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   14997篇
  免费   215篇
  国内免费   13篇
教育   10263篇
科学研究   1321篇
各国文化   158篇
体育   1532篇
综合类   22篇
文化理论   105篇
信息传播   1824篇
  2021年   125篇
  2020年   234篇
  2019年   324篇
  2018年   391篇
  2017年   460篇
  2016年   396篇
  2015年   263篇
  2014年   348篇
  2013年   2676篇
  2012年   292篇
  2011年   335篇
  2010年   265篇
  2009年   287篇
  2008年   274篇
  2007年   266篇
  2006年   257篇
  2005年   227篇
  2004年   473篇
  2003年   364篇
  2002年   389篇
  2001年   254篇
  2000年   265篇
  1999年   204篇
  1998年   105篇
  1997年   125篇
  1996年   156篇
  1995年   141篇
  1994年   130篇
  1993年   130篇
  1992年   183篇
  1991年   183篇
  1990年   167篇
  1989年   218篇
  1988年   177篇
  1987年   209篇
  1986年   179篇
  1985年   235篇
  1984年   192篇
  1983年   176篇
  1982年   152篇
  1981年   132篇
  1980年   111篇
  1979年   174篇
  1978年   137篇
  1977年   122篇
  1976年   140篇
  1975年   103篇
  1974年   118篇
  1973年   97篇
  1971年   107篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
961.
962.
In this methodological discussion, the authors detail and reflect on the processes of using photo-elicitation interviewing as a way to align with positive qualitative methodologies, to gain access to participant beliefs and values, and to highlight participant voices through their choices of words and visuals. A review of the literature and an overview of the educational research experiences leading to the discussion are included. Next, the discoveries regarding what is methodologically new and/or valuable concerning this visual method is presented. In the final section, the authors reflexively contemplate aspects of visual methodological processes in an effort to address methodological crossroads of potential and tension including: (1) the potential of decontextualized photos, (2) photos as metaphors of meaning, (3) photos as representations of inherent meaning, (4) participant empowerment, and (5) graphic representation or graphic portraits.  相似文献   
963.
Published evaluations of career preparation of alumni from long-standing postdoctoral fellowship programs in the biomedical sciences are limited and often focus on quantitative analysis of data from extant publicly available sources. Qualitative methods provide the opportunity to gather robust information about specific program elements from structured postdoctoral training programs and the influence of this training on subsequent career paths of alumni. In-depth interviews with a subset of the National Cancer Institute’s Cancer Prevention Fellowship Program (CPFP) alumni (n = 27), representing more than 25 years of the program’s history and multiple career sectors, were conducted to assess alumni reflections on the training environment and career preparation during their time in the CPFP. NVivo software was used to analyze data and identify major themes. Four main themes emerged from these interviews, including: the value of structured training curriculum, mentorship, transdisciplinary environment, and professional identity. Even when reflecting on training that occurred one to two decades earlier, alumni were able to highlight specific components of a structured postdoctoral training program as influencing their research and career trajectories. These results may have relevance for those interested in assessing how postdoctoral training can influence fellows throughout their careers and understanding salient features of structured programs.  相似文献   
964.
The contributions of volunteers in special libraries have not been well-documented or researched. However, anecdotal evidence shows that volunteers have played a key role in the formation of many special libraries and continue to lend their skills and knowledge to these libraries. This column explores examples from the literature and gives a brief case study on the various ways philatelic libraries use volunteers. The scope of the column includes traditional unpaid volunteers, remote volunteers, crowdsourcing, internships, job training programs, and other voluntary or nontraditional work. Volunteer labor is far from free in terms of cost to the organization, but can provide benefits beyond simply unpaid labor including subject expertise, special skills, and community building. Special libraries looking to begin or expand volunteer programs are advised to study the lessons learned from other types of libraries and organizations with successful volunteer programs. Successfully managing volunteers requires careful planning and coordination just as managing paid staff does.  相似文献   
965.
The problem of the emergence and development of documentocentrism as a theoretical and methodological approach that views a document as a basic principle is discussed.  相似文献   
966.
Librarianship has a long tradition of collaboration and cooperation between libraries, but the literature yields scant evidence of formal partnerships in practice in special libraries. This column explores the barriers to collaboration for special libraries, from organizational culture to legal constraints, as well as the potential benefits and how librarians can overcome the barriers to reap these benefits. Different types of collaboration, including among similar special libraries and between special libraries and other types of libraries and related organizations, as well as informal and formal cooperation, and short-term and long-term partnerships, are discussed. Collaboration and cooperation were part of the impetus to form professional associations. The column provides a brief history of professional library associations and their role in supporting library partnerships in the United States. The conclusion explores how the increasingly digital nature of information and library work affects collaborative library efforts and where the future of these efforts may lie, especially for special libraries.  相似文献   
967.
Using Goffman's notions of self-presentation and gender displays, the following study examines the Instagram feeds of 27 professional athletes to determine how athletes are using the visual social media site for self-presentation. A mixed methods approach examined the photographs and captions to determine what behaviors and themes emerged. Through content analysis, the self-presentation styles of athletes of both genders, as well as the main differences between them were examined, and significant differences emerged that confirmed the previously established gender norms. Through textual analysis, findings with respect to captions align with previous research on athlete self-presentation on social media. Theoretical and practical implications, as well as directions for future research are discussed.  相似文献   
968.
Financial literacy, as a concept by that name, has only been explored in library science literature for a little over a decade. The concept, and especially the role of libraries in furthering this literacy, is still evolving. This systematic literature review examines the current definition of financial literacy, why financial literacy matters, where the public has been accessing financial literacy education to date, the difficulties encountered, by libraries and others, in providing this education, and how these challenges might be addressed moving forward.  相似文献   
969.
Three librarians who have extensive experience working in libraries or for publishers, vendors, or consortia presented an informal discussion on librarian–vendor relationships. The audience was encouraged to participate. Problems were articulated; speakers and audience members contributed suggestions for better approaches or behaviors when handling difficult situations.  相似文献   
970.
The flow focusing is a fundamental prior step in order to sort, analyze, and detect particles or cells. The standard hydrodynamic approach requires two fluids to be injected into the microfluidic device: one containing the sample and the other one, called the sheath fluid, allows squeezing the sample fluid into a narrow stream. The major drawback of this approach is the high complexity of the layout for microfluidic devices when parallel streams are required. In this work, we present a novel parallelized microfluidic device that enables hydrodynamic focusing in each microchannel using a single feed flow. At each of the parallel channels, a cross-filter region is present that allows removing fluid from the sample fluid. This fluid is used to create local sheath fluids that hydrodynamically pinch the sample fluid. The great advantage of the proposed device is that, since only one inlet is needed, multiple parallel micro-channels can be easily introduced into the design. In the paper, the design method is described and the numerical simulations performed to define the optimal design are summarized. Moreover, the operational functionality of devices tested by using both polystyrene beads and Acute Lymphoid Leukemia cells are shown.  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