全文获取类型
收费全文 | 9248篇 |
免费 | 465篇 |
国内免费 | 63篇 |
专业分类
耳鼻咽喉 | 162篇 |
儿科学 | 238篇 |
妇产科学 | 180篇 |
基础医学 | 1131篇 |
口腔科学 | 271篇 |
临床医学 | 524篇 |
内科学 | 2652篇 |
皮肤病学 | 122篇 |
神经病学 | 661篇 |
特种医学 | 257篇 |
外科学 | 1285篇 |
综合类 | 46篇 |
预防医学 | 224篇 |
眼科学 | 89篇 |
药学 | 657篇 |
中国医学 | 49篇 |
肿瘤学 | 1228篇 |
出版年
2023年 | 50篇 |
2022年 | 101篇 |
2021年 | 172篇 |
2020年 | 115篇 |
2019年 | 149篇 |
2018年 | 175篇 |
2017年 | 137篇 |
2016年 | 186篇 |
2015年 | 183篇 |
2014年 | 269篇 |
2013年 | 305篇 |
2012年 | 486篇 |
2011年 | 536篇 |
2010年 | 327篇 |
2009年 | 273篇 |
2008年 | 463篇 |
2007年 | 519篇 |
2006年 | 454篇 |
2005年 | 545篇 |
2004年 | 486篇 |
2003年 | 466篇 |
2002年 | 433篇 |
2001年 | 207篇 |
2000年 | 242篇 |
1999年 | 252篇 |
1998年 | 138篇 |
1997年 | 110篇 |
1996年 | 110篇 |
1995年 | 92篇 |
1994年 | 88篇 |
1993年 | 87篇 |
1992年 | 158篇 |
1991年 | 152篇 |
1990年 | 145篇 |
1989年 | 155篇 |
1988年 | 129篇 |
1987年 | 104篇 |
1986年 | 99篇 |
1985年 | 108篇 |
1984年 | 66篇 |
1983年 | 52篇 |
1982年 | 26篇 |
1980年 | 25篇 |
1979年 | 49篇 |
1978年 | 26篇 |
1975年 | 31篇 |
1973年 | 28篇 |
1970年 | 29篇 |
1969年 | 27篇 |
1968年 | 26篇 |
排序方式: 共有9776条查询结果,搜索用时 406 毫秒
1.
2.
Hiroto Kinoshita Hitomi Nishioka Aya Ikeda Kyoko Ikoma Yoichi Sameshima Hidehisa Ohi Mizuki Tatsuno Junka Kouyama Chiaki Kawamoto Tomohiro Mitsui Yuko Tamura Yu Hashimoto Masashi Nishio Tsuyoshi Ogashiwa Yusuke Saigusa Shin Maeda Hideaki Kimura Reiko Kunisaki Kazuhiko Koike 《Journal of gastroenterology and hepatology》2019,34(11):1929-1939
3.
Kazunori Aizawa Takeshi Hanaoka Hiroki Kasai Kaoru Kogashi Setsuo Kumazaki Jun Koyama Hiroshi Tsutsui Yoshikazu Yazaki Noboru Watanabe Osamu Kinoshita Uichi Ikeda 《Hypertension research》2006,29(2):123-128
The phosphodiesterase-5 (PDE-5) inhibitor, sildenafil, has been reported to produce sustained pulmonary vasodilatation in patients with pulmonary hypertension (PH). Recently, vardenafil, a more potent and selective PDE-5 inhibitor than sildenafil, has been approved for the treatment of erectile dysfunction. However, the long-term effects of oral vardenafil in patients with PH are unknown. We studied five consecutive patients with PH; one with primary pulmonary hypertension, two with chronic pulmonary thromboembolism, one with Eisenmenger syndrome (ventricular septal defect) and one with secondary pulmonary hypertension after a ventricular septal defect closure operation. In an acute hemodynamic trial, vardenafil (5 mg) significantly decreased both the pulmonary vascular resistance (PVR) and systemic vascular resistance (SVR) with an increase in cardiac output. In a chronic hemodynamic trial, the maintenance dose of vardenafil (10 to 15 mg) for 3 months significantly decreased the PVR, but not the SVR, with a 20.7% reduction of the PVR/ SVR ratio. Plasma brain natriuretic peptide (BNP) levels were also significantly decreased after 3 months. This pilot study demonstrates that long-term oral vardenafil therapy may be a safe and effective treatment for patients with PH. 相似文献
4.
Studies on the mechanisms underlying beta-adrenoceptor-mediated relaxation of rat abdominal aorta. 总被引:1,自引:0,他引:1
Mechanisms underlying beta-adrenoceptor (beta-AR)-mediated vascular relaxation were studied in the isolated rat abdominal aorta. In the endothelium-denuded helical preparations, a non-selective beta-AR agonist isoprenaline elicited a concentration-dependent relaxation. In the absence of beta-AR antagonists, isoprenaline-induced relaxation was not practically affected by an adenylyl cyclase inhibitor SQ 22,536 (300 microM), but was strongly diminished by high-KCl (80 mM). Isoprenaline-induced relaxation in the presence of SQ 22,536 was significantly diminished by iberiotoxin (IbTx, 0.1 microM), but was not affected by 4-aminopyridine (4-AP, 3 mM). Isoprenaline-induced relaxation was not also affected by SQ 22,536 (300 microM) even in the presence of CGP20712A (a beta(1)-selective antagonist) and ICI-118,551 (a beta(2)-selective antagonist) (0.1 microM for each), but was strongly diminished by high-KCl. By contrast, SQ 22,536-resistant, isoprenaline-induced relaxation in the presence of CGP20712A plus ICI-118,551 was not affected by IbTx (0.1 microM), but was inhibited significantly by 4-AP (3 mM). These results suggest that in rat abdominal aortic smooth muscle: 1) both beta(1)-/beta(2)-AR- and beta(3)-AR-mediated relaxations substantially involve cAMP-independent mechanisms; 2) beta(1)-/beta(2)-AR-mediated, cAMP-independent relaxant mechanisms are partly attributed to the large-conductance, Ca (2+)-sensitive K(+) (MaxiK, BK) channel whereas beta(3)-AR-mediated relaxant mechanisms are attributed to K(v) channel. 相似文献
5.
6.
Hiroto Egawa Koichi Tanaka Mureo Kasahara Yasutsugu Takada Fumitaka Oike Kohei Ogawa Seisuke Sakamoto Koichi Kozaki Kaoru Taira Takashi Ito 《Liver transplantation》2006,12(10):1512-1518
Living donor liver transplantation (LDLT) for patients with portal vein thrombosis (PVT) involves technical difficulty. The aim of this research was to analyze their preoperative diagnosis of PVT, operative procedures, and postoperative courses of patients with preoperative PVT. Thirty-nine patients of 404 adult patients (9.7%) undergoing LDLT in our hospital from 1996 June to 2004 December had PVT at their transplantation. Twenty-nine patients had intractable ascites, 21 had gastrointestinal bleeding, and 18 had encephalopathy. The thrombus was located in the portal trunk in 23, in the portal trunk and superior mesenteric vein (SMV) in 7, and developed into the SMV and the splenic vein in 8. The occlusive grade was partial in 29, and complete in 10 patients. The thrombus was removed by a simple technique, and eversion and/or incision technique, or total removal of the portal vein (PV). The PV was reconstructed with the thrombectomized native PV, with an interposed vein graft, or porto-caval hemitransposition. Advanced PVT had a significant impact on blood loss and hospital mortality. Three out of 10 patients with residual PVT required radiological and/or surgical intervention after transplantation. In conclusion, thorough planning is essential for a successful LDLT outcome for patients with preexisting PVT. 相似文献
7.
Evidence for a defect in urinary concentrating ability in primary aldosteronism and its reversal by adrenal surgery 总被引:1,自引:0,他引:1
Of 15 patients with primary aldosteronism, 7 had idiopathic adrenal hyperplasia (IHA) and 8 had aldosterone-producing adenoma (APA). In order to determine any renal problems involved in the treatment, the renal clearance of these patients was analyzed and the results compared with those obtained from 12 patients with essential hypertension. With water diuresis or under antidiuresis status, levels of urine volume, Cosm and CH2O in patients with APA were greater (p less than 0.05-p less than 0.001) than those of patients with essential hypertension, while the fractional tubular sodium delivery of the former patients was lower than that of the latter patients (p less than 0.001 or less than 0.05). A similar tendency was observed in clearance studies in patients with IHA, although to a lesser extent. Adrenal surgery for patients with APA normalized these values, but administration of trilostane (3 beta-hydrosteroid dehydrogenase inhibitor) to patients with IHA failed to improve these values. These results indicate that impaired urinary concentrating ability as well as reduced urinary diluting capability is a common feature of primary aldosteronism. Such impaired renal function was improved only in patients with APA after adrenal surgery. 相似文献
8.
9.
10.
Predicting outbreaks: a spatial risk assessment of West Nile virus in British Columbia 总被引:1,自引:0,他引:1
Kaoru Tachiiri Brian Klinkenberg Sunny Mak Jamil Kazmi 《International journal of health geographics》2006,5(1):21-21