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   1730篇
  免费   93篇
管理学   153篇
民族学   24篇
人口学   200篇
丛书文集   5篇
理论方法论   161篇
综合类   24篇
社会学   1003篇
统计学   253篇
  2023年   11篇
  2022年   14篇
  2021年   22篇
  2020年   71篇
  2019年   75篇
  2018年   90篇
  2017年   112篇
  2016年   90篇
  2015年   47篇
  2014年   55篇
  2013年   325篇
  2012年   106篇
  2011年   70篇
  2010年   60篇
  2009年   47篇
  2008年   50篇
  2007年   46篇
  2006年   43篇
  2005年   43篇
  2004年   44篇
  2003年   43篇
  2002年   38篇
  2001年   23篇
  2000年   28篇
  1999年   33篇
  1998年   11篇
  1997年   17篇
  1996年   13篇
  1995年   16篇
  1994年   12篇
  1993年   27篇
  1992年   18篇
  1991年   16篇
  1990年   8篇
  1989年   7篇
  1988年   8篇
  1987年   10篇
  1986年   4篇
  1985年   8篇
  1984年   8篇
  1983年   7篇
  1982年   11篇
  1981年   9篇
  1980年   5篇
  1979年   3篇
  1978年   3篇
  1977年   5篇
  1976年   5篇
  1974年   1篇
  1968年   4篇
排序方式: 共有1823条查询结果,搜索用时 531 毫秒
71.
Urbanization has been considered as a major threat to biodiversity, making its ecology of increasing interest. Many urban ecology studies have been developed in a short time-scale, measuring real-time patterns. However, long-term studies are imperative to understand the responses of some species to the urbanization process. In this study, we aimed to assess the information provided by a recent one-year citywide bird survey when compared to a published ‘historical’ bird list of a neotropical city (Xalapa, Mexico) that compiles information of the past three decades, mainly from urban greenspaces. Specifically, we contrasted species richness values and assessed differences in species composition between both lists. We recorded 51 species in the one-year citywide survey, representing ~15 % of those reported in the historical list. Nonetheless, the upper-bound confidence interval of the citywide survey richness prediction represented ~66 %. Most of the species recorded in the one-year citywide survey are insectivores and granivores, a pattern that agrees with previous findings that underline the importance of insectivores as part of urban bird communities in the Neotropics. Although we used robust methods to compare our one-year citywide bird list and the historical list for the city of Xalapa, we acknowledge the limitations of comparing them. However, our results shed some light on the kind and type of information that one-year citywide surveys can provide and the importance of long-term studies for comprehending the processes involved in biodiversity changes within urban areas over time. Undoubtedly, establishing long-term citywide surveys sampling birds and other biodiversity groups will allow us to better understand the response of biodiversity to urbanization over time.  相似文献   
72.
73.
We examined how perceived acculturation expectations from parents and school, and ethnic discrimination predicted early adolescents’ heritage and mainstream acculturation orientations at home (private domain) and in school (public domain) one year later. We surveyed 263 early adolescents of immigrant background in Germany (Mage = 10.44 years, 60% female). Multigroup path analyses revealed that perceived acculturation expectations and ethnic discrimination were more strongly related to adolescents’ private than public acculturation orientations. Parental heritage expectations were the strongest predictor of adolescents’ acculturation orientations. Boys were more susceptible than girls to ethnic discrimination and acculturation expectations in school, which affected their private and public acculturation orientations. Results highlight the importance of integrating domain‐specific and gendered experiences when analyzing adolescents’ acculturative development.  相似文献   
74.
Population and Environment - We investigate the extent to which droughts impact migration responses of rural households in Thailand and Vietnam, as well as the role of underlying mechanisms such as...  相似文献   
75.
76.
Quality-of-life studies have a 50-year history and inherited the tradition of the “social indicators” movement, born in the United States during the sixties and involving scholars and researchers, supported by the public administration and interested in gathering and analysing data aimed at studying non-economic components of societal wellbeing. The idea of quantifying “symptoms” (indicators) of living conditions has been launched by Italian statistician and criminologist, Alfredo Niceforo, who has been recognised as the pioneer of social-indicators concept. Moreover, with his book on Les indices numérique de la civilisation et du progrès, he may be considered the originator of an approach of comprehensive welfare and quality of life measurement as it is the concern of modern social indicators and quality of life.  相似文献   
77.
78.

Background

There is no current validated clinical assessment tool to measure the attainment of midwifery student competence in the midwifery practice setting. The lack of a valid assessment tool has led to a proliferation of tools and inconsistency in assessment of, and feedback on student learning.

Objective

This research aimed to develop and validate a tool to assess competence of midwifery students in practice-based settings.

Design

A mixed-methods approach was used and the study implemented in two phases. Phase one involved the development of the AMSAT tool with qualitative feedback from midwifery academics, midwife assessors of students, and midwifery students. In phase two the newly developed AMSAT tool was piloted across a range of midwifery practice settings and ANOVA was used to compare scores across year levels, with feedback being obtained from assessors.

Findings

Analysis of 150 AMSAT forms indicate the AMSAT as: reliable (Cronbach alpha greater than 0.9); valid—data extraction loaded predominantly onto one factor; and sensitivity scores indicating level of proficiency increased across the three years. Feedback evaluation forms (n = 83) suggest acceptance of this tool for the purpose of both assessing and providing feedback on midwifery student’s practice performance and competence.

Conclusion

The AMSAT is a valid, reliable and acceptable midwifery assessment tool enables consistent assessment of midwifery student competence. This assists benchmarking across midwifery education programs.  相似文献   
79.

Background

The rates of breastfeeding worldwide are slowly improving since 1996. Europe is still trailing behind the global breastfeeding incidence and prevalence rates. Thus, breastfeeding promotion, protection, prolongation and support have become an important challenge as breastfeeding sharply decreases in the first six months of life.

Objectives

The aim of this project is to determine, assess and identify the real impact of breastfeeding support networks in Murcia (Spain).

Methods

After searching unsuccessfully for a validated questionnaire, a specific one was developed and validated for measuring the impact of formal and informal support networks through five dimensions: satisfaction, consultation, experience, problems and support. The questionnaire was provided to 500 mothers with experience in breastfeeding, who brought their children to baby paediatricians between 2 June and 27 November 2014. Upon completion of the survey and fieldwork, a detailed statistical analysis was conducted.

Results

The degree of satisfaction perceived by the users of the services of support breastfeeding networks is remarkable. In addition, mothers who clarified their doubts and discussed their problems with health professionals and/or breastfeeding support networks were more likely to breastfeed for a longer duration compared to those who did not (p = 0.005). Furthermore, mothers who sought support in breastfeeding are more likely to breastfeed for more than 6 months (p < 0.0005).

Conclusion

Based on this information, we conclude that breastfeeding support networks have a positive influence in the duration of a women’s decision to breastfeed.  相似文献   
80.
This article investigates the determinants of wage gaps between European Union countries along the wage distribution, applying the methodology proposed by Firpo, Fortin and Lemieux (2009) and Fortin, Lemieux and Firpo (2011). The authors conclude that both wage structure and composition effects contribute to explaining wage differentials, but that the wage structure effect is more important. This latter effect would appear to derive from differences between unknown factors, while the composition effect can largely be explained by differences in the following areas: education, proportion of workers with supervisory responsibilities, occupational structure, and, to a lesser extent, industrial structure.  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