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   1703578篇
  免费   128112篇
  国内免费   3789篇
耳鼻咽喉   21837篇
儿科学   56156篇
妇产科学   46703篇
基础医学   242918篇
口腔科学   49109篇
临床医学   152551篇
内科学   335188篇
皮肤病学   38838篇
神经病学   132251篇
特种医学   64382篇
外国民族医学   242篇
外科学   258729篇
综合类   39170篇
现状与发展   4篇
一般理论   561篇
预防医学   125524篇
眼科学   40343篇
药学   124785篇
  7篇
中国医学   4485篇
肿瘤学   101696篇
  2021年   12708篇
  2019年   13768篇
  2018年   20224篇
  2017年   15425篇
  2016年   16834篇
  2015年   19195篇
  2014年   26574篇
  2013年   38418篇
  2012年   53440篇
  2011年   56174篇
  2010年   33147篇
  2009年   31045篇
  2008年   52138篇
  2007年   55530篇
  2006年   55930篇
  2005年   53214篇
  2004年   51419篇
  2003年   48778篇
  2002年   46959篇
  2001年   92236篇
  2000年   94073篇
  1999年   77380篇
  1998年   19914篇
  1997年   17426篇
  1996年   17539篇
  1995年   16902篇
  1994年   15378篇
  1993年   14135篇
  1992年   57675篇
  1991年   55612篇
  1990年   53293篇
  1989年   51057篇
  1988年   46438篇
  1987年   45262篇
  1986年   42506篇
  1985年   40275篇
  1984年   29573篇
  1983年   25061篇
  1982年   14021篇
  1979年   25693篇
  1978年   17750篇
  1977年   15005篇
  1976年   13983篇
  1975年   14666篇
  1974年   17767篇
  1973年   17040篇
  1972年   15833篇
  1971年   14525篇
  1970年   13566篇
  1969年   12604篇
排序方式: 共有10000条查询结果,搜索用时 8 毫秒
91.
92.
Objective: Report efficacy findings from three clinical trials (one phase 2 and two phase 3 [OPUS-1, OPUS-2]) of lifitegrast ophthalmic solution 5.0% for treatment of dry eye disease (DED).

Research design and methods: Three 84-day, randomized, double-masked, placebo-controlled trials. Adults (≥18 years) with DED were randomized (1:1) to lifitegrast 5.0% or matching placebo. Changes from baseline to day 84 in signs and symptoms of DED were analyzed.

Main outcome measures: Phase 2, pre-specified endpoint: inferior corneal staining score (ICSS; 0–4); OPUS-1, coprimary endpoints: ICSS and visual-related function subscale (0–4 scale); OPUS-2, coprimary endpoints: ICSS and eye dryness score (EDS, VAS; 0–100).

Results: Fifty-eight participants were randomized to lifitegrast 5.0% and 58 to placebo in the phase 2 trial; 293 to lifitegrast and 295 to placebo in OPUS-1; 358 to lifitegrast and 360 to placebo in OPUS-2. In participants with mild-to-moderate baseline DED symptomatology, lifitegrast improved ICSS versus placebo in the phase 2 study (treatment effect, 0.35; 95% CI, 0.05–0.65; p?=?0.0209) and OPUS-1 (effect, 0.24; 95% CI, 0.10–0.38; p?=?0.0007). Among more symptomatic participants (baseline EDS ≥40, recent artificial tear use), lifitegrast improved EDS versus placebo in a post hoc analysis of OPUS-1 (effect, 13.34; 95% CI, 2.35–24.33; nominal p?=?0.0178) and in OPUS-2 (effect, 12.61; 95% CI, 8.51–16.70; p?<?0.0001).

Limitations: Trials were conducted over 12 weeks; efficacy beyond this period was not assessed.

Conclusions: Across three trials, lifitegrast improved ICSS in participants with mild-to-moderate baseline symptomatology in two studies, and EDS in participants with moderate-to-severe baseline symptomatology in two studies. Based on the overall findings from these trials, lifitegrast shows promise as a new treatment option for signs and symptoms of DED.  相似文献   
93.
94.
95.
96.
A 17‐year‐old boy presented with recurring severe dermatitis of the face of 5‐months duration that resembled impetigo. He had been treated with several courses of antibiotics without improvement. Biopsy showed changes consistent with allergic contact dermatitis and patch testing later revealed sensitization to benzoyl peroxide, which the patient had been using for the treatment of acne vulgaris.  相似文献   
97.
98.
99.
Investigative studies of white matter (WM) brain structures using diffusion MRI (dMRI) tractography frequently require manual WM bundle segmentation, often called “virtual dissection.” Human errors and personal decisions make these manual segmentations hard to reproduce, which have not yet been quantified by the dMRI community. It is our opinion that if the field of dMRI tractography wants to be taken seriously as a widespread clinical tool, it is imperative to harmonize WM bundle segmentations and develop protocols aimed to be used in clinical settings. The EADC‐ADNI Harmonized Hippocampal Protocol achieved such standardization through a series of steps that must be reproduced for every WM bundle. This article is an observation of the problematic. A specific bundle segmentation protocol was used in order to provide a real‐life example, but the contribution of this article is to discuss the need for reproducibility and standardized protocol, as for any measurement tool. This study required the participation of 11 experts and 13 nonexperts in neuroanatomy and “virtual dissection” across various laboratories and hospitals. Intra‐rater agreement (Dice score) was approximately 0.77, while inter‐rater was approximately 0.65. The protocol provided to participants was not necessarily optimal, but its design mimics, in essence, what will be required in future protocols. Reporting tractometry results such as average fractional anisotropy, volume or streamline count of a particular bundle without a sufficient reproducibility score could make the analysis and interpretations more difficult. Coordinated efforts by the diffusion MRI tractography community are needed to quantify and account for reproducibility of WM bundle extraction protocols in this era of open and collaborative science.  相似文献   
100.
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