全文获取类型
收费全文 | 3714篇 |
免费 | 244篇 |
国内免费 | 143篇 |
专业分类
耳鼻咽喉 | 38篇 |
儿科学 | 98篇 |
妇产科学 | 48篇 |
基础医学 | 464篇 |
口腔科学 | 74篇 |
临床医学 | 359篇 |
内科学 | 846篇 |
皮肤病学 | 293篇 |
神经病学 | 208篇 |
特种医学 | 115篇 |
外科学 | 397篇 |
综合类 | 207篇 |
预防医学 | 234篇 |
眼科学 | 181篇 |
药学 | 311篇 |
2篇 | |
中国医学 | 66篇 |
肿瘤学 | 160篇 |
出版年
2023年 | 23篇 |
2022年 | 48篇 |
2021年 | 87篇 |
2020年 | 67篇 |
2019年 | 100篇 |
2018年 | 122篇 |
2017年 | 86篇 |
2016年 | 81篇 |
2015年 | 102篇 |
2014年 | 93篇 |
2013年 | 177篇 |
2012年 | 245篇 |
2011年 | 233篇 |
2010年 | 149篇 |
2009年 | 100篇 |
2008年 | 181篇 |
2007年 | 243篇 |
2006年 | 201篇 |
2005年 | 213篇 |
2004年 | 164篇 |
2003年 | 156篇 |
2002年 | 162篇 |
2001年 | 138篇 |
2000年 | 145篇 |
1999年 | 127篇 |
1998年 | 49篇 |
1997年 | 43篇 |
1996年 | 44篇 |
1995年 | 36篇 |
1994年 | 19篇 |
1993年 | 12篇 |
1992年 | 41篇 |
1991年 | 42篇 |
1990年 | 46篇 |
1989年 | 46篇 |
1988年 | 51篇 |
1987年 | 42篇 |
1986年 | 22篇 |
1985年 | 12篇 |
1984年 | 17篇 |
1983年 | 13篇 |
1982年 | 7篇 |
1981年 | 9篇 |
1980年 | 12篇 |
1979年 | 8篇 |
1973年 | 7篇 |
1971年 | 8篇 |
1969年 | 7篇 |
1967年 | 12篇 |
1966年 | 5篇 |
排序方式: 共有4101条查询结果,搜索用时 15 毫秒
1.
2.
胃间质瘤的影像学诊断 总被引:6,自引:1,他引:5
胃间质瘤(gastric stromal tumor,GST)是一种较少见的独立起源于胃肠道原始间叶组织的非定向分化的肿瘤,属于消化道间叶性肿瘤[1]。本文报告经手术、病理和免疫组织化学检测9例GST的影像学表现,并探讨其影像学检查的诊断价值。1材料与方法1.1一般资料本组男5例,女4例,年龄43~70岁,平均52岁。临床表现上腹部不适、胀痛、乏力和纳差9例,恶心呕吐5例,黑便3例,消瘦、便秘2例,胃手术史1例。病程1~6个月。查体腹部触及包块6例。1.2方法9例行B超检查,8例行上消化道造影检查,6例行螺旋CT平扫和增强扫描,2例行MRI平扫和增强扫描。手术9例均行光… 相似文献
3.
OBJECTIVE: To study the antibacterial activity of Chinese medicine kou-Kang mouthwash and its acute toxicity, and provide the basis of experiment and therapy for infectious diseases of the oral cavity. METHODS: Minimal inhibitory concentrations (MIC) of kou-Kang mouthwash were determined by the agar dilution method, and the acute toxicity was done. RESULTS: The range of MIC kou-Kang mouthwash against 27 Gram negative bacterial were 0.03-1.0 g.ml-1. MIC50 was 0.125 g.ml-1 and MIC90 was 0.125-0.5 g.ml-1. The range of MIC kou-Kang mouthwash against 21 Gram positive bacterial was 0.008-0.5 g.ml-1. The range of MIC50 and MIC90 were 0.015-0.125 g.ml-1 and 0.015-0.5 g.ml-1, respectively. The value of MIC was 0.015 g.ml-1 against candidia albicans. The acute toxic test indicated that the maximum tolerance dose was 417.6 g.kg-1 and 210 times as much as the clinical dose a day. No death of animals or toxicity and side-effect occurred in the test. CONCLUSION: Kou-Kang mouthwash shows a potent antibacterial activity against various pathogens of the oral cavity. Its antibiotic activity against Gram positive bacteria was 2-8 times stronger than that against Gram negative bacteria. It has low toxicity and can be used in clinical application. 相似文献
4.
M Gómez-Silva L Garza-Oca?as N Waksman V Rivas A Pi?eyro-López 《Toxicology in vitro》2005,19(1):47-53
T-514 (Peroxisomicine A(1)) from Karwinskia humboldtiana is a dimeric hydroxyanthracenone with a highly selective cytotoxic effect on tumor cells. We evaluated the metabolism of this compound in two in vitro systems (liver microsomes and hepatocytes) and assessed the cytotoxicity of its metabolites on normal and tumor cells. Microsomes (12.5, 125 and 250 microg of protein/ml) and hepatocytes (1 x 10(6) cells/ml) were incubated with the toxin (25 microM) for 0.5, 1, 3, 6, 9, 12 and 24 h and the samples were examined using chromatographic analysis and UV spectra. Two metabolites (M1 and M2) were detected in the rat microsomes and one (M1) in the monkey microsomes. The retention times and UV spectra of the peaks were very similar to those of the toxin T-514. M1 was isolated and identified as a mixture of two isomers. The cytotoxicity of the metabolites was evaluated in Chang liver and Hep G2 cells but they did not show the selective cytotoxic effect on tumor cells seen in the original compound. 相似文献
5.
目的:为培养适应在新医学模式下开展以病人为中心整体护理工作的护理人员,改革传统临床教学模式,采用护理导师教学法,以提高教学质量.方法:制定导师职责,制定导师的选择聘任标准,制定导师培训方案,实施导师制教学法的临床过程,实行双向教学评价,通过以上活动达到提高教学质量的效果.结果:320余名实习学生调查表明,12%的学生认为护理导师教学法形式明显优于其它教学形式,82%的学生认为优于其它教学形式.结论:护理导师教学法提高了临床教学水平和导师的整体素质,也促进了临床护理质量和临床教学质量的不断提高. 相似文献
6.
Marcela Hernández Hoyos Piotr Orłowski Ewa Piątkowska-Janko Piotr Bogorodzki Maciej Orkisz 《International journal of computer assisted radiology and surgery》2006,1(1):51-61
The accuracy of 2D phase contrast (PC) magnetic resonance angiography (MRA) depends on the alignment between the vessels and
the imaging plane. PC MRA imaging of blood flow is challenging when the flow in several vessels is to be evaluated with one
acquisition. For this purpose, semi-automatic determination of the plane most perpendicular to several vessels is proposed
based on centerlines extracted from 3D MRA. Arterial centerlines are extracted from 3D MRA based on iterative estimation-prediction,
multi-scale analysis of image moments, and a second-order shape model. The optimal plane is determined by minimizing misalignment
between its normal vector and the centerlines’ tangent vectors. The method was evaluated on a phantom and on 35 patients,
by seeking the optimal plane for cerebral blood flow quantification simultaneously in internal carotids and vertebral arteries.
In the phantom, difference of orientation and of height between known and calculated planes was 1.2° and 2.5 mm, respectively.
In the patients, all but one centerline were correctly extracted and the misalignment of the plane was within 12° per artery.
Semi-automatic centerline extraction simplifies and automates determination of the plane orthogonal to one vessel, thereby
permitting automatic simultaneous minimization of the misalignment with several vessels in PC MRA. 相似文献
7.
8.
9.
Ketai LH; Williamson MR; Telepak RJ; Levy H; Koster FT; Nolte KB; Allen SE 《Radiology》1994,191(3):665
10.