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   26457篇
  免费   491篇
  国内免费   15篇
管理学   3577篇
民族学   193篇
人才学   2篇
人口学   3743篇
丛书文集   172篇
理论方法论   1998篇
综合类   986篇
社会学   12923篇
统计学   3369篇
  2023年   86篇
  2021年   127篇
  2020年   261篇
  2019年   323篇
  2018年   2002篇
  2017年   2164篇
  2016年   1434篇
  2015年   374篇
  2014年   420篇
  2013年   2712篇
  2012年   868篇
  2011年   1670篇
  2010年   1472篇
  2009年   1147篇
  2008年   1303篇
  2007年   1480篇
  2006年   488篇
  2005年   656篇
  2004年   615篇
  2003年   540篇
  2002年   455篇
  2001年   422篇
  2000年   363篇
  1999年   335篇
  1998年   250篇
  1997年   220篇
  1996年   223篇
  1995年   221篇
  1994年   207篇
  1993年   207篇
  1992年   228篇
  1991年   234篇
  1990年   221篇
  1989年   196篇
  1988年   229篇
  1987年   236篇
  1986年   171篇
  1985年   192篇
  1984年   217篇
  1983年   203篇
  1982年   177篇
  1981年   155篇
  1980年   138篇
  1979年   155篇
  1978年   132篇
  1977年   107篇
  1976年   125篇
  1975年   135篇
  1974年   102篇
  1972年   77篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
901.

Background

Physical exercise (PE), virtual reality-based exercise (VRE), and brain exercise (BE) can influence physical and cognitive conditions in older persons. However, it is not known which of the three types of exercises provide the best effects on physical and cognitive status, and which exercise is preferred by older persons. This study compared the effects of PE, VRE, and BE on balance, muscle strength, cognition, and fall concern. In addition, exercise effort perception and contentment in older persons was evaluated.

Methods

Eighty-four older persons (n?=?84) were randomly selected for PE, VRE, BE, and control groups. The exercise groups received 8-week training, whereas the control group did not. Balance was assessed by Berg Balance Scale (BBS) and Timed Up and Go test (TUG), muscle strength by 5 Times Sit to Stand (5TSTS) and left and right hand grip strength (HGS), cognition by Montreal Cognitive Assessment (MoCA) and Timed Up and Go test Cognition (TUG-cog), fall concern by Fall Efficacy Scale International (FES-I), exercise effort perception by Borg category ratio scale (Borg CR-10), and exercise contentment by a questionnaire.

Results

After exercise, PE significantly enhanced TUG and 5TSTS to a greater extent than VRE (TUG; p?=?0.004, 5TSTS; p?=?0.027) and BE (TUG; p?=?0,012, 5TSTS; p?<?0.001). VRE significantly improved MoCA (p?<?0.001) and FES-I (p?=?0.036) compared to PE, and 5TSTS (p?<?0.001) and FES-I (p?=?0.011) were improved relative to BE. MoCA was significantly enhanced by BE compared to PE (p?<?0.001) and both MoCA and TUG-cog were improved compared to VRE (p?=?0.04). PE and VRE significantly (p < 0.001) increased Borg CR-10 in all exercise sessions, whereas BE showed a significant improvement (p?< 0.001) in the first 4 sessions. Participants had a significantly greater satisfaction with BE than controls (p?=?0.006), and enjoyed VRE and BE more than PE (p?< 0.001). Subjects in all exercise groups exhibited benefits compared to the control group (p?< 0.001).

Conclusions

PE provided the best results in physical tests, VRE produced measurable improvements in physical and cognition scores, while BE enhanced cognition ability in older persons. Older persons preferred VRE and BE compared to PE. Both exercises are suggested to older persons to improve physical and cognitive conditions.
  相似文献   
902.

Background

Previous physical activity (PA) tracking studies have examined the stability of overall PA and/or PA types, but few have investigated how specific types of sport/exercise track over the life course. The aim of this study was to determine how specific sports/exercises in midlife track and predict future sport/exercise and PA in men transitioning to old age.

Methods

Seven thousand seven hundred thirty-five men (aged 40–59?years) recruited in 1978–80 were followed up after 12, 16 and 20?years. At each wave men self-reported participation in sport/exercise. Frequent sport/exercise participants (>?1/month) reported the types of sport/exercise they engaged in. Men also reported total PA, health status, lifestyle behaviours and socio-demographic characteristics. Stability of each sport/exercise was assessed using kappa statistics and intraclass correlation coefficients. Logistic regression estimated the odds of participating in sport/exercise and being active at 20-year follow up according to specific types of sport/exercise in midlife.

Results

Three thousand three hundred eighty-four men with complete data at all waves were included in analyses. Tracking of specific sports/exercises ranged from fair to substantial, with golf being the most common and most stable. Bowls was the most frequently adopted. Odds of participating in sport/exercise and being active in old age varied according to sport/exercise types in midlife. Golf and bowls in midlife were the strongest predictors of sport/exercise participation in old age. Golf, cricket and running/jogging in midlife were among the strongest predictors of being active in old age. Compared to participating in just one sport/exercise in midlife, sampling multiple sports/exercises was more strongly associated with sport/exercise participation and being active in old age.

Conclusion

The stability of sport/exercise participation from midlife to old age varies by type. Specific sports/exercises in midlife may be more likely to predict future PA than others. However, participating in a range of sports/exercises may be optimal for preserving PA into old age.
  相似文献   
903.

Background

The increasing prevalence of obesity in sub-Saharan African women is not well understood, and black South African women in the region are particularly vulnerable. This study aimed to examine whether the relationship of socioeconomic status (SES) with changes in body mass index (BMI) and waist circumference (WC) is mediated by physical activity in ageing African women.

Methods

In a longitudinal analysis of the 518 caregivers associated with the Birth to Twenty Plus study, the role of SES associated with 10-year changes in BMI and WC was tested using structural equation modelling (SEM). The degree of mediation of moderate-vigorous physical activity (MVPA) and sitting time in this association was also assessed.

Results

The prevalence of obesity increased significantly from baseline to follow-up (p?<?0.0001). In the SEM models, baseline SES had a direct positive effect on changes in BMI (β, 95% CI, 0.02 (0.005 to 0.04), and a direct negative effect on changes in MVPA (β, 95% CI, ??3.81 (??6.92 to ??0.70). Baseline MVPA had a direct negative effect (β, 95% CI, ??0.002 (??0.003 to ??0.0003) and indirect positive effect via change in MVPA (β, 95% CI, 0.01 (0.0001 to 0.001) on change in WC.

Conclusions

Our study demonstrates the role and interaction of sociodemographic and behavioural predictors of obesity, and suggests a multifaceted approach to management of the crisis in communities of ageing urban African women.
  相似文献   
904.

Background

Since age-related muscle strength loss cannot be explained solely by muscle atrophy, other determinants would also contribute to muscle strength in elderly. The present study aimed to clarify contribution of neuromuscular activation pattern to muscle strength in elderly group. From 88 elderlies (age: 61~?83 years), multi-channel surface electromyography (EMG) of the vastus lateralis muscle was recorded with two-dimensional 64 electrodes during isometric submaximal ramp-up knee extension to assess neuromuscular activation pattern. Correlation analysis and stepwise regression analysis were performed between muscle strength and the parameters for signal amplitude and spatial distribution pattern, i.e., root mean square (RMS), correlation coefficient, and modified entropy of multi-channel surface EMG.

Results

There was a significant correlation between muscle strength and RMS (r =?0.361, p =?0.001) in the elderly. Muscle thickness (r =?0.519, p <?0.001), RMS (r =?0.288, p?=?0.001), and normalized RMS (r =?0.177, p =?0.047) were selected as major determinants of muscle strength in stepwise regression analysis (r?=?0.664 in the selected model).

Conclusion

These results suggest that inter-individual difference in muscle strength in elderly can be partly explained by surface EMG amplitude. We concluded that neuromuscular activation pattern is also major determinants of muscle strength on elderly in addition to indicator of muscle volume.
  相似文献   
905.
Journals may set themselves one or several of a range of missions, but often a national Sociology Association’s journal is concerned to be a vehicle assisting in the shaping of that country’s ‘national sociology’, while maintaining some openness to international sociology. This personalised case study of New Zealand’s sociology journal discusses the extent to which this mission has been achieved over the last decade and more generally over the journal’s history, and the nitty-gritty of challenges and operational issues involved in carrying this out.  相似文献   
906.
In the present work, we investigated the pop cultural idea that people have a sixth sense, called “gaydar,” to detect who is gay. We propose that “gaydar” is an alternate label for using stereotypes to infer orientation (e.g., inferring that fashionable men are gay). Another account, however, argues that people possess a facial perception process that enables them to identify sexual orientation from facial structure. We report five experiments testing these accounts. Participants made gay-or-straight judgments about fictional targets that were constructed using experimentally manipulated stereotypic cues and real gay/straight people's face cues. These studies revealed that orientation is not visible from the face—purportedly “face-based” gaydar arises from a third-variable confound. People do, however, readily infer orientation from stereotypic attributes (e.g., fashion, career). Furthermore, the folk concept of gaydar serves as a legitimizing myth: Compared to a control group, people stereotyped more often when led to believe in gaydar, whereas people stereotyped less when told gaydar is an alternate label for stereotyping. Discussion focuses on the implications of the gaydar myth and why, contrary to some prior claims, stereotyping is highly unlikely to result in accurate judgments about orientation.  相似文献   
907.
908.
Camperio Ciani et al. argued that the Urak-Lawoi people of Ko Lipe island live in a “traditional,” “subsistence primitive society” reminiscent of the “ancestral” human past and that their socio-cultural situation is “remarkably similar” to Samoa. On this basis, they asserted that the Ko Lipe Urak-Lawoi are an appropriate population for determining the role that kin selection played in the evolution of male androphilia. The purpose of this commentary is to outline some of our concerns with this characterization and with the statistical analyses conducted by Camperio Ciani et al. in their study of the Urak-Lawoi.  相似文献   
909.
910.
This ethnographic study examines the importance of context in the emotional labor of restaurant servers. While the emotional labor of workers in the service industry has been studied extensively, little attention has been paid to the differing audiences and demands of restaurant servers in the front‐ and backstages and the ways these spaces and performances are racialized and classed. Relying on organizational materials, face‐to‐face interviews, and participant observation conducted from September through December 2013, this article addresses this gap. Findings indicate that the emotional labor that servers engage in the frontstage is processed in backstage spaces where servers interact out of earshot of customers. In this space, servers mitigate the stress associated with the emotional labor demands from the frontstage by relying on racialized and classed discourse about their customers, processes that may, in turn, contribute to the reproduction of social hierarchies.  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