全文获取类型
| 收费全文 | 5317篇 |
| 免费 | 85篇 |
| 国内免费 | 20篇 |
专业分类
| 教育 | 3590篇 |
| 科学研究 | 642篇 |
| 各国文化 | 33篇 |
| 体育 | 474篇 |
| 综合类 | 6篇 |
| 文化理论 | 39篇 |
| 信息传播 | 638篇 |
出版年
| 2022年 | 39篇 |
| 2021年 | 53篇 |
| 2020年 | 100篇 |
| 2019年 | 151篇 |
| 2018年 | 192篇 |
| 2017年 | 220篇 |
| 2016年 | 178篇 |
| 2015年 | 134篇 |
| 2014年 | 177篇 |
| 2013年 | 906篇 |
| 2012年 | 148篇 |
| 2011年 | 149篇 |
| 2010年 | 125篇 |
| 2009年 | 108篇 |
| 2008年 | 120篇 |
| 2007年 | 137篇 |
| 2006年 | 109篇 |
| 2005年 | 76篇 |
| 2004年 | 91篇 |
| 2003年 | 83篇 |
| 2002年 | 65篇 |
| 2001年 | 105篇 |
| 2000年 | 131篇 |
| 1999年 | 92篇 |
| 1998年 | 72篇 |
| 1997年 | 64篇 |
| 1996年 | 62篇 |
| 1995年 | 46篇 |
| 1994年 | 47篇 |
| 1993年 | 35篇 |
| 1992年 | 77篇 |
| 1991年 | 69篇 |
| 1990年 | 61篇 |
| 1989年 | 63篇 |
| 1988年 | 74篇 |
| 1987年 | 58篇 |
| 1986年 | 78篇 |
| 1985年 | 71篇 |
| 1984年 | 55篇 |
| 1983年 | 69篇 |
| 1982年 | 55篇 |
| 1981年 | 41篇 |
| 1980年 | 29篇 |
| 1979年 | 52篇 |
| 1978年 | 50篇 |
| 1977年 | 37篇 |
| 1976年 | 41篇 |
| 1975年 | 32篇 |
| 1974年 | 30篇 |
| 1973年 | 33篇 |
排序方式： 共有5422条查询结果，搜索用时 453 毫秒
21.
Among the huge maze of resources available on the Internet, UnCoverWeb stands out as a valuable tool for medical libraries. This up-to-date, free-access, multidisciplinary database of periodical references is searched through an easy-to-learn graphical user interface that is a welcome improvement over the telnet version. This article reviews the basic and advanced search techniques for UnCoverWeb, as well as providing information on the document delivery functions and table of contents alerting service called Reveal. UnCover's currency is evaluated and compared with other current awareness resources. System deficiencies are discussed, with the conclusion that although UnCoverWeb lacks the sophisticated features of many commercial database search services, it is nonetheless a useful addition to the repertoire of information sources available in a library. 相似文献
22.
23.
24.
25.
26.
27.
28.
29.
Our library has previously investigated the potential impact the addition of contents notes on circulation. In a subsequent study, we found contents notes were the second metadata element most heavily linked to circulation (title was first). Since there has been a marked decline in the use of print resources at our library and a corresponding increase in digital resources, we wanted to know if the addition of contents notes to records for online streaming audio files would result in a similar increase in usage. After enhancing the records, we tracked usage for a period of three months. 相似文献
30.
Yu. N. Schuko 《Scientific and Technical Information Processing》2018,45(3):163-167
Although the USSR and the United States had a comparable number of employees in the field of scientific information, there was a substantial difference in funding, which resulted in a lack of information support for Soviet scientists. While 90% of the publications in the United States were available almost immediately after their release, in the USSR they were delayed by 1.5 to 2 years. Since the publication of the Abstracts Journal by VINITI (AJ), its content was consistently expanding and reached its peak in 1990 (1.5 million documents per year). The next quarter of a century was characterized by a decline in both the composition of the AJ and the time required for its document coverage. The steps for restructuring VINITI activities are discussed. The focus is made on improving the limited coverage of the Russian-language part of the global flow of scientific information by Western information systems. 相似文献