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   3451260篇
  免费   247998篇
  国内免费   6135篇
耳鼻咽喉   47027篇
儿科学   112645篇
妇产科学   94014篇
基础医学   498813篇
口腔科学   98301篇
临床医学   313707篇
内科学   664395篇
皮肤病学   77037篇
神经病学   272394篇
特种医学   129171篇
外国民族医学   693篇
外科学   518362篇
综合类   76027篇
现状与发展   14篇
一般理论   1255篇
预防医学   267452篇
眼科学   82722篇
药学   254821篇
  13篇
中国医学   7545篇
肿瘤学   188985篇
  2021年   26898篇
  2019年   27782篇
  2018年   39066篇
  2017年   29480篇
  2016年   32933篇
  2015年   37190篇
  2014年   52409篇
  2013年   78205篇
  2012年   107879篇
  2011年   114350篇
  2010年   68230篇
  2009年   64002篇
  2008年   106779篇
  2007年   113782篇
  2006年   115046篇
  2005年   111032篇
  2004年   106802篇
  2003年   102384篇
  2002年   98839篇
  2001年   163010篇
  2000年   167345篇
  1999年   140352篇
  1998年   39864篇
  1997年   34853篇
  1996年   35045篇
  1995年   33249篇
  1994年   30572篇
  1993年   28583篇
  1992年   108244篇
  1991年   105205篇
  1990年   101943篇
  1989年   98361篇
  1988年   90198篇
  1987年   88288篇
  1986年   83050篇
  1985年   79484篇
  1984年   59012篇
  1983年   50283篇
  1982年   29365篇
  1979年   53684篇
  1978年   37852篇
  1977年   31787篇
  1976年   30144篇
  1975年   32054篇
  1974年   38828篇
  1973年   37183篇
  1972年   34712篇
  1971年   32632篇
  1970年   30277篇
  1969年   28628篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
181.
目的:确定UVB靶向光疗治疗局限性银屑病是否安全有效及是否存在量效关系。设计:随机、对评估者设盲对照研究。机构:泰国曼谷大学医院皮肤病门诊。患者:14例稳定性局限性斑块型银屑病患者。干预:依据预定的最小红斑量(M EDs),随机给予患者不同通量的UVB靶向光线治疗,3次/周。在4  相似文献   
182.
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   
183.
184.
185.
Traumatic injuries of the elbow are frequent in patients of all ages but are particularly common in young children and adolescents engaged in normal play and athletic competition. Injury may result primarily due to direct trauma or may be secondary to transmission of forces through the elbow following a fall on an outstretched hand. In middle-aged and older individuals, chronic repetitive injuries tend to predominate. In all patients, radiographs remain the initial imaging study of choice. Many patients, however, may need advanced cross-sectional imaging (i.e. MRI, CT, or ultrasound) either at presentation or during the course of their treatment and follow-up. This article reviews the imaging appearance of common acute and chronic traumatic disorders of the elbow.  相似文献   
186.
187.
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   
188.
189.
190.
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