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961.
研究目的:假腮的功能早已引起科学家兴趣,但还有待阐明。本文通过研究硬骨鱼类品种虹鳟鱼(Oncorhynchus mykiss)的假腮碳酸酐酶的免疫定位,来探讨假腮碳酸酐酶的生理功能。研究方法:免疫组织化学染色技术。重要结论:免疫组化结果显示碳酸酐酶分布在假腮细胞中,更精确地说是在其细胞顶端分布。细胞基底端、管状系统、毛细血管和柱细胞均无免疫染色。免疫细胞化学定位进一步验证了这些结果,并显示一部分是细胞质碳酸酐酶,其余的与细胞膜结构连接。此外,腔隙层未显示出免疫过氧化物酶的活性。本研究揭示了假腮碳酸酐酶的功能与细胞外介质有关,碳酸酐酶能干预传入神经纤维刺激机制。  相似文献   
962.
Schools are an important context for both basic and applied scientific research. Unlike the laboratory, however, the physical and social conditions of schools are not under the exclusive control of scientists. In this article, we liken collecting data in schools to putting on a theatrical production. We begin by describing the large cast of characters whose collaborative efforts make school‐based research possible. Next, we address the critics, including the university Institutional Review Board (IRB) and school administrators, whose feedback often improves the final study design. We then turn our attention to set building, stage directions, and rehearsals—key steps in the iterative process of refining study procedures. We end with a discussion of the day of data collection itself and activities that take place after the curtain drops. Throughout, we make recommendations based on our recent experience collecting data at several high schools.  相似文献   
963.
Videos can be used as didactic tools for self‐learning under several circumstances, including those cases in which students are responsible for the development of this resource as an audiovisual notebook. We compared students' and teachers' perceptions regarding the main features that an audiovisual notebook should include. Four questionnaires with items about information, images, text and music, and filmmaking were used to investigate students' (n = 115) and teachers' perceptions (n = 28) regarding the development of a video focused on a histological technique. The results show that both students and teachers significantly prioritize informative components, images and filmmaking more than text and music. The scores were significantly higher for teachers than for students for all four components analyzed. The highest scores were given to items related to practical and medically oriented elements, and the lowest values were given to theoretical and complementary elements. For most items, there were no differences between genders. A strong positive correlation was found between the scores given to each item by teachers and students. These results show that both students' and teachers' perceptions tend to coincide for most items, and suggest that audiovisual notebooks developed by students would emphasize the same items as those perceived by teachers to be the most relevant. Further, these findings suggest that the use of video as an audiovisual learning notebook would not only preserve the curricular objectives but would also offer the advantages of self‐learning processes. Anat Sci Educ 7: 209–218. © 2013 American Association of Anatomists.  相似文献   
964.
Hands‐on educational experiences can stimulate student interest, increase knowledge retention, and enhance development of clinical skills. The Lachman test, used to assess the integrity of the anterior cruciate ligament (ACL), is commonly performed by health care professionals and is relatively easy to teach to first‐year health profession students. This study integrated teaching the Lachman test into a first‐year anatomy laboratory and examined if students receiving the training would be more confident, competent, and if the training would enhance anatomical learning. First‐year medical, physician assistant and physical therapy students were randomly assigned into either the intervention (Group A) or control group (Group B). Both groups received the course lecture on knee anatomy and training on how to perform the Lachman test during a surface anatomy class. Group A received an additional 15 minutes hands‐on training for the Lachman test utilizing a lightly embalmed cadaver as a simulated patient. One week later, both groups performed the Lachman test on a lightly embalmed cadaver and later completed a post‐test and survey. Students with hands‐on training performed significantly better than students with lecture‐only training in completing the checklist, a post‐test, and correctly diagnosing an ACL tear. Students in Group A also reported being more confident after hands‐on training compared to students receiving lecture‐only training. Both groups reported that incorporating clinical skill activities facilitated learning and created excitement for learning. Hands‐on training using lightly embalmed cadavers as patient simulators increased confidence and competence in performing the Lachman test and aided in learning anatomy. Anat Sci Educ 7: 181–190. © 2013 American Association of Anatomists.  相似文献   
965.
966.
It is becoming increasingly vital to publish and share research as well as get citations for the purpose of researcher visibility. The publishing options available for research distribution seem endless. It really is an academic jungle out there! This article reviews why early career researchers and graduate scholars should consider their research impact in the digital age.  相似文献   
967.
968.
The main aspects related to the development of a system for the aggregation and use of scientific results (hereinafter, the System) are discussed. A unified comprehensive approach to the development of the System and the qualitative improvement of the information about the performance of the Russian research sector provided to the target audience is being suggested for use by academic institutions, government regulators, and the business community. The improvement is meant to be achieved through the development of technology that provides access to the relevant electronic resources. The presented conclusions lay the basis for a range of research and development works in the field related to the collection of scientific results.  相似文献   
969.
970.
Three groups of social bookmarking users, namely experienced users, users with moderate level of experience, and novice users, were investigated, in terms of their reported tagging behaviors, perceived usefulness of social bookmarking in information discovery and management, and perceived usefulness of the bookmarking features provided. Based on the empirical analysis of the Connotea users, who are primarily in academia, the study shows that experienced academic users generally prefer to use social bookmarking while moderately experienced and novice users still prefer to use the traditional bookmarking methods, such as creating and using bookmarks on a dedicated computer. Experienced academic users were also found to create more tags per bookmark comparing to the other two groups. Most novice academic users, however, only created one tag per bookmark, which just met Connotea's minimum requirement. Surprisingly different from the collaborative design nature of the social bookmarking systems, the study finds that our participants, particularly experienced academic users, prefer to create and use their own bookmarks rather than sharing bookmarks created by others. In fact, experienced users have significantly higher frequency (once every two weeks) of creating bookmarks than the other two groups (once a month or less). In addition, website design features and functions, such as automatic collection of bibliographic information, are regarded by all participants as helpful for information discovery. The in-depth examination and discussion of the opinions of Connotea users may be useful for further improvement of the design features and usage applications, particularly for academic social bookmarking websites. The results may also have potential implications to the future development of social bookmarking services in general.  相似文献   
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