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As the costs of certain types of scientific research have escalated and as growth rates in overall national science budgets have declined, so the need for an explicit science policy has grown more urgent. In order to establish priorities between research groups competing for scarce funds, one of the most important pieces of information needed by science policy-makers is an assessment of those groups' recent scientific performance. This paper suggests a method for evaluating that performance.After reviewing the literature on scientific assessment, we argue that, while there are no simple measures of the contributions to scientific knowledge made by scientists, there are a number of ‘partial indicators’ — that is, variables determined partly by the magnitude of the particular contributions, and partly by ‘other factors’. If the partial indicators are to yield reliable results, then the influence of these ‘other factors’ must be minimised. This is the aim of the method of ‘converging partial indicators’ proposed in this paper. We argue that the method overcomes many of the problems encountered in previous work on scientific assessment by incorporating the following elements: (1) the indicators are applied to research groups rather than individual scientists; (2) the indicators based on citations are seen as reflecting the impact, rather than the quality or importance, of the research work; (3) a range of indicators are employed, each of which focusses on different aspects of a group's performance; (4) the indicators are applied to matched groups, comparing ‘like’ with ‘like’ as far as possible; (5) because of the imperfect or partial nature of the indicators, only in those cases where they yield convergent results can it be assumed that the influence of the ‘other factors’ has been kept relatively small (i.e. the matching of the groups has been largely successful), and that the indicators therefore provide a reasonably reliable estimate of the contribution to scientific progress made by different research groups.In an empirical study of four radio astronomy observatories, the method of converging partial indicators is tested, and several of the indicators (publications per researcher, citations per paper, numbers of highly cited papers, and peer evaluation) are found to give fairly consistent results. The results are of relevance to two questions: (a) can basic research be assessed? (b) more specifically, can significant differences in the research performance of radio astronomy centres be identified? We would maintain that the evidence presented in this paper is sufficient to justify a positive answer to both these questions, and hence to show that the method of converging partial indicators can yield information useful to science policy-makers.  相似文献   
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Homocysteine(Hcy) has been implicated as a novel risk factor of Coronary Artery Disease (CAD) among Asian Indians, but many studies done in India failed to reveal any direct correlation. It has also been reported that Folic acid and Vitamin B12 levels inversely affect serum levels of homocysteine. In this study, we looked at the levels of homocysteine among patients with CAD. The effect of Vitamin B12, Folate and other risk factors on homocysteine levels were also evaluated. Mean homocysteine levels in cases (22.81±13.9, n=70) were significantly higher (p=<0.001) than the controls (7.77±7.3, n=70). However no statistically significant correlation could be deduced between homocysteine Vitamin B12, and Folate. Cumulative analysis have indicated an increase in homocysteine levels among patients with CAD with every additional risk factor.  相似文献   
164.
The innovative performance of companies has been studied quite extensively and for a long period of time. However, the results of many studies have not yet led to a generally accepted indicator of innovative performance or a common set of indicators. So far the variety in terms of constructs, measurements, samples, industries and countries has been substantial. This paper studies the innovative performance of a large international sample of nearly 1200 companies in four high-tech industries, using a variety of indicators. These indicators range from R&D inputs, patent counts and patent citations to new product announcements. The study establishes that a composite construct based on these four indicators clearly catches a latent variable ‘innovative performance’. However, our findings also suggest that the statistical overlap between these indicators is that strong that future research might also consider using any of these indicators to measure the innovative performance of companies in high-tech industries.  相似文献   
165.
We present a practical way of adapting and using four research-based assessments for different purposes in an electricity and magnetism course for K-8 science teachers. The course is designed to accomplish conceptual change toward accepted scientific conceptions as well as introducing teachers to materials and activities appropriate for their classrooms. Our data support that using the research-based tests to identify alternative conceptions and discuss test results with teachers is a promising way to use the knowledge of alternative conceptions in professional development. We also identify some mismatches between the research of conceptual change and its use in programs of professional development.
Ji ShenEmail:
  相似文献   
166.
怎样教科学   总被引:1,自引:0,他引:1  
科学教育的主要目的是为学生进行更高层次的科学学习奠定基础;有助于学生成为社会劳动力、寻求就业机会和谋求个人发展;为学生成为具有良好科学素养的社会公民奠定基础。为此,科学教学应坚持如下原则:教学应成为促进学生学习的工具;教学要专注于核心科学思想;教学要帮助学生加深对科学的理解;教学要充分考虑学习的复杂性;教学应有助于学生主动建构科学知识;教学应将科学内容和发展学生的兴趣相结合;教师要对所有学生的学习都寄予积极的期望;教学要注重减轻学生的焦虑。这八项教学原则及其教学实践建议,为改进科学教育提供了新的视角及可资借鉴的实践策略。  相似文献   
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One hundred thirty-eight fifth-grade students from three upstate New York school districts were administered a 1930s version of the Pintner General Ability Tests: Verbal Series. Scores from this test were compared and correlated with scores from current IQ and achievement tests. The Pintner means were similar to those of the current IQ tests; the correlations of the Pintner with the other tests were of the same order as those typically reported among contemporary measures; and item difficulty, as indicated by rank order, appeared similar for the current sample and the 1930s norm groups. The findings are discussed with reference to research that has shown sharp increases in IQs of Americans since the 1930s and questions concerning changes in mental ability measures.  相似文献   
170.
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