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   3381659篇
  免费   239089篇
  国内免费   8792篇
耳鼻咽喉   46865篇
儿科学   112191篇
妇产科学   94934篇
基础医学   478219篇
口腔科学   94454篇
临床医学   303990篇
内科学   660459篇
皮肤病学   79136篇
神经病学   273824篇
特种医学   130877篇
外国民族医学   1047篇
外科学   510095篇
综合类   69460篇
现状与发展   6篇
一般理论   1192篇
预防医学   258128篇
眼科学   76922篇
药学   249400篇
  9篇
中国医学   6797篇
肿瘤学   181535篇
  2018年   36127篇
  2017年   27607篇
  2016年   31944篇
  2015年   36102篇
  2014年   49729篇
  2013年   75082篇
  2012年   100023篇
  2011年   106180篇
  2010年   63950篇
  2009年   61153篇
  2008年   99900篇
  2007年   106592篇
  2006年   108574篇
  2005年   104476篇
  2004年   100655篇
  2003年   97432篇
  2002年   94566篇
  2001年   158021篇
  2000年   161947篇
  1999年   136933篇
  1998年   39745篇
  1997年   35254篇
  1996年   35508篇
  1995年   34174篇
  1994年   31628篇
  1993年   29670篇
  1992年   108012篇
  1991年   104686篇
  1990年   101930篇
  1989年   98771篇
  1988年   90974篇
  1987年   89321篇
  1986年   84272篇
  1985年   80536篇
  1984年   59834篇
  1983年   51377篇
  1982年   30603篇
  1981年   27183篇
  1979年   54262篇
  1978年   38297篇
  1977年   32826篇
  1976年   30583篇
  1975年   33006篇
  1974年   38864篇
  1973年   37098篇
  1972年   35175篇
  1971年   32576篇
  1970年   30394篇
  1969年   29177篇
  1968年   27048篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
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   
42.
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   
43.
44.
45.
46.
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   
47.
48.
49.
The value of adding simeprevir (SMV) vs placebo (PBO) to peginterferon and ribavirin (PR) for treatment of chronic hepatitis C virus infection was examined using patient‐reported outcomes (PROs); further, concordance of PROs with virology endpoints and adverse events (AEs) was explored. Patients (= 768 SMV/PR,= 393 PBO/PR) rated fatigue (FSS), depressive symptoms (CES‐D) and functional impairment (WPAI: Hepatitis C Productivity, Daily Activity and Absenteeism) at baseline and throughout treatment in three randomised, double‐blind trials comparing the addition of SMV or PBO during initial 12 weeks of PR. PR was administered for 48 weeks (PBO group) and 24/48 weeks (SMV group) using a response‐guided therapy (RGT) approach. Mean PRO scores (except Absenteeism) worsened from baseline to Week 4 to the same extent in both groups but reverted after Week 24 for SMV/PR and only after Week 48 for PBO/PR. Accordingly, there was a significantly lower area under the curve (baseline–Week 60, AUC60) and fewer weeks with clinically important worsening of scores in the SMV/PR group at any time point. Incidences of patients with fatigue and anaemia AEs were similar in both groups, but FSS scores showed that clinically important increases in fatigue lasted a mean of 6.9 weeks longer with PBO/PR (P < 0.001). PRO score subgroup analysis indicated better outcomes for patients who met the criteria for RGT or achieved sustained virological response 12 weeks post‐treatment (SVR12); differences in mean PRO scores associated with fibrosis level were only observed with PBO/PR. Greater efficacy of SMV/PR enabled reduced treatment duration and reduced time with PR‐related AEs without adding to AE severity.  相似文献   
50.
Platelet transfusions are a life-saving medical intervention used for the treatment of thrombocytopenia or hemorrhage. Extensive research has gone into trying to understand how to store platelets prior to the transfusion event. Much has been learned about storage bag materials, synthetic solutions, and how temperature impacts platelet viability and function. While room temperature storage of platelets preserves 24-hour in vivo platelet recovery and survival there is a greater risk for bacterial growth. Therefore, cold storage of platelets has become attractive due to the reduction in potential bacterial proliferation and the maintenance of platelet function beyond 5 days of storage. Cold stored platelets, however, have their own set of challenges. Cold stored platelets become activated through several mechanisms. The morphological and molecular changes that occur due to cold exposure enhance their ability to participate in the hemostatic process at the cost of rapid clearance from circulation. This review focuses on the underlying mechanisms leading to cold platelet activation and the receptor modifications involved in platelet clearance.  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