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   23937篇
  免费   1497篇
  国内免费   159篇
耳鼻咽喉   263篇
儿科学   632篇
妇产科学   664篇
基础医学   2682篇
口腔科学   992篇
临床医学   2093篇
内科学   5005篇
皮肤病学   466篇
神经病学   1447篇
特种医学   588篇
外国民族医学   12篇
外科学   3533篇
综合类   622篇
一般理论   16篇
预防医学   1919篇
眼科学   846篇
药学   2229篇
中国医学   242篇
肿瘤学   1342篇
  2024年   24篇
  2023年   258篇
  2022年   271篇
  2021年   1246篇
  2020年   842篇
  2019年   1017篇
  2018年   1224篇
  2017年   852篇
  2016年   938篇
  2015年   958篇
  2014年   1281篇
  2013年   1527篇
  2012年   2084篇
  2011年   2102篇
  2010年   1254篇
  2009年   996篇
  2008年   1413篇
  2007年   1337篇
  2006年   1179篇
  2005年   1046篇
  2004年   810篇
  2003年   703篇
  2002年   589篇
  2001年   134篇
  2000年   135篇
  1999年   129篇
  1998年   93篇
  1997年   75篇
  1996年   75篇
  1995年   59篇
  1994年   42篇
  1993年   53篇
  1992年   60篇
  1991年   61篇
  1990年   65篇
  1989年   59篇
  1988年   56篇
  1987年   55篇
  1986年   44篇
  1985年   35篇
  1984年   38篇
  1983年   39篇
  1982年   23篇
  1980年   24篇
  1979年   26篇
  1978年   24篇
  1977年   24篇
  1974年   23篇
  1973年   25篇
  1972年   20篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
Lasers in Medical Science - Melasma is a chronic, dark brown–pigmented patches and macules commonly on the face. Many treatment modalities for melasma have been used as hydroquinone, laser...  相似文献   
2.
3.
4.
Objective: To determine whether packed red blood cell (PRBC) transfusion affects post-prandial superior mesenteric artery blood flow velocities (SMA BFVs) in very-low birth weight (VLBW) neonates and if so, at what time point after transfusion restoration of previous SMA BFV patterns occurs.

Design/Methods: VLBW pre-term neonates, older than 14 days and tolerating bolus enteral feedings administered every 3?h were enrolled in this prospective observational study. Pulsed Doppler ultrasound was used to measure pre- and post-prandial (at 45?min) time-averaged mean, peak and end diastolic velocities (TAMV, PSV, EDV) immediately before and after 15?ml/kg of PRBC transfusion was given over 3?h; patent ductus arteriosus (PDA) status was also evaluated. Subsequent pre- and post-prandial SMA BFVs were recorded 24 and 48?h after the transfusion.

Results: Pre- and post-prandial measurements were obtained for 21 out of 25 enrolled infants. Post-prandial SMA BFVs were attenuated during the feedings immediately after transfusion; at 24 and 48?h after transfusion, changes in post-prandial SMA BFVs were similar to those measured prior to transfusion; the presence of the PDA did not affect results.

Conclusions: PRBC transfusion blunted SMA BFV responses to feedings immediately after the transfusion with normalization observed 24?h post-transfusion.  相似文献   
5.
6.
ABSTRACT

Purpose

To investigate the expression of IL-11 and its receptor IL-11Rα and to quantify density of CD163+ M2 macrophages in proliferative diabetic retinopathy (PDR).  相似文献   
7.
Nonalcoholic fatty liver disease (NAFLD) is a major cause of liver‐related morbidity; its prevalence is elevating due to the rising epidemic of obesity. Several clinical trials have examined the effects of curcumin supplementation on anthropometric variables in NAFLD patients with inconclusive results. This dose–response meta‐analysis aimed to evaluate the impact of curcumin supplementation on body mass index (BMI), body weight, and waist circumference (WC) in patients with NAFLD. A systematic review of the literature was conducted using PubMed/Medline, ISI Web of Science, Scopus, Cochrane Library, EMBASE, Google Scholar, Sid.ir, and Magiran.com to identify eligible studies up to March 2019. A meta‐analysis of eligible studies was performed using the random‐effects model to estimate the pooled effect size. Eight randomized controlled trials with 520 participants (curcumin group = 265 and placebo group = 255) were included. Supplementation dose and duration ranged from 70 to 3,000 mg/day and 8 to 12 weeks, respectively. Curcumin supplementation significantly reduced BMI (weighted mean difference [WMD] = ?0.34 kg/m2, 95% CI [?0.64, ?0.04], p < .05) and WC (WMD = ?2.12 cm, 95% CI [?3.26, ?0.98], p < .001). However, no significant effects of curcumin supplementation on body weight were found. These results suggest that curcumin supplementation might have a positive effect on visceral fat and abdominal obesity that have been associated with NAFLD.  相似文献   
8.
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