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   210篇
  免费   5篇
  国内免费   1篇
安全科学   20篇
废物处理   10篇
环保管理   39篇
综合类   42篇
基础理论   37篇
污染及防治   43篇
评价与监测   16篇
社会与环境   6篇
灾害及防治   3篇
  2024年   1篇
  2023年   3篇
  2022年   5篇
  2021年   7篇
  2020年   5篇
  2019年   7篇
  2018年   7篇
  2017年   9篇
  2016年   13篇
  2015年   6篇
  2014年   14篇
  2013年   24篇
  2012年   17篇
  2011年   20篇
  2010年   13篇
  2009年   11篇
  2008年   7篇
  2007年   5篇
  2006年   7篇
  2005年   9篇
  2004年   4篇
  2003年   7篇
  2002年   2篇
  2001年   3篇
  2000年   2篇
  1999年   1篇
  1998年   3篇
  1996年   1篇
  1994年   1篇
  1993年   1篇
  1991年   1篇
排序方式: 共有216条查询结果,搜索用时 312 毫秒
101.
Upper tract dilatation presenting as renal pelvis dilatation with or without ureteric dilatation is one of the more common abnormalities detected on prenatal ultrasound scanning. The majority of cases are due to pelvi-ureteric and vesico-ureteric junction anomalies, and vesico-ureteric reflux. Prenatal diagnosis with ultrasound may be aided by biochemical analysis of fetal blood and urine. The natural history of prenatally detected abnormalities remains under review. Precise diagnosis, and therefore prognosis, may not be made until after birth. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
102.
103.
The roles of community design and parent and child perceptions of walkability to school are tested for associations with walking in three communities: a walkable new urbanist community, a mixed community (standard suburban community where the walk to school traversed part of the new urbanist community), and less walkable standard suburban community. Perceived environmental barriers to walking to school are measured and compared for fifth graders (n = 193) and their parents (n = 177). Results showed that children and parents often agreed on walking barriers, except an interaction showed that — in the less walkable community — parents perceived worse barriers than did their children. Perceptions of barriers increased from walkable, to mixed, to less walkable communities. Students walked more when they attended the school in the walkable community, they lived near school, parents and children perceived fewer barriers to walking, and children had lower BMI scores, net of demographic controls. Thus the walk to school is embedded within multiple types of supports, all of which should be addressed to encourage walking to school.  相似文献   
104.
105.
106.
107.
Plastics continues to have a critical and essential role in human society such as food packing,product packages and building materials.In the meantime,it has be...  相似文献   
108.
How do Cambodian villagers perceive sustainability and what do they do 'on the ground'? Looking at sustainability issues through the lens of two local resource management committees, and using a triangulation of social science research methods, this paper examines the roles and responsibilities of these groups and how they grapple with resource degradation and related activities. The committees have experimented with a range of resource management strategies, from creating fishing sanctuaries to resolving fishing gear theft. The results indicate that one reason villagers are willing to engage in community-based management is when they believe that they can improve livelihoods within their community. Community-based management is being carried out in the absence of formal legislation; it is recognized through government policy and administrative approvals. In this regard, local-level support and leadership has been key, and the current arrangement has created the political space for experimentation and learning.  相似文献   
109.
PurposeYoung novice drivers experience significantly greater risk of being injured or killed in car crashes than older more experienced drivers. This research utilised a qualitative approach guided by the framework of Akers’ social learning theory. It explored young novice drivers’ perspectives on risky driving including rewards and punishments expected from and administered by parents, friends, and police, imitation of parents’ and friends’ driving, and advantages and disadvantages of risky driving.MethodsTwenty-one young drivers (12 females, 9 males) aged 16–25 years (M = 17.71 years, SD = 2.15) with a Learner (n = 11) or Provisional (n = 10) driver licence participated in individual or small group interviews.Findings and conclusionsContent analysis supported four themes: (1) rewards and (2) punishments for risky driving, and the influence of (3) parents and (4) friends. The young novice drivers differed in their vulnerability to the negative influences of friends and parents, with some novices advising they were able to resist risky normative influences whilst others felt they could not. The authority of the police as enforcers of road rules was either accepted and respected or seen as being used to persecute young novices. These findings suggest that road safety interventions should consider the normative influence of parents and friends on the risky and safe behaviour of young novices. Police were also seen as influential upon behaviour. Future research should explore the complicated relationship between parents, friends, the police, young novices, and their risky driving behaviour.  相似文献   
110.
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