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   5574篇
  免费   395篇
  国内免费   1篇
教育   4935篇
科学研究   146篇
各国文化   122篇
体育   236篇
综合类   2篇
文化理论   25篇
信息传播   504篇
  2022年   22篇
  2021年   72篇
  2020年   103篇
  2019年   186篇
  2018年   212篇
  2017年   257篇
  2016年   207篇
  2015年   210篇
  2014年   233篇
  2013年   1496篇
  2012年   195篇
  2011年   210篇
  2010年   206篇
  2009年   174篇
  2008年   210篇
  2007年   163篇
  2006年   131篇
  2005年   121篇
  2004年   122篇
  2003年   69篇
  2002年   70篇
  2001年   65篇
  2000年   82篇
  1999年   87篇
  1998年   45篇
  1997年   52篇
  1996年   58篇
  1995年   61篇
  1994年   59篇
  1993年   56篇
  1992年   46篇
  1991年   50篇
  1990年   58篇
  1989年   36篇
  1988年   31篇
  1987年   33篇
  1986年   30篇
  1985年   38篇
  1984年   32篇
  1983年   38篇
  1982年   28篇
  1981年   25篇
  1980年   22篇
  1979年   17篇
  1978年   28篇
  1976年   16篇
  1975年   12篇
  1974年   19篇
  1973年   13篇
  1972年   13篇
排序方式: 共有5970条查询结果,搜索用时 15 毫秒
51.
52.
53.
Background:Osteoarthritis is one of the leading causes of pain and disability worldwide,and a large percentage of patients with osteoarthritis are individuals who are also obese.In recent years,a series of animal models have demonstrated that obesity-inducing diets can result in synovial joint damage(both with and without the superimposition of trauma),which may be related to changes in percentage of body fat and a series of low-level systemic inflammatory mediators.Of note,there is a disparity between whether the dietary challenges commence at weaning,representing a weanling onset,or at skeletal maturity,representing an adult onset of obesity.We wished to evaluate the effect ofthe dietary exposure time and the age at which animals are exposed to a high-fat and high-sucrose(HFS) diet to determine whether these factors may result in disparate outcomes,as there is evidence suggesting that these factors result in differential metabolic disturbances.Based on dietary exposure time,we hypothesized that rats fed an HFS diet for 14 weeks from weaning(HFS Weanling) would demonstrate an increase in knee joint damage scores,whereas rats exposed to the HFS diet for 4 weeks,starting at 12 weeks of age(HFS Adult) and rats exposed to a standard chow diet(Chow)would not display an increase in knee joint damage scores.Methods:Male Sprague-Dawley rats were fed either an HFS diet for 14 weeks from weaning(HFS Weanling) or an HFS diet for 4 weeks,starting at 12 weeks of age(HFS Adult).At sacrifice,joints were scored using the modified Mankin Criteria,and serum was analyzed for a defined subset of inflammatory markers(Interleukin-6,leptin,monocyte chemoattractant protein-1,and tumor necrosis factorα).Results:When the HFS Weanling and HFS Adult groups were compared,both groups had a similar percent of body fat,although the HFS Weanling group had a significantly greater body mass than the HFS Adult group.The HFS Weanling and HFS Adult animals had a significant increase in body mass and percentage of body fat when compared to the Chow group.Although knee joint damage scores were low in all 3 groups,we found,contrary to our hypothesis,that the HFS Adult group had statistically significant greater knee joint damage scores than the Chow and HFS Weanling groups.Furthermore,we observed that the HFS Weanling group did not have significant differences in knee joint damage scores relative to the Chow group.Conclusion:These findings indicate that the HFS Weanling animals were better able to cope with the dietary challenge of an HFS diet than the HFS Adult group.Interestingly,when assessing various serum proinflammatory markers,no significant differences were detected between the HTS Adult and HFS Weanling groups.Although details regarding the mechanisms underlying an increase in knee joint damage scores in the HFS Adult group remain to be elucidated,these findings indicate that dietary exposure time maybe less important than the age at which an HFS diet is introduced.Moreover,increases in serum proinflammatory mediators do not appear to be directly linked to knee joint damage scores in the HFS Weanling group animals but may be partially responsible for the observed knee joint damage in the adults over the very short time of exposure to the HFS diet.  相似文献   
54.
55.
56.
57.
Previous research has highlighted the positive effect that different warm-up protocols have on golf performance (e.g. Sorbie et al., 2016; Tilley & Macfarlane, 2012) with the design of warm-ups and programmes targeting and improving golf performance through the activation and development of specific muscle groups. This study aimed to examine the acute effects of two warm-up protocols on golf drive performance in comparison to a control condition. Using a randomised counterbalanced design over three testing sessions, twenty-three highly skilled golfers completed the control, dynamic and resistance-band warm-up conditions. Following each condition, a GC2 launch monitor was used to record ball velocity and other launch parameters of ten shots hit with the participants’ own driver. A repeated-measures ANOVA found significant increases in ball velocity (ηp2 = .217) between the control and both the dynamic and resistance-band warm-up conditions but no difference between these latter two, and a reduction in launch angle between control and dynamic conditions. The use of either a dynamic stretching or resistance-band warm-up can have acute benefits on ball velocity but golfers should liaise with a PGA Professional golf coach to effectively integrate this into their golf driving performance.  相似文献   
58.
It is generally acknowledged that expatriate British players and coaches were instrumental in soccer’s radiant global diffusion and that different technical and tactical emphases developed according to particular geographical locations and cultural milieu. As the twentieth century unfolded, the trend reversed with increased inward flows of elite foreign playing and coaching labour challenging the distinctive and erstwhile dominant occupational culture of the English game. This paper explores the dynamics and tensions of subcultural modification and adaptation at the British: migrant coaching talent interface. Owing to issues associated with access, the occupational subculture of elite-level football is impenetrable to most researchers. Previous employment in professional soccer allowed this author to overcome such impediments, permitting access to a range of high-status national and international players and coaches (n = 25) affecting and affected by occupational subcultural change. This enabled a distinctive research platform combining insider knowledge and grounded experience with academic orthodoxy. The paper is built upon primary data collected in semi-structured interviews and critical analysis of emerging themes. In doing so, it offers a fresh dimension to understanding the impact of globalization on elite professional English soccer. Key findings indicated the opinion of British coaches on the impact of this foreign influx polarized. Although many demonstrated an enlightened standpoint, adopting innovative practices introduced by overseas coaching talent, these views were counter-balanced by evidence of a myopic arrogance bordering on xenophobic resistance to change in what now has to be considered the global rather than the ‘English’ game.  相似文献   
59.
60.
This brief viewpoint piece depicts educational (dis)engagements apparent in researching and (re)designing higher education in and through Accessions. Accessions, a collaborative research-design project, probed at how cultures, climates and conditions of higher education may be reproducing or reshaping social inequalities and divisions. Here, questions are asked about how these might be challenged within and potentially beyond the specific locale of one university campus. This research-design project hopes to enable a critical perspective on issues of ‘participation’, ‘impact’, ‘engagement’ and ‘internationalisation’, where regulations and measures may be resisted and disrupted.  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