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941.
In two experiments using a radial-arm maze, pairs of rats made choices among eight maze locations, each containing a large quantity of one of two food types. The choices made by 1 rat affected the choices made by the other rat. Under most conditions, visits by 1 rat increased the tendency of the other rat to subsequently choose that maze location. However, the effect depended on the quality of the food available in a particular location. When it was possible for the rats to observe each other on the maze arms and a rat had experienced that a location contained the less preferred food type, a previous visit to that location by the foraging partner decreased the tendency to visit that location. These effects are attributed to working memory for the spatial choices of another rat, and they indicate that memory produced by a rat’s own visit to a maze location is integrated with memory for the behavior of another rat to determine spatial choice  相似文献   
942.
There are many influences on how assessors grade themselves and others. Oral presentations are useful for exploring such factors in peer, self‐ and tutor marked assessments, being rapidly completed and assessed, commonly used in HE and very difficult to anonymize. This opportunistic study examined the effects of gender and level of attainment on the triangulation of marks awarded to student presenters. Grades generated by peer assessment were associated more strongly with tutor‐awarded marks than those from self‐assessment. For self‐assessment there was a strong effect of gender (female students undervalued their performance compared with tutor grades). Peer assessment produced higher marks than from tutors, perhaps because of the close‐knit community developed during residential courses. For tutor marks, the greatest variability was at the lower end of the scale, whereas peer assessors were most variable when marking students who self‐evaluated or peer assessed highly. Students awarded a narrower range of marks to peers compared with tutors, but when self‐assessing used a larger range. Presentations by students who admitted to little sleep the night before received lower grades from both peers and tutors, but this was not reflected by self‐assessments, suggesting they were unaware of their poorer performances. Sessions with fewer talks (four rather than seven) reduced the ‘dip’ in marks previously observed in the middle of sessions. Findings are discussed in the context of bias in this mode of assessment.  相似文献   
943.
Research has shown that educational games can have positive impacts on student learning and motivation. The success of a game played in a library instruction class depends on the type of game selected, the development of learning outcomes, and the flexibility of the librarian during class. This article explains the benefits to students and librarians of using games, discusses the development and use of a Jeopardy-style game, and provides practical tips for librarians interested in developing and incorporating games into one-time library instruction sessions.  相似文献   
944.
The rigours of the past few years have demonstrated the importance of good health literacy levels with the imperative of being able to obtain and interpret information to maintain and improve one's health never more apparent. With this in mind, this issue is focused on consumer health information, the gender and population group differences that exist in information seeking behaviour, the challenges of understanding medical explanations and terminology, and existing criteria to assess and ultimately produce better consumer health information.  相似文献   
945.
Identifying and accessing reliable, relevant consumer health information rapidly on the Internet may challenge the health sciences librarian and layperson alike. In this study, seven search engines are compared using representative consumer health topics for their content relevancy, system features, and attributes. The paper discusses evaluation criteria; systematically compares relevant results; analyzes performance in terms of the strengths and weaknesses of the search engines; and illustrates effective search engine selection, search formulation, and strategies.  相似文献   
946.
Automatic detection of source code plagiarism is an important research field for both the commercial software industry and within the research community. Existing methods of plagiarism detection primarily involve exhaustive pairwise document comparison, which does not scale well for large software collections. To achieve scalability, we approach the problem from an information retrieval (IR) perspective. We retrieve a ranked list of candidate documents in response to a pseudo-query representation constructed from each source code document in the collection. The challenge in source code document retrieval is that the standard bag-of-words (BoW) representation model for such documents is likely to result in many false positives being retrieved, because of the use of identical programming language specific constructs and keywords. To address this problem, we make use of an abstract syntax tree (AST) representation of the source code documents. While the IR approach is efficient, it is essentially unsupervised in nature. To further improve its effectiveness, we apply a supervised classifier (pre-trained with features extracted from sample plagiarized source code pairs) on the top ranked retrieved documents. We report experiments on the SOCO-2014 dataset comprising 12K Java source files with almost 1M lines of code. Our experiments confirm that the AST based approach produces significantly better retrieval effectiveness than a standard BoW representation, i.e., the AST based approach is able to identify a higher number of plagiarized source code documents at top ranks in response to a query source code document. The supervised classifier, trained on features extracted from sample plagiarized source code pairs, is shown to effectively filter and thus further improve the ranked list of retrieved candidate plagiarized documents.  相似文献   
947.
In this article, I compare the assumptions, concepts, and propositions of media system dependency (MSD) theory and uses and gratifications (U&G) theory at the microlevel of analysis. The epistemological origins of these theories are situated within the differing social and personal contexts that affected their development. Those MSD assumptions that serve as background to this comparison are specified, and major hypotheses concerning the social ecology of microeffects processes are discussed, particularly as they pertain to public opinion concerns. Following this elaboration of MSD theory, basic differences between MSD and U&G conceptions of the audience, interpersonal networks, the media system, and the nature of media power are addressed. I conclude with a brief comment on the implications of the Internet for theorizing micro media effects.  相似文献   
948.
949.
A new compliance-gaining technique is introduced called the “just-one-more” (JOM) technique that increases compliance rates by including the phrase “I just need one more person to help.” Two studies are reported (N = 160 in each). The first established the effectiveness of the technique as compared to a direct request. The second tested the hypothesis that goal difficulty moderates the technique's effectiveness in a 2 (JOM or direct request) × 2 (requester needs five surveys or 100). Results indicate that the JOM was substantially more effective than a direct request in the 100 surveys condition but not the five.  相似文献   
950.
Effective delivery of biomedical information to health professionals depends on the availability of systems that are compatible with the information-seeking patterns of health professionals. MEDLINE is a major source of biomedical information, but has been available primarily through libraries via telecommunications networks. The recent availability of MEDLINE on CD-ROM has made it possible to provide MEDLINE directly to clinicians without the associated problems of telecommunications and online use charges. The MEDLINE on CD-ROM Evaluation Forum sponsored by the National Library of Medicine reported on clinicians' use of CD-ROM MEDLINE at seven different clinical settings. This article summarizes the findings from these sites and places them in the context of current understanding of information-seeking behaviors of health professionals. Key issues in the design and development of information technologies in the clinical setting are also articulated.  相似文献   
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