首页 | 官方网站   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   115篇
  免费   11篇
医药卫生   126篇
  2024年   1篇
  2023年   3篇
  2022年   5篇
  2021年   17篇
  2020年   11篇
  2019年   9篇
  2018年   18篇
  2017年   8篇
  2016年   4篇
  2015年   6篇
  2014年   7篇
  2013年   9篇
  2012年   6篇
  2011年   4篇
  2010年   2篇
  2009年   2篇
  2008年   3篇
  2007年   1篇
  2006年   1篇
  2005年   1篇
  2004年   2篇
  2003年   3篇
  2002年   1篇
  2000年   1篇
  1999年   1篇
排序方式: 共有126条查询结果,搜索用时 15 毫秒
121.
Objectives:To estimate the prevalence of depression among Saudi adolescents and identify its correlates.Methods:This was a cross-sectional study using a multistage random technique that included students at the intermediate and secondary levels in Riyadh, Saudi Arabia. Patient Health Questionnaire (PHQ-9) was used as a tool, in addition to a survey of the potential risk factors. Binary logistic regression was conducted.Results:Out of 960 students, 32.4% were found to have moderate to severe depression. The age group of 16-19 years was more at risk. Female gender and low father’s education level were significant predictors of depression. Less internet use and more physical activity are considered a protective factor against depression, OR -0.531 (95% CI: 0.315-0.894) and OR -0.668 (95% CI: 0.468-0.953), respectively. Whereas the physical abuse, OR 2.047 (95% CI: 1.287-3.255) and emotional abuse, OR 2.576 (95% CI: 1.740-3.813) considered risk factors for depression.Conclusion:The prevalence of depression among Saudi adolescents is worrisome. Urgent and firm actions should be taken in response to the increasing prevalence of depression worldwide.  相似文献   
122.
<正>INTRODUCTION The past two decades have witnessed one of the most contentious scientific debates in the field of temperature management after cardiac arrest in adults.It started in 2002,following the publication of two groundbreaking trials showing lower mortality rates and improved neurologic recovery with the use of active cooling.[1,2]International recommendations advocate active cooling in the range of 32–34℃for comatose survivors of out-of-hospital cardiac arrest (OHCA).<...  相似文献   
123.
We report a new adsorbent nanocomposite material based on matrix-dispersed superparamagnetic iron oxide nanoparticles (SPIONs) in molecularly-imprinted polyaniline for the removal of chlorpyrifos (CPF), a hazardous organophosphate pesticide, from water. The synthesized magnetic molecularly-imprinted polymer (MMIP) was characterized by FTIR spectroscopy, XRD, magnetic susceptibility, DLS, zeta potential measurement, SEM and high-resolution TEM imaging. The average size of the naked SPIONs ranges from 15 to 30 nm according to the high-resolution TEM analysis. Moreover, the adsorption kinetics, thermodynamic parameters (ΔG, ΔH and ΔS), adsorption isotherms and rebinding conditions were investigated in detail. The proposed MMIP has an imprinting factor of 1.64. In addition, it showed a high experimental adsorption capacity of 1.77 mg g−1 and a removal efficiency of nearly 80%. The fabricated MMIP material demonstrated excellent magnetic susceptibility allowing for easy separation using an external magnetic field. The adsorption mechanism of CPF onto the MMIP adsorbent followed the second-order kinetics model and fitted to the Temkin adsorption isotherm. By studying the adsorption thermodynamics, negative ΔG values (−1.955 kJ mol−1 at room temperature) were obtained revealing that the adsorption process is spontaneous. Furthermore, the maximum adsorption capacity was obtained at room temperature (ca. 303 K), neutral pH and using a high CPF concentration.

An efficient magnetic molecularly-imprinted polymer adsorbent for removal of chlorpyrifos organophosphate pesticide from water is reported.  相似文献   
124.
Craniosynostosis is a birth defect occurring in approximately one in 2000 live births, where premature fusion of the cranial bones inhibits growth of the skull during critical periods of brain development. The resulting changes in skull shape can lead to compression of the brain, causing severe complications. While we have some understanding of the molecular pathology of craniosynostosis, a large proportion of cases are of unknown genetic aetiology. Based on studies in mouse, we previously proposed that the ciliopathy gene Fuz should be considered a candidate craniosynostosis gene. Here, we report a novel variant of FUZ (c.851 G > C, p.(Arg284Pro)) found in monozygotic twins presenting with craniosynostosis. To investigate whether Fuz has a direct role in regulating osteogenic fate and mineralisation, we cultured primary osteoblasts and mouse embryonic fibroblasts (MEFs) from Fuz mutant mice. Loss of Fuz resulted in increased osteoblastic mineralisation. This suggests that FUZ protein normally acts as a negative regulator of osteogenesis. We then used Fuz mutant MEFs, which lose functional primary cilia, to test whether the FUZ p.(Arg284Pro) variant could restore FUZ function during ciliogenesis. We found that expression of the FUZ p.(Arg284Pro) variant was sufficient to partially restore cilia numbers, but did not mediate a comparable response to Hedgehog pathway activation. Together, this suggests the osteogenic effects of FUZ p.(Arg284Pro) do not depend upon initiation of ciliogenesis.Subject terms: Development, Disease model, Mutation  相似文献   
125.
酵母菌药用乳糖酶制备新方法   总被引:3,自引:0,他引:3       下载免费PDF全文
目的:建立一种简易的从酵母菌制备克鲁维酵母乳糖酶的方法.方法:在30L发酵罐中进行发酵,用对羟基苯甲酸酯进行细胞破壁,用超微过滤方法浓缩破壁液.结果:乳糖酶的收率可达到每毫升发酵液含11.4 ONPG单位.从酵终细胞中释放乳糖酶可达70%,每毫升牛奶中加入1.2 ONPG单位制备的液态乳糖酶可使牛奶中的乳糖水解率达到70%.  相似文献   
126.
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-23

京公网安备 11010802026262号