occurred only when the same maze was used on both trials, and could be dishabituated by intertriai detention in another novel environment. On a delayed test trial, habituation was, in one case, somewhat greater following initial spaced trials, and in another condition, comparable following both massed and spaced trials. The longer term habituation was maze specific, but was not affected by the presence of a dishabituator following either or both of the first two trials. The results were discussed in terms of theories of “priming” and encoding variability.  相似文献   
157.
158.
A group of 633 college students at a large midwestern public university was asked fifteen questions pertaining to personal long-term course planning. The results indicated that only 48% of the students sketched out a tentative listing of at least two courses per term for one or more subsequent semesters when first planning courses for the current semester. Long-range planning was positively correlated with the number of years students had already spent in college and with students' perception of the following factors: course planning utility, degree of certainty about pursuing one's current first choice of career, and degree of commitment in using college coursework as a means of achieving a career goal (all p < 0.001). Long-range planning was negatively correlated with the anticipation of a possible change in academic interests. Such planning was not significantly correlated with students' entrance examination aptitude scores or grade point averages. Thus, students' long-range planning of courses was associated more strongly with career commitment than with recent academic performance or aptitude.  相似文献   
159.
Salary comparisons: New methods for correcting old fallacies   总被引:1,自引:0,他引:1  
Institutions of higher education place high priority on ensuring that their faculties are adequately paid. Since gauging the adequacy of compensation is a problem of relative measure, this assessment is usually performed by comparing university-level average salaries for a group of peer institutions. Often the potential distortions caused by differences in the rank mix of the faculty are forestalled by comparing average salaries for each of the four ranks. However, few if any institutions take similar steps to prevent the skewing of averages owing to differences in cost of living, differences in distribution of faculty in academic year and twelve-month appointments, and differences in the configuration of the faculty over disciplines. This paper shows that salary comparisons that do not compensate for these variation in staff mix are seriously flawed. A recommended methodology is demonstrated.  相似文献   
160.
A new approach for partitioning test items into dimensionally distinct item clusters is introduced. The core of the approach is a new item-pair conditional-covariance-based proximity measure that can be used with hierarchical cluster analysis. An extensive simulation study designed to test the limits of the approach indicates that when approximate simple structure holds, the procedure can correctly partition the test into dimensionally homogeneous item clusters even for very high correlations between the latent dimensions. In particular, the procedure can correctly classify (on average) over 90% of the items for correlations as high as .9. The cooperative role that the procedure can play when used in conjunction with other dimensionality assessment procedures is 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