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   5767篇
  免费   375篇
  国内免费   9篇
耳鼻咽喉   73篇
儿科学   320篇
妇产科学   77篇
基础医学   767篇
口腔科学   179篇
临床医学   399篇
内科学   1311篇
皮肤病学   109篇
神经病学   428篇
特种医学   142篇
外科学   628篇
综合类   168篇
一般理论   1篇
预防医学   377篇
眼科学   113篇
药学   426篇
中国医学   53篇
肿瘤学   580篇
  2023年   23篇
  2022年   76篇
  2021年   209篇
  2020年   99篇
  2019年   129篇
  2018年   141篇
  2017年   92篇
  2016年   121篇
  2015年   139篇
  2014年   203篇
  2013年   272篇
  2012年   425篇
  2011年   385篇
  2010年   225篇
  2009年   185篇
  2008年   263篇
  2007年   274篇
  2006年   241篇
  2005年   243篇
  2004年   221篇
  2003年   216篇
  2002年   193篇
  2001年   164篇
  2000年   170篇
  1999年   160篇
  1998年   69篇
  1997年   58篇
  1996年   40篇
  1995年   48篇
  1994年   34篇
  1993年   30篇
  1992年   104篇
  1991年   80篇
  1990年   84篇
  1989年   86篇
  1988年   70篇
  1987年   62篇
  1986年   54篇
  1985年   53篇
  1984年   49篇
  1983年   43篇
  1982年   23篇
  1981年   19篇
  1979年   39篇
  1978年   25篇
  1976年   16篇
  1974年   22篇
  1973年   22篇
  1971年   16篇
  1970年   22篇
排序方式: 共有6151条查询结果,搜索用时 15 毫秒
61.
62.
63.
Background: Laugier-Hunziker (LH) syndrome is a rare condition in which melanocyte overactivity produces lentiginous lesions of the lips and buccal mucosa. Objective: Given the paucity of reports on therapeutic options in LH syndrome, this case is herein reported to show the response to treatment with the Q-Switched Nd:YAG laser in a 32-year-old man with LH Syndrome. Methods: The Q-Switched Nd:YAG laser was used to treat the lentiginous lesions on the mucosal surface of the lower lips using a single pass at 532 nm. Results: There was complete clearance of the mucosal lentiginous lesions with a single laser session, and recurrence was not observed after 12 months. Conclusion: The Q-Switched Nd:YAG laser is an effective treatment option for cosmetic benefit in LH Syndrome.  相似文献   
64.
Between January 1980 and December 1986, 2573 patients underwent simple first time coronary artery bypass grafting, of whom 73 (65 males and 8 females) aged 34-69 years (mean 51.3 yrs) had repeat bypass grafts at Wythenshawe Hospital, Manchester. Of these 73 patients, 15 had a previous myocardial infarction, 5 hyperlipidaemia, 4 systemic hypertension, and 12 had a strong family history of ischemic heart disease. There was an overall deterioration of left ventricular function at the time of reoperation. The interval between the two operations was 5-131 months (mean 34.2 mths); recurrence of angina occurred earlier (mean 18.4 mths). Vessels grafted at the first operation were LAD (59), RCA (46), circumflex (41) and diagonal (13). The corresponding data at reoperation were LAD (55), RCA (46), circumflex (28) and diagonal (10). Blocked grafts were seen in 67 patients and new lesions noticed in 29. Reoperation was done using saphenous vein (129), internal mammary artery (5), arm veins (2) and tubular Gortex grafts (2). One patient had concurrent excision of a left ventricular aneurysm. Coronary anastomoses were performed with elective ventricular fibrillation (47) or cardioplegic arrest (91). Aortic cross clamp time varied from 0-92 minutes. Seven patients required intra-aortic balloon support. These patients died in the first 30 days, an operative mortality rate of 4.1%, and two 18 months after surgery. Sixty-eight percent of patients seen at 1 year were totally symptom free. We conclude that reoperation for coronary artery disease can be done with a low mortality and good immediate relief of symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
65.

Background

Transplantation of hearts retrieved from donation after circulatory death (DCD) donors is an evolving clinical practice.

Objectives

The purpose of this study is to provide an update on the authors’ Australian clinical program and discuss lessons learned since performing the world’s first series of distantly procured DCD heart transplants.

Methods

The authors report their experience of 23 DCD heart transplants from 45 DCD donor referrals since 2014. Donor details were collected using electronic donor records (Donate Life, Australia) and all recipient details were collected from clinical notes and electronic databases at St. Vincent’s Hospital.

Results

Hearts were retrieved from 33 of 45 DCD donors. A total of 12 donors did not progress to circulatory arrest within the pre-specified timeframe. Eight hearts failed to meet viability criteria during normothermic machine perfusion, and 2 hearts were declined due to machine malfunction. A total of 23 hearts were transplanted between July 2014 and April 2018. All recipients had successful implantation, with mechanical circulatory support utilized in 9 cases. One case requiring extracorporeal membrane oxygenation subsequently died on the sixth post-operative day, representing a mortality of 4.4% over 4 years with a total follow-up period of 15,500 days for the entire cohort. All surviving recipients had normal cardiac function on echocardiogram and no evidence of acute rejection on discharge. All surviving patients remain in New York Heart Association functional class I with normal biventricular function.

Conclusions

DCD heart transplant outcomes are excellent. Despite a higher requirement for mechanical circulatory support for delayed graft function, primarily in recipients with ventricular assist device support, overall survival and rejection episodes are comparable to outcomes from contemporary brain-dead donors.  相似文献   
66.
67.
68.
Mosca PJ  Hobeika AC  Clay TM  Nair SK  Thomas EK  Morse MA  Lyerly HK 《Blood》2000,96(10):3499-3504
Dendritic cells (DCs) may arise from multiple lineages and progress through a series of intermediate stages until fully mature, at which time they are capable of optimal antigen presentation and T-cell activation. High cell surface expression of CD83 is presumed to correlate with full maturation of DCs, and a number of agents have been shown to increase CD83 expression on DCs. We hypothesized that interleukin 12 (IL-12) expression would be a more accurate marker of functionally mature DCs capable of activating antigen-specific T cells. We used combinations of signaling through CD40, using CD40 ligand trimer (CD40L), and interferon gamma to demonstrate that CD83 expression is necessary but not sufficient for optimal production of IL-12 by DCs. Phenotypically mature DCs could be induced to produce high levels of IL-12 p70 only when provided 2 simultaneous stimulatory signals. By intracellular cytokine detection, we determined that only a subset of cells that express high levels of CD80 and CD83 generate large amounts of IL-12. DCs matured with both signals are superior to DCs stimulated with the individual agents in activating antigen-specific T cell in vitro. These findings have important implications regarding the identification, characterization, and clinical application of functionally mature DCs.  相似文献   
69.
70.
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