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   8700篇
  免费   142篇
  国内免费   7篇
教育   6404篇
科学研究   503篇
各国文化   162篇
体育   739篇
综合类   3篇
文化理论   129篇
信息传播   909篇
  2022年   49篇
  2021年   77篇
  2020年   153篇
  2019年   221篇
  2018年   294篇
  2017年   320篇
  2016年   307篇
  2015年   229篇
  2014年   247篇
  2013年   1917篇
  2012年   235篇
  2011年   234篇
  2010年   217篇
  2009年   187篇
  2008年   285篇
  2007年   218篇
  2006年   221篇
  2005年   197篇
  2004年   156篇
  2003年   191篇
  2002年   174篇
  2001年   134篇
  2000年   123篇
  1999年   117篇
  1998年   110篇
  1997年   114篇
  1996年   124篇
  1995年   127篇
  1994年   119篇
  1993年   93篇
  1992年   112篇
  1991年   106篇
  1990年   102篇
  1989年   94篇
  1988年   86篇
  1987年   72篇
  1986年   67篇
  1985年   73篇
  1984年   62篇
  1983年   81篇
  1982年   76篇
  1981年   79篇
  1980年   84篇
  1979年   78篇
  1978年   55篇
  1977年   46篇
  1976年   52篇
  1975年   45篇
  1974年   41篇
  1971年   31篇
排序方式: 共有8849条查询结果,搜索用时 62 毫秒
31.
32.
Working Graphs     
  相似文献   
33.
An investigation has been undertaken at St Andrew’s church, Walpole St Andrew, Norfolk, to establish the underlying causes of the observed stone decay to the upper parts of the six stone piers. The stone decay was first recorded in the early 1930s. The salt-contaminated masonry within the church has been shown to undergo severe salt decay during the summer, with little damage occurring over the winter months. The south aisle piers have been shown to decay 2.5 times faster than the north aisle piers. Although crystallization–hydration cycles have been identified, the rate of decay is at its greatest when the cycling is relatively infrequent. This was not the expected trend. Furthermore, it has been shown that during extended periods where the ambient relative humidity is less than 75%, the rate of decay reaches a maximum. It is the length of this ‘drying’ period that apparently has the greatest influence on the rate of decay and could explain the significant difference in the rate of decay between the south and north aisle piers. The results have serious implications for passive conservation, where it is often recommended to lower the ambient relative humidity to well below the equilibrium relative humidity of the salt contaminant, to avoid crystallization–hydration cycles. Since, at the time of building, the church was situated on the coast, it is possible that the sodium chloride contamination occurred during the building process (1440–1520), particularly since the area was prone to sea-flooding at this time. Alternatively, the salt could have been applied as a treatment during the general restoration of 1897. Whatever the source of the salt, it seems likely that the ambient environment was changed by the insertion of a sealed floor in 1897, which could account for the onset of the salt decay.  相似文献   
34.
35.
彻底简化IT     
如何实现"简化IT"的战略,这是困扰很多企业,尤其是CIO的一个重要问题。本文以日本新生银行的例子来诠释如何彻底简化IT。中世纪哲人William of Ock- ham说过,理论应该尽可能的简单。同样的原则适用于企业IT系统:它们按照尽可能少的标准  相似文献   
36.
37.
38.
Book reviews     
Zwartjes, Otto, ed. La Sociedad andalusí y sus tradiciones literarias (Foro Hispánico, 7). Amsterdam: Rodopi, 1994.

Brincat, Joseph M. Malta 870–1054: Al‐Himyai's Account and its Linguistic Implications. Malta: Said International Ltd., 1995. 52pp.

Sells, Michael A. Mystical Languages of Unsaying. Chicago: The University of Chicago Press, 1994. 316 pp., US$18.95 (paperback), US$49.91 (cloth).

Diem, Werner, Arabische Geschäftsbriefe des 10. bis 14. Jahrhunderts aus der Österreichischen Nationalbibliothek in Wien (Documents Arabica Antiqua 1), 2 vols. Wiesbaden: Harrassowitz, 1995. Textband ix+518pp., Tafelband 76 plates.

Coope, Jessica A. The Martyrs of Cordoba: Community and Family Conflict in an Age of Mass Conversion. Lincoln: University of Nebraska Press, 1995. xvii+113 pp., US$ 25 (cloth).

Edwards, John. Religion and Society in Spain, c.1492 (Variorum Collected Studies Series: CS 520). Aldershot and Brookfield: Variorum, 1996. x+351 pp., US$ 97.00 (cloth).

Tolan, John Victor, ed. Medìeval Christian Perceptions of Islam. A Book of Essays (Garland Medieval Casebooks, Volume 10). New York and London: Garland Publishing, 1996. xxi+414 pp., US$60.00 (cloth).  相似文献   

39.
Indexing consistency in MEDLINE   总被引:3,自引:0,他引:3  
The quality of indexing of periodicals in a bibliographic data base cannot be measured directly, as there is no one "correct" way to index an item. However, consistency can be used to measure the reliability of indexing. To measure consistency in MEDLINE, 760 twice-indexed articles from 42 periodical issues were identified in the data base, and their indexing compared. Consistency, expressed as a percentage, was measured using Hooper's equation. Overall, checktags had the highest consistency. Medical Subject Headings (MeSH) and subheadings were applied more consistently to central concepts than to peripheral points. When subheadings were added to a main heading, consistency was lowered. "Floating" subheadings were more consistent than were attached subheadings. Indexing consistency was not affected by journal indexing priority, language, or length of the article. Terms from MeSH Tree Structure categories A, B, and D appeared more often than expected in the high-consistency articles; whereas terms from categories E, F, H, and N appeared more often than expected in the low-consistency articles. MEDLINE, with its excellent controlled vocabulary, exemplary quality control, and highly trained indexers, probably represents the state of the art in manually indexed data bases.  相似文献   
40.
This article first looks at the relationship between museums and art galleries and their potential audiences and, in particular, the under-represented sector of young visitors. It examines the main findings from the limited research available on young visitors, and goes on to discuss theories delineating the differences between the cultures, identities and values of culture consumers and culture providers. The second part of the article looks at what specific museums have done towards being more inclusive in their appeal, and then reports the findings of a survey of young people in relation to New Zealand's Auckland Art Gallery. The survey found that young people's ideas of what constitutes modern, relevant art do not match standard art criteria, and that most exhibitions and marketing methods do not mesh with their worldview. The article concludes by using data from the survey to suggest ways of engaging more young people with public art galleries.  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