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   278128篇
  免费   26431篇
  国内免费   15815篇
耳鼻咽喉   2985篇
儿科学   4283篇
妇产科学   4491篇
基础医学   32741篇
口腔科学   4418篇
临床医学   38591篇
内科学   43905篇
皮肤病学   3714篇
神经病学   18406篇
特种医学   9662篇
外国民族医学   138篇
外科学   29725篇
综合类   35831篇
现状与发展   58篇
一般理论   104篇
预防医学   20769篇
眼科学   7870篇
药学   26175篇
  194篇
中国医学   12406篇
肿瘤学   23908篇
  2024年   837篇
  2023年   4502篇
  2022年   10120篇
  2021年   13589篇
  2020年   10333篇
  2019年   9505篇
  2018年   10502篇
  2017年   9085篇
  2016年   8896篇
  2015年   12468篇
  2014年   15677篇
  2013年   14629篇
  2012年   20725篇
  2011年   22532篇
  2010年   13474篇
  2009年   10950篇
  2008年   14808篇
  2007年   14627篇
  2006年   14621篇
  2005年   14392篇
  2004年   9619篇
  2003年   8814篇
  2002年   7421篇
  2001年   5310篇
  2000年   5583篇
  1999年   6066篇
  1998年   4073篇
  1997年   3973篇
  1996年   3299篇
  1995年   3041篇
  1994年   2430篇
  1993年   1600篇
  1992年   2081篇
  1991年   1770篇
  1990年   1406篇
  1989年   1266篇
  1988年   1145篇
  1987年   992篇
  1986年   837篇
  1985年   635篇
  1984年   459篇
  1983年   347篇
  1982年   239篇
  1981年   213篇
  1980年   185篇
  1979年   181篇
  1978年   113篇
  1977年   112篇
  1975年   115篇
  1972年   88篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
ABSTRACT

The lack of stable housing can impair access and continuity of care for patients living with human immunodeficiency virus (HIV). This study investigated the relationship between housing status assessed at multiple time points and several core HIV-related outcomes within the same group of HIV patients experiencing homelessness. Patients with consistently stable housing (CSH) during the year were compared to patients who lacked CSH (non-CSH group). The study outcomes included HIV viral load (VL), CD4 counts, and health care utilization. Multivariable and propensity weighted analyses were used to assess outcomes adjusting for potential group differences. Of 208 patients, 88 (42%) had CSH and 120 (58%) were non-CSH. Patients with CSH had significantly higher proportion of VL suppression and higher mean CD4 counts. The frequency of nurse visits in the CSH group was less than a half of that in the non-CSH group. Patients with CSH were less likely to be admitted to the medical respite facility, and if admitted, their length of stay was about a half of that for the non-CSH group. Our study findings show that patients with CSH had significantly better HIV virologic control and immune status as well as improved health care utilization.  相似文献   
2.
3.
4.
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   

5.
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   
6.
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   
7.
8.
9.
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   
10.
This paper reviews the published literature on a group of developmental disorders of the retina and retinal pigment epithelium which result in focal abnormalities in one or both eyes. They are often asymptomatic, found on routine examination and are generally non-progressive. Some are associated with other systemic abnormalities.Subject terms: Retinal diseases, Eye abnormalities  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