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991.
This article describes a study in which measures of mathematical knowledge for teaching developed in the United States were adapted to measure mathematical knowledge for teaching in Ireland. When adapting the measures it was not assumed that the mathematical knowledge used by Irish and U.S. teachers is the same. Instead psychometric and interview-based methods were used to determine a correspondence between the constructs being measured, and ensure the integrity of item performance in the Irish context. The study found overlap between the knowledge that is used to teach in both Ireland and the United States, and that the items tapped into this knowledge. However, specific findings confirm the usefulness of conducting extensive checks on the validity of items used in cross-national contexts. The process of adaptation is described to provide guidance for others interested in using the items to measure mathematical knowledge for teaching outside the United States. The process also enabled the authors to raise questions about the assumptions that lie behind the practice-based construct of mathematical knowledge for teaching.
Seán DelaneyEmail:
  相似文献   
992.
Students' conceptions are characterized by some authors as having a high degree of coherence while, in the minds of others, they show little coherence and great heterogeneity. The objective of this study was to throw light on this problem by reference to the particulate nature of matter, a topic where great discrepancies have been observed in the degree of coherence shown by students. We interviewed 43 students aged 9–22 years to evaluate the coherence of their replies, using a questionnaire in which different methodological strategies are incorporated, as will be explained below. A qualitative analysis of the students' replies to the interviewer's questions permitted a group of empirical categories to be established, which were then arranged hierarchically. The quantitative analysis of these categories gave rise to new categories, which we call structural categories. These permitted us to select the most significant variables, to identify the different types of conceptions held by the subjects and to assign to each a given level of conceptualization. They also revealed the high degree of coherence in the replies given to different tasks. The usefulness of the proposed method for studying students' conceptions and for evaluating their degree of coherence is confirmed. © 2006 Wiley Periodicals, Inc. J Res Sci Teach 43: 577–598, 2006  相似文献   
993.
Reading and discussing texts as a means for learning subject content are regular features within educational contexts. This paper presents an approach for intertextual content analysis (ICA) of such text-related discussions revealing what the participants make of the text. Thus, in contrast to many other approaches for analysing conversation that focus essentially on the interaction per se, ICA takes the text as its starting point. Drawing on the concept of text movability and systemic-functional cohesion analyses, the approach combines a reader’s perspective and a text perspective to show the participants’ reception of the text, and also what and how text content is brought into the conversation and how it is handled. In the paper, ICA is described with regard to its theoretical underpinnings, usage and utility. It is suggested that the approach provides educational researchers with an analytical tool that allows detailed ICAs of text-related classroom discussion. Findings may ultimately lead to pedagogical implications with a bearing on classroom practice.  相似文献   
994.
One hundred Anglo university students were asked to rate a number of ethnic/national groups (American, Chicano, Mexican American, Hispanic, Puerto Rican, Japanese, and German) on a Semantic Differential and to openly produce traits they identified with each group. As expected, the freely produced traits differed from those obtained in another study which used the Katz and Braly technique with students from the same university. Furthermore, differential evaluations were found for Chicanos and Mexican Americans in which the latter group was perceived more positively in the Evaluative Dimension, but not in terms of Potency or Activity. Also, as expected, having a member of the group as a friend produced the highest correlations with a positive perception of the group as a whole.  相似文献   
995.
Free radical production increases during exercise and oxidative damage occurs in several tissues. We examined the effects of three different exercise tests on the pattern of change of erythrocyte enzyme antioxidant activities. The tests were a short maximal exercise test, a submaximal prolonged exercise test and a cycling stage during competition. The participants were amateur and professional cyclists with different training statuses and different basal erythrocyte antioxidant enzyme activities. The maximal test produced no changes in the erythrocyte antioxidant enzyme activities of amateur sportsmen. The submaximal test, performed at 80% of maximal oxygen uptake, decreased erythrocyte catalase (12%), glutathione peroxidase determined with H2O2 (14%) and glutathione reductase (16%); superoxide dismutase activity increased by about 25%. The cycling stage performed by professional cyclists increased erythrocyte catalase (29%) and glutathione reductase (10%) activities. The in vivo changes in glutathione reductase activity were confirmed by in vitro measurements: hydrogen peroxide decreased and the presence of catalase increased the activity of this enzyme. In conclusion, we suggest that the different erythrocyte antioxidant enzyme responses to diverse exercise tests can be explained by the effects of hydrogen peroxide and the superoxide anion on the antioxidant enzyme activities in erythrocytes.  相似文献   
996.
The purpose of this study was to provide a more detailed analysis of performance in cross-country skiing by combining findings from a differential global positioning system (dGPS), metabolic gas measurements, speed in different sections of a ski-course and treadmill threshold data. Ten male skiers participated in a freestyle skiing field test (5.6 km), which was performed with dGPS and metabolic gas measurements. A treadmill running threshold test was also performed and the following parameters were derived: anaerobic threshold, threshold of decompensated metabolic acidosis, respiratory exchange ratio = 1, onset of blood lactate accumulation and peak oxygen uptake (VO2peak). The combined dGPS and metabolic gas measurements made detailed analysis of performance possible. The strongest correlations between the treadmill data and final skiing field test time were for VO2peak (l x min(-1)), respiratory exchange ratio = 1 (l x min(-1)) and onset of blood lactate accumulation (l x min(-1)) (r = -0.644 to - 0.750). However, all treadmill test data displayed stronger associations with speed in different stretches of the course than with final time, which stresses the value of a detailed analysis of performance in cross-country skiing. Mean oxygen uptake (VO2) in a particular stretch in relation to speed in the same stretch displayed its strongest correlation coefficients in most stretches when VO2 was presented in units litres per minute, rather than when VO2 was normalized to body mass (ml x kg(-1) x min(-1) and ml x min(-1) x kg(-2/3)). This suggests that heavy cross-country skiers have an advantage over their lighter counterparts. In one steep uphill stretch, however, VO2 (ml x min(-1) x kg(-2/3)) displayed the strongest association with speed, suggesting that in steep uphill sections light skiers could have an advantage over heavier skiers.  相似文献   
997.
Experimental high-energy and nuclear physics was created in Spain thanks to Joaquín Catalá de Alemany, who founded the Institute of Corpuscular Physics (IFIC) at the University of Valencia in 1950. The physics of photographic emulsions, cheap and easy to manipulate, were well adapted to the depressed situation in Spain following the Civil War. This essay describes how, using these techniques, Catalá de Alemany created a group, established links with international laboratories, and fostered a tradition that continues today.  相似文献   
998.
999.
Media presentations that attempt to improve intergroup relations often portray stigmatized group members in a sympathetic light in order to induce empathy. Emotion priming research suggests that induced empathy may not only affect reactions to those portrayed, but also to a wide range of secondary others. In order to test this possible secondary or transfer effect, the present study assessed whether empathy induced by a video of a boy with cancer could also increase caring for an unrelated stigmatized group member. Although the video was not found to have a direct effect, it did have a significant indirect effect on caring for the stigmatized group member, mediated by concern for the boy. In addition, this indirect effect was also moderated by both age and gender.  相似文献   
1000.
This study aimed to gather the opinions of editors of Library and Information Science journals indexed in Scopus and the Web of Knowledge regarding the current situation and their forecasts on open access, peer review procedures, functionalities, and specialization. The response rate was 23%, and some noteworthy conclusions can be drawn according to editors' opinions: Within 5–10 years, the main business model for journal publishing will be open access. Institutional support is the preferred source of financing. The review process requires less than 2 months, and the main problems are low quality of texts and finding reviewers. Functionalities such as mobile versions of the journals, social media, data policy, and altmetrics have yet to be exploited; interdisciplinarity will increase the presence of these functionalities in journals, especially through the influence of the related areas of Communication, Management, and Computer Science. Finally, the area that will see the most changes is the management of research data.  相似文献   
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