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   13567篇
  免费   125篇
  国内免费   159篇
教育   10728篇
科学研究   1148篇
各国文化   181篇
体育   473篇
综合类   696篇
文化理论   9篇
信息传播   616篇
  2024年   1篇
  2023年   28篇
  2022年   66篇
  2021年   132篇
  2020年   204篇
  2019年   141篇
  2018年   142篇
  2017年   104篇
  2016年   131篇
  2015年   266篇
  2014年   654篇
  2013年   833篇
  2012年   1100篇
  2011年   1011篇
  2010年   761篇
  2009年   674篇
  2008年   776篇
  2007年   1034篇
  2006年   982篇
  2005年   963篇
  2004年   837篇
  2003年   817篇
  2002年   623篇
  2001年   529篇
  2000年   334篇
  1999年   107篇
  1998年   42篇
  1997年   29篇
  1996年   34篇
  1995年   19篇
  1994年   22篇
  1993年   7篇
  1992年   6篇
  1991年   3篇
  1990年   4篇
  1989年   1篇
  1988年   2篇
  1986年   2篇
  1985年   62篇
  1984年   65篇
  1983年   54篇
  1982年   48篇
  1981年   47篇
  1980年   11篇
  1979年   25篇
  1978年   46篇
  1977年   36篇
  1976年   36篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
在计划行为理论(TPB)的基础上,引入身体活动习惯行为与执行意向,构建扩展TPB(METPB)模型,检验该模型对9~19岁青少年群体的中高强度身体活动(MVPA)的适用性,探讨该模型对小学、初中及高中阶段青少年MVPA影响的差异。结果显示:假设模型的拟合度可以接受,纳入习惯行为与执行意向后,METPB显著地提高了其对身体活动行为的解释力。态度和感知行为控制对MVPA行为意向有显著性影响,解释了31.4%的行为意向方差;行为意向和习惯行为对MVPA行为有显著性影响,解释了18.7%的行为方差;执行意向加强了行为意向朝实际行为的转换。METPB模型对于不同学习阶段青少年MVPA意向及行为的影响有显著性差异。其中:主观规范对小学生与初中生MVPA意向产生了显著性影响,而对高中生的MVPA意向并无显著性影响;感知行为控制对3个阶段学生的MVPA意向产生的影响随着学习阶段的上升不断增强。建议:在对于青少年身体活动的干预中,政府、家庭、学校应重视培养学生对于身体活动参与的正确态度,提高其参与身体活动的意愿,培养其参与身体活动的行为习惯,且在对青少年身体活动干预时考虑学习阶段的差异。  相似文献   
2.
ABSTRACT

In times of globalization we are facing a crisis of care. The invisibility of relations of domination and oppression against nature, women and girls, as well as the elderly, generate inequalities and structural problems that increase the unsustainability of life on the planet. The uncertainty towards the future, generated by climate change, pollution and scarcity of water resources, is leading us towards war or revolution – a revolution that requires the involvement of the new generations to transform reality and confront contemporary problems. In this sense, it is necessary to educate, raise awareness and empower girls and boys in citizen participation, in overcoming gender inequalities and in the development of fairer and more sustainable practices and behaviours. The participatory action-research experience with social cartography ‘From the Body to the City’, promoted by the Institute of Innovation and Knowledge Management – INGENIO (CSIC-UPV) in collaboration with the primary school CEIP Vicente Gaos of Valencia (Spain), developed together with the students of 4th primary grade, intended to reflect and act collectively on our territories from the principles of transformative education and global citizenship.  相似文献   
3.
ABSTRACT

We present the determinants of the length of stay (LOS) of Porto Street Stage that integrated the program of the 52nd edition of Rally de Portugal. Sport events assume an important role in the marketing of tourism destinations. However, when we compare them with other segments in tourism, it still remains underexplored. This study represents an opportunity to contribute to the literature, and it could become a significant toll for the organizers, public entities and other stakeholders. We contemplate a set of information and data that may improve the management of the future editions in a more rigorous and effective way. As we are dealing with an international event, it is an occasion to enlist tourists and promote the tourist destination. We applied a quantitative analysis and considered the sociodemographic characteristics of the spectators, factors that influenced the trip, expenses per day in the city, level of satisfaction with the event, and the intention to return. An OLS regression model, a Weibull survival model and a zero-truncated negative binomial regression model were estimated, and the results were compared. On the LOS determinants it is not common to consider the influence of each item of expenditure during the stay and the satisfaction levels with the event and different effects were observed. The travel and accommodation expenditures present a negative effect on the LOS. In the opposite side the satisfaction level and intention to return, both present a positive effect on the LOS. The sociodemographic characteristics have diverse impacts on the LOS.  相似文献   
4.
BackgroundOne-hour postprandial hyperglycemia is associated with increased risk of type 2 diabetes and cardiovascular disease. Physical activity (PA) has short-term beneficial effects on post-meal glucose response. This study compared the oral glucose tolerance test results of 3 groups of people with habitually different levels of PA.MethodsThirty-one adults without diabetes (age 25.9 ± 6.6 years; body mass index 23.8 ± 3.8 kg/m2; mean ± SD) were recruited and divided into 3 groups based on self-reported PA volume and intensity: low activity < 30 min/day of moderate-intensity activity (n = 11), moderately active ≥ 30 min/day of moderate-intensity PA (n = 10), and very active ≥ 60 min/day of PA at high intensity (n = 10). Participants completed an oral glucose tolerance test (50 g glucose) with capillary blood samples obtained at baseline, 15 min, 30 min, 45 min, 60 min, 90 min, and 120 min post-ingestion.ResultsThere were no significant differences between groups for age or body fat percentage or glycated hemoglobin (p > 0.05). The groups were significantly different in terms of baseline glucose level (p = 0.003) and, marginally, for gender (p = 0.053) and BMI (p = 0.050). There was a statistically significant effect of PA on the 1-h postprandial glucose results (p = 0.029), with differences between very active and low activity groups (p = 0.008) but not between the moderately active and low activity groups (p = 0.360), even when baseline glucose level and gender differences were accounted for. For incremental area under the curve there was no significant effect of activity group once gender and body fat percentage had been accounted for (p = 0.401). Those in the low activity group took 15 min longer to reach peak glucose level than those in the very active group (p = 0.012).ConclusionThe results suggest that high levels of PA have a beneficial effect on postprandial blood glucose profiles when compared to low and moderate levels of activity.  相似文献   
5.
“全面二孩”政策的实施对大多数女性的生活和生育产生了很大的影响。大多数生育后的女性要面临的一个重要选择就是出去就业还是在家带孩子?运用社会性别理论提出假设:大多数妇女育后选择是否就业主要取决于丈夫的家庭利益,而不是其个人的就业意愿;城镇已婚育龄妇女就业意愿对其育后就业决策更有积极影响;教育程度高的已婚育龄妇女就业意愿对其育后就业决策更有积极影响。通过实证研究和二元logistic回归模型分析,结果显示,三个假设都得到了部分验证。  相似文献   
6.
采用文献资料法等研究方法对新时代我国少数民族地区体育公共服务分层治理进行研究,旨在为提高我国少数民族地区体育公共服务质量和建设体育强国提供建议。研究认为,少数民族地区体育公共服务分层治理是基于我国社会分层的现状以及各阶层体育需求和参与特征存在的差异而采取的差异性治理方式,分层治理有"因层制宜"的意蕴,有利于促进我国少数民族地区体育公共服务均等化和改变少数民族地区体育公共服务"供给不足"和"供非所需"的困境。现阶段我国少数民族地区体育公共服务分层治理的思路包括明确少数民族地区体育公共服务分层治理主体责任、完善少数民族地区体育公共服务分层治理资金保障机制、积极探索少数民族地区体育公共服务分层供给方式、构建少数民族地区体育公共服务分层治理协商机制、建立少数民族地区体育公共服务分层供给绩效评价体系。  相似文献   
7.
China's 'tidal wave' of rural to urban migration has had a tremendous impact on the educational outcomes of its children. It remains unexplored how and when do migrant children’s experience of acculturation following arrival in the place of settlement influence their academic achievement. This study used a stratified cross-sectional sample of 2412 Chinese migrant children and adolescents aged 10–18 (Mean = 14, 45 % female) to investigate the role of school satisfaction and family closeness in the relationship between acculturation patterns and academic achievement. Acculturation patterns are derived from the bidimensional model proposed by Berry (2005). The results indicated that integration had a positive association with concurrent academic achievement. School satisfaction was a mediator between integration and academic achievement. Furthermore, the full mediation of school satisfaction was only supported when there was a high level of family closeness. Findings from this study underline the usefulness of the bi-dimensional model in understanding the individual differences in academic achievement and suggest greater attention to the cultural variations in interpersonal functioning at the family and school context.  相似文献   
8.
运用文献资料、实地调查等研究方法,对我国高校体育场馆对外开放突发事件应急管理现状进行调查分析。发现目前我国高校体育场馆对外开放过程中,存在缺乏突发事件应急预案的研制、对安全风险评估不足、缺乏急救设施的配置、场馆现场管理人员缺乏应急管理的培训与演练、场馆现场管理人员数量不足的问题。在高校体育场馆突发事件应急管理发展现状基础上,依托应急管理理论与应急救援理论,架构由突发事件识别与评估模块、决策系统模块、应急救助体系模块、应急预案选择模块、应急救援的执行模块所组成的我国高校体育场馆对外开放突发事件应急管理机制。建议:完善场馆管理规章制度,形成场馆对外开放突发事件应急长效管理机制;加强员工的应急管理理论培训与技能学习;制定各类应急预案并进行演练;保持突发事件应急救援稳定的对外联系畅通。  相似文献   
9.
《Sport Management Review》2019,22(4):502-512
The physical environment of sport facilities, referred to as the sportscape, has a substantial influence on the extent to which sport fans attend sporting events and revisit the facilities. Accordingly, professional franchises make efforts to construct new stadiums with different sportscape elements, which serve as important factors that determine spectators’ levels of attendance satisfaction. With a sample of South Korean baseball fans, the authors examine which sportscape components of professional ballparks are considered most important by spectators, as well as how baseball attendees indicate their willingness to pay for particular sportscape attributes. Based on a discrete choice experimental approach, results indicate that spectators place the greatest importance on fast access to ballparks largely dependent upon the location. Results also suggest that respondents are willing to pay KR₩4102 for one more subway line. Different strategies for developing successful sportscape components are discussed.  相似文献   
10.
BackgroundMicroalgae are microorganisms that produce various products, for example, pigments, mainly carotenoids. This study aimed to used the strain of Muriellopsis sp. and to evaluate their behavior when grown in freshwater and seawater, along with indoor and outdoor conditions for both cultures. Growth of the strain was evaluated by determining its biomass, lutein productivity with high-performance liquid chromatography (HPLC), and antioxidant activity by using the 2,2-diphenyl-1-picrilhydrazil (DPPH method).ResultsMuriellopsis sp. strain in indoor cultures showed an increased antioxidant activity. In outdoor conditions, both cultures showed increased cells number, concentration of biomass, and lutein productivity. The percentage of lutein obtained from the strain MCH in indoor conditions was 25 times higher than that reported for calendula, reaching 0.75% of lutein in Muriellopsis sp. cultured in seawater, followed by 0.6% in Muriellopsis sp., cultures in freshwater at day 12 of both cultures. These values exceed that of microalgae Scenedesmus almeriensis, which reaches 0.53% lutein.ConclusionsThe results show that the native strain of the Atacama Desert is one of the largest producers of lutein as compared to those reported to date. The study demonstrated the feasibility of producing this carotenoid with well-known properties to prevent some diseases due to its high nutritional value. Muriellopsis sp. cultivation in open-air seawater is a good precedent for developing mass production of this species in an area where freshwater is scarce and costly.How to cite: Cruz-Balladares V, Marticorena P, Riquelme C. Effect on growth and productivity of lutein from the chlorophyta microalga, strain MCH of Muriellopsis sp., when grown in sea water and outdoor conditions at the Atacama Desert. Electron J Biotechnol 2021;54. https://doi.org/10.1016/j.ejbt.2021.09.001  相似文献   
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