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   734878篇
  免费   64911篇
  国内免费   48230篇
耳鼻咽喉   5925篇
儿科学   8740篇
妇产科学   10443篇
基础医学   83318篇
口腔科学   12382篇
临床医学   101062篇
内科学   104579篇
皮肤病学   7721篇
神经病学   37722篇
特种医学   26565篇
外国民族医学   391篇
外科学   70300篇
综合类   126531篇
现状与发展   153篇
一般理论   92篇
预防医学   50482篇
眼科学   21094篇
药学   78203篇
  716篇
中国医学   43689篇
肿瘤学   57911篇
  2024年   2243篇
  2023年   9877篇
  2022年   25970篇
  2021年   33183篇
  2020年   25556篇
  2019年   21572篇
  2018年   23129篇
  2017年   21659篇
  2016年   20153篇
  2015年   30629篇
  2014年   38656篇
  2013年   35589篇
  2012年   52603篇
  2011年   59510篇
  2010年   39142篇
  2009年   31679篇
  2008年   40388篇
  2007年   40683篇
  2006年   39879篇
  2005年   39210篇
  2004年   25743篇
  2003年   24153篇
  2002年   20428篇
  2001年   18280篇
  2000年   18657篇
  1999年   19514篇
  1998年   12055篇
  1997年   11873篇
  1996年   9195篇
  1995年   8659篇
  1994年   7340篇
  1993年   4829篇
  1992年   6296篇
  1991年   5391篇
  1990年   4514篇
  1989年   3925篇
  1988年   3346篇
  1987年   2978篇
  1986年   2431篇
  1985年   1853篇
  1984年   1112篇
  1983年   804篇
  1982年   447篇
  1981年   452篇
  1980年   363篇
  1979年   457篇
  1978年   213篇
  1977年   164篇
  1974年   158篇
  1973年   132篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
42.
43.
44.
45.
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   
46.
47.
48.
目的探讨指压天枢穴加腹部按摩联合番泻叶在静脉肾盂造影患者中的应用效果。方法选取我院2018年12月至2019年8月期间行静脉肾盂造影的120例患者,随机分为两组各60例。对照组给予番泻叶,观察组给予天枢穴指压加腹部按摩联合番泻叶,比较两组的肠道清洁力度和不良反应情况。结果治疗后,观察组的肠道清洁力度明显高于对照组(P <0.05);观察组的不良反应发生率为6.67%,明显低于对照组的23.33%(P <0.05)。结论静脉肾盂造影患者采用指压天枢穴加腹部按摩联合番泻叶的效果较好,可提高肠道清洁力度,降低不良反应发生率。  相似文献   
49.
The progress of modern medicine would be impossible without the use of general anesthetics (GAs). Despite advancements in refining anesthesia approaches, the effects of GAs are not fully reversible upon GA withdrawal. Neurocognitive deficiencies attributed to GA exposure may persist in neonates or endure for weeks to years in the elderly. Human studies on the mechanisms of the long-term adverse effects of GAs are needed to improve the safety of general anesthesia but they are hampered not only by ethical limitations specific to human research, but also by a lack of specific biological markers that can be used in human studies to safely and objectively study such effects. The latter can primarily be attributed to an insufficient understanding of the full range of the biological effects induced by GAs and the molecular mechanisms mediating such effects even in rodents, which are far more extensively studied than any other species. Our most recent experimental findings in rodents suggest that GAs may adversely affect many more people than is currently anticipated. Specifically, we have shown that anesthesia with the commonly used GA sevoflurane induces in exposed animals not only neuroendocrine abnormalities (somatic effects), but also epigenetic reprogramming of germ cells (germ cell effects). The latter may pass the neurobehavioral effects of parental sevoflurane exposure to the offspring, who may be affected even at levels of anesthesia that are not harmful to the exposed parents. The large number of patients who require general anesthesia, the even larger number of their future unexposed offspring whose health may be affected, and a growing number of neurodevelopmental disorders of unknown etiology underscore the translational importance of investigating the intergenerational effects of GAs. In this mini review, we discuss emerging experimental findings on neuroendocrine, epigenetic, and intergenerational effects of GAs.  相似文献   
50.
手术治疗精索静脉曲张在改善精液质量、提高配偶自然怀孕率和缓解局部疼痛症状中的作用已为多数医生所认同。随着手术方式的改进,越来越多的精索静脉曲张患者接受手术治疗,然而,临床对手术后患者的管理还重视不够。本文系统介绍了对精索静脉曲张手术后患者的疗效判断和后续治疗选择,包括观察随诊、非手术治疗方法和再手术。  相似文献   
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