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   157篇
  免费   4篇
管理学   24篇
民族学   2篇
人口学   3篇
丛书文集   1篇
理论方法论   7篇
社会学   88篇
统计学   36篇
  2023年   4篇
  2022年   2篇
  2021年   3篇
  2020年   5篇
  2019年   8篇
  2018年   5篇
  2017年   9篇
  2016年   8篇
  2015年   1篇
  2014年   3篇
  2013年   15篇
  2012年   63篇
  2011年   3篇
  2010年   6篇
  2009年   2篇
  2008年   6篇
  2007年   5篇
  2006年   2篇
  2004年   1篇
  2003年   1篇
  2001年   4篇
  1995年   1篇
  1992年   1篇
  1991年   1篇
  1987年   2篇
排序方式: 共有161条查询结果,搜索用时 15 毫秒
1.
Urban Ecosystems - The development of urban areas imposes challenges that wildlife must adapt to in order to persist in these new habitats. One of the greatest changes brought by urbanization has...  相似文献   
2.
This article explores children’s perspectives regarding migration and family separation on both sides of the Mexico‐U.S. border. ‘Transnational care constellations’1 that connect separated siblings allow children to imagine the other side of the border and to explore their thoughts and perspectives through the lenses of inequality, as well as through a sense of belonging and family. This article presents ethnographic data of families that capture the dynamism of families that are both ‘here and there’ as children assemble their ideas and narratives of how transnational lives exist.  相似文献   
3.
4.
We developed a stochastic model for quantitative risk assessment for the Schistosoma mansoni (SM) parasite, which causes an endemic disease of public concern. The model provides answers in a useful format for public health decisions, uses data and expert opinion, and can be applied to any landscape where the snail Biomphalaria glabrata is the main intermediate host (South and Central America, the Caribbean, and Africa). It incorporates several realistic and case‐specific features: stage‐structured parasite populations, periodic praziquantel (PZQ) drug treatment for humans, density dependence, extreme events (prolonged rainfall), site‐specific sanitation quality, environmental stochasticity, monthly rainfall variation, uncertainty in parameters, and spatial dynamics. We parameterize the model through a real‐world application in the district of Porto de Galinhas (PG), one of the main touristic destinations in Brazil, where previous studies identified four parasite populations within the metapopulation. The results provide a good approximation of the dynamics of the system and are in agreement with our field observations, i.e., the lack of basic infrastructure (sanitation level and health programs) makes PG a suitable habitat for the persistence and growth of a parasite metapopulation. We quantify the risk of SM metapopulation explosion and quasi‐extinction and the time to metapopulation explosion and quasi‐extinction. We evaluate the sensitivity of the results under varying scenarios of future periodic PZQ treatment (based on the Brazilian Ministry of Health's plan) and sanitation quality. We conclude that the plan might be useful to slow SM metapopulation growth but not to control it. Additional investments in better sanitation are necessary.  相似文献   
5.
6.
In this study, the components of extra-Poisson variability are estimated assuming random effect models under a Bayesian approach. A standard existing methodology to estimate extra-Poisson variability assumes a negative binomial distribution. The obtained results show that using the proposed random effect model it is possible to get more accurate estimates for the extra-Poisson variability components when compared to the use of a negative binomial distribution where it is possible to estimate only one component of extra-Poisson variability. Some illustrative examples are introduced considering real data sets.  相似文献   
7.
Nearly 5.1 million children younger than age 18 live with at least one undocumented parent, about 7% of the U.S. child population. Between 2010 and 2013, an estimated 300,000 parents of U.S. citizen children were deported. Raising children in the context of deportation risk increases overall parenting stress for undocumented Latino parents. To investigate this and understand the experience of undocumented parenting, the authors interviewed 70 undocumented parents in two Southwest cities from 2012 to 2013. The authors frame their analysis using the lens of the problem of “illegality.” There are three domains of stressors associated with parenting in the context of deportation risk: trapped parenting, threat of family separation, and altered family processes. The authors discuss these findings in the context of the literature on undocumented families and parenting stress and connect these findings to the current sociopolitical context experienced by Latino families in the United States .  相似文献   
8.
Crime or disease surveillance commonly rely in space-time clustering methods to identify emerging patterns. The goal is to detect spatial-temporal clusters as soon as possible after its occurrence and to control the rate of false alarms. With this in mind, a spatio-temporal multiple cluster detection method was developed as an extension of a previous proposal based on a spatial version of the Shiryaev–Roberts statistic. Besides the capability of multiple cluster detection, the method have less input parameter than the previous proposal making its use more intuitive to practitioners. To evaluate the new methodology a simulation study is performed in several scenarios and enlighten many advantages of the proposed method. Finally, we present a case study to a crime data-set in Belo Horizonte, Brazil.  相似文献   
9.

Background

Ice-pack is widely used for alleviating postpartum perineal pain sustained after birth related perineal trauma. However, it lacks robust evidence on timing and frequency of applications, to ensure the effective and safe use of this therapy.

Aims

To evaluate if a 10 min ice-pack application relieved postpartum perineal pain and if the analgesic effect was maintained for up to 2 h.

Methods

A randomised controlled trial conducted from December 2012 to February 2013 with 69 primiparous women ≥18 years old, 6–24 h postpartum, with perineal pain ≥3, who had not received anti-inflammatory medication or analgesics after childbirth, who were randomised to a single ice-pack application on the perineum for 10 min or standard care. The primary and secondary outcomes were a reduction ≥30% in perineal pain intensity, immediately after the application and the maintenance of the analgesic effect for up to 2 h, respectively.

Findings

Immediately post-intervention, the proportion of women whose perineal pain decreased ≥30% was significantly higher in the experimental group. Within 2 h, there was no significant difference in the pain levels in both groups. Within 2 h, for 61.9% and 89.3% of women in the experimental and control group, respectively, the perineal pain levels remained unchanged. For the remaining participants, perineal pain was increasing after an average time of 1 h 45 min and 1 h 56 min for the experimental and control groups, respectively.

Conclusion

By applying an ice-pack for 10 min to the perineum, effective pain relief is achieved, that is maintained for between 1 h 45 min and 2 h.  相似文献   
10.
Introduction: Metabolic syndrome (MetS) is a constellation of interrelated risk factors of metabolic origin. Some studies suggest a possible link between low total testosterone (TT) levels and the presence of MetS.

Aim: To analyze the strength and independence of associations between TT and MetS components in non-diabetic men.

Methods: In this cross-sectional study, 143 non-diabetic men older than 40 were analyzed.

Main outcomes measure: Blood samples were collected to evaluate metabolic profile and TT levels. MetS was defined as the presence of three or more of the following characteristics: fasting blood glucose levels?≥?100?mg/dL, triglyceride?≥?150?mg/dL, HDL-c??102?cm.

Results: Mean age of the study population was 61.5?±?8.61 years old. MetS was present in 47.9% of the individuals. Thirty-four men had low TT and MetS was observed in 23 (70%) against 50 (46%) in those with normal TT (≥?300?ng/dL) (OR 4.94, p?p?=?0.03) and HDL-c (Beta: 0.19; p?=?0.04) remained significantly correlated with TT levels.

Conclusions: Low TT levels were associated with MetS diagnosis. Abdominal obesity was the MetS component independently correlated to low TT levels.  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