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   6476篇
  免费   823篇
  国内免费   74篇
耳鼻咽喉   27篇
儿科学   169篇
妇产科学   92篇
基础医学   823篇
口腔科学   163篇
临床医学   698篇
内科学   1512篇
皮肤病学   70篇
神经病学   458篇
特种医学   586篇
外科学   939篇
综合类   140篇
一般理论   2篇
预防医学   688篇
眼科学   66篇
药学   540篇
中国医学   2篇
肿瘤学   398篇
  2021年   80篇
  2020年   46篇
  2019年   76篇
  2018年   99篇
  2017年   85篇
  2016年   104篇
  2015年   100篇
  2014年   141篇
  2013年   193篇
  2012年   256篇
  2011年   298篇
  2010年   193篇
  2009年   181篇
  2008年   232篇
  2007年   298篇
  2006年   289篇
  2005年   256篇
  2004年   258篇
  2003年   230篇
  2002年   246篇
  2001年   200篇
  2000年   223篇
  1999年   181篇
  1998年   136篇
  1997年   118篇
  1996年   121篇
  1995年   124篇
  1994年   93篇
  1993年   102篇
  1992年   126篇
  1991年   127篇
  1990年   122篇
  1989年   159篇
  1988年   130篇
  1987年   154篇
  1986年   130篇
  1985年   125篇
  1984年   120篇
  1983年   105篇
  1982年   75篇
  1981年   84篇
  1980年   65篇
  1979年   77篇
  1978年   49篇
  1977年   62篇
  1974年   53篇
  1972年   62篇
  1970年   53篇
  1969年   45篇
  1968年   44篇
排序方式: 共有7373条查询结果,搜索用时 15 毫秒
1.

Objective

Arteriovenous fistulas created in patients with chronic kidney disease often lose patency and fail to become usable. This prospective trial evaluated the efficacy of vonapanitase, a recombinant human elastase, in promoting radiocephalic fistula patency and use for hemodialysis.

Methods

PATENCY-1 was a double-blind, placebo-controlled trial that enrolled 349 patients on or approaching hemodialysis and being evaluated for radiocephalic arteriovenous fistula creation. Of these, 313 were randomized and 311 treated. Patients were assigned to vonapanitase (n = 210) or placebo (n = 103). The study drug solution was applied topically to the artery and vein for 10 minutes immediately after fistula creation. The primary and secondary end points were primary patency (time to first thrombosis or corrective procedure) and secondary patency (time to abandonment). Tertiary end points included use of the fistula for hemodialysis, fistula maturation by ultrasound, and procedure rates.

Results

The Kaplan-Meier estimates of 12-month primary patency were 42% (95% confidence interval [CI], 35-49) and 31% (95% CI, 21-42) for vonapanitase and placebo (P = .25). The Kaplan-Meier estimates of 12-month secondary patency were 74% (95% CI, 68-80) and 61% (95% CI, 51-71) for vonapanitase and placebo (P = .048). The proportions of vonapanitase and placebo patients were 39% and 25% (P = .035) with unassisted use for hemodialysis and 64% and 44% (P = .006) with unassisted plus assisted use.

Conclusions

Vonapanitase treatment did not significantly improve primary patency but was associated with increased secondary patency and use for hemodialysis. Further research is needed to evaluate these end points.  相似文献   
2.
3.
Social media has become a major platform for debates on science and health. This commentary argues that while social media can present challenges to communicating important health matters, it can also provide health experts a unique opportunity to engage with and build trust among members of the public.  相似文献   
4.
5.
6.
Prevention Science - The LINKS curriculum, adapted from Britt et al. (2018a), was designed to improve unit climate, knowledge, and attitudes about mental health treatment seeking in military...  相似文献   
7.
8.
Fundamental challenges of targeting specific brain regions for treatment using pharmacotherapeutic nanoparticle (NP) carriers include circumventing the blood–brain-barrier (BBB) and tracking delivery. Angiopep-2 (AP2) has been shown to facilitate the transport of large macromolecules and synthetic nanoparticles across the BBB. Thus, conjugation of AP2 to an MS2 bacteriophage based NP should also permit transport across the BBB. We have fabricated and tested a novel MS2 capsid-based NP conjugated to the ligand AP2. The reaction efficiency was determined to be over 70%, with up to two angiopep-2 conjugated per MS2 capsid protein. When linked with a porphyrin ring, manganese (Mn2+) remained stable within MS2 and was MRI detectable. Nanoparticles were introduced intracerebroventricularly or systemically. Systemic delivery yielded dose dependent, non-toxic accumulation of NPs in the midbrain. Design of a multifunctional MRI compatible NP platform provides a significant step forward for the diagnosis and treatment of intractable brain conditions, such as tinnitus.  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