全文获取类型
收费全文 | 40020篇 |
免费 | 2241篇 |
国内免费 | 907篇 |
专业分类
耳鼻咽喉 | 130篇 |
儿科学 | 381篇 |
妇产科学 | 382篇 |
基础医学 | 3734篇 |
口腔科学 | 2317篇 |
临床医学 | 4870篇 |
内科学 | 4095篇 |
皮肤病学 | 126篇 |
神经病学 | 575篇 |
特种医学 | 3024篇 |
外科学 | 13562篇 |
综合类 | 4855篇 |
现状与发展 | 1篇 |
预防医学 | 1350篇 |
眼科学 | 67篇 |
药学 | 1775篇 |
40篇 | |
中国医学 | 1431篇 |
肿瘤学 | 453篇 |
出版年
2024年 | 137篇 |
2023年 | 828篇 |
2022年 | 1738篇 |
2021年 | 2329篇 |
2020年 | 2168篇 |
2019年 | 1852篇 |
2018年 | 1846篇 |
2017年 | 1525篇 |
2016年 | 1404篇 |
2015年 | 1381篇 |
2014年 | 2982篇 |
2013年 | 3113篇 |
2012年 | 2092篇 |
2011年 | 2338篇 |
2010年 | 1929篇 |
2009年 | 1891篇 |
2008年 | 1772篇 |
2007年 | 1670篇 |
2006年 | 1534篇 |
2005年 | 1258篇 |
2004年 | 1204篇 |
2003年 | 924篇 |
2002年 | 776篇 |
2001年 | 638篇 |
2000年 | 540篇 |
1999年 | 459篇 |
1998年 | 385篇 |
1997年 | 343篇 |
1996年 | 274篇 |
1995年 | 255篇 |
1994年 | 204篇 |
1993年 | 196篇 |
1992年 | 167篇 |
1991年 | 92篇 |
1990年 | 97篇 |
1989年 | 88篇 |
1988年 | 108篇 |
1987年 | 94篇 |
1986年 | 67篇 |
1985年 | 65篇 |
1984年 | 65篇 |
1983年 | 57篇 |
1982年 | 64篇 |
1981年 | 44篇 |
1980年 | 35篇 |
1979年 | 40篇 |
1978年 | 25篇 |
1977年 | 22篇 |
1976年 | 21篇 |
1975年 | 15篇 |
排序方式: 共有10000条查询结果,搜索用时 10 毫秒
41.
微创内固定系统在膝关节周围复杂骨折治疗中的应用 总被引:3,自引:1,他引:2
目的探讨AO微创内固定系统(less invasive stab ilization system,LISS)治疗膝关节周围复杂骨折的效果。方法2004年4月~2005年6月对15例干骺端闭合性膝关节周围复杂骨折(左侧9例,右侧6例),分别应用股骨远端LISS或胫骨近端LISS行内固定治疗。结果15例随访5~26个月,平均13.2月。完全负重时间为12~26周,X线骨愈合时间11~24周,无延迟愈合及骨不连。浅表感染1例,皮肤水疱2例,经换药后愈合。无深部感染及皮肤坏死,无骨筋膜室综合征。Johner-W ruhs方法评价功能优11例、良3例、中1例,以优良为满意标准,本组满意率为93.3%(14/15)。1例C3型胫骨平台骨折在术后2周出现胫骨内侧骨块明显移位伴髁间分离,二次手术在胫骨平台内侧加以支撑钢板固定,术后20周骨折愈合,功能评价为良;1例C3型胫骨平台骨折在术后8周出现膝内翻(胫骨平台内翻角为82°),术后20周骨折愈合,功能评价为中。结论LISS适用于单处股骨远端、胫骨近端骨折及骨质疏松性股骨干远端骨折的治疗;对于胫骨平台C3型骨折内侧平台粉碎严重时,不能过分依赖LISS系统,或将接骨板置于内侧,而应该考虑在内侧辅助支撑钢板。 相似文献
42.
A literature review of autograft and allograft anterior cruciate ligament reconstruction 总被引:3,自引:0,他引:3
Jonathan Marrale Matthew C. Morrissey Fares S. Haddad 《Knee surgery, sports traumatology, arthroscopy》2007,15(6):690-704
Knee anterior cruciate ligament reconstructive surgery has significantly evolved and now includes the option of using an allograft.
This has resulted in numerous studies evaluating the advantages and disadvantages of allografts. The purpose of this literature
review is to evaluate this research and present important findings to allow the selection of the most appropriate graft source
when considering allograft versus autograft reconstruction. 相似文献
43.
44.
Yoshie Ochiai Kazuhiro Kurisu Takashi Kajiwara Hiroshi Kumeda Ryuji Tominaga 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2004,52(2):81-83
We describe a case of type B aortic dissection with large ascending aortic aneurysm occurring 12.8 years after aortic root
replacement (Cabrol procedure) in a non-Marfan patient with cystic medial necrosis of the aorta. We have successfully performed
an extended total aortic arch replacement using a four-branched graft through the “L-indsion” approach (a combination of a
left anterior thoracotomy and upper half median sternotomy). Of note, a histological specimen from the aneurysmal ascending
aortic wall revealed “healed aortic dissection” with fibrous tissue replacing the media and intima in addition to multiple
foci of cystic medial necrosis. 相似文献
45.
Andrew Edwards Anthony M. J. Bull Andrew A. Amis 《Knee surgery, sports traumatology, arthroscopy》2007,15(12):1414-1421
The tibial attachments of the individual anteromedial (AM) and posterolateral (PL) fibre bundles and the entire attachment
of the anterior cruciate ligament are described, relating them to consistent bony landmarks; 55 fresh-frozen specimens were
measured. The fibre bundles were separated and excised at their attachments and their peripheries marked with a pen. High-resolution
scaled digital photographs were taken of each dissected specimen and transferred onto a computer for analysis. A wide variation
was found when using the posterior tibial axis, the anterior tibial surface and the medial tibial spine as reference points.
The most consistent measurements used the tibial interspinous “over-the-back” ridge as a datum. The attachments of the PL
and AM bundles were centred 10 ± 1 mm (mean ± SD) and 17 ± 2 mm anterior to the over-the-back ridge. They were 4 ± 1 and 5 ± 1 mm,
respectively, lateral to the medial tibial spine border. The positions of 6 mm circles in the posterior-medial limits of the
fibre bundles (representing tunnels in a double-tunnel reconstruction) were measured. The overall dimensions of the tibial
plateaux correlated significantly with many measurements. The results from this study could be used to guide ACL reconstruction
techniques. 相似文献
46.
Yukihisa Fukuda Savio L-Y Woo John C Loh Eiichi Tsuda Peter Tang Patrick J McMahon Richard E Debski 《Journal of orthopaedic research》2003,21(6):1107-1112
The loads needed to elicit a positive pivot shift test in a knee with an anterior cruciate ligament (ACL) rupture have not been quantified. The coupled anterior tibial translation (ATT), coupled internal tibial rotation (ITR), and the in situ force in the ACL in response to a valgus torque, an inherent component of the pivot shift test, were measured in 10 human cadaveric knee specimens. Using a robotic/universal force-moment sensor testing system, valgus torques ranging from 0.0 to 10.0 Nm were applied in nine increments on the intact and ACL-deficient knee in flexion ranging from 0 degrees to 90 degrees. At 15 degrees of knee flexion, the coupled ATT and ITR were significantly increased in the ACL-deficient knee when compared to the intact knee. Coupled ATT increased a maximum of 291% (6.7 mm, p<0.05), while coupled ITR increased a maximum of 85% (5.1 degrees, p<0.05). At 30 degrees, the increases in coupled ATT and ITR were significant at valgus loads of 3.3 Nm and greater with a maximum increase in coupled ATT of 137% (6.3 mm, p<0.05) and a maximum increase in coupled ITR of 38% (3.6 degrees, p<0.05). At 45 degrees, coupled ATT increased significantly (maximum of 69%, 4.4 mm, p<0.05), but only at torques > or =6.7 Nm. The in situ force in the ACL was less than 20 N for all flexion angles when a torque between 3.3 and 5.0 Nm was applied. Low valgus torque elicited tibial subluxation in the ACL-deficient knee with low in situ ACL forces, similar to a positive pivot shift test. Thus, application of a valgus torque may be suitable to evaluate ACL-deficient and ACL-reconstructed knees, since subluxation can be achieved with minimal harm to the ACL graft. This work is important in understanding one load component needed for the pivot shift examination; further studies quantifying other load components are essential for better comprehension of the in vivo pivot shift examination. 相似文献
47.
48.
Tsutomu Saito Hiroyuki Horimi Tsuguo Hasegawa Toshiro Kamoshida 《Surgery today》1993,23(12):1081-1084
We report herein the case of a 42-year-old man in whom dyspnea on exertion was found to be caused by isolated tricuspid stenosis. Two-dimensional echocardiogram showed thickening of the tricuspid valve with a markedly enlarged right atrium. A color-flow Doppler examination-revealed severe tricuspid stenosis without regurgitation and a Doppler-derived tricuspid diastolic pressure gradient of 23 mmHg. At the time of surgery, the patient was noted to have a stenotic tricuspid valve with thickened leaflets, fused commissures, and almost normal chorda tendineae. The valve leaflets were teased apart to the scattered specimen, and tricuspid valve replacement was successfully performed. Microscopic examination of the specimen demonstrated infective endocarditis. Isolated acquired tricuspid stenosis is extremely rare and, to our knowledge, this is the first case of infective endocarditis being involved as the primary cause. 相似文献
49.
Awoniyi O. Awonuga Nicola Dean Jamal Zaidi Rudiger U. Pittrof Jinan S. Bekir Seang-Lin Tan 《Journal of assisted reproduction and genetics》1996,13(4):293-297
Aim: Our aim was to compare the outcome in subsequent frozen embryo replacement cycles in four groups of patients who had elective cryopreservation of all their embryos because they were considered to be at increased risk of developing severe ovarian hyperstimulation syndrome.
Design: Sixty-two (91%) of 68 IVF cycles (68 patients) in which elective cryopreservation of all embryos was performed were analyzed. All patients continued on the GnRH agonist, buserelin, after oocyte recovery until the onset of vaginal bleeding. Frozen embryo replacement occurred in a hormone replacement cycle that started either on day 3 of the withdrawal bleed (group I;N=15) or after serum estradiol levels had fallen to <100 pmol/L (group II;N=16). The other patients commenced a frozen embryo replacement cycle several months later in either a hormone replacement (group III;N=15) or a natural (group IV;N=16) cycle.
Results: Two patients developed severe ovarian hyperstimulation syndrome. There were no significant differences among the four groups regarding demographic variables, the dose of hMG used, and the clinical outcome. There was a higher but not significantly different clinical pregnancy rate in group I (26.7%), compared to group II (12.5%), group III (13.3%), and group IV (18.8%).
Conclusions: Several options exist for the timing and protocol used for frozen embryo replacement in patients who had elective cryopreservation for the prevention of ovarian hyperstimulation syndrome, none of which was found to be clearly superior in this observational report.Presented at the 1994 Annual Conference of the American Fertility Society. 相似文献
50.
A 73-year-old woman presenting with persistent swelling of the right knee 30 months after total joint arthroplasty was found to have a Candida parapsilosis infection. Treatment with fluconazole resulted in full recovery. 相似文献