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   228831篇
  免费   21268篇
  国内免费   16055篇
耳鼻咽喉   2004篇
儿科学   2360篇
妇产科学   3069篇
基础医学   27562篇
口腔科学   3849篇
临床医学   32007篇
内科学   34230篇
皮肤病学   2313篇
神经病学   12860篇
特种医学   8529篇
外国民族医学   141篇
外科学   22731篇
综合类   36948篇
现状与发展   58篇
一般理论   19篇
预防医学   13958篇
眼科学   6898篇
药学   23674篇
  200篇
中国医学   12846篇
肿瘤学   19898篇
  2024年   737篇
  2023年   3697篇
  2022年   9571篇
  2021年   11987篇
  2020年   8933篇
  2019年   7835篇
  2018年   8366篇
  2017年   7399篇
  2016年   6950篇
  2015年   10687篇
  2014年   13086篇
  2013年   11185篇
  2012年   16662篇
  2011年   18711篇
  2010年   10985篇
  2009年   8561篇
  2008年   11553篇
  2007年   11569篇
  2006年   11717篇
  2005年   11744篇
  2004年   7301篇
  2003年   6877篇
  2002年   5738篇
  2001年   5152篇
  2000年   5579篇
  1999年   5901篇
  1998年   3623篇
  1997年   3628篇
  1996年   2900篇
  1995年   2701篇
  1994年   2230篇
  1993年   1436篇
  1992年   1950篇
  1991年   1647篇
  1990年   1343篇
  1989年   1131篇
  1988年   1057篇
  1987年   915篇
  1986年   741篇
  1985年   546篇
  1984年   354篇
  1983年   251篇
  1982年   159篇
  1981年   153篇
  1980年   114篇
  1979年   147篇
  1978年   49篇
  1977年   53篇
  1975年   61篇
  1974年   61篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
2.
3.
1. To investigate Genkwa Flos hepatotoxicity, a cell metabolomics strategy combined with serum pharmacology was performed on human HL-7702 liver cells in this study.

2. Firstly, cell viability and biochemical indicators were determined and the cell morphology was observed to confirm the cell injury and develop a cell hepatotoxicity model. Then, with the help of cell metabolomics based on UPLC-MS, the Genkwa Flos group samples were completely separated from the blank group samples in the score plots and seven upregulated as well as two down-regulated putative biomarkers in the loading plot were identified and confirmed. Besides, two signal molecules and four enzymes involved in biosynthesis pathway of lysophosphatidylcholine and the sphingosine kinase/sphingosine-1-phosphate pathway were determined to investigate the relationship between Genkwa Flos hepatotoxicity and these two classic pathways. Finally, the metabolic pathways related to specific biomarkers and two classic metabolic pathways were analyzed to explain the possible mechanism of Genkwa Flos hepatotoxicity.

3. Based on the results, lipid peroxidation and oxidative stress, phospholipase A2/lysophosphatidylcholine pathway, the disturbance of sphingosine-1-phosphate metabolic profile centered on sphingosine kinase/sphingosine-1-phosphate pathway and fatty acid metabolism might be critical participators in the progression of liver injury induced by Genkwa Flos.  相似文献   

4.
目的:探究替米沙坦对冠心病合并糖尿病肾病患者疗效的影响情况。方法:56例探究目标对象均为某院接收的冠心病合并糖尿病肾病患者,挑选时间2018年6月~2019年6月。将"计算机表法"作为分组的参考,分配为参照组(n=28例)执行依那普利治疗,探究组(n=28例)执行替米沙坦治疗。结果:探究组的LVEF、LVEDd、肌酐、24h尿蛋白4项指标与参照组相比,差异有统计学意义(P<0.05);收缩压、舒张压、空腹血糖、餐后2h血糖4项指标与参照组相比,差异没有统计学意义(P>0.05)。结论:冠心病合并糖尿病肾病患者选择替米沙坦治疗后,心室功能的重构以及肾脏预后结局均得到改善,且临床效果比依那普利好,值得借鉴。  相似文献   
5.
Abstract

Background

Comorbidities are commonly seen in patients with coronavirus disease 2019 (COVID-19), but the clinical implication is not yet well-delineated. We aim to characterize the prevalence and clinical implications of comorbidities in patients with COVID-19.  相似文献   
6.
7.
8.
9.
In order to solve the problem of long-term (>9 months) efficacy in the treatment of Alzheimer''s disease (AD) by conventional therapy (CT), a staged and multiply-targeted sequential therapy based on the evolvement of patterns (STEP) was developed. Its main innovations include: (1) the time order of evolution of patterns defined by Chinese medicine (CM) in AD was found, that is, "the orderly pattern evolution starting from Shen (Kidney) deficiency, progressing to phlegm, stasis and fire, and worsening to severe toxin as well as functional collapse"; (2) the cascade hypothesis of Shen deficiency in AD and its sequential therapy based on Shen-reinforcing was proposed, that is, "reinforcing Shen in the early stage and throughout the whole process, resolving phlegm, activating blood and purging fire in the middle stage, detoxifying and replenishing vitality to stop the collapse in the advanced stage", and through meta-analysis, clinical drug use was optimized, thus the leap from "inferential selection" to "evidence-based selection" was realized; (3) the STEP regimen combined with CT maintained cognitive and behavioral stability in AD patients for at least 12 months, with cognitive enhancement and behavioral synergy after 9 months, and cognitive benefit was superior to CT at 9, 12, 15, 18, 21, and 24 months, respectively. The 2-year cognitive improvement rate was increased by 25.64% (P=0.020) and the cognitive deterioration rate was decreased by 48.71% (P=0.000). Among them, the cognitive and functional benefits of Shen-reinforcing therapy for very early AD (350 cases) for 1 year were better than the placebo (P<0.001), and the dementia conversion rate was reduced by 8.85% (P=0.002). The behavioral symptomatic relief of patients with vascular dementia received fire-purging therapy (540 cases) was superior to those received CT (P=0.016). These data suggested that the STEP regimen has synergistic effects on CTs at least in terms of cognitive benefit, and the earlier the use, the greater the benefit will have. Therefore, the STEP regimen should be considered as one of the clinical options, particularly for the dearth of effective pharmaceutical or immunological interventions that are currently available for AD.  相似文献   
10.
ABSTRACT

Purpose

New instrument-based techniques for anterior chamber (AC) cell counting can offer automation and objectivity above clinician assessment. This review aims to identify such instruments and its correlation with clinician estimates.  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