全文获取类型
收费全文 | 14533篇 |
免费 | 625篇 |
国内免费 | 78篇 |
专业分类
耳鼻咽喉 | 133篇 |
儿科学 | 295篇 |
妇产科学 | 140篇 |
基础医学 | 1983篇 |
口腔科学 | 279篇 |
临床医学 | 972篇 |
内科学 | 3407篇 |
皮肤病学 | 187篇 |
神经病学 | 1050篇 |
特种医学 | 611篇 |
外科学 | 2790篇 |
综合类 | 39篇 |
预防医学 | 442篇 |
眼科学 | 326篇 |
药学 | 1270篇 |
中国医学 | 42篇 |
肿瘤学 | 1270篇 |
出版年
2023年 | 77篇 |
2022年 | 153篇 |
2021年 | 247篇 |
2020年 | 139篇 |
2019年 | 192篇 |
2018年 | 249篇 |
2017年 | 208篇 |
2016年 | 212篇 |
2015年 | 257篇 |
2014年 | 330篇 |
2013年 | 373篇 |
2012年 | 643篇 |
2011年 | 715篇 |
2010年 | 352篇 |
2009年 | 317篇 |
2008年 | 679篇 |
2007年 | 689篇 |
2006年 | 685篇 |
2005年 | 739篇 |
2004年 | 715篇 |
2003年 | 626篇 |
2002年 | 734篇 |
2001年 | 355篇 |
2000年 | 421篇 |
1999年 | 420篇 |
1998年 | 191篇 |
1997年 | 152篇 |
1996年 | 155篇 |
1995年 | 145篇 |
1994年 | 140篇 |
1993年 | 140篇 |
1992年 | 373篇 |
1991年 | 342篇 |
1990年 | 297篇 |
1989年 | 332篇 |
1988年 | 299篇 |
1987年 | 268篇 |
1986年 | 258篇 |
1985年 | 249篇 |
1984年 | 164篇 |
1983年 | 137篇 |
1982年 | 76篇 |
1981年 | 59篇 |
1980年 | 57篇 |
1979年 | 135篇 |
1978年 | 105篇 |
1977年 | 64篇 |
1975年 | 67篇 |
1974年 | 58篇 |
1973年 | 55篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
32.
Hitoshi Matsuda Tomomi Hasegawa Takayo Maekawa Yutaka Okita 《Annals of thoracic and cardiovascular surgery》2005,11(2):132-134
A 23-year-old man was admitted for an aortic root aneurysm with mild aortic valve regurgitation (AR) and a small pressure gradient. At surgery, findings of aortic valve, one normal left posterior commissure and very rudimentary right anterior commissure, was compatible with the uni-commisural aortic valve. Aortic root replacement with valve-sparing technique was performed. Four years later no residual AR was observed. 相似文献
33.
Attenuation of lung injury in allograft rejection using NF-kappaB decoy transfection-novel strategy for use in lung transplantation. 总被引:5,自引:0,他引:5
34.
Kunihiro Ichinose Mitsuru Nakamura Kenji Takezawa Ichiro Masutomi Yoichi Shima Yoko Hirayama Kahoko Sorimachi Teruhiko Shimizu Hiroyo Ishikawa Namiko Kaji Sayaka Nakajima Michiko Wataru Shiho Nishigaki Hiroshi Suwa Yosuke Toyama Masaki Okumura Yoshikazu Ishitsuka Ken Shimizu Kazuya Kokubo Kenji Sasaki Shodai Saito 《Seishin shinkeigaku zasshi》2006,108(9):945-954
35.
Magnetic resonance imaging of 31 meningiomas in 29 patients was retrospectively reviewed and compared with pathologic specimens in 25 tumors to investigate how magnetic resonance imaging could delineate a tumor-brain interface. The thick, collagenous connective tissue, which was seen around four tumors, was shown as a low signal intensity rim on both a T1-weighted image and a T2-weighted image. A rim of low signal intensity on a T1-weighted image and high signal intensity on a T2-weighted image most likely represented cerebrospinal fluid space: this finding was seen around eight tumors. No distinct rim could be identified in five tumors. Of these five, two tumors grew invasively into the brain. Although mixed features predominated in meningiomas, magnetic resonance imaging could well delineate a tumor-brain relationship in most of the cases. 相似文献
36.
Takakura Yoshinobu Fujita Takuya Hashida Mitsuru Sezaki Hitoshi 《Pharmaceutical research》1990,7(4):339-346
As part of the strategy for the design of macromolecular carriers for drug targeting, the disposition characteristics of macromolecules were studied in mice bearing tumors that served as target tissues. Eight kinds of macromolecules including four polysaccharides and four proteins with different molecular weights and electric charges were used; tissue distribution and tumor localization after intravenous injection were studied. Pharmacokinetic analysis revealed that the tissue radioactivity uptake rate index calculated in terms of clearance was different among the tested compounds; especially, the urinary radioactivity excretion clearances and the total hepatic radioactivity uptake clearances varied widely. Compounds with low molecular weights (approximately 10 kD) or positive charges showed lower tumor radioactivity accumulation; radioactivity was rapidly eliminated from the plasma via rapid urinary excretion or extensive hepatic uptake, respectively. On the other hand, large and negatively charged compounds, carboxymethyl dextran, bovine serum albumin, and mouse immunoglobulin G, showed higher radioactivity accumulation in the tumor (calculated total amounts were 15.6, 10.8, and 20.8% of the dose, respectively) and prolonged retention in the circulation. These results demonstrated that the total systemic exposure rather than the uptake rate index was correlated with total tumor uptake. Molecular weight and electric charge of the macromolecules significantly affected their disposition characteristics and, consequently, determined radioactivity accumulation in the tumor. It was concluded that a drug–carrier complex designed for systemic tumor targeting should be polyanionic in nature and larger than 70,000 in molecular weight. 相似文献
37.
K Matsuda Y Kiyota N Tamura M Takahashi H Miki H Suzuki Y Nakagawa Y Satou M Noda T Nakamura 《Kyobu geka. The Japanese journal of thoracic surgery》1990,43(5):389-391
A 64-year-old man, who had an aneurysm of aortic arch associated with the aberrant right subclavian artery, was treated successfully. He was pointed out to have an aneurysm of aortic arch three years ago. Three years later angiograms and computed tomography revealed that it became larger compared with the initial finding. He underwent a replacement of the aortic arch using a woven Dacron graft under open distal method. Aberrant subclavian artery was not involved in the aneurysm. But because the left subclavian artery was involved in it, a woven Dacron graft was interposed between the ascending aorta and left subclavian artery. Postoperative course was uneventful and there were no complications. 相似文献
38.
39.
Yoshinori Hamada Masazumi Tsuji Munehisa Kogata Koshiro Hioki Tadashi Matsuda 《Surgery today》1995,25(8):754-756
We report herein a new method of performing laparoscopic pyloromyotomy for infantile hypertrophic pyloric stenosis, using refined surgical techniques. The pyloric tumor was immobilized by grasping the first portion of the duodenum and the anterior wall of the stomach, and electrocoagulation was used prior to incising the pyloric tumor to minimize bleeding during the procedure. Although this technique has been applied in only two patients so far, we present the details herein. We believe that with technical and instrumental refinements, the speed and safety of laparoscopic pyloromyotomy will improve and it will become an alternative to open surgery in pediatric patients. 相似文献
40.
Beta-adrenoceptors in femoral and mesenteric arteries from 13-week-old spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto (WKY) rats were studied using radioligand binding assays and were compared with in vitro measurements of beta-adrenoceptor-mediated relaxation. The relaxant responses to noradrenaline via beta-adrenoceptors were significantly decreased in the SHR femoral artery when compared with the WKY femoral artery. However, under the same conditions, arterial relaxant responses to forskolin, an activator of adenylate cyclase, were not significantly different between SHR and WKY rats. Specific binding of 125I-iodocyanopindolol to membranes prepared from femoral arteries of SHR and WKY rats was saturable and of high affinity. Neither the equilibrium dissociation constant of 125I-iodocyanopindolol, nor the maximum number of binding sites were significantly different between SHR and WKY rats. Similar results were obtained in the case of mesenteric arteries from SHR and WKY rats. These results indicate that the decreased responsiveness to beta-adrenoceptor stimulation in SHR arteries is not associated with alterations in beta-adrenoceptors and further support the hypothesis that a reduced function of the stimulatory guanosine triphosphate-binding protein is responsible for the decreased responsiveness to a variety of receptor agonists whose mechanism of action involves adenylate cyclase activation. 相似文献