全文获取类型
收费全文 | 635116篇 |
免费 | 56797篇 |
国内免费 | 43039篇 |
专业分类
耳鼻咽喉 | 5355篇 |
儿科学 | 7713篇 |
妇产科学 | 8418篇 |
基础医学 | 72127篇 |
口腔科学 | 10879篇 |
临床医学 | 88422篇 |
内科学 | 88847篇 |
皮肤病学 | 6511篇 |
神经病学 | 32277篇 |
特种医学 | 23339篇 |
外国民族医学 | 371篇 |
外科学 | 59977篇 |
综合类 | 111480篇 |
现状与发展 | 132篇 |
一般理论 | 50篇 |
预防医学 | 43883篇 |
眼科学 | 18253篇 |
药学 | 67288篇 |
678篇 | |
中国医学 | 39116篇 |
肿瘤学 | 49836篇 |
出版年
2024年 | 1990篇 |
2023年 | 8830篇 |
2022年 | 23272篇 |
2021年 | 29568篇 |
2020年 | 22741篇 |
2019年 | 19361篇 |
2018年 | 20336篇 |
2017年 | 18977篇 |
2016年 | 17577篇 |
2015年 | 27142篇 |
2014年 | 33977篇 |
2013年 | 30898篇 |
2012年 | 45904篇 |
2011年 | 51886篇 |
2010年 | 34262篇 |
2009年 | 27688篇 |
2008年 | 35408篇 |
2007年 | 35341篇 |
2006年 | 34571篇 |
2005年 | 33496篇 |
2004年 | 22011篇 |
2003年 | 20844篇 |
2002年 | 17667篇 |
2001年 | 15497篇 |
2000年 | 15786篇 |
1999年 | 16341篇 |
1998年 | 10007篇 |
1997年 | 9848篇 |
1996年 | 7704篇 |
1995年 | 7157篇 |
1994年 | 5930篇 |
1993年 | 3898篇 |
1992年 | 4966篇 |
1991年 | 4300篇 |
1990年 | 3711篇 |
1989年 | 3241篇 |
1988年 | 2691篇 |
1987年 | 2351篇 |
1986年 | 1944篇 |
1985年 | 1523篇 |
1984年 | 860篇 |
1983年 | 622篇 |
1982年 | 365篇 |
1981年 | 378篇 |
1980年 | 294篇 |
1979年 | 364篇 |
1978年 | 153篇 |
1977年 | 141篇 |
1974年 | 144篇 |
1973年 | 119篇 |
排序方式: 共有10000条查询结果,搜索用时 35 毫秒
81.
本文对以重组淋球菌IgA蛋白酶为抗原制备的7株特异性McAb的特性进行了初步研究。结果有5株(1C8、1E5、1F11、1G3和2E6)能中和淋球菌IgA蛋白酶活性。经相加试验初步证明,其中1F11、2G3与其它3株McAb的作用位点不同。因此,淋球菌IgA蛋白酶至少存在3个中和表位。 相似文献
82.
J Wang G Rivas M Chicharro 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》1997,439(1):55-61
Miniaturized glucose biosensors, prepared by electrochemical deposition of iridium and glucose oxidase (GOx), are characterized. The iridium network offers good retention of GOx and efficient preferential electrocatalytic detection of the liberated hydrogen peroxide at potentials lower than those of common interfering substances (the ascorbic acid signal actually shifts to a higher potential). The remarkable selectivity thus achieved towards the detection of glucose is coupled to a very fast response. Unlike analogous preparations of noble metal carbon fiber biosensors, a two-step electrodeposition process is required for the fabrication of Ir/GOx microelectrodes. The dependence of the biosensor response upon electrodeposition parameters, such as amounts of GOx and iridium or plating time is examined and optimized. Scanning electron microscopy is used to characterized the growth patterns of the iridium and Ir/GOx layers. The high selectivity associated with electrodeposited iridium matrices makes them very attractive for localizing other hydrogen-peroxide-liberating oxidases. 相似文献
83.
84.
报告8例Wegener肉芽肿病。本组疾病的病理特点均表现为坏死性血管炎及肉芽形成。临床特点为:发热(38-40℃)、鼻塞、鼻衄、咳嗽、口腔及鼻咽部溃疡,皮下结节:X线表现为肺部多发性结节及空洞阴影,副鼻窦炎症。尿常规检查异常,诊断主要依靠病变组织活检。环磷酰胺和肾上腺皮质激素联合治疗效果显著。 相似文献
85.
Five commercially available nitropolyclyclic aromatic hydrocarbons (nitro-PAH), namely, 4-nitrobiphenyl, 2-nitrofluorene, 9-nitroanthracene, 1-nitropyrene, and 2,7-dinitrofluorene, were exposed under restricted sunlight in the open air. The direct-acting mutagenicities of the samples after an exposure of 45 days were measured in order to compare them with those of the original samples in the Ames Salmonella typhimurium bioassay. It was found that the mutagenicities of some nitro-PAH do not change significantly while the mutagenicities of others increase or decrease after exposure. A preliminary study of nitro-PAH reaction products after exposure using GC, GC/MS, and FT-IR is also reported. 相似文献
86.
Periannan Kuppusamy Penghai Wang Michael Chzhan Jay L. Zweier 《Magnetic resonance in medicine》1997,37(4):479-483
The application of electron paramagnetic resonance imaging (EPRI) to obtain information from biological samples has been limited by the lack of ideal single line radical labels. The commonly used nitroxides exhibit multiple lines causing either hyperfine-based limitations in the maximum obtainable image resolution or hyperfine-based artifacts in the reconstructed image. The use of a novel single-line triarylmethyl paramagnetic label that enables marked enhancement in image quality and resolution is reported. This label exhibits a single line EPR spectrum that is sharp (linewidth ~60 mG in the absence of oxygen) and relatively stable in tissues. The potential of this label in enabling high resolution EPR imaging of biological samples was demonstrated in a series of phantoms and isolated biological organs such as the rat kidney. The images demonstrate that resolutions better than 100 μm could be obtained at L-band on samples of up to 20 mm in size. 相似文献
87.
中老年人前列腺体积增长的城乡差异 总被引:27,自引:1,他引:26
为了解国人中年以后前列腺的生长情况及其可能的影响因素,对北京、河北、湖北等地四个社区的城乡居民前列腺体积进行了经腹B超测量。结果表明城区居民的前列腺体积明显大于相应年龄段的农村居民,城区居民的前列腺增长速率比农村居民高二倍。生活环境和饮食习惯的不同可能为其原因之一。 相似文献
88.
89.
Clinical analysis of 107 cases with chemical burns 总被引:1,自引:0,他引:1
G H Li 《中华整形烧伤外科杂志》1990,6(1):34-5, 76
From 1978 to 1987 107 cases of chemical burns were treated. The patients were mainly young and middle age people (83.08%), with mean burned areas 17.8%. The majority of involved parts were low extremities. 57.44% of burned eyes became blind. Mean days in hospital were 43 days. Cure rate was 98.13% and death rate 1.87%. We emphasized that burned wounds must instantly be washed down with water, intoxication resulting from chemical matters must be effectively treated. Diagnosis of depth of burned wound by acids and means of prevention of chemical burns were also discussed. 相似文献
90.