全文获取类型
收费全文 | 30882篇 |
免费 | 438篇 |
国内免费 | 20篇 |
专业分类
教育 | 21660篇 |
科学研究 | 2955篇 |
各国文化 | 544篇 |
体育 | 2458篇 |
综合类 | 15篇 |
文化理论 | 235篇 |
信息传播 | 3473篇 |
出版年
2022年 | 231篇 |
2021年 | 325篇 |
2020年 | 498篇 |
2019年 | 738篇 |
2018年 | 1013篇 |
2017年 | 1009篇 |
2016年 | 880篇 |
2015年 | 542篇 |
2014年 | 806篇 |
2013年 | 5858篇 |
2012年 | 787篇 |
2011年 | 808篇 |
2010年 | 613篇 |
2009年 | 627篇 |
2008年 | 729篇 |
2007年 | 665篇 |
2006年 | 589篇 |
2005年 | 552篇 |
2004年 | 532篇 |
2003年 | 464篇 |
2002年 | 448篇 |
2001年 | 585篇 |
2000年 | 540篇 |
1999年 | 475篇 |
1998年 | 274篇 |
1997年 | 283篇 |
1996年 | 295篇 |
1995年 | 296篇 |
1994年 | 238篇 |
1993年 | 275篇 |
1992年 | 435篇 |
1991年 | 419篇 |
1990年 | 425篇 |
1989年 | 431篇 |
1988年 | 356篇 |
1987年 | 395篇 |
1986年 | 359篇 |
1985年 | 440篇 |
1984年 | 348篇 |
1983年 | 315篇 |
1982年 | 275篇 |
1981年 | 237篇 |
1980年 | 239篇 |
1979年 | 370篇 |
1978年 | 262篇 |
1977年 | 241篇 |
1976年 | 221篇 |
1975年 | 203篇 |
1974年 | 222篇 |
1971年 | 198篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
John M. Budd 《Publishing Research Quarterly》1991,7(2):27-37
In recent years university presses have undergone some significant changes, such as expansion of their scope to include materials
that may have appeal beyond the scholarly market. This article investigates, through the use of a survey of university libraries,
the acquisition of university press products by libraries. In general, recent years have been changes in the relationship
between university presses and libraries that have resulted in fewer items being purchased by the libraries. 相似文献
12.
Donald D. Deshler Jean B. Schumaker B. Keith Lenz Janis A. Bulgren Michael F. Hock Jim Knight Barbara J. Ehren 《Learning disabilities research & practice》2001,16(2):96-108
Three factors tied with secondary student success in content‐area reading are demonstrated: (a) validated teacher‐focused and student‐focused interventions, (b) integrated and comprehensive service delivery systems, and (c) well‐designed, data‐based professional developmental programs. Difficult challenges face secondary students with LD and their teachers with regard to these students’ participation and success in required general education classes. Recently, instructional methods and materials have been developed and validated for promoting these students’ success. Some of them focus on how general education teachers plan and teach their content‐area courses; others focus on giving students the strategies they need to respond independently to the demands of their courses. This article describes these instructional methods, a service‐delivery model for implementing these interventions in secondary schools, and professional‐development mechanisms and administrative support that must be in place for the model to be maintained effectively. 相似文献
13.
14.
15.
16.
17.
18.
19.
20.
The purpose of this investigation was to describe the morphological parameters that characterize elite age group divers. Comparisons are made to normative age group data from the Coquitlam Growth Study and the constancy of important characteristics from age group to age group is examined. Data were collected on 27 male and 28 female elite divers who participated in the 1990 North American Age Group Diving Championships. Body build, body composition and skinfold corrected diameters were determined from 36 anthropometric parameters and analysed by ANOVA, t-test and Phantom z-scores procedures. All age groups except the 14- to 15-year-old males were significantly (P < or = 0.05) shorter than their norms but recorded higher androgyny index values. The estimated relative muscle mass increased significantly (P < or = 0.05) with age for males at all ages (40.8-46.3%). The 16- to 18-year-old females had a significantly (P < or = 0.05) larger relative muscle component compared to the younger age groups (40.1-38.4%). When normalized for height, active tissue development of the extremities was comparable between the sexes except in the forearm. The results indicate that at all age levels short stature is an important characteristic for divers. Analysis of regional active tissue development provides further insight into sport-specific prerequisites for success at elite levels. 相似文献