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81.
Background:Football is the most practised sport in the world and is associated with the risk of injuries in the players.Some studies have been published that identify injury prevention programs,but there is no review of the full body of evidence on injury prevention programs for use by football coaches.The aim of this article was to carry out a systematic review of published studies on injury prevention programs for adult male footballers,identify points of common understanding and establish recommendations that should be considered in the design of injury prevention strategies.Methods:PubMed and EMBASE databases were used to identify relevant published articles using the following keywords:"soccer"AND"injury"AND"prevention".Results:A total of 2512 studies were identified initially,but only 11 studies met the inclusion criteria,and their outcomes are presented.Results revealed that injury prevention programs in football have focused on strength training,proprioceptive training,multicomponent programs(balance,core stability,and functional strength and mobility),and warm-up programs.Conclusion:Based on results from the studies analyzed,football players can lower the incidence of match and training injuries by participating in dynamic warm-up programs that include preventive exercises before games or during training sessions,and by adding strength,balance,and mobility training to the training sessions.  相似文献   
82.
Tensiomyography has been suggested as an indirect marker of muscle stiffness, which is associated with strength/power performance. Therefore, it is reasonable to suggest that tensiomyography parameters could be associated with power-related motor tasks. The purpose of this study was to investigate the association between tensiomyography parameters (from rectus and biceps femoris) and jumping and sprinting abilities in elite soccer players. In addition, we used tensiomyography parameters to compare the lateral symmetry between dominant and non-dominant legs. Twenty elite soccer players (age: 23.3 ± 4.8 years; height: 183.5 ± 6.6 cm; weight: 77.8 ± 7.5 kg) volunteered to participate in the study. Significant moderate negative correlations between biceps femoris displacement and contact time (r = –0.5, p = 0.03), rectus femoris displacement and contact time (r = –0.51, p = 0.02), and a significant moderate correlation between biceps femoris displacement and reactive strength index (r = 0.5, p = 0.03) were found. There were no correlations between tensiomyography parameters and power-related motor tasks. In addition, no differences in tensiomyography parameters between dominant and non-dominant legs were found. Our data suggest that tensiomyography parameters are not associated with power-related motor tasks performance in elite soccer players.  相似文献   
83.
Abstract

The aims of the present study were (1) to analyse the physical demands of top-class referees and (2) to compare their official FIFA fitness test results with physical performance during a match. The work rate profiles of 11 international referees were assessed during 12 competitive matches at the 2003 FIFA Under-17 World Cup and then analysed using a bi-dimensional photogrammetric video analysis system based on direct lineal transformation (DLT) algorithms. In the first 15 min of matches, the referees were more active, performing more high-intensity exercise (P < 0.01) than in the first 15 min of the second half. During the second half of matches, the referees covered a shorter distance (P < 0.01), spent more time standing still (P < 0.05), and covered less ground cruising (P < 0.05), sprinting (P < 0.05), and moving backwards (P < 0.001) than in the first half. Also in the second 45 min, the distance of referees from infringements increased (P < 0.05) in the left attacking zone of the filed. There was also a decrease (P < 0.05) in performance in the period following the most high-intensity activity, compared with the mean for the 90 min. Time spent performing high-intensity activities during a match was not related to performance in the 12-min run (r 2 = 0.30; P < 0.05), the 200-m sprint (r 2 = 0.05; P < 0.05), or the 50-m sprint (r 2 = 0.001; P < 0.05). The results of this study show that: (1) top-class referees experienced fatigue at different stages of the match, and (2) the typical field tests used by FIFA (two 50-m and 200-m sprints, followed by a 12-min run) are not correlated with match activities.  相似文献   
84.
ABSTRACT

This study aimed to investigate the effects of different training modalities on the soluble Klotho (S-Klotho) plasma levels in sedentary middle-aged adults. A total of 74 middle-aged adults (53.4 ± 5.0 years old; 52.7% women) were enrolled in the FIT-AGEING study. We conducted a 12-week randomised controlled trial. The participants were randomly assigned to 4 different groups: (i) a control group (no exercise), (ii) a physical activity recommendation from the World Health Organization group (PAR), (iii) a high intensity interval training group (HIIT), and (iv) a high intensity interval training group adding whole-body electromyostimulation training group (HIIT-EMS). S-Klotho plasma levels, anthropometric measurements, and body composition variables were measured before and after the intervention programme. All exercise training modalities induced an increase in the S-Klotho plasma levels (all P ≤ 0.019) without statistical differences between them (all P ≥ 0.696). We found a positive association between changes in lean mass index and changes in the S-Klotho plasma levels, whereas a negative association was reported between changes in fat mass outcomes and changes in the S-Klotho plasma levels after our intervention study. In conclusion, our results suggest that the link between exercise training and the increase in S-Klotho plasma levels could be mediated by a decrease of fat mass and an increase of lean mass.  相似文献   
85.
Through the analysis of survey and interview data, we investigated the attitudes and perceptions of 32 multilingual teachers of Spanish in Belize, a code-switching (CS) context where Spanish is in intense contact with English and Belizean Kriol. More specifically, we examined teachers’ and students’ attitudes toward Spanish and CS and teachers’ perceptions vis-à-vis students’ attitudes toward Spanish instruction. The study revealed that whereas some teachers held negative views of Northern Belizean Spanish, they did not markedly perceive standard Spanish as “better” than the local variety of Belizean Spanish. The analysis also showed that most teachers had a positive predisposition to the use of CS as a pedagogical tool in their classrooms, a finding that suggests that ultra-normative attitudes toward Spanish varieties are not prevalent among these educators. In view of students’ attitudes, teachers concurred that students had overwhelmingly negative attitudes toward standard Spanish, in line with previous findings. We argue that educational reforms and status-planning efforts are vital to destigmatize Spanish and to promote its maintenance alongside Belizean Kriol and English.  相似文献   
86.
This study provides insight in the variety of urban-related challenges that beginning teachers experience in urban schools. Literature on urban teaching focuses on teaching children from low socio-economic status (SES) and/or culturally diverse backgrounds. In many European cities, however, schools are populated by both children from relatively high and from low-SES backgrounds. This study examined the problems and challenges of beginning teachers in Dutch urban primary schools. Teachers were interviewed at schools with different student populations. Results showed that, although many of the challenges that beginning teachers experienced concern the same themes, their actual manifestation differed related to schools’ student populations. For instance, the problem of ‘parental contact’ referred to both the extreme involvement and demands of highly educated wealthy parents at some schools and the diverse backgrounds of parents at other schools. Results of the study can be used to develop adequate preparation and support for beginning urban teachers.  相似文献   
87.
According to Healthy People (2011), in order to understand the health concerns of the Lesbian, Gay, Bisexual, and Transgender (LGBT), the oppression and discrimination that they have faced must be scrutinized. Among the many issues they face, their estrangement experiences are one of the most understudied. However, little is known about how it is experienced by the gay elderly population, hence, this investigation. This grounded theory purports to describe the process by which estrangement is experienced among the Filipino gay older adults. Strauss and Corbin’s Grounded Theory (1990) design was utilized. A total of 10 gay older persons were purposively chosen to participate in semi-structured interviews. Field texts were subjected to thematic analysis involving open, axial, and selective coding. The study generated The Sailing Model of Estrangement. Remarkably, three phases relative to estrangement emerged, namely: sequestering, striving, and surviving. Primarily, the sequestering phase involves the gay persons’ need to express self, search for acceptance, and its subsequent reactions. The striving phase typifies the struggle in dealing with estrangement leading to either feelings of depression, remorse and shame or positivity, hopefulness, and motivation. Finally, in the surviving phase, gay persons may either feel contented and fulfilled or sad, lonely, and remorseful as they acquiesce aging with estrangement. Findings of the study offer an understanding of how Filipino gay older adults employ coping strategies in response to estrangement.  相似文献   
88.
Results are reported in this paper from a study aimed at evaluating significant competencies in final-year students of some engineering programmes in Chile. The study was carried out by a group of eight universities that were interested in exploring ways to assess learning outcomes such as those demanded by the recent Chilean accreditation system. The authors actively participated in all stages of the study, contributing directly to the design, application and results evaluation of some tests. A sample of 150 students was tested, under conditions that guaranteed the comparability of results. In this paper the authors present results relating to the evaluation of effective communication. The study was backed up by a conceptual model and some hypotheses that are explained and discussed in this work.  相似文献   
89.
Queries submitted to search engines can be classified according to the user goals into three distinct categories: navigational, informational, and transactional. Such classification may be useful, for instance, as additional information for advertisement selection algorithms and for search engine ranking functions, among other possible applications. This paper presents a study about the impact of using several features extracted from the document collection and query logs on the task of automatically identifying the users’ goals behind their queries. We propose the use of new features not previously reported in literature and study their impact on the quality of the query classification task. Further, we study the impact of each feature on different web collections, showing that the choice of the best set of features may change according to the target collection.  相似文献   
90.
Moral pride, namely the pride generated by morally positive behaviour, can foster prosocial behaviour. To demonstrate this, two quasi-experimental studies were conducted with nine- to 11-year-old children. Study 1 analysed the effect of the pride felt after engaging in prosocial behaviour, in four classrooms from two different schools (N = 94). Study 2 analysed the effect of the pride generated by the evocation of a past example of one’s own prosocial behaviour, in four classrooms from another school (N = 77). The hypothesis was supported in Study 1 but not in Study 2. Interesting correlations were found between dispositional moral pride (measured using a scale designed ad hoc) and other relevant variables in the moral field: intention to engage in prosocial behaviour, habitual prosocial behaviour and dispositional empathy. In general, these studies attest to the importance of moral pride, both dispositional and that felt in a specific situation, in moral life.  相似文献   
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