全文获取类型
收费全文 | 2519607篇 |
免费 | 175642篇 |
国内免费 | 3808篇 |
专业分类
耳鼻咽喉 | 34369篇 |
儿科学 | 82496篇 |
妇产科学 | 67866篇 |
基础医学 | 369691篇 |
口腔科学 | 68335篇 |
临床医学 | 227330篇 |
内科学 | 486376篇 |
皮肤病学 | 55321篇 |
神经病学 | 196722篇 |
特种医学 | 96823篇 |
外国民族医学 | 578篇 |
外科学 | 376901篇 |
综合类 | 48702篇 |
现状与发展 | 12篇 |
一般理论 | 893篇 |
预防医学 | 198983篇 |
眼科学 | 57864篇 |
药学 | 186827篇 |
12篇 | |
中国医学 | 4700篇 |
肿瘤学 | 138256篇 |
出版年
2021年 | 19639篇 |
2019年 | 20258篇 |
2018年 | 30837篇 |
2017年 | 24224篇 |
2016年 | 26028篇 |
2015年 | 30389篇 |
2014年 | 40580篇 |
2013年 | 58300篇 |
2012年 | 84915篇 |
2011年 | 85479篇 |
2010年 | 50089篇 |
2009年 | 48805篇 |
2008年 | 78188篇 |
2007年 | 83650篇 |
2006年 | 84658篇 |
2005年 | 88947篇 |
2004年 | 86893篇 |
2003年 | 80059篇 |
2002年 | 73644篇 |
2001年 | 111387篇 |
2000年 | 112610篇 |
1999年 | 96908篇 |
1998年 | 27690篇 |
1997年 | 24069篇 |
1996年 | 24460篇 |
1995年 | 23106篇 |
1994年 | 21267篇 |
1993年 | 20049篇 |
1992年 | 76196篇 |
1991年 | 74477篇 |
1990年 | 72972篇 |
1989年 | 70059篇 |
1988年 | 64459篇 |
1987年 | 63113篇 |
1986年 | 59120篇 |
1985年 | 56429篇 |
1984年 | 41694篇 |
1983年 | 35368篇 |
1982年 | 20587篇 |
1979年 | 38531篇 |
1978年 | 27307篇 |
1977年 | 22527篇 |
1976年 | 21401篇 |
1975年 | 23560篇 |
1974年 | 28322篇 |
1973年 | 26758篇 |
1972年 | 25182篇 |
1971年 | 24038篇 |
1970年 | 22084篇 |
1969年 | 21052篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
Summary A new modification of microvenous anastomosis, which has increased patency rates while simultaneously decreasing the difficulty of the procedure, is presented in this paper. The primary purpose of this study was to compare the classical and the temporary stent techniques of microvenous anastomosis. Because of problems such as mixing and tangling of strings during insertion and tying of the last four sutures while applying the temporary stent technique, we decided to modify the procedure. The silastic tube was removed through an incision (venotomy), distant from the actual suture line. This modified technique and the other above mentioned techniques were carried out on rat femoral veins. The results indicate that this modification has increased patency rates, shortened the time of anastomosis and facilitated the procedure. 相似文献
992.
993.
Responses to tuberculin in the guinea-pig eye as a model of cell mediated immune responses in the external eye.
下载免费PDF全文
![点击此处可从《The British journal of ophthalmology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
The clinical and histological findings in an animal model of ocular cell mediated immune responses are described. These were evoked in sensitised guinea-pigs by dropping tuberculin into the conjunctival sac or injecting it under the palpebral conjunctiva. When tuberculin was dropped into the conjunctival sac, higher doses were required to evoke a strong response than when it was injected subconjunctivally. When high doses of antigen were used for challenge, a mild response was observed in unchallenged contralateral eyes. The cellular response at low doses of tuberculin consisted predominantly of mononuclear cells. At higher doses the cellular infiltrate was more pronounced, and polymorphonuclear cells tended to predominate 24 hours after challenge, while at 48 hours mononuclear cells predominated. 相似文献
994.
R A Mustard J M Bohnen S Haseeb R Kasina 《Archives of surgery (Chicago, Ill. : 1960)》1987,122(1):69-73
We studied 108 patients undergoing clean-contaminated and dirty surgical procedures to determine whether daily C-reactive protein (CRP) measurements for 14 days postoperatively could predict the occurrence of septic complications prior to clinical diagnosis. Diagnostic criteria for septic complications and positive CRP response were defined in advance of the study. The CRP assays were carried out using an automated laser nephelometer system after the patient's discharge from the hospital. Forty-six septic complications were diagnosed in 40 patients. These complications consisted of wound infection (23), urinary tract infection (11), pneumonia (six), upper respiratory tract infection (three), intra-abdominal abscess (one), and other (two). The CRP testing was found to have a positive predictive value of 69% and a negative predictive value of 78%. We conclude that serial CRP measurements may be a valuable adjunct to surgical care in patients at high risk of postoperative septic complications. 相似文献
995.
C.T. PEASE M. FENNELL R.C.D. STAUGHTON D.A. BREWERTON 《The British journal of dermatology》1987,117(2):161-167
Polymorphonuclear leukocyte (PMN) migration was assessed in vitro using the agarose plate method in patients with psoriasis vulgaris, and compared with an age- and sex-matched control group. No significant difference was found between the two groups in the PMN response to the chemotactic substances F-Met-Leu-Phe (FMLP) or zymosan activated serum (ZAS). Equally, the chemokinetic or chemotactic potential of psoriatic serum did not differ from control serum. Our results do not support a primary abnormality of PMN function in psoriasis. 相似文献
996.
A national alcohol and trauma center survey. Missed opportunities, failures of responsibility 总被引:4,自引:0,他引:4
The results of a national survey of trauma centers concerning their assessment and response to the problem of alcohol and trauma are reported. Surveys were returned from 154 trauma centers located in 43 states and the District of Columbia. The profile of the 125,000 patients treated at the centers is a 30-year-old man sustaining blunt trauma, usually in a vehicular crash. Two-thirds of centers estimated that the majority of their patients had abused alcohol. While acknowledging alcohol as a significant cause of trauma, only 55.2% of centers routinely obtain admitting blood alcohol levels. Less than a third of the centers employ alcoholism counselors. Most trauma centers are not providing services that allow them to fulfill their responsibility to detect and initiate treatment of alcohol abuse, a major cause of traumatic injury. 相似文献
997.
Inhibition of vessel allograft rejection by endothelial removal. Morphologic and ultrastructural changes. 总被引:1,自引:1,他引:0
下载免费PDF全文
![点击此处可从《Annals of surgery》网站下载免费的PDF全文](/ch/ext_images/free.gif)
M A Galumbeck F P Sanfilippo P O Hagen A V Seaber J R Urbaniak 《Annals of surgery》1987,206(6):757-764
The vascular endothelium plays an important and complex role in vascular allograft rejection. Antigens expressed by the endothelium can act to promote and be the target of rejection reactions, which often lead to thrombosis and ischemic necrosis of the allograft. In this study, segments of femoral artery and femoral vein with or without endothelium were grafted between allogenic or autologous control rats. Immunocompetent Lewis (RT1(1] recipient rats were randomly selected for groups (N = 14 for each) receiving the following: ACI- (RT1a) allografts with intact endothelium, allografts with endothelium removed before operation, autografts with endothelium, and autografts with endothelium removed. Rejection was assessed by graft patency as well as morphologic and ultrastructural changes. At 5 days, the allografts with intact endothelium were totally occluded, whereas allografts without endothelium remained patent, as did autologous control grafts with or without endothelium. Two additional groups (N = 14 each) receiving the de-endothelialized allografts or autografts were examined at 120 days after operation, revealing that grafts in both groups were still patent and had been re-endothelialized. These findings indicate that physical removal of vascular endothelium may depress vessel allograft rejection without immunosuppressive therapy. 相似文献
998.
999.
1000.