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   2333513篇
  免费   187879篇
  国内免费   7495篇
耳鼻咽喉   31978篇
儿科学   78416篇
妇产科学   64264篇
基础医学   326074篇
口腔科学   63878篇
临床医学   208850篇
内科学   471402篇
皮肤病学   53361篇
神经病学   188514篇
特种医学   94702篇
外国民族医学   883篇
外科学   362375篇
综合类   53105篇
现状与发展   3篇
一般理论   747篇
预防医学   183298篇
眼科学   51012篇
药学   168769篇
  7篇
中国医学   4189篇
肿瘤学   123060篇
  2018年   23671篇
  2017年   18248篇
  2016年   21199篇
  2015年   23814篇
  2014年   33205篇
  2013年   50330篇
  2012年   64940篇
  2011年   69470篇
  2010年   42575篇
  2009年   41080篇
  2008年   65605篇
  2007年   70262篇
  2006年   71335篇
  2005年   69135篇
  2004年   66724篇
  2003年   64964篇
  2002年   62697篇
  2001年   112431篇
  2000年   116348篇
  1999年   97948篇
  1998年   28443篇
  1997年   25590篇
  1996年   26521篇
  1995年   26122篇
  1994年   24524篇
  1993年   22886篇
  1992年   79851篇
  1991年   78048篇
  1990年   75470篇
  1989年   72105篇
  1988年   66566篇
  1987年   65332篇
  1986年   61351篇
  1985年   59029篇
  1984年   44861篇
  1983年   37791篇
  1982年   22914篇
  1981年   20698篇
  1980年   19105篇
  1979年   40398篇
  1978年   28823篇
  1977年   24477篇
  1976年   22549篇
  1975年   23938篇
  1974年   28138篇
  1973年   27009篇
  1972年   24893篇
  1971年   22896篇
  1970年   21230篇
  1969年   19574篇
排序方式: 共有10000条查询结果,搜索用时 98 毫秒
101.
A 42‐year‐old man presented with a viral prodrome and tested positive for influenza A. He rapidly deteriorated developing cardiogenic shock, rhabdomyolysis, and acute kidney injury. Patient improved 1 week later with supportive measures including vasopressors, inotropes, and an intraaortic balloon pump. We report this case as it highlights the discordance between echocardiographic ventricular wall thickening as a result of myocardial edema, and electrocardiographic findings at presentation, with a reversal in findings at time of resolution. Additionally, there was some suggestion of a regional pattern to the reduced longitudinal strain.  相似文献   
102.
103.
104.
BACKGROUND Metabolic disturbances including changes in serum calcium,magnesium or phosphate(P) influence the prevalence of type 2 diabetes mellitus(DM).We assessed the importance of serum P in elderly patients with type 2 DM vs nondiabetes mellitus(non-DM) in relation to renal function.AIM To determine the association between serum P and serum glucose or insulin resistance in diabetic and non-diabetic patients.METHODS One hundred-ten subjects with a mean age of 69.02±14.3 years were enrolled.Twenty-nine of the participants had type 2 DM(26.4%).The incidence of hypertension,smoking and receiving vitamin D(vitD) derivates were recorded.The participants were classified by both estimated glomerular filtration rate(eGFR) and albuminuria categories according to the Kidney Disease Improving Global Outcomes 2012 criteria.RESULTS We divided the patients in two groups according to the P cut-off point related to DM value.A comparison between high and low P showed that body mass index30.2±6.3 vs 28.1±4.6(P=0.04),mean glucose 63.6 vs 50.2(P=0.03),uric acid 6.7±1.6 vs 6.09±1.7(P=0.05),mean intact-parathyroid hormone 68.06 vs 47.4(P=0.001),systolic blood pressure 147.4±16.7 vs 140..2±16.1(P=0.02),mean albuminuria 63.2 vs 50.6(P=0.04) and eGFR 45.6±22.1 vs 55.4±21.5(P=0.02)were significantly different.χ~2 tests showed a significant association between high P and DM,hypertension,receiving vitD,smoking and eGFR stage(χ~2=6.3,P=0.01,χ~2=3.9,P=0.03,χ~2=6.9,P=0.009,χ~2=7.04,P=0.01 and χ~2=7.36,P=0.04,respectively).The adjusted model showed that older age,female gender and increased body mass index were significant predictors of type 2 DM when entering the covariates.CONCLUSION High serum P contributes to vascular and metabolic disturbances in elderly patients with type 2 DM and renal impairment.  相似文献   
105.
106.
107.
108.
109.
Porocarcinoma is an unusual, locally aggressive and potentially fatal neoplasm. Several cutaneous malignancies have been described in association with porocarcinoma, including squamous cell carcinoma, basal cell carcinoma and tricholemmal carcinoma. Previous reports have indicated that the occurrence of malignant tumours in combination with porocarcinoma is extremely rare, in particular with regard to Bowen disease (BD). We report an uncommon case of porocarcinoma occurring synchronously in a single BD lesion in a 63‐year‐old woman with multiple BD lesions. The clinical and histological findings confirmed this diagnosis.  相似文献   
110.
Advancement in microelectromechanical system has facilitated the microfabrication of polymeric substrates and the development of the novel class of controlled drug delivery devices. These vehicles have specifically tailored three dimensional physical and chemical features which together, provide the capacity to target cell, stimulate unidirectional controlled release of therapeutics and augment permeation across the barriers. Apart from drug delivery devices microfabrication technology’s offer exciting prospects to generate biomimetic gastrointestinal tract models. BioMEMS are capable of analysing biochemical liquid sample like solution of metabolites, macromolecules, proteins, nucleic acid, cells and viruses. This review summarized multidisciplinary application of biomedical microelectromechanical systems in drug delivery and its potential in analytical procedures.  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