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   1076223篇
  免费   71828篇
  国内免费   1366篇
耳鼻咽喉   15041篇
儿科学   34651篇
妇产科学   28666篇
基础医学   153557篇
口腔科学   29573篇
临床医学   95107篇
内科学   203887篇
皮肤病学   24398篇
神经病学   81602篇
特种医学   43004篇
外国民族医学   201篇
外科学   163288篇
综合类   21716篇
现状与发展   1篇
一般理论   263篇
预防医学   74758篇
眼科学   24548篇
药学   86239篇
  7篇
中国医学   2814篇
肿瘤学   66096篇
  2019年   7783篇
  2018年   11327篇
  2017年   8928篇
  2016年   10114篇
  2015年   11280篇
  2014年   15295篇
  2013年   22256篇
  2012年   30615篇
  2011年   32357篇
  2010年   18982篇
  2009年   17848篇
  2008年   30013篇
  2007年   32125篇
  2006年   32765篇
  2005年   31087篇
  2004年   29780篇
  2003年   28609篇
  2002年   27579篇
  2001年   60079篇
  2000年   61518篇
  1999年   50974篇
  1998年   12459篇
  1997年   11008篇
  1996年   11025篇
  1995年   10327篇
  1994年   9350篇
  1993年   8864篇
  1992年   37820篇
  1991年   36297篇
  1990年   35768篇
  1989年   34303篇
  1988年   30888篇
  1987年   29998篇
  1986年   28234篇
  1985年   26473篇
  1984年   19202篇
  1983年   16135篇
  1982年   8845篇
  1979年   17055篇
  1978年   11414篇
  1977年   10238篇
  1976年   8843篇
  1975年   10079篇
  1974年   11663篇
  1973年   11284篇
  1972年   10770篇
  1971年   10102篇
  1970年   9259篇
  1969年   8948篇
  1968年   7935篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.
83.
84.
INTRODUCTION: Vasopressin, mainly through the V1a-receptor, is thought to be a major player in the maintenance of hyperfiltration. Its inhibition could therefore lead to a decrease in progression of chronic renal failure. To this end, the effect of the vasopressin V1a-receptor-selective antagonist, YM218, was studied on proteinuria and focal glomerulosclerosis in early and late intervention after 5/6 nephrectomy in rats, and compared with an angiotensin-converting enzyme inhibitor (ACE-I). MATERIALS AND METHODS: After 5/6 nephrectomy, early intervention was performed between week 2 and 10 thereafter with the V1a-receptor-selective antagonist (VRA, 10 mg/kg/day, n=10), enalapril (ACE-I, 10 mg/kg/day, n=9), or vehicle (n=8). Late intervention was performed in another group between week 6 and 12 with VRA (10 mg/kg/day, n=7), lisinopril (ACE-I, 5 mg/kg/day, n=7), or vehicle (n=7). RESULTS: In early intervention, proteinuria and focal glomerulosclerosis were significantly decreased by VRA compared to vehicle (44+7% and 59+8% respectively). ACE-I significantly decreased proteinuria (67+7%) and a trend towards a decrease in focal glomerulosclerosis was observed (30+18%). In late intervention, VRA did not decrease proteinuria and focal glomerulosclerosis compared to vehicle (21+20% and 0%, respectively), ACE-I significantly lowered proteinuria (92+2%) and a focal glomerulosclerosis (69+1%) lowering trend was observed. CONCLUSION: These results indicate that VRA may protect against early progression of renal injury after 5/6 nephrectomy, whereas its effectiveness seems limited in established renal damage.  相似文献   
85.
86.
Both vascular surgery and endovascular interventions traumatise the arterial wall, especially the endothelium. The vessel responds with neointimal hyperplasia and/or constrictive remodelling, and this is still the limiting factor in curative interventions. Stent placement prevents constrictive remodelling but is the main trigger for in-stent restenosis. Hyperproliferation of neointimal tissue is the main response to arterial thrombosis, local inflammation or medio-intimal injury such as occurs, for example, after balloon dilatation in the region of arterial anastomoses or of a thrombectomy (Fogarty-manoeuvre). At present, research on prevention of restenosis is focused on inhibiting neointimal hyperproliferation by using drug-eluting stents, and especially sirolimus- or paclitaxel-eluting stents. In addition, further experimental research work is in progress, with the aim of esablishing new treatment regimens and solving the problem of neointimal formation, thrombosis and constrictive remodelling. These include both local and systemic pharmacological therapy, brachy- and laser therapy, and many genetic treatment options, some of which are currently the subjects of experimental studies and early-stage clinical trials. Gene therapy seems like a promising way of preventing restenosis, but has not yet been tested in clinical trials. In the near future, selective, simultaneous, and perhaps even polyphasic regulation for gene silencing of two or more genes involved in the development of restenosis could improve the long-term patency rate.  相似文献   
87.
88.
89.
Mycophenolate mofetil (MMF) used in a triple-drug regimen has been shown to decrease acute rejection rates, compared to a double-drug regimen. The impact of MMF on late acute rejection (LAR) episodes has not been well described. To investigate the risk of LAR (rejection > or = 6 months post-transplantation) data from the Scientific Registry of Transplant Recipients (SRTR) were used. We studied adult primary liver transplant recipients transplanted between June 1, 1995, and April 30, 2004, with hepatitis C virus (HCV) (n = 3356), hepatitis B virus (HBV) (n = 550) or a nonviral (n = 5740) primary cause of liver disease who were recorded as receiving continuous 3-(MMF + Tacro + steroids) versus 2-drug (Tacro + steroids) therapy for at least 6 months immediately post transplantation. Kaplan-Meier analysis showed significantly lower LAR rates 4 years post-transplant in 3- versus 2-drug HCV, HBV and nonviral disease patients. Multivariate regression confirmed 3- versus 2-drug therapy to be associated with a decreased risk of LAR. Late graft survival was significantly lower at 4 years post-transplant for patients with LAR 6-12 months post-transplantation versus patients with early rejection (78.0% vs. 87.0%, p < 0.001) and no rejection (88.1%, p < 0.001). Three-drug versus 2-drug therapy for a minimum of 6 months may offer a better treatment strategy to avoid the consequences and expense of LAR episodes.  相似文献   
90.
Zusammenfassung Dieser Artikel stellt eine Übersetzung der im Jahr 2006 herausgegebenen Empfehlungen zur Behandlung von Patienten mit spontaner intrazerebraler Blutung der Europäischen Schlaganfallinitiative (EUSI) für das Europäische Schlaganfall-Council (ESC), die Europäische Neurologische Gesellschaft (ENS) und die Europäische Förderation Neurologischer Gesellschaften (EFNS) dar.Diese EUSI-Empfehlungen werden von dem European Stroke Council (ESC), der European Neurological Society (ENS) und der European Federation of Neurological Societies (EFNS) unterstützt.  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