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71.
Book Reviews     
Serial Publications: Guidelines for Good Practice in Publishing Printed and Electronic Journals, 2nd edition, by Diane Brown, Elaine Stott and Anthony Watkinson Association of Learned and Professional Society Publishers 2003, £27 (members), £30 (non‐members), 108 pp., paperback. ISBN 0‐907341‐22‐5. Available from http://www.alpsp.org/pub3.htm The Case for Institutional Repositories: A SPARC Position Paper prepared by Raym Crow, SPARC Senior Consultant Scholarly Publishing and Academic Resources Coalition, Washington DC. Release 1.0, 2002. Available at: www.arl.org/sparc The Case for Institutional Repositories: A SPARC Position Paper prepared by Raym Crow, SPARC Senior Consultant Scholarly Publishing and Academic Resources Coalition, Washington, DC. Release 1.0, 2002. Available at: www.arl.org/sparc Internet Law: Text and Materials by Chris Reed Butterworths Tolley, 2000, £24.95, paperback. ISBN 0406981418 Intellectual Property Law by Lionel Bently and Brad Sherman Oxford University Press, Oxford, 2001, £32.99 (paperback), 1136 pp. ISBN 0‐19‐876343‐3 Clearing the Way: Copyright Clearance in UK Libraries by Elizabeth Gadd LISU Occasional Paper no. 31, Library & Information Statistics Unit (LISU), Department of Information Science, Loughborough University. ISBN 1 901786 51 X Electronic Journals and User Behaviour: Learning for the Future from the SuperJournal Project by David Pullinger and Christine Baldwin Deedot Press, 2002, £14.95. ISBN 0‐954‐2924‐0‐5 Electronic Ecology: A Case Study of Electronic Journals in Context by Karla L. Hahn Association of Research Libraries, 79 pp., 2001, $45. ISBN 0‐918006‐46‐1 The Transition from Paper: Where Are We Going and How Will We Get There edited by R. Stephen Berry and Anne Simon Moffat American Academy of Arts and Sciences, published online (2001): www.amacad.org/publications/trans.htm The Transition from Paper: Where Are We Going and How Will We Get There edited by R. Stephen Berry and Anne Simon Moffat American Academy of Arts and Sciences, published online (2001): www.amacad.org/publications/trans.htm E‐Serials, Publishers, Libraries, Users and Standards, 2nd edn, edited by Wayne Jones The Haworth Press Inc., 2003, 294 pp. paperback ISBN 0789012294  相似文献   
72.
Predicting whether higher education systems will lead to wider and more equitable participation calls for multiple perspectives going outside the European and Anglophone worlds, and beyond looking education also to other sub‐systems of society and government. This reminds us to consider need as well as supply and demand, the importance of place and regions, and the new salience of ‘engagement’, as well as the vital importance of different cultural contexts for what they determine and allow for universalising higher education systems. More or less deep‐reaching curriculum changes may occur. Seven different possible models for the future of HE are proposed, concluding with a prognosis as to what scenario is likely to prevail.  相似文献   
73.
The performance and capabilities of Web search engines is an important and significant area of research. Millions of people world wide use Web search engines very day. This paper reports the results of a major study examining the overlap among results retrieved by multiple Web search engines for a large set of more than 10,000 queries. Previous smaller studies have discussed a lack of overlap in results returned by Web search engines for the same queries. The goal of the current study was to conduct a large-scale study to measure the overlap of search results on the first result page (both non-sponsored and sponsored) across the four most popular Web search engines, at specific points in time using a large number of queries. The Web search engines included in the study were MSN Search, Google, Yahoo! and Ask Jeeves. Our study then compares these results with the first page results retrieved for the same queries by the metasearch engine Dogpile.com. Two sets of randomly selected user-entered queries, one set was 10,316 queries and the other 12,570 queries, from Infospace’s Dogpile.com search engine (the first set was from Dogpile, the second was from across the Infospace Network of search properties were submitted to the four single Web search engines). Findings show that the percent of total results unique to only one of the four Web search engines was 84.9%, shared by two of the three Web search engines was 11.4%, shared by three of the Web search engines was 2.6%, and shared by all four Web search engines was 1.1%. This small degree of overlap shows the significant difference in the way major Web search engines retrieve and rank results in response to given queries. Results point to the value of metasearch engines in Web retrieval to overcome the biases of individual search engines.  相似文献   
74.
Many studies have examined associations between children's theory of mind and social behavior with familiar peers, but to date none have examined how theory of mind might relate to behavior toward unfamiliar peers in a play setting. Forty-four 4-year-olds (21 girls, 23 boys) participated in standard theory-of-mind tasks and in a play session with 3 or 4 other children who were unfamiliar. Children were also tested on general vocabulary ability. No relations were found between theory of mind and social engagement. However, positive associations were found between theory of mind and time spent observing, but not interacting with, other children. Possible explanations of the links between theory of mind, temperament, and social interest are considered.  相似文献   
75.
76.
We provide causal evidence that regulation induced product shocks significantly impact aggregate demand and firm performance in pharmaceutical markets. Event study results suggest an average loss between $569 million and $882 million. Affected products lose, on average, $186 million over their remaining effective patent life. This leaves a loss of between $383 million and $696 million attributable to declines in future innovation. Our findings complement research that shows drugs receiving expedited review are more likely to suffer from regulation induced product shocks. Thus, it appears we may be trading off quicker access to drugs today for less innovation tomorrow. Results remain robust to variation across types of relabeling, market sizes, and levels of competition.  相似文献   
77.
This paper addresses the role that scientific status plays in initial public offerings of technology focused firms. The paper builds on the literature of the sociology of science as well as the work of Spence (1974) and Podolny (1993) and argues that the presence of a Nobel laureate affiliated with a firm making an IPO provides a signal of firm quality to potential investors. Moreover, and building on the work of Podolny and Scott Morton (1999) and Stuart et al. (1999) we hypothesize that the importance of status diminishes as other measures of firm quality become available. We test our hypothesis for two periods of initial public offerings in biotechnology. We document that there is a clear difference in “maturity” of the firms across the two windows on a number of metrics. Consistent with our hypothesis that Nobel laureates play an important role as a non-financial signal of firm quality, we find that first-window firms with a Nobel laureate affiliate realize greater IPO proceeds in the amount of $24 million. In the second window the amount of money raised is not significantly different between Nobel and non-Nobel firms. This finding is consistent with the signaling literature that argues that the importance of a signal is inversely related to the availability of cogent information on firm quality. Consistent with this view, we also find a change between the two windows in the importance of other non-financial metrics used to convey value. Our research is one of the first to examine the dynamic nature of signals. Because we are unable to distinguish the extent to which the reduction in uncertainty at the firm level is correlated with the reduction of uncertainty at the industry level, the question remains as to the extent to which the diminished importance of signals in our second period is due to a change in market uncertainty versus a change in firm uncertainty.  相似文献   
78.
The critical task of predicting clicks on search advertisements is typically addressed by learning from historical click data. When enough history is observed for a given query-ad pair, future clicks can be accurately modeled. However, based on the empirical distribution of queries, sufficient historical information is unavailable for many query-ad pairs. The sparsity of data for new and rare queries makes it difficult to accurately estimate clicks for a significant portion of typical search engine traffic. In this paper we provide analysis to motivate modeling approaches that can reduce the sparsity of the large space of user search queries. We then propose methods to improve click and relevance models for sponsored search by mining click behavior for partial user queries. We aggregate click history for individual query words, as well as for phrases extracted with a CRF model. The new models show significant improvement in clicks and revenue compared to state-of-the-art baselines trained on several months of query logs. Results are reported on live traffic of a commercial search engine, in addition to results from offline evaluation.  相似文献   
79.
The agreement between self-reported and objective estimates of activity energy expenditure was evaluated in adolescents by age, sex, and weight status. Altogether, 403 participants (217 females, 186 males) aged 13-16 years completed a 3-day physical activity diary and wore a GT1M accelerometer on the same days. Partial correlations (controlling for body mass) were used to determine associations between estimated activity energy expenditure (kcal · min(-1)) from the diary and accelerometry. Differences in the magnitude of the correlations were examined using Fisher's r to z transformations. Bland-Altman procedures were used to determine concordance between the self-reported and objective estimates. Partial correlations between assessments of activity energy expenditure (kcal · min(-1)) did not differ significantly by age (13-14 years: r = 0.41; 15-16 years: r = 0.42) or weight status (normal weight: r = 0.42; overweight: r = 0.39). The magnitude of the association was significantly affected by sex (Δr = 0.11; P < 0.05). The agreement was significantly higher in males than in females. The relationship between activity energy expenditure assessed by the objective method and the 3-day diary was moderate (controlling for weight, correlations ranged between 0.33 and 0.44). However, the 3-day diary revealed less agreement in specific group analyses; it markedly underestimated activity energy expenditure in overweight/obese and older adolescents. The assessment of activity energy expenditure is complex and may require a combination of methods.  相似文献   
80.
The purpose of this study was to examine whether the relationships between contextual factors (i.e., autonomy-supportive vs. controlling coaching style) and person factors (i.e., autonomous vs. controlled motivation) outlined in self-determination theory (SDT) were related to prosocial and antisocial behaviors in sport. We also investigated moral disengagement as a mediator of these relationships. Athletes' (n = 292, M = 19.53 years) responses largely supported our SDT-derived hypotheses. Results indicated that an autonomy-supportive coaching style was associated with prosocial behavior toward teammates; this relationship was mediated by autonomous motivation. Controlled motivation was associated with antisocial behavior toward teammates and antisocial behavior toward opponents, and these two relationships were mediated by moral disengagement. The results provide support for research investigating the effect of autonomy-supportive coaching interventions on athletes' prosocial and antisocial behavior.  相似文献   
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