全文获取类型
收费全文 | 3719篇 |
免费 | 33篇 |
国内免费 | 2篇 |
专业分类
教育 | 2689篇 |
科学研究 | 364篇 |
各国文化 | 73篇 |
体育 | 189篇 |
综合类 | 2篇 |
文化理论 | 45篇 |
信息传播 | 392篇 |
出版年
2020年 | 28篇 |
2019年 | 44篇 |
2018年 | 71篇 |
2017年 | 68篇 |
2016年 | 79篇 |
2015年 | 43篇 |
2014年 | 52篇 |
2013年 | 978篇 |
2012年 | 46篇 |
2011年 | 56篇 |
2010年 | 46篇 |
2009年 | 64篇 |
2008年 | 60篇 |
2007年 | 50篇 |
2006年 | 65篇 |
2005年 | 42篇 |
2004年 | 50篇 |
2003年 | 43篇 |
2002年 | 45篇 |
2001年 | 49篇 |
2000年 | 58篇 |
1999年 | 43篇 |
1998年 | 53篇 |
1997年 | 46篇 |
1996年 | 50篇 |
1995年 | 55篇 |
1994年 | 56篇 |
1993年 | 53篇 |
1992年 | 65篇 |
1991年 | 56篇 |
1990年 | 46篇 |
1989年 | 45篇 |
1988年 | 49篇 |
1987年 | 50篇 |
1986年 | 47篇 |
1985年 | 59篇 |
1984年 | 42篇 |
1983年 | 40篇 |
1982年 | 61篇 |
1981年 | 35篇 |
1980年 | 49篇 |
1979年 | 48篇 |
1978年 | 34篇 |
1977年 | 29篇 |
1976年 | 38篇 |
1975年 | 38篇 |
1974年 | 26篇 |
1973年 | 24篇 |
1970年 | 23篇 |
1966年 | 20篇 |
排序方式: 共有3754条查询结果,搜索用时 15 毫秒
281.
282.
The ECDIN (Environmental Chemicals Data and Information Network) project started in 1973. During the pilot phase of operation the feasibility of the system was demonstrated using a data base of 4000 compounds and the SIMAS information retrieval system. It was quickly realised that for ECDIN data management was as important as information retrieval and in November 1977, after a study of available software, the ADABAS data base management system was installed at JRC Ispra for ECDIN and other JRC data banks. A design exercise for the ECDIN ADABAS data base has been completed and parts of the existing ECDIN data base have been converted to the new system. The problems encountered and the solutions adopted are discussed. The user interface to ECDIN is still under development. When fully operational ECDIN will be available through EURONET to both casual and specialist users and, in consequence, at least two levels of user interface will be required: (a) a user friendly conversational language designed for the casual user and capable of dealing with the more common types of question, (b) a sophisticated query language capable of answering the more difficult questions, producing “one-off” reports and probably requiring both a specialist knowledge of the data base and a programmer oriented background. The first tentative steps in this direction are described. 相似文献
283.
284.
285.
Selective attentional effects of textbook study questions on student learning in science 总被引:1,自引:0,他引:1
William G. Holliday 《科学教学研究杂志》1981,18(4):283-289
A selective attentional model used to explain recent mathemagenic and related research findings also predicted that textbook study questions adjunct to a flow diagram focus students' attention more upon questioned information and less upon nonquestioned information. Furthermore, the chances of such dysfunctional selective attention are increased when students are provided with a mere sampling (partial set) of study questions covering only portions of the diagram and are decreased when students are provided with a population (complete set) of questions or a no-question treatment. As predicted, using the Newman-Keuls procedure (p <0.05), the population and no-question treatment groups outperformed the sampling-question group which, in turn, outperformed a placebo-control group. It was concluded that researchers and teachers should be aware that encouraging students to concentrate on selective portions of critical information can result in inadequate processing of such specialized science materials as flow diagrams. 相似文献
286.
The results from use of behaviour therapy with child abuse cases is very encouraging. Data has been presented to show the approach both economical and rewarding. Our experience suggests that selected social workers may be able to learn to use the approach with a relatively short period of training. 相似文献
287.
288.
289.
290.