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41.
The aim of this study was to examine the impact of contextual factors on relative locomotor and metabolic power distances during professional female soccer matches. Twenty-eight players (forwards, n?=?4; midfielders, n?=?12; defenders, n?=?12) that competed in a 90-min home and away match (regular season only). The generalised estimating equations (GEE) was used to evaluate relative locomotor and metabolic power distances for three contextual factors: location (home vs. away), type of turf (natural vs. artificial), and match outcome (win, loss and draw). No differences were observed for home vs. away matches. Moderate-intensity running (20.0?±?1.0?m?min?1 and 16.4?±?0.9?m?min?1), high-intensity running (8.6?±?0.4?m?min?1 and 7.3?±?0.4?m?min?1) and high-metabolic power (16.3?±?0.5?m?min?1 and 14.4?±?0.5?m?min?1) distances were elevated on artificial turf compared to natural grass, respectively. Relative sprint distance was greater during losses compared with draws (4.3?±?0.4?m?min?1 and 3.4?±?0.3?m?min?1). Overall physical demands of professional women’s soccer were not impacted by match location. However, the elevation of moderate and high-intensity demands while playing on artificial turf may have implications on match preparations as well as recovery strategies.  相似文献   
42.
从国家和地方政策可以发现,体育产业集聚已成为中国体育产业发展的趋势。 然而体育产业集群作为一个复杂的网络主体,其发展与政府固然分不开,其内部组织结构、关系网络的优化才是集群优化的重点。研究创新构建了“网络特征—主体能力—企业绩效”理论模型,客观地揭示了变量之间的关系,并定量地证明了各变量间的相互作用。统计结果显示:体育产业集群的网络结构和网络关系对企业主体有直接的积极影响。体育企业的主体在网络规模与企业绩效、关系实力和企业绩效、关系质量和企业绩效之间具有明显的中介效应,在网络密度与企业绩效、网络开放性和企业绩效之间不具有中介效应。体育企业的主体获取和利用其他实体的资源并将其应用于生产过程将有助于提高企业绩效,对企业绩效的影响最大。研究对政府和体育企业层面分别提出了规范市场秩序、促进网络建设以及增进知识共享、提高网络质量等管理建议。  相似文献   
43.
ABSTRACT

Olfaction has been described as one of the least studied of the senses. This has certainly proven true in Communication. This project applies Ethnography of Communication and Cultural Discourse Analysis to examine the role that olfaction plays in the cultural meaning systems of two speech communities: residents surrounding the Gowanus Canal and bereaved parents. The cultural hub used to explore the cultural significance of olfaction in both speech communities is feeling. The analyses illustrate how emotions are tied to associated sensations and further become activated through radiants of dwelling, relating and acting. The analysis also shows how olfaction may serve to unify and separate members of a community. The significance of this research encourages stretching the boundaries of communication studies by examining the less studied physical senses and the boundaries of Cultural Discourse Analysis by providing distinctions that others can incorporate when examining feelings.  相似文献   
44.
坦桑尼亚是"一带一路"倡议通向非洲、辐射非洲内陆的重要门户,它在快速城市化过程中面临交通基础设施严重短缺问题。基于坦桑尼亚公路、铁路、机场、港口、人口和城市分布数据,运用GIS空间分析技术,结合交通通达指数模型,从县域与城乡两个层面对坦桑尼亚交通通达水平的空间格局特征进行定量分析。研究发现:1)坦桑尼亚县域交通通达水平空间分布极不均衡,高值连片区主要位于东北沿海和维多利亚湖沿岸,低值连片区主要位于中央铁路线中段以北、中央铁路线南部的广大地区;2)受地理区位、资源禀赋、殖民历史、政府政策等影响,城市与乡村地区之间的交通通达水平差异十分显著。研究结果有助于坦桑尼亚制定区域交通发展政策和优化资源配置,同时对中-坦产业精准对接和产能转移具有一定的促进意义。  相似文献   
45.
针对多旋翼无人机目标的识别问题,提出一种基于伽柏(Gabor)变换的瞬时频率估计与快速傅里叶变换(FFT)相结合的微多普勒特征提取算法。首先建立多旋翼无人机旋翼回波模型,并通过仿真分析叶片数目、旋翼转速和初始相位等参数对微多普勒特征的影响,利用Gabor变换得到时频特征。在此基础上通过瞬时频率极大值法提取微多普勒频率,并对瞬时频率采用FFT提取旋翼数和转动频率,从而获得叶片长度估计值。实测数据验证了该算法较为准确地提取无人机的微多普勒参数。  相似文献   
46.
Martin to Brown     
The rise of the modern Black Lives Matter movement can be traced back to two key events, the 2012 death of Trayvon Martin and the 2014 death of Michael Brown. Research routinely showed that mainstream media’s narrative choices marginalize and delegitimize protesters and their causes, a pattern known as the protest paradigm. This study provides a longitudinal examination of how the same mainstream media system varied in their coverage of similar events and the degree to which journalists challenged the predicted paradigms conceptualized in other academic work. A content analysis of national newspaper coverage revealed that news before the judicial rulings focused on protesters’ tactics (violence versus peaceful) and changed to the realm of ideas (grievances and demands) after the assailants were considered not guilty of wrongdoing. No progression was found in legitimizing coverage of protests between the two cases.  相似文献   
47.
48.
The purpose of this study was to investigate kinematic and spatiotemporal variables of aquatic treadmill walking at three different water depths. A total of 15 healthy individuals completed three two-minute walking trials at three different water depths. The aquatic treadmill walking was conducted at waist-depth, chest-depth and neck-depth, while a customised 3-D underwater motion analysis system captured their walking. Each participant’s self-selected walking speed at the waist level was used as a reference speed, which was applied to the remaining two test conditions. A repeated measures ANOVA showed statistically significant differences among the three walking conditions in stride length, cadence, peak hip extension, hip range of motion (ROM), peak ankle plantar flexion and ankle ROM (All p values < 0.05). The participants walked with increased stride length and decreased cadence during neck level as compared to waist and chest level. They also showed increased ankle ROM and decreased hip ROM as the water depth rose from waist and chest to the neck level. However, our study found no significant difference between waist and chest level water in all variables. Hydrodynamics, such as buoyancy and drag force, in response to changes in water depths, can affect gait patterns during aquatic treadmill walking.  相似文献   
49.
The biomechanical profile of high-level endurance runners may represent a useful model that could be used for developing training programmes designed to improve running style. This study, therefore, sought to compare the biomechanical characteristics of high-performance and recreational runners. Kinematic and kinetic measurements were taken during overground running from a cohort of 14 high-performance (8 male) and 14 recreational (8 male) runners, at four speeds ranging from 3.3 to 5.6?m?s?1. Two-way ANOVA analysis was then used to explore group and speed effects and principal component analysis used to explore the interdependence of the tested variables. The data showed the high-performance runners to have a gait style characterised by an increased vertical velocity of the centre of mass and a flight time that was 11% longer than the recreational group. The high-performance group were also observed to adopt a forefoot strike pattern, to contact the ground with their foot closer to their body and to have a larger ankle moment. Importantly, although observed group differences were mostly independent of speed, the tested variables showed a high degree of interdependence suggesting an underlying unitary phenomenon. This is the first study to compare high-performance and recreational runners across a full range of kinematic and kinetic variables. The results suggest that high-performance runners maintain stride length with a prolonged aerial phase, rather than by landing with a more extended knee. These findings motivate future intervention studies that should investigate whether recreational runners could benefit from instruction to decrease shank inclination at foot contact.  相似文献   
50.
BackgroundMethodological issues have been identified when quantifying exposure to adversity and abuse. To address a single type may obscure covarying effects. To sum multiple exposures gives equal weight to each. Latent class analysis (LCA) addresses this by identifying homogenous subpopulations. Most studies using LCA have pooled gender data in spite of evidence that the nature and frequency of exposure differs by gender. Males report more interpersonal abuse, females report more of other exposures, particularly sexual.ObjectiveThis study aimed to identify if stratifying data by gender resulted in different profiles of adversity/abuseParticipants and setting: The National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) wave II, a large community-based survey, nationally representative of the US population.MethodThis study used 14 indicators of childhood adversity as the basis for LCA.ResultsThe number and nature of classes differed by gender. The best solution for females was 4-class: a low risk class; a class at higher risk of sexual abuse; a class at higher risk of physical abuse; a class at higher risk of combined physical and sexual abuse. The best solution for males had only 3-classes; a low risk class, a class at higher risk of sexual abuse; a class at higher risk of physical abuse. The combined dataset resulted in a solution similar to the female solution.ConclusionThe importance of developing models for males and females separately was evidenced by the male and female classes being differentially associated with mental health variables.  相似文献   
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