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   555篇
  免费   4篇
教育   366篇
科学研究   39篇
各国文化   6篇
体育   90篇
文化理论   14篇
信息传播   44篇
  2023年   3篇
  2022年   7篇
  2021年   18篇
  2020年   21篇
  2019年   41篇
  2018年   39篇
  2017年   41篇
  2016年   38篇
  2015年   21篇
  2014年   21篇
  2013年   119篇
  2012年   20篇
  2011年   14篇
  2010年   19篇
  2009年   9篇
  2008年   12篇
  2007年   11篇
  2006年   14篇
  2005年   7篇
  2004年   8篇
  2003年   9篇
  2002年   3篇
  2001年   3篇
  2000年   3篇
  1999年   7篇
  1998年   3篇
  1997年   4篇
  1996年   4篇
  1995年   1篇
  1994年   5篇
  1993年   9篇
  1992年   2篇
  1991年   5篇
  1990年   2篇
  1989年   2篇
  1987年   1篇
  1986年   1篇
  1982年   1篇
  1979年   1篇
  1978年   1篇
  1976年   1篇
  1975年   1篇
  1974年   2篇
  1970年   2篇
  1931年   1篇
  1927年   1篇
  1892年   1篇
排序方式: 共有559条查询结果,搜索用时 0 毫秒
551.
Resumen

En la perspectiva metodológica de la Psicologia Ecológica y en su consideración de la clase como unidad ambiental, el presente artículo hace referenda a una investigación sobre los diferentes modos de ocupación/interacción de dos grupos de parvulario con características diferenáadas (procedencia social y cultural, ubicación del edificio, actitud pedagógica…) con los equipamientos que conforman en entorno-clase.

La ocupación viene definida por (a) el número de desplazamientos que realiza cada alumno, (b) los objetos a los que se dirige y (c) la significación que va unida a cada desplazamiento.

Las conclusiones derivadas de los resultados obtenidos evidencian diferencias entre los dos grupos en relación (1) con el modo de organización de la clase en función de la actitud pedagógica del profesor (2) con el papel que adquiere la maestra por la referencia del 45% de las interacciones que se originan en cada grupo.  相似文献   
552.
This article summarises research carried out between 2006 and 2008 by IPTS (Institution for Prospective Technological Studies) in collaboration with a consortium of experts from 10 member states, led by ICEGEC. The project gathered information on eLearning developments to assess drivers and barriers and to suggest implications for policy and research in the 10 member states that joined the European Union in 2004. Three examples of countries (Estonia, Hungary and Slovenia) demonstrate that, while the group is not homogeneous, commonalities can be detected. Reports show that all the EU10 countries have been catching up with the older member states in ICT penetration and skills, but large digital divides remain due to regional, social and economic divides. Educational institutions are equipped with ICT, but not always at the same level in classrooms as in EU15. Universities are using ICT in education, but mostly for material provision purposes. Enterprises seem to have higher usage of eLearning solutions than in EU15, but these are not equally available for all employees. Lack of focus and coordination in policies to support eLearning developments has been assessed to be a major barrier. In general, EU10 seems to be facing similar challenges to other European countries, although specific efforts are needed to help close the divides and engage people in lifelong learning with the new opportunities ICT could provide.  相似文献   
553.
Age based school entry laws force parents and educators to consider an important tradeoff: though students who are the youngest in their school cohort typically have poorer academic performance, on average, they have slightly higher educational attainment. In this paper we document that for a large cohort of California and Texas natives the school entry laws increased educational attainment of students who enter school early, but also lowered their academic performance while in school. However, we find no evidence that the age at which children enter school effects job market outcomes, such as wages or the probability of employment. This suggests that the net effect on adult labor market outcomes of the increased educational attainment and poorer academic performance is close to zero.  相似文献   
554.
ABSTRACT

This study aimed to analyze the acute effect of inter-repetition rest (IRR) intervals on mechanical and metabolic response during four resistance exercise protocols (REPs). Thirty resistance-trained men were randomly assigned to: continuous repetitions (CR), 10 s (IRR10) or 20 s (IRR20) inter-repetition rest. The REPs consisted of 3 sets of 6, 5, 4 and 3 repetitions against 60, 70, 75 and 80% 1RM, respectively, in the full squat exercise. Muscle fatigue was assessed using: percentage of velocity loss over three sets, percentage of velocity loss against the ~1 m·s?1 load (V1 m·s?1), and loss of countermovement jump (CMJ) height pre-post exercise. Blood lactate was measured before and after exercise. The percentage of velocity loss over three sets and lactate concentration were significantly lower (< 0.05) for IRR groups compared to CR in all REPs. The CR group showed a significantly higher (< 0.05) velocity loss against V1 m·s?1 load and loss of CMJ height pre-post exercise than IRR groups in REP against 60% 1RM. In conclusion, both IRR groups produced a significant lower degree of fatigue compared to CR group. However, no significant differences were found in any measured variables between IRR configurations.  相似文献   
555.
This paper analyses the representations held by adolescents and university students in relation to the mechanism for explaining changes in matter (changes of state, dissolutions, expansions and chemical reactions) in terms of the kinetic theory. The answers to a questionnaire were analysed by considering the proportion of correct answers and the use of alternative conceptions. The results show that understanding of explanatory mechanisms of changes in matter is affected by age and instruction level and content of the problem. The main conception that competes with the kinetic model is the attribution to the particles of the changes observed, at a macroscopic level. This is more evident in changes of state and expansions than in other changes. This confusion results from a failure to differentiate properly between the represented reality and the model that represents it. In conclusion, analysis has shown once more students' difficulties in going beyond apparent reality or integrating the data obtained from it into the scientific models they learn at school.  相似文献   
556.
Microrheometry is very important for exploring rheological behaviours of several systems when conventional techniques fail. Microrheometrical measurements are usually carried out in microfluidic devices made of Poly(dimethylsiloxane) (PDMS). Although PDMS is a very cheap material, it is also very easy to deform. In particular, a liquid flowing in a PDMS device, in some circumstances, can effectively deform the microchannel, thus altering the flow conditions. The measure of the fluid relaxation time might be performed through viscoelasticity induced particle migration in microfluidics devices. If the channel walls are deformed by the flow, the resulting measured value of the relaxation time could be not reliable. In this work, we study the effect of channel deformation on particle migration in square-shaped microchannel. Experiments are carried out in several PolyEthylene Oxyde solutions flowing in two devices made of PDMS and Poly(methylmethacrylate) (PMMA). The relevance of wall rigidity on particle migration is investigated, and the corresponding importance of wall rigidity on the determination of the relaxation time of the suspending liquid is examined.  相似文献   
557.
Abstract

Currently, direct empirical evidence exists about the amount of mechanical load that climbers apply to each finger during several hand grips specific to sport climbing, but not yet in a specific hanging position.

The objectives of this study are a) to draw and build a solid and rigid support that simulates the real action of a hand grip in a hanging position in sport climbing, to enable the measurement of the mechanical load endured by the fingers in a hanging position and in addition, b) to describe the distribution of mechanical load among fingers as a function of the level of climbing during different hand grips in a hanging position.

Thirty young male participants took part in the initial phase of reliability of the measurements, while another 64 male climbers participated in the subsequent study phase to check the relations between independent and dependent variables. The level of on sight climbing and the total practice experience were used to define the groups. The research task consisted of performing hanging positions on the created support in order to measure the mechanical load endured by the fingers in the three most characteristic hand grips in climbing (crimp, half crimp and slope). It has been concluded that the performance level of the climbers had no influence on the production of a pattern of differentiated finger mechanical load during the research task.  相似文献   
558.
While there is strong support of the usefulness of post-activation potentiation (PAP) phenomenon in power demanding sports, the role that PAP could play in endurance sports has received less attention. The aim of this review is to present evidence for a better understanding of PAP in endurance athletes; and to discuss the physiological basis and methodological aspects necessary for better practices and designing further studies. A search for relevant articles on PAP and endurance trained athletes was carried out using Medline and ISI Web of Knowledge databases. Twenty-two studies were included in the review. The current evidence suggests the possible influence of PAP for performance enhancement after appropriate conditioning activities during warm up. Evaluation of PAP responses during testing, training and competition may be also important for athletes monitoring. There are many unresolved questions about the optimum load parameters for benefiting from PAP in both training and competition; and the role that PAP may exert for optimal performance while interacting with central and peripheral factors associated with muscle fatigue. Further studies should elucidate the association between PAP responses and long-term adaptations in endurance athletes.  相似文献   
559.
This study analysed the acute mechanical and metabolic responses to a sprint training session focused on maintaining maximal speed until a given speed loss was reached. Nine male high-level sprinters performed 60 m running sprints up to a 3% in speed loss with 6 min rests between sets. Mechanical responses (countermovement jump (CMJ) height and speed loss) and metabolic responses (blood lactate and ammonia concentrations) were measured pre-exercise and after each set was performed. Jump height loss showed almost perfect relationships with both lactate (r = 0.91) and ammonia (r = 0.91) concentrations. In addition, nearly perfect relationships were observed for each athlete between CMJ height loss and lactate (r = 0.93–0.99) and ammonia (r = 0.94–0.99). Very large correlations were found between speed loss and lactate (r = 0.83), and ammonia (r = 0.86) concentrations. Furthermore, close relationships were observed for each athlete between speed loss and lactate (r = 0.86–0.99), and ammonia (r = 0.88–0.98). These results suggest that the CMJ test may allow more accurate setting of training loads in sprint training sessions, by using an individualised sprint dose based on mechanical and physiological responses rather than a standard fixed number of sprints for all athletes.  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