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   1729篇
  免费   88篇
管理学   140篇
民族学   8篇
人才学   1篇
人口学   180篇
丛书文集   1篇
理论方法论   186篇
综合类   6篇
社会学   1218篇
统计学   77篇
  2023年   47篇
  2022年   7篇
  2021年   10篇
  2020年   32篇
  2019年   65篇
  2018年   66篇
  2017年   90篇
  2016年   56篇
  2015年   43篇
  2014年   82篇
  2013年   864篇
  2012年   69篇
  2011年   67篇
  2010年   36篇
  2009年   20篇
  2008年   26篇
  2007年   22篇
  2006年   27篇
  2005年   16篇
  2004年   17篇
  2003年   11篇
  2002年   10篇
  2001年   7篇
  2000年   6篇
  1999年   6篇
  1998年   2篇
  1997年   7篇
  1996年   7篇
  1995年   8篇
  1994年   13篇
  1993年   9篇
  1992年   10篇
  1991年   8篇
  1990年   6篇
  1989年   5篇
  1988年   5篇
  1987年   1篇
  1986年   6篇
  1985年   4篇
  1984年   2篇
  1983年   1篇
  1982年   1篇
  1981年   5篇
  1980年   4篇
  1979年   4篇
  1978年   2篇
  1977年   2篇
  1975年   2篇
  1971年   1篇
排序方式: 共有1817条查询结果,搜索用时 718 毫秒
11.
The Evolution of Knowledge and the Dynamics of an Industry Network   总被引:1,自引:0,他引:1  
The paper moves a step forward in the direction of establishing a connection between the structure and evolution of knowledge bases and the structure and evolution of organizational forms in innovative activities in a science-intensive industry. The paper has an explicit focus on the dynamics of the network of collaborative agreements in R&D in the pharma/biotech industry after the “molecular biology revolution”. Using a comprehensive dataset, built by the authors integrating several sources in the industry, the dynamics of the network over time is extensively analyzed. With regards to network structure, it is found that, while the size of the network increases over time due to net flows of entry, its topological properties remain relatively unchanged. The evolution of the network has occurred without relevant deformations in the core-periphery profile. With regards to age-dependent propensity to collaborate, the paper finds that the extent of inter-generational collaboration is much more significant than intra-generational collaboration. In addition, the propensity of firms of a given generation to enter into collaboration with firms of a different generation increases with the distance between the two, while the total number of intra-generational collaborations decreases over time and, moreover, tends to decrease for most recent generations. In the paper a unitary and coherent explanation of the evidence is developed, coming to reveal the existence of a striking isomorphism between structural properties of the dynamics of knowledge and of the evolution of network structure. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
12.
13.

Developing environments responsive to the aspirations of older people has become a major concern for social and public policy. Policies and programs directed at achieving “age-friendly” communities are considered to require a wide range of interventions, including actions at the level of the social and physical environment. This article compares the age-friendly approaches of two European cities, Brussels and Manchester, with a particular focus on policies and initiatives that promote active aging in an urban context. The article examines, first, the demographic, social, and multicultural contexts of Brussels and Manchester; second, the way in which both cities became members of the World Health Organization Global Network of Age-Friendly Cities and Communities; third, similarities and differences in the age-friendly approaches and actions adopted by both cities; and fourth, opportunities and barriers to the implementation of age-friendly policies. The article concludes by discussing the key elements and resources needed to develop age-friendly cities.  相似文献   
14.
People with learning difficulties are considerably more likely to experience sexual and other forms of violence than non-disabled people. Nevertheless, several respondents in this study have demonstrated some self-protective competencies. Most knew of their right not to be violated and a number of participants described situations when they had attempted to initiate their own safeguarding. Some had asked others for help with this. However, appropriate assistance was not always provided. This indicates that risk may be aggravated by social barriers. This paper focuses on highlighting the resistance skills that are prevalent amongst some people with learning difficulties. It concludes with suggestions on ways in which individuals may be further supported to realise their potential to play a more active role in directing and regaining their own protection.  相似文献   
15.
16.
Attitudes of Italian heterosexual men and women toward gay men, both HIV positive and negative, are poorly investigated. Italian culture is still extremely conservative and provides limited support to the gay community (e.g., lack of same-sex marriage recognition). Consequently, gay men experience social exclusion and disparities. The present study explores the association between homophobia and closeness with sexual orientation and HIV status. 261 heterosexual Italian men and women were assessed for feelings of closeness and homophobia after reading a vignette where the character was C1: heterosexual and HIV negative; C2: gay and HIV negative; or C3: gay and HIV positive. Experiences of homophobia and closeness varied depending on gender of participant and condition assigned, and higher levels of homophobia were correlated with lower levels of closeness regardless of HIV status. Implications and future directions are discussed.  相似文献   
17.
18.
Background: Sarcopenia is a pathophysiological condition diffused in elderly people; it represents a social issue due to the longer life expectancy and the growing aging population. It affects negatively quality of life and it represents a risk factor for other pathologies, such as diabetes, cardiovascular disease, and obesity. No silver bullet exists to hinder sarcopenia, but it may be counteracted by physical exercise, nutrition, and a proper endocrine milieu. Indeed, we aim to analyze the scientific literature to give to clinician effective advices to counteract sarcopenia.

Main text: Physical exercise, proper nutrition, optimized hormonal homeostasis represent the three pillars to fight sarcopenia. Physical exercise represents the most effective remedy to face sarcopenia, in particular if it is combined with a proper diet and with an adequate endocrine milieu. Consistency in training, adequate daily protein intake and eugonadism seems to be the keys to fight sarcopenia. The combination of these three pillars might act synergistically.

Conclusions: Optimization of these factors may increase their efficiency; however, scientific data may be sometimes confusing so far. Therefore, we aim to give practical advices to clinician to identify and to highlight the most important aspects in each of these three factors that should be addressed.  相似文献   

19.
Search algorithms are often compared by the optimization speed achieved on some sets of cost functions. Here some properties of algorithms’ optimization speed are introduced and discussed. In particular, we show that determining whether a set of cost functions F admits a search algorithm having given optimization speed is an NP-complete problem. Further, we derive an explicit formula to calculate the best achievable optimization speed when F is closed under permutation. Finally, we show that the optimization speed achieved by some well-know optimization techniques can be much worse than the best theoretical value, at least on some sets of optimization benchmarks.  相似文献   
20.
This exploratory paper deals with human–animal role identity pairings such as parent–child or sibling–sibling and the necessity of support from other actors both for the formation of these idiosyncratic identities, as well as for their situational placement in social environments not limited to the nonhuman animal. Taken from a qualitative study examining identity formation counter to the nonhuman animal, I use in‐depth interviews of both people with and without human children to demonstrate how human‐to‐human relationships are formed by categorizing the companion animal as a “child” of sorts within the family structure. These relationships prove integral to the continued development and enactment of identities such as the animal “parent” or the animal “sibling” via three different groups: their own parents, partners, and, in one case, adult siblings. This creates positive affect and commitment to the identity across other social situations. Implications of these findings for identity theory and family research are discussed.  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