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   1427731篇
  免费   94670篇
  国内免费   2908篇
耳鼻咽喉   20396篇
儿科学   43431篇
妇产科学   40014篇
基础医学   198801篇
口腔科学   40328篇
临床医学   118209篇
内科学   280537篇
皮肤病学   30634篇
神经病学   115585篇
特种医学   57605篇
外国民族医学   435篇
外科学   223852篇
综合类   31867篇
现状与发展   6篇
一般理论   436篇
预防医学   100375篇
眼科学   32265篇
药学   105203篇
  4篇
中国医学   2993篇
肿瘤学   82333篇
  2018年   22543篇
  2017年   18350篇
  2016年   20810篇
  2015年   12246篇
  2014年   16976篇
  2013年   25507篇
  2012年   35906篇
  2011年   44346篇
  2010年   28331篇
  2009年   25777篇
  2008年   43386篇
  2007年   48761篇
  2006年   37468篇
  2005年   38059篇
  2004年   37482篇
  2003年   37570篇
  2002年   35859篇
  2001年   63896篇
  2000年   65781篇
  1999年   55567篇
  1998年   14824篇
  1997年   13685篇
  1996年   13082篇
  1995年   12369篇
  1994年   11630篇
  1992年   42880篇
  1991年   41402篇
  1990年   40679篇
  1989年   39652篇
  1988年   37058篇
  1987年   36511篇
  1986年   34992篇
  1985年   33202篇
  1984年   24882篇
  1983年   21113篇
  1982年   12745篇
  1981年   11583篇
  1979年   23997篇
  1978年   17124篇
  1977年   14844篇
  1976年   13443篇
  1975年   15268篇
  1974年   18104篇
  1973年   17568篇
  1972年   16810篇
  1971年   15717篇
  1970年   14944篇
  1969年   14382篇
  1968年   13482篇
  1967年   12015篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
993.
We report a successful endovascular stent-graft treatment of a patient with type A dissection with primary entry tear at the ascending aorta. Simultaneous coronary stenting was performed. A literature review was performed and the possible use of endovascular treatment for ascending aortic dissections is discussed.  相似文献   
994.
995.
Spinal cord stimulation (SCS) involves the use of an epidurally placed, multiple electrode lead. Electrical stimulation between electrodes produces stimulation of the posterior spinal cord and can provide excellent pain relief and increased blood flow in a number of chronic limb pain conditions. Its efficacy has more recently been demonstrated in angina. Chronic stable angina pectoris is a major cause of disability and suffering. The aims of treatment are to prevent MI and death (increase the quantity of life) and reduce the symptoms (improve the quality of life). In the non‐acute condition, practitioners often struggle to manage angina because of a lack of understanding of modern concepts of pain. There is a widely held misconception that only revascularisation improves prognosis in chronic refractory angina‐ the term used to describe patients with stable angina that is treatment refractory. Over the last decade two pain services in New Zealand have been approached by cardiologists to provide spinal cord stimulation for such patients. This has been an intriguing experience! We have demonstrated that the placement of such leads in the lower cervical cord region provides excellent relief of angina. The technology is expensive (akin to the overall cost of CAVG surgery). We have demonstrated cost recoupment, by decreased hospitalisation, at approximately16 months post procedure. Sadly, this therapy has not been embraced. Possible reasons for this will be discussed. The concept of electrically modifying the neuronal signals versus re‐plumbing the blockage appears to be an anathema to cardiologists.  相似文献   
996.
997.
BACKGROUND: Clinical benefit from extended lymphadenectomy for gastric cancer remains controversial as a considerable variation exists between results of different studies. METHODS: 562 patients were treated at HUCH between 1987-2003, whereof 223 underwent gastrectomy with curative intent. Of these, 114 patients underwent subtotal/total gastrectomy with D1 (standard) lymphadenectomy and 109 patients had D2-3 (extended) lymph node dissection. The clinical outcome of these patients was analysed retrospectively. RESULTS: The incidence of surgical complications was 33.0% in D2-3 and 16.8% in D1 lymphadenectomy groups (p = 0.008). Abscess was the most common complication (11.0%) among D2-3 operated patients and haemorrhage (4.4%) in D1 group. Hospital mortality was 3.7% in D2-3 and 1.8% in D1 group (p = 0.438). The only statistically significant factor influencing the rate of complications was D2-3 lymphadenectomy (OR 2.620, 95% C.I. 1.375 to 4.991). D2-3 was associated with a longer postoperative hospital stay and operation time, greater blood loss and increased need for blood transfusions compared to D1. The 5-year survival was not statistically different between lymphadenectomy groups. CONCLUSION: It is justified to perform a D2-3 gastrectomy in Europe with a acceptable postoperative mortality but with a significant morbidity. Further studies are needed to assess the value of extended lymphadenectomy in gastric cancer.  相似文献   
998.
We report a case of an intra-articular vascular malformation occurring simultaneously with a ganglion in a knee joint. We believe this to be the first reported case of an intra-articular vascular malformation occurring simultaneously with a ganglion. The malformation was cauterized resulting in resolution of knee pain. We suggest that vascular malformations be considered in the differential diagnosis of knee pain.  相似文献   
999.
Efficacy and safety of mycophenolate mofetil (MMF) may be optimized with individualized doses based on therapeutic monitoring of its active metabolite, mycophenolic acid (MPA). In this 12-month study, 137 renal allograft recipients from 11 French centers receiving basiliximab, cyclosporine A, MMF and corticosteroids were randomized to receive either concentration-controlled doses or fixed-dose MMF. A novel Bayesian estimator of MPA AUC based on three-point sampling was used to individualize doses on posttransplant days 7 and 14 and months 1, 3 and 6. The primary endpoint was treatment failure (death, graft loss, acute rejection and MMF discontinuation). Data from 65 patients/group were analyzed. At month 12, the concentration-controlled group had fewer treatment failures (p = 0.03) and acute rejection episodes (p = 0.01) with no differences in adverse event frequency. The MMF dose was higher in the concentration-controlled group at day 14 (p < 0.0001), month 1 (p < 0.0001) and month 3 (p < 0.01), as were median AUCs on day 14 (33.7 vs. 27.1 mg*h/L; p = 0.0001) and at month 1 (45.0 vs. 30.9 mg*h/L; p < 0.0001). Therapeutic MPA monitoring using a limited sampling strategy can reduce the risk of treatment failure and acute rejection in renal allograft recipients 12 months posttransplant with no increase in adverse events.  相似文献   
1000.
OBJECTIVES: To present a single centers' 7-year experience in the endovascular treatment of acute traumatic lesions of the descending thoracic aorta (ATL of the DTA). MATERIALS & METHODS: Between March 1999 and December 2006, 34 consecutive acute traumatic lesions of the descending aorta (23 men, mean age 44 years) were treated endovascularly. Stentgrafts used were TAG Excluder, Zenith TX2 and Talent. In 23 patients the Left Subclavian Artery (LSA) was covered. Mean procedural duration was 20 to 75 minutes. RESULTS: Exclusion of the rupture site was achieved in all cases with no conversion to open surgery. Overall 30-day mortality was 8.8%. Two patients died on post operative day (pod) 1 and one on pod 22 from cranial injuries. No death or neurological deficit related to the endovascular treatment was reported. Four type I endoleaks required treatment either by balloon reexpansion (n=2) or by additional stentgraft implantation (n=2). In two patients the stentgraft collapsed totally several days postoperatively. Two patients required secondary surgical procedures (iliac access complication and revascularisation of the left subclavian artery n=1). The average follow-up was 43.8 months (1-93 months). No stentgraft related abnormality has been subsequently documented. CONCLUSIONS: The endovascular treatment of ATL of the DTA may offer the best means of therapy in a polytrauma patient.  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