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   317篇
  免费   25篇
  国内免费   1篇
耳鼻咽喉   4篇
儿科学   20篇
妇产科学   18篇
基础医学   47篇
口腔科学   6篇
临床医学   26篇
内科学   70篇
皮肤病学   8篇
神经病学   28篇
特种医学   4篇
外科学   42篇
综合类   2篇
一般理论   2篇
预防医学   12篇
眼科学   15篇
药学   23篇
中国医学   1篇
肿瘤学   15篇
  2024年   1篇
  2023年   6篇
  2022年   5篇
  2021年   14篇
  2020年   10篇
  2019年   18篇
  2018年   16篇
  2017年   14篇
  2016年   13篇
  2015年   11篇
  2014年   22篇
  2013年   19篇
  2012年   27篇
  2011年   17篇
  2010年   15篇
  2009年   14篇
  2008年   23篇
  2007年   26篇
  2006年   19篇
  2005年   18篇
  2004年   11篇
  2003年   8篇
  2002年   5篇
  2000年   2篇
  1997年   1篇
  1994年   1篇
  1991年   1篇
  1987年   1篇
  1986年   2篇
  1985年   1篇
  1977年   1篇
  1974年   1篇
排序方式: 共有343条查询结果,搜索用时 10 毫秒
1.
2.
3.
Seminal oxidative stress (OS) is a major contributing factor to male infertility. Semen analysis cannot identify reactive oxygen species (ROS), which can be measured using a chemiluminescence assay. Measurement of redox potential provides a more comprehensive assessment of OS, although the test has yet to be fully validated. This study aimed to validate the MiOXsys analyser for measuring static oxidation–reduction potential (sORP). Results demonstrated that duplicate measurements must be taken, sensors must be batch tested, and sockets should be regularly changed to avoid inconsistency in measurement. Measurement of sORP using MiOXsys exhibited good reproducibility across different operators (p = 0.469), analysers (p = 0.963) and days (p = 0.942). It is not affected by mechanical agitation (p = 0.522) or snap freezing and thawing (p = 0.823). The stability of sORP over time requires further verification, particularly in samples with high initial sORP. Measurement is temperature sensitive between 2 and 37°C, significantly increasing with increasing temperature (p = 0.0004). MiOXsys is a more stable assay for assessing OS than chemiluminescence methods and permits greater flexibility for sample handling. MiOXsys could be implemented to complement semen analysis as part of routine diagnostic testing for male infertility and may be useful in identifying contributing factors to idiopathic infertility.  相似文献   
4.
Most children with asthma have their disease easily controlled if low‐dose inhaled corticosteroids (ICSs) are regularly and correctly administered. If a child presents with asthma which is apparently resistant to therapy with high‐dose ICS and other controllers, then they have problematic severe asthma. However, in light of the UK National Review of Asthma Deaths, definitions of severe asthma based solely on the levels of prescribed treatment are too narrow. A detailed assessment of all such children should be performed. First, the diagnosis of asthma should be confirmed, then co‐morbidities assessed. Next, a nurse‐led assessment further characterizes the problem, conventionally categorizing the child as either having difficult asthma or severe therapy‐resistant asthma. Here, we reassess in particular the interactions between, and management of, these two categories, highlighting that this dichotomous classification may need reconsideration. We use bronchoscopy and an intramuscular steroid injection to determine if the child has steroid‐resistant asthma, using a novel, multidomain approach because the adult definition does not apply to around half the children we see. Finally, we highlight some mechanistic data which have emerged from this protocol such as the absence of T‐helper 2 (TH2) cytokines even in eosinophilic severe asthma and the potential role of the innate epithelial cytokine IL‐33, novel data on lineage negative innate lymphoid cells, which we can measure in induced sputum, and demonstrating that intraepithelial neutrophils are associated with better, not worse asthma outcomes. Severe paediatric asthma is very different from severe asthma in adults, and approaches must not be uncritically extrapolated from adult disease to children.  相似文献   
5.
6.
7.
8.
To investigate the role of sex steroids of the seminal fluid on sperm quality, the relationships between sex steroids and milt quality parameters (sperm motility and sperm production) were investigated in the Persian sturgeon. The seminal fluid levels of 17α,20β,21-trihydroxy-4-pregnen-3-one (20βs), and 11-ketotestosterone (11-KT) had positive relationships with sperm motility characteristics (percentage and duration of motility) and sperm density. Also, no relationships were found between other sex steroids including: Testosterone (T), progesterone (P), 17α-hydroxyprogesterone (OHP), and milt quality parameters. The good correlation of 20βs and 11-KT of the seminal fluid with sperm motility and sperm density suggests that these steroids may be important hormones involving in final maturation of the Persian sturgeon spermatozoa.  相似文献   
9.
10.
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