全文获取类型
收费全文 | 356155篇 |
免费 | 36954篇 |
国内免费 | 21141篇 |
专业分类
耳鼻咽喉 | 3711篇 |
儿科学 | 5470篇 |
妇产科学 | 2158篇 |
基础医学 | 23274篇 |
口腔科学 | 7192篇 |
临床医学 | 41960篇 |
内科学 | 30764篇 |
皮肤病学 | 3891篇 |
神经病学 | 8859篇 |
特种医学 | 14471篇 |
外国民族医学 | 24篇 |
外科学 | 30842篇 |
综合类 | 98036篇 |
现状与发展 | 82篇 |
一般理论 | 3篇 |
预防医学 | 41011篇 |
眼科学 | 4464篇 |
药学 | 42902篇 |
573篇 | |
中国医学 | 37294篇 |
肿瘤学 | 17269篇 |
出版年
2025年 | 39篇 |
2024年 | 5190篇 |
2023年 | 6028篇 |
2022年 | 13052篇 |
2021年 | 15469篇 |
2020年 | 13262篇 |
2019年 | 7571篇 |
2018年 | 8149篇 |
2017年 | 10419篇 |
2016年 | 8288篇 |
2015年 | 14541篇 |
2014年 | 18352篇 |
2013年 | 22788篇 |
2012年 | 32477篇 |
2011年 | 34483篇 |
2010年 | 30246篇 |
2009年 | 26954篇 |
2008年 | 27910篇 |
2007年 | 26617篇 |
2006年 | 23445篇 |
2005年 | 18552篇 |
2004年 | 12819篇 |
2003年 | 10375篇 |
2002年 | 7825篇 |
2001年 | 7199篇 |
2000年 | 5306篇 |
1999年 | 2264篇 |
1998年 | 702篇 |
1997年 | 639篇 |
1996年 | 532篇 |
1995年 | 462篇 |
1994年 | 386篇 |
1993年 | 255篇 |
1992年 | 244篇 |
1991年 | 241篇 |
1990年 | 189篇 |
1989年 | 130篇 |
1988年 | 120篇 |
1987年 | 135篇 |
1986年 | 103篇 |
1985年 | 92篇 |
1984年 | 63篇 |
1983年 | 46篇 |
1982年 | 39篇 |
1979年 | 15篇 |
1959年 | 25篇 |
1958年 | 29篇 |
1957年 | 27篇 |
1956年 | 17篇 |
1955年 | 19篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
31.
32.
慢性心力衰竭病人的临床分析 总被引:1,自引:1,他引:0
慢性心力衰竭(CHF)目前是老年人住院和死亡的主要原因,近几年研究结果显示CHF病人出现的肾功能障碍即心肾综合征发病率高,预后差,狭义的心肾综合征特指CHF引起的进行性肾功能损害,并导致肾功能不全,我们回顾性分析我院收治的100例CHF住院病人,着重探讨CHF程度与肾功能不全的发生率及其与住院的时间的关系。现将其临床分析介绍如下。 相似文献
33.
668颗后牙镍铬合金PFM边缘适合性的临床观察 总被引:4,自引:0,他引:4
目的:观察采用2种边缘形式的后牙烤瓷熔附金属全冠边缘适合性和对牙龈健康的影响.方法:对668颗后牙,分别采用2种边缘形式的后牙烤瓷熔附金属全冠(单冠或桥的基牙)在修复2年后进行复查,检测其边缘适合性及牙龈指数(GI)和牙周探诊深度(PD),用统计学方法分析修复体边缘形式与牙龈病变间的关系.结果:采用羽状边缘360°金属脚边的PFM边缘适合性明显优于凹面肩台型边缘PFM,凹面肩台型边缘的PFM的牙龈病变发生率,明显高于羽状边缘360°金属脚边的PFM,而边缘适合性差者较适合性好者牙龈病变发生率显著增高.结论:后牙PFM的边缘采用羽状边缘360°金属脚边是一种好的选择. 相似文献
34.
Monitoring of any release of radioactive materials to the environment is necessary for the environmental protection. Measurement of medical radioactive elements in the hospital sewerage is very important too. However few study of radioactivity in hospital sewerage has been carried out or reported.…… 《中国人民解放军军医大学学报》2007,22(1):65-66
Monitoring of any release of radioactive materials to the environment is necessary for the environmental protection. Measurement of medical radioactive elements in the hospital sewerage is very important too. However, few study of radioactivity in hospital sewerage has been carried out or reported. 相似文献
35.
无创通气的潜在问题和危险因素 总被引:2,自引:0,他引:2
刘春峰 《中国实用儿科杂志》2007,22(12):890-891
在过去的十多年中,无创通气开始出现在急诊急救领域,其应用范围也逐渐拓宽,成为机械通气领域最重要的进展。无创通气[这里主要指正压通气,并不包括持续气道正压(CPAP)]应用于急、慢性呼吸衰竭的患儿取得了显著疗效,而且避免了气管插管、气管切开等有创通气的一些并发症,可以明显降低呼吸机相关肺炎发生率,保持了上呼吸道生理性湿化、温化以及免疫功能,减少了气道损伤,患儿从心理和生理上易于接受。但无创通气也有明显的缺点和潜在问题,不能完全取代有创通气,对于使用机械通气的医护人员来说,要熟悉各种通气方式的利弊,扬长避短,合理使用,… 相似文献
36.
超声对宫角妊娠的诊断及治疗意义 总被引:5,自引:0,他引:5
目的 探讨对误诊率高,危害大的罕见特殊部位宫角妊娠的诊断和治疗。方法 对我院1991-2001年收治的宫角妊娠临床资料进行回顾性分析。结果 宫角妊娠17例中误诊宫内妊娠行人流失败4例。13例行腹部手术,3例行B超监视下人流术,1例行子宫动脉栓塞术。结论 宫角妊娠临床诊断困难,误诊率高,破裂后造成迅猛的腹腔内出血,应提高对少见部位宫角妊娠的认识,减少孕妇死亡。 相似文献
37.
人工流产手术虽然时间短,一般不需麻醉,但毕竟是手术操作,也给受术者带来一定的痛苦[1]。患者由此产生恐惧心理,甚至发生人流综和症等一系列并发症。我院门诊针对这种情况在人流手术中采用利多卡因宫旁阻滞麻醉,取得良好效果,现报道如下。1资料与方法1.1一般资料2005年3月至200 相似文献
38.
Wang Tao Liang Zhihou Sun Shenggang Cao Xuebing Peng Hai Cao Fei Liu Hongjin Tong E-tang 《华中科技大学学报(医学英德文版)》2003,23(2):145-147
Summary To investigate the distribution of possible novel mutations from parkin gene in variant subset of patients with Parkinson’s
disease (PD) in China and explore whether parkin gene plays an important role in the pathogenesis of PD, 70 patients were
divided into early-onset group and late-onset group; 70 healthy subjects were included as controls. Genomic DNA from 70 normal
controls and from those of PD patients were extracted from peripheral blood leukocytes by using standard procedures. Mutations
of parkin gene (exon 1–12) in all the subjects were screened by PCR-single strand conformation polymorphism (SSCP), and further
sequencing was performed in the samples with abnormal SSCP results, in order to confirm the mutation and its location. A new
missense mutation Gly284Arg in a patient and 3 abnormal bands in SSCP electrophoresis from samples of another 3 patients were
found. All the DNA variants were sourced from the samples of the patients with early-onset PD. It was concluded that Parkin
point mutation also partially contributes to the development of early-onset Parkinson’s disease in Chinese.
WANG Tao, male, born in 1961, Associate Professor
This work was supported by grants from the key program of the special scientific project of Scientific & Technologic Agency
of Hubei Province (Serial No. 2001AA308B01) and the Hygienic Research Project of Hygienic Agency of Hubei province (Serial
No. WJ 01529). 相似文献
39.
Objective: To study the relationship between transaldolase activity, protein expression and testosterone synthesis in Leydig cells of pubertal mice. Methods: Leydig cells were cultured for 2 hours and 8 hours, to the Stimulation Group, hCG was added and to the Controls, only the vehicle. The testosterone concentration was then determined by enzyme-linked immunoadsordent assay (ELISA) and the transaldolase activity and protein expression by Western blot. Results: (1) Both the testosterone concentration and the transaldolase activity in both Stimulation Groups were significantly higher than those in the corresponding Controls (2 h: p<0.05-0.01; 8 h: P<0.001); (2) The ratios of the A isoform, the B isoform and the total transaldolase protein to β-actin between the Stimulation and Control Groups did not differ signifi-cantly. Conclusion: hCG stimulates the transaldolase activity as well as the testosterone synthesis in the Leydig cells of pubertal mice, indicating a positive relationship between them. 相似文献
40.
Expression of antibody heavy- and light-chain genes by transfection permits the production of monoclonal antibodies with improved biological and antigen-binding properties. The immunoglobulin genes are placed in vectors containing a gene for encoding a protein that provides a biochemically selectable function in eukaryotic cells; these vectors are transfected into myeloma and hybridoma cells. Selection of drug-resistant cells permits the efficient isolation of the rare cells that express the transfected DNA. By placing heavy and light chains on plasmids with different selectable markers, one can deliver heavy- and light-chain genes simultaneously to the same cell. The transfected immunoglobulin genes are efficiently expressed and the proteins produced are a faithful mirror of the genes that were introduced. Using the standard techniques of genetic engineering and gene transfection, we can now produce antibodies of widely varying structures, including chimeric antibodies with segments derived from different species. These antibodies provide useful reagents to study structure-function relationships within the antibody molecule. Ultimately it will be possible to produce a new generation of antibody molecules with improved antigen-binding properties and effector functions. 相似文献