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   3832篇
  免费   155篇
  国内免费   23篇
管理学   290篇
民族学   14篇
人才学   5篇
人口学   84篇
丛书文集   311篇
理论方法论   329篇
综合类   1872篇
社会学   447篇
统计学   658篇
  2024年   1篇
  2023年   15篇
  2022年   26篇
  2021年   42篇
  2020年   56篇
  2019年   101篇
  2018年   91篇
  2017年   90篇
  2016年   88篇
  2015年   106篇
  2014年   189篇
  2013年   336篇
  2012年   215篇
  2011年   272篇
  2010年   164篇
  2009年   232篇
  2008年   209篇
  2007年   201篇
  2006年   188篇
  2005年   163篇
  2004年   163篇
  2003年   151篇
  2002年   155篇
  2001年   151篇
  2000年   109篇
  1999年   48篇
  1998年   33篇
  1997年   31篇
  1996年   15篇
  1995年   25篇
  1994年   28篇
  1993年   10篇
  1992年   10篇
  1991年   6篇
  1990年   8篇
  1989年   8篇
  1988年   7篇
  1987年   4篇
  1986年   5篇
  1985年   35篇
  1984年   42篇
  1983年   31篇
  1982年   34篇
  1981年   29篇
  1980年   23篇
  1979年   34篇
  1978年   24篇
  1977年   5篇
  1974年   1篇
排序方式: 共有4010条查询结果,搜索用时 15 毫秒
1.
A recent literature emphasizes that gender differences in the labor market may in part be driven by a gender gap in willingness to compete. However, whereas experiments in this literature typically investigate willingness to compete in private environments, real world competitions often have a more public nature, which introduces potential social image concerns. If such image concerns are important, and men and women differ in the degree to which they want to be seen as competitive, making tournament entry decisions publicly observable may further exacerbate the gender gap. We test this prediction using a laboratory experiment (N = 784) that varies the degree to which the decision to compete, and its outcome, is publicly observable. We find that public observability does not alter the magnitude of the gender gap in willingness to compete in an economically or statistically significant way.  相似文献   
2.
3.
ProblemDespite the introduction of preventive guidelines, no decrease in the incidence of early onset infection was observed.BackgroundEarly onset group B streptococcal (EOGBS) infection is an important cause of neonatal morbidity and mortality.AimOur study was conducted to determine adherence to three guideline-based group B streptococcus (GBS) preventive strategies.MethodsA prospective experimental study clustered by obstetric collaboration region was performed between March 2013 and August 2014 among midwives, obstetricians and paediatricians in the Netherlands. At baseline, the three regions operated according to the Dutch preventive strategy (founded on the risk-based strategy) in order to prevent EOGBS infection, whereas in the study period they followed either the risk-based, the combination or the Dutch strategy. Adherence was measured prospectively per pregnant woman, using predefined core elements of each preventive strategy: identification of risk factors, maternal GBS screening, application of intrapartum antibiotic prophylaxis and observation of the child. Data about adherence to the core elements were collected from medical records, maternal questionnaires and laboratory test results.FindingsIn the three regions, a total of 121 care providers and 1562 women participated.We found an overall adherence of 90% to the risk-based strategy, 57% to the combination strategy and 89% to the Dutch strategy. Adherence to a strategy in case women had EOGBS risk factors was below 20% in all strategies.DiscussionThe majority of women with EOGBS risk factors did not receive the care prescribed by any of three preventive strategies and were not treated optimally.ConclusionThe risk-based and the Dutch strategy are the recommended strategies for implementation.  相似文献   
4.
This paper explores the dialectic of place and community identity in Mount Pleasant, a multi–ethnic and multi–class U.S. neighborhood where definitions of place are hotly contested among its residents. In a grant proposal for public toilets, Mount Pleasant writers use linguistic strategies such as presupposition, deixis, and contrast, coupled with discursive themes of filth and geography, to construct a core of the Mount Pleasant community. The writers place themselves and people who share their values in that core, and immigrants at the margins. These strategies serve as a discursive type of spatial purification practice (cf. Sibley 1988) through which the grantwriters set up a moral and spatial order where they and other core community members are deemed to use space ‘appropriately’, and thus inhabit positive moral positions, while immigrant community members’ imputed ‘inappropriate’ use of space is used to construct negative moral positions for them.  相似文献   
5.
选择成年、健康、未孕母兔 32只 ,随机分成 8组 ,分别给予促性腺激素 (Ⅰ组 )、VD3(Ⅱ组 )、VE 亚硒酸钠 (Ⅲ组 ) ,促性腺激素 +VD3(Ⅳ组 )、VD3+VE 亚硒酸钠 (Ⅴ组 )、促性腺激素 +VE 亚硒酸钠(Ⅵ组 )、促性腺激 +VD3+VE 亚硒酸钠 (Ⅶ组 ) ,空白对照 8种处理。试验结果表明 ,母兔经药物处理后 ,其繁殖性能 (发情状况、排卵数、正常受精卵数 )都比对照组显著地提高 ,但Ⅰ、Ⅳ、Ⅵ组有畸形卵子存在 ,以处理Ⅶ组效果最好 ,其排卵数达 4 7± 2 0 .3个 ,正常受精卵 35个 ,分别比对照组多 36 .5个、30个。  相似文献   
6.
中国古代的民本思想明确提出的“民为神主”、“民为邦本”、“民贵君轻”等朴素唯物主义观点,对于我党坚持“三个代表”重要思想,坚持群众观点,坚持立党为公、执政为民,深化中国共产党与人民群众的关系,加强自身建设,丰富和发展马克思主义人民观具有重要的现实意义。  相似文献   
7.
Spatial variation in soil inorganic nitrogen across an arid urban ecosystem   总被引:4,自引:1,他引:3  
We explored variations in inorganic soil nitrogen (N) concentrations across metropolitan Phoenix, Arizona, and the surrounding desert using a probability-based synoptic survey. Data were examined using spatial statistics on the entire region, as well as for the desert and urban sites separately. Concentrations of both NO3-N and NH4-N were markedly higher and more heterogeneous amongst urban compared to desert soils. Regional variation in soil NO3-N concentration was best explained by latitude, land use history, population density, along with percent cover of impervious surfaces and lawn, whereas soil NH4-N concentrations were related to only latitude and population density. Within the urban area, patterns in both soil NO3-N and NH4-N were best predicted by elevation, population density and type of irrigation in the surrounding neighborhood. Spatial autocorrelation of soil NO3-N concentrations explained 49% of variation among desert sites but was absent between urban sites. We suggest that inorganic soil N concentrations are controlled by a number of ‘local’ or ‘neighborhood’ human-related drivers in the city, rather than factors related to an urban-rural gradient.  相似文献   
8.
在纪念中国抗日战争、世界反法西斯战争胜利60周年前夕,历史文化名城镇江第三次举行赛珍珠学术研讨会,纪念中国人民的朋友、美国女作家赛珍珠诞辰113周年.来自海内外逾百位专家学者研究和探讨了这位1938年诺贝尔文学奖得主的文学创作的题材特性、主题意蕴及艺术构成;考察和评估了她当年反映我国抗日斗争的文学作品、支持中国人民抗日的政论言论以及大量卓有成效的援华抗日活动的功绩;思考和展望了她所留给我们的遗产,在今天全球化和本土化趋势并存发展的语境下,其跨文化的独特经历及对文化多元共存、互相尊重的认识所具有的特殊价值和深远意义.  相似文献   
9.
B2C电子商务败因:创新范式研究   总被引:3,自引:0,他引:3  
B2C电子商务的发展经历了泡沫-失败-复苏的周期,深刻分析其失败的原因,对于今后B2C的发展是有指导意义的。B2C商务模式是一种创新行为,B2C的失败是一种创新行为的失败。本文采用创新理论框架对其失败的原因进行分析。  相似文献   
10.
Many recent papers have used semiparametric methods, especially the log-periodogram regression, to detect and estimate long memory in the volatility of asset returns. In these papers, the volatility is proxied by measures such as squared, log-squared, and absolute returns. While the evidence for the existence of long memory is strong using any of these measures, the actual long memory parameter estimates can be sensitive to which measure is used. In Monte-Carlo simulations, I find that if the data is conditionally leptokurtic, the log-periodogram regression estimator using squared returns has a large downward bias, which is avoided by using other volatility measures. In United States stock return data, I find that squared returns give much lower estimates of the long memory parameter than the alternative volatility measures, which is consistent with the simulation results. I conclude that researchers should avoid using the squared returns in the semiparametric estimation of long memory volatility dependencies.  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