首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   311篇
  免费   3篇
  国内免费   1篇
教育   190篇
科学研究   33篇
各国文化   10篇
体育   57篇
文化理论   5篇
信息传播   20篇
  2023年   1篇
  2022年   6篇
  2021年   12篇
  2020年   14篇
  2019年   11篇
  2018年   25篇
  2017年   17篇
  2016年   16篇
  2015年   14篇
  2014年   23篇
  2013年   67篇
  2012年   12篇
  2011年   11篇
  2010年   12篇
  2009年   5篇
  2008年   6篇
  2007年   7篇
  2006年   2篇
  2005年   9篇
  2004年   3篇
  2003年   6篇
  2002年   3篇
  2001年   3篇
  2000年   2篇
  1999年   2篇
  1998年   2篇
  1996年   1篇
  1995年   2篇
  1994年   1篇
  1993年   1篇
  1992年   3篇
  1991年   1篇
  1990年   2篇
  1989年   2篇
  1985年   1篇
  1984年   2篇
  1983年   2篇
  1980年   1篇
  1978年   1篇
  1977年   2篇
  1975年   1篇
  1974年   1篇
排序方式: 共有315条查询结果,搜索用时 31 毫秒
151.
This study combines minority stress and ecological perspectives to theorize the associations between adolescents’ sexual orientation and time use. Hypotheses are tested using data from a national sample of Australian adolescents aged 14–15 years (Longitudinal Study of Australian Children;= 3,060). Compared to heterosexual adolescents, sexual minority adolescents spent less time with their siblings and fathers, more time alone, less time in active leisure- and school-based activities, and more time in nonactive leisure. There were no differences between sexual minority and heterosexual adolescents in time spent with mothers, peers, and in screen-based leisure. Some associations were gendered. Collectively, the results suggest that sexual minority adolescents may withdraw or be excluded from critical developmental activities and the company of key social partners.  相似文献   
152.
153.
Although the school ICT coordinator’s role has been institutionally defined by the Andalusian Education Administration (Spain), individual factors may be key in the emerging role-building process. Multidimensional scaling (MDS) of the priority given by coordinators to their different functions and a subsequent cluster analysis of the MDS solution were used to identify role orientations among ICT coordinators in primary schools of Andalucía (Spain). Three orientation clusters were identified: “support of ICT use in the classroom” (67.1%), “promote ICT use in the classroom” (17.8%) and “planning and maintenance of ICT equipment in the school” (15.1%). The interest in separating technical and pedagogical duties into two profiles and the perceived organisational support from the Teachers Centres (TCs) differed in the three role orientation types. Finally, strategies are suggested to reduce role ambiguity and role conflict in ICT coordinators. A clearer definition of the role would improve their leadership in ICT implementation in schools.  相似文献   
154.
There is not a unique attitude towards the implementation of digital technology in educational sceneries. This paper aims to validate an adaptation of the DeLone and McLean information systems success model in the context of a learning management system. Furthermore, this study means to prove (1) the necessity of segmenting students in order to fit the model more accurately and (2) the impact of other new Internet tools on students’ perceptions with regard to learning management systems. Partial least squares has been used to analyse the measurement and the structural model. Subsequently, the Finite Mixture Partial Least Squarestechnique has been employed to examine unobserved heterogeneity and to find users’ segments. The results of this research indicate that to segment between two groups of students is especially useful in order to improve the understanding of the success of a learning management system. This segmentation is made according to the importance which the students attribute to the new Internet tools to support their learning.  相似文献   
155.
Background: Physical activity and self-rated wellbeing have important benefits to health. However, scientific knowledge regarding their relationship among older adults is scarce. Thus, the aim of this study was to examine the associations between physical activity frequency and several dimensions of self-rated wellbeing, in a representative sample of European older adults from 28 countries. Methods: This study is based on the European Social Survey round 6, 2012. It had a total sample size of 12,341 older adults (5100 men, 7241 women) with mean age 73.8?±?6.6 years. Information was collected through a questionnaire, filled-in during an hour-long face-to-face interview. Physical activity was accessed using the question “On how many of the last 7 days you were physically active continuously for 20 minutes or longer?” and six dimensions of self-rated wellbeing were used. Results: Physical activity in the last 7 days was linearly related with all dimension of the self-rated wellbeing and with wellbeing total score for both sexes (men, β?=?0.09, 95% CI: 0.07 to 0.10, p?β?=?0.10, 95% CI: 0.09 to 0.11, p?Conclusions: Physical activity promotion should be stressed as a meaningful strategy to improve people's wellbeing overall. This strategy has special importance when considering the older adult population.  相似文献   
156.
As job markets have been polarizing, firms have been changing their labor inputs. By using matched employer–employee data for Portugal, we examine whether labor market polarization has occurred within or across firms and how labor input upgrades have contributed to overall productivity growth. We develop a firm taxonomy based on worker's occupational data. Firms can be focused on one task – Abstract, Manual or Routine – on a combination of tasks, or none. Results show that Abstract firms are the most productive and their share has increased over time. Manual firms, the least productive, have had a stable share throughout the period. Routine firms have seen their share decline over time. The dynamic decomposition of the estimated productivity reveals that productivity growth is propelled by increased market shares of the most productive incumbents and exiting of the least productive, especially for Abstract firms. Notwithstanding these productivity growth drivers, they fail to avert the productivity stagnation observed in Portugal between 2004 and 2009 due to the overall decline in productivity of incumbent firms, especially Routine. We discuss the policy implications of our results which are relevant to other European economies also lagging behind in terms of knowledge and innovation capabilities.  相似文献   
157.
Strenuous physical exercise of the limb muscles commonly results in damage, especially when that exercise is intense, prolonged and includes eccentric contractions. Many factors contribute to exercise-induced muscle injury and the mechanism is likely to differ with the type of exercise. Competitive sports players are highly susceptible to this type of injury. AM3 is an orally administered immunomodulator that reduces the synthesis of proinflammatory cytokines and normalizes defective cellular immune fractions. The ability of AM3 to prevent chronic muscle injury following strenuous exercise characterized by eccentric muscle contraction was evaluated in a double-blind and randomized pilot study. Fourteen professional male volleyball players from the First Division of the Spanish Volleyball League volunteered to take part. The participants were randomized to receive either placebo (n=7) or AM3 (n=7). The physical characteristics (mean+/-s) of the placebo group were as follows: age 25.7+/-2.1 years, body mass 87.2+/-4.1 kg, height 1.89+/-0.07 m, maximal oxygen uptake 65.3+/-4.2 ml.kg(-1).min(-1). Those of the AM3 group were as follows: age 26.1+/-1.9 years, body mass 85.8+/-6.1 kg, height 1.91+/-0.07 m, maximal oxygen uptake 64.6+/-4.5 ml.kg(-1).min(-1). All participants were evaluated for biochemical indices of muscle damage, including concentrations of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, creatine kinase (CK) and its MB fraction (CK-MB), myoglobin, lactate dehydrogenase, urea, creatinine and gamma-glutamyltranspeptidase, both before and 30 days after treatment (over the peak of the competitive season). In the placebo group, competitive exercise (i.e. volleyball) was accompanied by significant increases in creatine kinase (494+/-51 to 560+/-53 IU.l(-1), P < 0.05) and myoglobin (76.8+/-2.9 to 83.9+/-3.1 microg.l(-1), P < 0.05); aspartate aminotransferase (30.8+/-3.0 to 31.1+/-2.9 IU.l(-1)) and lactate dehydrogenase (380+/-31 to 376+/-29 IU.l(-1)) were relatively unchanged after the 30 days maximum effort. AM3 not only inhibited these changes, it led to a decrease from baseline serum concentrations of creatine kinase (503+/-49 to 316+/-37 IU.l(-1), P < 0.05) and myoglobin (80.1+/-3.2 to 44.1+/-2.6 IU.l(-1), P < 0.05), as well as aspartate aminotransferase (31.1+/-3.3 to 26.1+/-2.7 IU.l(-1), P < 0.05) and lactate dehydrogenase (368+/-34 to 310+/-3 IU.l(-1), P < 0.05). The concentration of CK-MB was also significantly decreased from baseline with AM3 treatment (11.6+/-1.2 to 5.0+/-0.7 IU.l(-1), P < 0.05), but not with placebo (11.4+/-1.1 to 10.8+/-1.4 IU.l(-1)). In conclusion, the use of immunomodulators, such as AM3, by elite sportspersons during competition significantly reduces serum concentrations of proteins associated with muscle damage.  相似文献   
158.
This paper introduces a new relational capital framework providing a relationships typology between significant agents in an organizational context and offers an integrated approach to understand relationships as a key element of organizations. Some theoretical contributions in literature on strategy and organization are considered. Following this trend, our paper proposes a general relationships classification considering the four essential relationship properties and shows that these are fundamental for the development and existence of K-events during organizational activities. Based on the elements of K-events during a relationship between significant agents, we propose that the quality of any relationship, at any level of analysis, relies on the development and measurement of certain combinations of variables that are embedded in four different categories. This study explicitly shows some possible theoretical segmentation criteria or theoretical dichotomies for analyzing the concept of relationship between agents. For theorists, it provides a conceptual base for the relationships typology, and for practitioners it identifies key elements for optimal value exchanges.  相似文献   
159.
This study proposes the codification of lexical information in electronic dictionaries, in accordance with a generic and extendable XML scheme model, and its conjunction with linguistic tools for the processing of natural language. Our approach is different from other similar studies in that we propose XML coding of those items from a dictionary of meanings that are less related to the lexical units. Linguistic information, such as morphology, syllables, phonology, etc., will be included by means of specific linguistic tools. The use of XML as a container for the information allows the use of other XML tools for carrying out searches or for enabling presentation of the information in different resources. This model is particularly important as it combines two parallel paradigms—extendable labelling of documents and computational linguistics—and it is also applicable to other languages. We have included a comparison with the labelling proposal of printed dictionaries carried out by the Text Encoding Initiative (TEI). The proposed design has been validated with a dictionary of more than 145 000 accepted meanings.  相似文献   
160.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号