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   4073767篇
  免费   300975篇
  国内免费   10213篇
耳鼻咽喉   57489篇
儿科学   130397篇
妇产科学   111147篇
基础医学   568594篇
口腔科学   116953篇
临床医学   375367篇
内科学   789409篇
皮肤病学   91249篇
神经病学   338068篇
特种医学   158615篇
外国民族医学   1438篇
外科学   610096篇
综合类   91199篇
现状与发展   6篇
一般理论   1721篇
预防医学   325437篇
眼科学   94696篇
药学   301358篇
  11篇
中国医学   7981篇
肿瘤学   213724篇
  2018年   43693篇
  2017年   33602篇
  2016年   38176篇
  2015年   43078篇
  2014年   60654篇
  2013年   92097篇
  2012年   122379篇
  2011年   129871篇
  2010年   77874篇
  2009年   74455篇
  2008年   121875篇
  2007年   129490篇
  2006年   131232篇
  2005年   126865篇
  2004年   122253篇
  2003年   117865篇
  2002年   114692篇
  2001年   187081篇
  2000年   192579篇
  1999年   163323篇
  1998年   48498篇
  1997年   43287篇
  1996年   42914篇
  1995年   41626篇
  1994年   38649篇
  1993年   36160篇
  1992年   129765篇
  1991年   125539篇
  1990年   121345篇
  1989年   117250篇
  1988年   108368篇
  1987年   106756篇
  1986年   100826篇
  1985年   96581篇
  1984年   72643篇
  1983年   62036篇
  1982年   37362篇
  1981年   33619篇
  1979年   66754篇
  1978年   47241篇
  1977年   40029篇
  1976年   37498篇
  1975年   39600篇
  1974年   47998篇
  1973年   45814篇
  1972年   43108篇
  1971年   39926篇
  1970年   37307篇
  1969年   35278篇
  1968年   32451篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
42.
Interstitial cystitis/bladder pain syndrome (IC/BPS) and vulvodynia are chronic pain syndromes that appear to be intertwined from the perspectives of embryology, pathology and epidemiology. These associations may account for similar responses to various therapies.  相似文献   
43.
Antibody-mediated rejection is a major complication in renal transplantation. The pathologic manifestations of acute antibody-mediated rejection that has progressed to functional impairment of a renal transplant have been defined in clinical biopsy specimens. However, the initial stages of the process are difficult to resolve with the unavoidable variables of clinical studies. We devised a model of renal transplantation to elucidate the initial stages of humoral rejection. Kidneys were orthotopically allografted to immunodeficient mice. After perioperative inflammation subsided, donor-specific alloantibodies were passively transferred to the recipient. Within 1 hour after a single transfer of antibodies, C4d was deposited diffusely on capillaries, and von Willebrand factor released from endothelial cells coated intravascular platelet aggregates. Platelet-transported inflammatory mediators platelet factor 4 and serotonin accumulated in the graft at 100- to 1000-fold higher concentrations compared with other platelet-transported chemokines. Activated platelets that expressed P-selectin attached to vascular endothelium and macrophages. These intragraft inflammatory changes were accompanied by evidence of acute endothelial injury. Repeated transfers of alloantibodies over 1 week sustained high levels of platelet factor 4 and serotonin. Platelet depletion decreased platelet mediators and altered the accumulation of macrophages. These data indicate that platelets augment early inflammation in response to donor-specific antibodies and that platelet-derived mediators may be markers of evolving alloantibody responses.  相似文献   
44.
45.
46.
Red cell exchange (RCE) is a common procedure in adults with sickle cell disease (SCD). Implantable dual lumen Vortex (DLV) ports can be used for RCE in patients with poor peripheral venous access. We performed a retrospective cohort study of RCE procedures performed in adults with SCD. The main objective of the study was to compare the inlet speed, duration of procedures and rate of complications performed through DLV ports to those performed through temporary central venous and peripheral catheters. Twenty‐nine adults with SCD underwent a total of 318 RCE procedures. Twenty adults had DLV ports placed and 218 procedures were performed using DLV ports. Mean length of follow‐up after DLV port placement was 397 ± 263 days. Six DLV ports were removed due to infection and 1 for malfunction after a mean of 171 ± 120 days. Compared to temporary central venous and peripheral catheters, DLV port procedures had a greater rate of procedural complications, a longer duration, and a lower inlet speed (all P < 0.01). When accounting for the maximum allowable inlet speed to avoid citrate toxicity, 40% of DLV port procedures were greater than 10% below maximum speed, compared to 7 and 14% of procedures performed through temporary central venous and peripheral catheters (P < 0.0001). In conclusion, DLV ports can be used for RCE in adults with SCD, albeit with more procedural complications and longer duration. The smaller internal diameter and longer catheter of DLV ports compared to temporary central venous catheters likely accounts for the differences noted. J. Clin. Apheresis 30:353–358, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
47.
48.
49.
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   
50.
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