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   11882篇
  免费   899篇
  国内免费   587篇
耳鼻咽喉   117篇
儿科学   165篇
妇产科学   135篇
基础医学   987篇
口腔科学   220篇
临床医学   1453篇
内科学   1808篇
皮肤病学   115篇
神经病学   493篇
特种医学   452篇
外科学   1511篇
综合类   2049篇
一般理论   7篇
预防医学   1147篇
眼科学   192篇
药学   1083篇
  5篇
中国医学   576篇
肿瘤学   853篇
  2024年   12篇
  2023年   52篇
  2022年   130篇
  2021年   239篇
  2020年   210篇
  2019年   187篇
  2018年   209篇
  2017年   236篇
  2016年   255篇
  2015年   415篇
  2014年   520篇
  2013年   635篇
  2012年   1053篇
  2011年   1228篇
  2010年   999篇
  2009年   832篇
  2008年   968篇
  2007年   973篇
  2006年   844篇
  2005年   795篇
  2004年   550篇
  2003年   418篇
  2002年   316篇
  2001年   254篇
  2000年   226篇
  1999年   117篇
  1998年   45篇
  1997年   47篇
  1996年   35篇
  1995年   30篇
  1994年   39篇
  1993年   23篇
  1992年   51篇
  1991年   63篇
  1990年   50篇
  1989年   34篇
  1988年   27篇
  1987年   18篇
  1986年   30篇
  1985年   28篇
  1984年   19篇
  1983年   18篇
  1981年   8篇
  1980年   13篇
  1979年   18篇
  1978年   20篇
  1977年   11篇
  1976年   9篇
  1974年   11篇
  1973年   8篇
排序方式: 共有10000条查询结果,搜索用时 62 毫秒
1.
2.
Levels of the soluble form of the triggering receptor expressed on myeloid cells (sTREM)-1 are elevated in severe sepsis. However, it is not known whether sTREM-1 measurements can distinguish milder bacterial infections from noninfectious inflammation. The present authors studied whether serum sTREM-1 levels differ in community-acquired pneumonia, exacerbations of chronic obstructive pulmonary disease (COPD), asthma and controls, and whether sTREM-1 may be used as a surrogate marker for the need for antibiotics. Serum sTREM-1 levels in 150 patients with pneumonia, COPD and asthma exacerbations and 62 healthy controls were measured. Serum sTREM-1 levels were significantly elevated in pneumonia (median 295.2 ng x mL(-1)), COPD (280.3 ng x mL(-1)) and asthma exacerbations (184.0 ng x mL(-1)) compared with controls (83.1 ng x mL(-1)). Levels were higher in pneumonia and Anthonisen type 1 COPD exacerbations than in type 2 and 3 COPD and asthma exacerbations. The area under the receiver operating characteristics curve for sTREM-1 as a surrogate marker for the need for antibiotics was 0.77. Serum levels of the soluble form of the triggering receptor expressed on myeloid cells-1 were elevated predominantly in pneumonia and Anthonisen type 1 COPD exacerbations versus type 2 and 3 chronic obstructive pulmonary disease exacerbations, asthma and controls. Serum levels of the soluble form of the triggering receptor expressed on myeloid cells-1 has moderate but insufficient accuracy as a surrogate marker for the need for antibiotics in lower respiratory tract infections.  相似文献   
3.
白细胞介素-8(IL-8)作为中性粒细胞趋化因子和促血管生成因子,受到人们的重视。研究表明,IL-8促进卵细胞的发育、成熟,诱发排卵;在输卵管和子宫内膜的表达随月经周期而变化;参与胚泡着床和胚胎发育。本文综述IL-8在哺乳动物生殖过程中的重要作用。  相似文献   
4.
M Y Fan  Z P Lum  X W Fu  L Levesque  I T Tai  A M Sun 《Diabetes》1990,39(4):519-522
Prolonged survival of pancreatic islet allografts implanted in diabetic BB rats was achieved by encapsulation of individual islets in a protective biocompatible alginate-polylysine-alginate membrane without immunosuppression. Intraperitoneal transplantation of the encapsulated islets reversed the diabetic state of the recipients within 3 days and maintained normoglycemia for 190 days. Normal body weight and urine volume were maintained during this period, and no cataracts were detected in the transplant recipients. In contrast, control rats receiving transplants of unencapsulated islets experienced normoglycemia for less than 2 wk. These results demonstrated that microencapsulation can protect allografted islets from both graft rejection and autoimmune destruction without immunosuppression in an animal model that mimics human insulin-dependent diabetes.  相似文献   
5.
We investigate the controlled release of lidocaine hydrochloride from the doped silica-based xerogels. In the xerogel preparation, tetraethoxysilane (TEOS), methyltriethoxysilane (MTES), and propyltriethoxysilane (PTES) are used as precursors, and a nonionic surfactant Igepal CO 720 is used as a dopant. The experimental results suggest that the release of lidocaine hydrochloride can be easily controlled by partially substituting TEOS with the organosilanes, and/or by adding the dopant. Adding the organosilane precursors lowers the release of both the drug and the surfactant in the order of TEOS, MTES/TEOS, and PTES/TEOS xerogels. The release from the PTES/TEOS xerogels is much lower than that from the other xerogels. The release of lidocaine hydrochloride is obviously suppressed by the addition of Igepal CO 720, while the release of Igepal CO 720 is slightly promoted by the addition of the drug. The overall release process is found to be diffusion-controlled, and the release behaviors can be well explained by considering the effects of the textual properties of the xerogels and the interactions among the drug, the surfactant, and the xerogel matrices.  相似文献   
6.
目的 探讨不同年龄段、恶性程度不同的多节段髓内星形细胞瘤患者的诊治特点.方法 21例多节段(3个椎体节段以上)髓内星形细胞瘤患者均行后正中入路显微镜下肿瘤切除术,以UOA分值差(术后UOA和术前UOA差值)评估手术效果.以Logistic回归和多元线性同归分析统计学数据.结果 肿瘤性质直接影响肿瘤的切除程度(X2=10.41,P=0.03),高度恶性肿瘤只能大部切除或减压.年龄(X2=12.53,P=0.01)、肿瘤性质(X2=16.44,P=0.002)和部位(X2=27.12,P=0.04)影响近期手术效果(UOA分值差);青少年患者、低度恶性肿瘤手术效果较好,单纯累及胸段的患者手术效果差.结论 低度恶性或青少年多节段髓内星形细胞瘤患者应尽早手术,术后疗效满意.  相似文献   
7.

Purpose  

Hepatitis B virus (HBV) is endemic in Bangladesh, and the quality of life (QoL) of these patients remains unknown as there is no instrument available in the native language. In this study, we translated the 56-item Hepatitis Quality of Life Questionnaire (HQLQ) into Bengali and evaluated its validity and reliability.  相似文献   
8.
9.
10.
Radiotherapy(RT)is an important ap-proach for treatment of esophageal carcinoma(EC),especially for patients who have missedthe chance of surgical section.The efficacy ofRTis not satisfactory for its1-year,3-year and5-year survival rates being merely50%,20%,and10%respectively(1).Researches in recent years showed thatbetter efficacy can be obtained by combiningRTwith Chinese herbal medicines for EC thatincapable to be resected.Kang ai Injection(康艾注射液,KAI)is a Chinese herbal prep-arati…  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