全文获取类型
收费全文 | 19099篇 |
免费 | 195篇 |
国内免费 | 19篇 |
专业分类
教育 | 12594篇 |
科学研究 | 3119篇 |
各国文化 | 131篇 |
体育 | 1373篇 |
综合类 | 7篇 |
文化理论 | 134篇 |
信息传播 | 1955篇 |
出版年
2021年 | 198篇 |
2020年 | 285篇 |
2019年 | 406篇 |
2018年 | 600篇 |
2017年 | 558篇 |
2016年 | 491篇 |
2015年 | 316篇 |
2014年 | 497篇 |
2013年 | 3406篇 |
2012年 | 423篇 |
2011年 | 438篇 |
2010年 | 388篇 |
2009年 | 349篇 |
2008年 | 395篇 |
2007年 | 363篇 |
2006年 | 315篇 |
2005年 | 296篇 |
2004年 | 310篇 |
2003年 | 253篇 |
2002年 | 253篇 |
2001年 | 348篇 |
2000年 | 369篇 |
1999年 | 325篇 |
1998年 | 175篇 |
1997年 | 202篇 |
1996年 | 197篇 |
1995年 | 139篇 |
1994年 | 172篇 |
1993年 | 146篇 |
1992年 | 254篇 |
1991年 | 238篇 |
1990年 | 231篇 |
1989年 | 280篇 |
1988年 | 222篇 |
1987年 | 189篇 |
1986年 | 244篇 |
1985年 | 236篇 |
1984年 | 194篇 |
1983年 | 199篇 |
1982年 | 156篇 |
1981年 | 140篇 |
1980年 | 136篇 |
1979年 | 213篇 |
1978年 | 153篇 |
1977年 | 150篇 |
1976年 | 134篇 |
1975年 | 113篇 |
1974年 | 141篇 |
1973年 | 124篇 |
1971年 | 125篇 |
排序方式: 共有10000条查询结果,搜索用时 784 毫秒
101.
Maxfield DK 《Bulletin of the Medical Library Association》1975,63(3):345-346
102.
103.
A brief commentary from the Museum Association of New York (MANY) on the unprecedented gap posed by baby-boomer retirement. Based, in part, on MANY's white paper, “Who's Next? Questioning the Future of Museum Leadership in New York State,” this essay deals with questions of succession, leadership and general differences in New York's museum community. 相似文献
104.
Karyn Ogata Jones Bryan E. Denham Jeffrey K. Springston 《Journal of Applied Communication Research》2006,34(1):94-113
Drawing on components of agenda-setting theory and the two-step flow of information from mass media to news audiences, this study examines the effects of mass and interpersonal communication on breast cancer screening practices among college- and middle-aged women (n = 284). We theorized that screening behaviors among younger women would be influenced more by interpersonal sources of information while screening among middle-aged women would be more influenced by exposure to mass-mediated information. Findings supported anticipated patterns, revealing important and varying roles for both mass and interpersonal communication in the health behaviors of women. Implications for health practitioners and campaign planners, as well as recommendations for future research, are discussed. 相似文献
105.
Tuomo Korenius Jorma Laurikkala Martti Juhola Kalervo Järvelin 《Information Retrieval》2006,9(1):33-53
Search facilitated with agglomerative hierarchical clustering methods was studied in a collection of Finnish newspaper articles
(N = 53,893). To allow quick experiments, clustering was applied to a sample (N = 5,000) that was reduced with principal components analysis. The dendrograms were heuristically cut to find an optimal partition,
whose clusters were compared with each of the 30 queries to retrieve the best-matching cluster. The four-level relevance assessment
was collapsed into a binary one by (A) considering all the relevant and (B) only the highly relevant documents relevant, respectively.
Single linkage (SL) was the worst method. It created many tiny clusters, and, consequently, searches enabled with it had high
precision and low recall. The complete linkage (CL), average linkage (AL), and Ward's methods (WM) returned reasonably-sized
clusters typically of 18–32 documents. Their recall (A: 27–52%, B: 50–82%) and precision (A: 83–90%, B: 18–21%) was higher
than and comparable to those of the SL clusters, respectively. The AL and WM clustering had 1–8% better effectiveness than
nearest neighbor searching (NN), and SL and CL were 1–9% less efficient that NN. However, the differences were statistically
insignificant. When evaluated with the liberal assessment A, the results suggest that the AL and WM clustering offer better
retrieval ability than NN. Assessment B renders the AL and WM clustering better than NN, when recall is considered more important
than precision. The results imply that collections in the highly inflectional and agglutinative languages, such as Finnish,
may be clustered as the collections in English, provided that documents are appropriately preprocessed. 相似文献
106.
This study examined two levels of media agenda effects on aggregatepublic opinion from different news sources. The effects wereinvestigated immediately and cumulatively. Content analysisdata from the 2000 U.S. presidential election coverage by fournational news organizations were related to the Gallup pre-electionpoll standings of each candidate. Regression analyses foundthat both the salience of a candidate and the salience of theattributes of a candidate cumulatively, but not immediately,influenced his standing in the polls. An analysis of news sourcessupported the finding that the two levels of agenda-settingeffects seemed mostly cumulative rather than immediate. Newsfrom different sources, however, tended to have effects of differentdegrees and sometimes different directions on candidate pollstandings. Cumulative effects of candidate salience on aggregateopinion change were found for non-partisan and neutral newssourcesreporters, poll reporting and public documentswhereasthe effects of candidate attribute salience mostly came frompartisan sourcesthe candidate himself and members ofthe competing political party. Possible political implicationsof these findings are discussed. 相似文献
107.
Bast fibres have been commonly used as a textile material in Northern Europe since Neolithic times. However, the process of identifying the different species has been problematic, and many important questions related to their cultural history are still unanswered. For example, a modified Herzog test and the presence of calcium oxalate crystals have both been used in identification. In order to generate more reliable results, further research and advancement in multi-methodological methods is required. This paper introduces a combination of methods which can be used to identify and distinguish flax (Linum usitatissimum), hemp (Cannabis sativa), and stinging nettle (Urtica dioica). The research material consisted of reference fibres and 25 fibre samples obtained from 12 textiles assumed to be made of nettle. The textiles were from the Finno-Ugric and Historical Collections of The National Museum of Finland. The fibre samples were studied by observing the surface characteristics and cross sections with transmitted light microscopy, and by using a modified Herzog test with polarized light, in order to identify the distinguishable features in their morphological structures. The study showed that five out of 25 samples were cotton, 16 nettle, one flax, and one hemp. Findings from two samples were inconsistent. The results show that it is possible to distinguish common north European bast fibres from each other by using a combination of microscopic methods. Furthermore, by utilizing these combined methods, new and more reliable information could be obtained from historical ethnographic textiles, which creates new vistas for the interpretation of their cultural history. 相似文献
108.
Steve H. Ching 《The Journal of Academic Librarianship》2018,44(2):196-206
The digital shift has provided easy access to academic library users, and yet, the usage of archival collections continues to be low. At the same time, the need for innovation in library services for cultural heritage scholarship and its advancement is emerging. This paper outlines a library-led service-learning program that connects students with lighthouse artifacts, archival collections, scholars in global academia, and wider communities. Student engagement cases are provided to illustrate the way in which the librarian utilizes the Framework of Information Literacy for Higher Education by ACRL to work closely with students. These cases also demonstrate how students can contribute to knowledge creation and preservation efforts for a specific cultural heritage topic that is not static, but which keeps receiving new contributions or additions to the depository. Thus, this paper is an answer to the ACRL's call for pilot projects to be assessed and shared with the wider community of academic librarians and support staff. It also builds on emerging roles for academic libraries like engaged learning. Librarians must move beyond simply seeing themselves as partners. Instead, librarians should see themselves as prime facilitators that co-create and co-develop cultural heritage research and historical projects by connecting actors and resources more effectively than any single actor can do alone. 相似文献
109.
Leanne K. Knobloch Erin D. Basinger Jennifer A. Theiss 《Journal of Applied Communication Research》2018,46(1):52-73
The transition from deployment to reintegration can be stressful for returning military personnel and at-home partners, and support plays a key role in their ability to transition effectively. We draw on relational turbulence theory to advance predictions about how parameters of the relationship between returning service members and at-home partners predict their perceptions of their partner’s support during the post-deployment transition. We surveyed 235 individuals (117 returning service members, 118 at-home partners) who had experienced the transition within the past 6 months. Findings consistent with the theory indicated that relational turbulence partially mediated the negative associations that relational uncertainty and interference from a partner shared with partner support. Partner uncertainty was a direct negative predictor of partner support as well. We consider how these results extend theory, research, and practice. 相似文献
110.
This article explores how the library-student liaison program at Eastern Washington University (EWU) Libraries has evolved into an opportunity for students to develop leadership skills. Originally designed to foster better communication between the EWU Libraries and students enrolled at the university, we recognized that the process of achieving established goals for the program provided a vehicle for students' leadership-skill development. To facilitate the leadership process, librarians employed the Social Change Model. Designed specifically for college students, this model engages the student to develop individual capacities to strengthen group activities that foster positive changes in the community and society. 相似文献