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   21206篇
  免费   1334篇
  国内免费   114篇
耳鼻咽喉   313篇
儿科学   574篇
妇产科学   330篇
基础医学   2433篇
口腔科学   637篇
临床医学   1779篇
内科学   4677篇
皮肤病学   468篇
神经病学   1218篇
特种医学   738篇
外国民族医学   7篇
外科学   3284篇
综合类   499篇
一般理论   12篇
预防医学   1423篇
眼科学   718篇
药学   1978篇
  1篇
中国医学   232篇
肿瘤学   1333篇
  2023年   255篇
  2022年   656篇
  2021年   1040篇
  2020年   633篇
  2019年   852篇
  2018年   997篇
  2017年   633篇
  2016年   776篇
  2015年   781篇
  2014年   1059篇
  2013年   1278篇
  2012年   1832篇
  2011年   1817篇
  2010年   1123篇
  2009年   781篇
  2008年   1201篇
  2007年   1173篇
  2006年   991篇
  2005年   870篇
  2004年   696篇
  2003年   612篇
  2002年   526篇
  2001年   231篇
  2000年   196篇
  1999年   192篇
  1998年   97篇
  1997年   58篇
  1996年   63篇
  1995年   59篇
  1994年   61篇
  1993年   61篇
  1992年   77篇
  1991年   97篇
  1990年   83篇
  1989年   92篇
  1988年   62篇
  1987年   68篇
  1986年   52篇
  1985年   49篇
  1984年   46篇
  1983年   24篇
  1982年   29篇
  1981年   32篇
  1980年   29篇
  1979年   47篇
  1978年   34篇
  1977年   26篇
  1975年   36篇
  1974年   26篇
  1973年   21篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
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   
4.
5.
Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital condition. It responds well to early diagnosis and treatment, but otherwise the prognosis is poor. We present our case series of 12 patients (mean age, 2 ± 2.58 yr; age range, 2 mo–8 yr), emphasizing the diagnostic process and discussing our surgical results. The diagnosis of ALCAPA should be suspected in infants who have dilated cardiomyopathy with electrocardiographic changes that suggest ischemia, and in older children who have isolated mitral regurgitation. When clinical suspicion is high, the results of 2-dimensional echocardiography combined with color-flow Doppler studies in expert hands can establish the diagnosis, thus avoiding angiography in critically ill infants. The treatment of choice in our patients was transfer and reimplantation of the left coronary artery onto the ascending aorta. There were 2 deaths: both were infants in extremis who underwent emergency surgery. An older child with severe ventricular dysfunction was given mechanical ventricular assistance and then heart transplantation. As of this report, all 10 survivors remained well and asymptomatic.  相似文献   
6.
Doxorubicin (DOX) is the most commonly used anticancer drug; however, it has limited use because prolonged administration may result in severe cardiotoxicity. Simvastatin (SIM), generally prescribed for hypercholesterolaemia, has also shown salubrious results in the monotherapy or combinational drug therapy of different cancers in various models. Nanoparticle drug delivery systems are a novel way of improving therapeutics and also improving the absorption and specificity of drugs towards tumour cells. In this study, we exploited this technology to increase drug specificity and minimize imminent adverse effects. In this study, the antitumour activity of the combination formulas of DOX and SIM, either loaded in water (DOX‐SIM‐Solution) or nanoemulsions (NEs) (DOX‐SIM‐NE), was evaluated in a Swiss albino mouse model of Ehrlich ascites carcinoma. The anticancer effect was assessed by quantifying the change in body weight, mean survival time, and percent increase in lifespan (%ILS), determining haematological and serum biochemical parameters (liver function test, kidney function test and lipid profile parameters) as well as studying the histopathological alterations in liver tissues. We observed a clear increase in %ILS of the DOX‐SIM‐Solution group (265.30) that was double the %ILS of the DOX‐SIM‐NE group (134.70). However, DOX‐SIM‐NE had a non‐toxic effect on the haematological parameters, whereas DOX‐SIM‐Solution increased the levels of haemoglobin and lymphocytes. Furthermore, the encapsulation of SIM and DOX into NEs improved the levels of all serum biochemical parameters compared to the DOX‐SIM‐Solution. A reduction in the side effects of DOX‐SIM‐NE on the liver was also established using light microscopy, which revealed that the morphologies of the hepatocytes of the mice were less affected by administration of the DOX‐SIM‐NE treatment than with the DOX‐SIM‐Solution treatment. The study showed that incorporating SIM into the DOX‐loaded‐NE formulation remarkably improved its efficiency and simultaneously reduced its adverse effects.  相似文献   
7.
This bibliometric study assessed periodontal/implant articles that were part of the five most‐cited dental articles in each of the years 2005‐2019. Periodontal/implant articles made up one to four articles in each of 14 years and totaled 40% of the yearly five most‐cited dental articles. The three core periodontal journals (Journal of Clinical Periodontology, Journal of Periodontology, and Periodontology 2000) increased ~50%‐100% in Journal Impact Factor from 2005 to 2015 and were among the 10 most‐cited dental journals in the 2015‐2019 period. The Journal of Clinical Periodontology and Periodontology 2000 were in several years assigned the highest Journal Impact Factor in dentistry. In summary, periodontal journals continue to publish high‐impact articles that are relevant for both oral health care and medicine.  相似文献   
8.
The floating metacarpal bone is a result of simultaneous fracture-dislocation of both carpometacarpal and metacarpophalangeal joints. This rare entity may be associated with other hand injuries. Here we present a floating index metacarpal with concomitant 3rd–5th carpometacarpal fracture-dislocations. Excellent functional short-term result was achieved after open metacarpopha langeal reduction and closed carpometacarpal reduction and percutaneous pinning.  相似文献   
9.
Urothelial cell carcinoma (UCC) of the bladder is one of the most common malignancies, causing considerable morbidity and mortality worldwide. It is unique among the epithelial carcinomas as two distinct pathways to tumourigenesis appear to exist: low grade, recurring papillary tumours usually contain oncogenic mutations in FGFR3 or HRAS whereas high grade, muscle invasive tumours with metastatic potential generally have defects in the pathways controlled by the tumour suppressors p53 and retinoblastoma. Over the last two decades, a number of transgenic mouse models of UCC, containing deletions or mutations of key tumour suppressor genes or oncogenes, have helped us understand the mechanisms behind tumour development. In this summary, I present my work investigating the role of the WNT signalling cascade in UCC.  相似文献   
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