全文获取类型
收费全文 | 3126篇 |
免费 | 222篇 |
国内免费 | 7篇 |
专业分类
耳鼻咽喉 | 76篇 |
儿科学 | 61篇 |
妇产科学 | 82篇 |
基础医学 | 438篇 |
口腔科学 | 45篇 |
临床医学 | 339篇 |
内科学 | 562篇 |
皮肤病学 | 58篇 |
神经病学 | 270篇 |
特种医学 | 128篇 |
外科学 | 611篇 |
综合类 | 13篇 |
预防医学 | 179篇 |
眼科学 | 67篇 |
药学 | 190篇 |
肿瘤学 | 236篇 |
出版年
2022年 | 28篇 |
2021年 | 62篇 |
2020年 | 31篇 |
2019年 | 41篇 |
2018年 | 74篇 |
2017年 | 43篇 |
2016年 | 66篇 |
2015年 | 85篇 |
2014年 | 101篇 |
2013年 | 126篇 |
2012年 | 171篇 |
2011年 | 201篇 |
2010年 | 124篇 |
2009年 | 115篇 |
2008年 | 144篇 |
2007年 | 134篇 |
2006年 | 168篇 |
2005年 | 147篇 |
2004年 | 111篇 |
2003年 | 128篇 |
2002年 | 103篇 |
2001年 | 69篇 |
2000年 | 105篇 |
1999年 | 90篇 |
1998年 | 44篇 |
1997年 | 19篇 |
1996年 | 29篇 |
1995年 | 20篇 |
1994年 | 22篇 |
1993年 | 22篇 |
1992年 | 50篇 |
1991年 | 50篇 |
1990年 | 47篇 |
1989年 | 33篇 |
1988年 | 55篇 |
1987年 | 35篇 |
1986年 | 38篇 |
1985年 | 26篇 |
1984年 | 23篇 |
1983年 | 17篇 |
1982年 | 22篇 |
1980年 | 18篇 |
1979年 | 18篇 |
1978年 | 19篇 |
1977年 | 18篇 |
1975年 | 17篇 |
1973年 | 22篇 |
1972年 | 16篇 |
1970年 | 16篇 |
1968年 | 18篇 |
排序方式: 共有3355条查询结果,搜索用时 31 毫秒
1.
2.
3.
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
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
4.
Franz F Immer Urs Hagen Pascal A Berdat Friedrich S Eckstein Thierry P Carrel 《European journal of cardio-thoracic surgery》2005,27(4):654-657
OBJECTIVES: Prompt diagnosis of subsequent dilatation of the dissected aorta is crucial to reduce late mortality in these patients. This study focuses on risk factors for dilatation of the aorta after type A aortic dissection (AADA) affecting a normal-sized or slightly dilated aorta. METHODS: Overall 531 CT scans were analysed. Patients were included in the study if at least 3 CT scans were available after operative repair. 64 patients (59.8%) out of 107 patients full-field the inclusion criteria. Volumetric analyses of the aorta were performed. Patients were divided in 3 groups: group A included 26 patients (40.6%) without progression of the aortic diameter, group 2, 27 patients (42.2%) with slight progression and group 3, 11 patients (17.2%) with important progression, requiring surgery in 9 patients (81.8%). Risk-factors for progression of the aortic size were analysed and compared between the groups. RESULTS: Patients from group 3 were younger 57.7+/-13.4 vs. 61.9+/-11.6 in group 1 (P<0.05) and were more frequent female (45.4 vs. 23.1%; P<0.05). Dissection of the supraaortic branches (100 vs. 80.8%; P<0.05), the presence of preoperative cerebral, visceral or peripheral malperfusion (54.6 vs. 26.9%; P<0.05) and contrast enhancement in the false lumen during the follow-up (72.7 vs. 57.7%; P=0.07) were additional risk factors for late aortic dilatation in these patients. CONCLUSIONS: Acute type A aortic dissection in younger patients, involving the supraaortic branches and/or combined with malperfusion syndrome favour secondary dilatation. A close follow-up is mandatory to prevent acute complications of the diseased downstream aorta following repair of a AADA. 相似文献
5.
Association of polymorphonuclear leukocytes with sites of aortic catheter-induced injury in rabbits 总被引:4,自引:0,他引:4
C W Cole P O Hagen J F Lucas E M Mikat M K O'Malley Z S Radic R G Makhoul R L McCann 《Atherosclerosis》1987,67(2-3):229-236
The kinetics of the association of polymorphonuclear leukocytes (PMNs) with arterial balloon catheter-induced injury have been examined. An average of 6 X 10(7) PMNs were isolated from 20 ml of blood and labelled with 111In-oxine for reinfusion into the donor rabbit. The cells remained viable as demonstrated by both in vitro and in vivo tests of cell function. The abdominal aorta of rabbits was denuded of endothelium and immediately, 24 h, or 5 weeks later, exposed to autologous radiolabelled PMNs for 1 h. The presence of PMNs at sites of denudation was demonstrated by detection of the radioactive label and was confirmed by light and electron microscopy after 24 h, but not at 5 weeks. Immediately following denudation radioactivity was 2.44 +/- 0.33 times control (P = 0.006); 2.52 +/- 0.18 at 24 h (P = 0.005); and 1.88 +/- 0.32 times control at 5 weeks (P = 0.045). The presence of PMNs, or their products, 5 weeks after denudation suggests a more complex role of PMNs and possibly a direct involvement in the long term changes resulting from arterial balloon catheter injury. 相似文献
6.
Dysphagia was studied in 29 patients after implantation of an Angelchik prosthesis for persistent reflux oesophagitis. The incidence of postoperative dysphagia occurred after three months (61%), six months (45%), and one year or more (41%). Severe dysphagia necessitated removal of the prosthesis in five patients (17%). The reoperative findings with regard to a possible explanation of dysphagia are discussed, and comparison is made with reports in literature. Implantation of the Angelchik prosthesis seems only indicated for the treatment of intractable reflux oesophagitis in patients where other operative modalities failed and who are at high risk for operation. The Nissen fundoplication remains the operation of choice. 相似文献
7.
The synthesis of the title compounds starting from 2-Chlormethylbenzdioxan and Tetrahydroisochinolines is presented. Their actions on the platelet aggregation and the inhibition of alpha-adrenoceptors at the isolated rabbit aorta and the vas deferens of the guinea pig were investigated. 相似文献
8.
Ohne Zusammenfassung 相似文献
9.
Abstract Simultaneous bilateral avulsions of the tibial tuberosity are rare injuries. The authors found only five reported cases in
the orthopedic literature. We add a further case of bilateral avulsions of the tibial tuberosity with the longest reported
follow-up. 相似文献
10.
L. J. Stovner J.-A. Zwart K. Hagen G. M. Terwindt J. Pascual 《European journal of neurology》2006,13(4):333-345
The present review of epidemiologic studies on migraine and headache in Europe is part of a larger initiative by the European Brain Council to estimate the costs incurred because of brain disorders. Summarizing the data on 1-year prevalence, the proportion of adults in Europe reporting headache was 51%, migraine 14%, and 'chronic headache' (i.e. > or =15 days/month or 'daily') 4%. Generally, migraine, and to a lesser degree headache, are most prevalent during the most productive years of adulthood, from age 20 to 50 years. Several European studies document the negative influence of headache disorders on the quality of life, and health-economic studies indicate that 15% of adults were absent from work during the last year because of headache. Very few studies have been performed in Eastern Europe, and there are also surprisingly little data on tension-type headache from any country. Although the methodology and the quality of the published studies vary considerably, making direct comparisons between different countries difficult, the present review clearly demonstrates that headache disorders are extremely prevalent and have a vast impact on public health. The data collected should be used as arguments to increase resources to headache research and care for headache patients all over the continent. 相似文献