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161.
Within the UK, the "Long Term Athlete Development" (LTAD) model has been proposed by a variety of national governing bodies to offer a first step to considering the approach to talent development. The model, which is primarily a physiological perspective, presents an advancement of understanding of developing athletic potential alongside biological growth. It focuses on training to optimize performance longitudinally, and considers sensitive developmental periods known as "windows of opportunity". However, it appears that there are a number of problems with this theoretical model that are not necessarily transparent to coaches. Principally, the model is only one-dimensional, there is a lack of empirical evidence upon which the model is based, and interpretations of the model are restricted because the data on which it is based rely on questionable assumptions and erroneous methodologies. Fundamentally, this is a generic model rather than an individualized plan for athletes. It is crucial that the LTAD model is seen as a "work in progress" and the challenge, particularly for paediatric exercise scientists, is to question, test, and revise the model. It is unlikely that this can be accomplished using classical experimental research methodology but this should not deter practitioners from acquiring valid and reliable evidence.  相似文献   
162.
Evidence suggests the development of fundamental movement skill (FMS) is a key factor in promoting long-term physical activity. Low levels of activity among preschool children and the relationship between physical activity and the development of fundamental movement skills underline the need to determine the factors associated with children's development of such skills. As parents play an important role in the socialization process, the aim of this study was to examine correlates of family and neighbourhood characteristics as well as parental behaviour and beliefs on FMS performance in 4- to 6-year-old preschool children. Relationships between preschool children's FMS performance and family contextual variables were examined within a sample of 846 preschool children. Results identified positive associations of FMS performance with parental education, father's physical activity, transport to school by bicycle, and the high value placed by parents high on sport-specific aspects of children's physical activity. Variables negatively associated with preschool children's FMS performance included father-child interaction in TV-viewing and reading books, the high importance placed by parents on winning and performance in children's physical activity. Furthermore, the ambiguity of associations between FMS performance and parental beliefs underlined its complexity.  相似文献   
163.
Separation and sorting of biological entities (viruses, bacteria, and cells) is a critical step in any microfluidic lab-on-a-chip device. Acoustofluidics platforms have demonstrated their ability to use physical characteristics of cells to perform label-free separation. Bandpass-type sorting methods of medium-sized entities from a mixture have been presented using acoustic techniques; however, they require multiple transducers, lack support for various target populations, can be sensitive to flow variations, or have not been verified for continuous flow sorting of biological cells. To our knowledge, this paper presents the first acoustic bandpass method that overcomes all these limitations and presents an inherently reconfigurable technique with a single transducer pair for stable continuous flow sorting of blood cells. The sorting method is first demonstrated for polystyrene particles of sizes 6, 10, and 14.5 μm in diameter with measured purity and efficiency coefficients above 75 ± 6% and 85 ± 9%, respectively. The sorting strategy was further validated in the separation of red blood cells from white blood cells and 1 μm polystyrene particles with 78 ± 8% efficiency and 74 ± 6% purity, respectively, at a flow rate of at least 1 μl/min, enabling to process finger prick blood samples within minutes.  相似文献   
164.
International Journal of Science and Mathematics Education - The “leaky pipeline” with regard to students’ engagement in Science, Technology, Engineering, and Mathematics (STEM)...  相似文献   
165.
马德  马高强 《家教指南》2022,(1):137-142
120多年来,世界范围内敦煌研究取得了一定的成就,为今后的研究奠定了基础。在这个基础上,需要认识敦煌历史文化作为精神财富对人类社会进步发展的价值意义;需要转变传统观念,改进研究方法,开创新的研究局面,促进敦煌事业的发展,为新时代坚持中国特色社会主义建设提供精神支撑。  相似文献   
166.
This is part of a new series in this regular feature regarding trends in the provision of information by health science libraries. By sharing expertise and drawing together relevant trends the series intends to serve as a road map for both health science librarians and health informatics professionals. This article shows how a medical and biomedical research library changed practices, and reassessed user needs for the COVID‐19 emergency. Discusses changes to online education (and collaborative working) to provide user‐friendly services, researcher support tailored to need and re‐visioning library space. J.M.  相似文献   
167.
The tools used in learning processes are in a continuous state of flux. One of the most significant changes is the application of Information and Communications technologies (ICTs) to educational contexts. This provides new possible ways to carry out learning activities, new learning services, the possibility to use new kinds of contents and activities, etc. However, ICTs have not provided as many advantages as they were supposed to, so changes are necessary. In this context, a new set of tools, Web 2.0, offers a new way to understand the Web, in which the user is the centre. Further, users can cooperate in order to define contents. This concept is also applied in technology-mediated learning but there are important problems when one tries to integrate such tools and concepts with existing systems. This paper explores the integration of these tools in traditional learning environments, the various possibilities and their advantages and drawbacks. After that, an interoperability scenario is described and two experiences are presented to show how 2.0 tools can be integrated in learning activities, and its effect in educational process.  相似文献   
168.
Assessment is an important aspect of medical education because it tests students' competence and motivates them to study. Various assessment methods, with and without images, are used in the study of anatomy. In this study, we investigated the use of extended matching questions (EMQs). To gain insight into the influence of images on the validity of test items, we focused on students' cognitive processes while they answered questions with and without images. Seventeen first‐year medical students answered EMQs about gross anatomy, combined with either labeled images or answer lists, while thinking aloud. The participants' verbal reports were transcribed verbatim and then coded. Initial codes were based on a task analysis and were adapted into final codes during the coding process. Results showed that students used more cues from EMQs with images and visualized more often in EMQs with answer lists. Ready knowledge and verbal reasoning were used equally often in both conditions. In conclusion, EMQs with and without images elicit different results in this think aloud experiment, indicating different cognitive processes. They seem to measure different skills, making them valid for different testing purposes. The take‐home message for anatomy teachers is that questions without images seem to test the quality of students' mental images while questions with images test their ability to interpret visual information. It makes sense to use both response formats in tests. Using images from clinical practice instead of anatomical drawings will help to improve test validity. Anat Sci Educ 7: 107–116. © 2013 American Association of Anatomists.  相似文献   
169.
针对我国首个居民使用页岩气镇——宜宾市珙县上罗镇,通过走访、问卷调查、咨询专家及现场考察方式,主要从市场、需求、价格、影响因素等方面进行调查;分析并提出对页岩气开采应减少水资源污染、提供能源补贴,鼓励使用新型能源并积极推进页岩气民营化的进度.  相似文献   
170.
针对某电厂600MW对冲燃烧型锅炉运行出现的问题,理论分析结合试验调整,解决运行出现的问题。结果表明:减小磨煤机分离器挡板开度及燃尽风的旋流强度有助于煤粉在炉内的燃烬;合理的提高运行氧量,可以减少炉膛出口CO数值;调平一次风风速、减小炉内温度场偏差及降低炉膛出口烟气温度可以降低过热器、再热器管壁温度,有效解决管壁超温现象。  相似文献   
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