全文获取类型
收费全文 | 293255篇 |
免费 | 12994篇 |
国内免费 | 8386篇 |
专业分类
耳鼻咽喉 | 1989篇 |
儿科学 | 8227篇 |
妇产科学 | 4117篇 |
基础医学 | 28262篇 |
口腔科学 | 3760篇 |
临床医学 | 27921篇 |
内科学 | 46802篇 |
皮肤病学 | 1960篇 |
神经病学 | 22103篇 |
特种医学 | 13798篇 |
外国民族医学 | 49篇 |
外科学 | 40131篇 |
综合类 | 25451篇 |
现状与发展 | 28篇 |
一般理论 | 9篇 |
预防医学 | 27195篇 |
眼科学 | 6107篇 |
药学 | 22293篇 |
134篇 | |
中国医学 | 9147篇 |
肿瘤学 | 25152篇 |
出版年
2024年 | 453篇 |
2023年 | 1936篇 |
2022年 | 4769篇 |
2021年 | 6157篇 |
2020年 | 4819篇 |
2019年 | 3945篇 |
2018年 | 25688篇 |
2017年 | 21085篇 |
2016年 | 22913篇 |
2015年 | 6247篇 |
2014年 | 7541篇 |
2013年 | 7519篇 |
2012年 | 16491篇 |
2011年 | 31024篇 |
2010年 | 25986篇 |
2009年 | 17516篇 |
2008年 | 26483篇 |
2007年 | 28613篇 |
2006年 | 7256篇 |
2005年 | 8223篇 |
2004年 | 7680篇 |
2003年 | 8236篇 |
2002年 | 5628篇 |
2001年 | 3031篇 |
2000年 | 2780篇 |
1999年 | 2270篇 |
1998年 | 1473篇 |
1997年 | 1548篇 |
1996年 | 1090篇 |
1995年 | 983篇 |
1994年 | 904篇 |
1993年 | 540篇 |
1992年 | 555篇 |
1991年 | 523篇 |
1990年 | 520篇 |
1989年 | 400篇 |
1988年 | 360篇 |
1987年 | 312篇 |
1986年 | 230篇 |
1985年 | 165篇 |
1984年 | 86篇 |
1983年 | 78篇 |
1982年 | 50篇 |
1980年 | 55篇 |
1938年 | 60篇 |
1937年 | 25篇 |
1935年 | 22篇 |
1934年 | 30篇 |
1932年 | 56篇 |
1930年 | 46篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
81.
82.
83.
84.
85.
表皮生长因子及其受体与流产关系的探讨 总被引:4,自引:0,他引:4
采用放射免疫竞争抑制饱和分析法,检测47例难免流产患者,65例人工流产及20例健康非孕妇女血清表皮生长因子(EGF)水平;同时采用免疫组织化学法检测流产者胚胎组织中表皮生长因子受体(EGFR)表达程度。结果:人工流产组血清EGF水平高于自然流产及非孕妇女,而自然流产与非孕妇女差异无显著性;胚胎组织中EGFR阳性表达率人工流产组明显高于自然流产组。提示:EGF通过与其受体结合对妊娠维持、胚胎及胎儿的 相似文献
86.
Principles for managing penetrating craniocerebral injuries caused by firearm missiles 总被引:1,自引:0,他引:1
X Zhang S Y Yi W P Liu Z W Zhang L G Wang A M Li 《Journal of clinical neuroscience》1996,3(3):229-233
Penetrating craniocerebral firearm injuries remain one of the most lethal causes of all trauma and are common both in war or peace time. Data were reviewed for 4140 severely head-injured patients (Glasgow Coma Scale (GCS) scores 3-8) treated at Xi-Jing Hospital between 1973 and 1993; 51 of these patients had acute penetrating craniocerebral injuries caused by firearm missiles. These patients consisted of 46 males (90.2%) and 5 females (9.8%) ranging in age from 3 months to 48 years (median 22.4 years). The lesion types included 2 tangential wounds, 37 tubular wounds and 12 through-and-through wounds. All cases were urgent with the patients in severe and unstable states. After emergency treatment and operation, 5 cases died (9.8%). Follow up studies at three months showed that 23 cases (45.1%) had made a good recovery. Moderate disability, severe disability and vegetative states in this series were 29.4%, 13.7% and 2.0% respectively. Long term follow up studies indicated that 32 were able to resume their occupation. The principles for managing penetrating craniocerebral firearm injuries and suggestions for operation are discussed. 相似文献
87.
本文报告了1990年5月以来脑干区大型、复杂占位病变15例.其中,位于脑干内3例,脚间窝2例,岩尖部4例,全岩骨区1例,全斜坡区2例,第四脑室内3例.本组采用以扩大了的岩骨入路为主的联合入路,行肿瘤全切除8例,次全切除5例.2例仅作了活检加减压术.除1例死亡外,均恢复良好.本文结合文献,对脑干区手术入路进行了讨论. 相似文献
88.
Stabilization of an inserted tricalcium phosphate spacer enhances the healing of a segmental tibial defect in sheep 总被引:1,自引:0,他引:1
T. -J. Gao T. S. Lindholm T. C. Lindholm B. Kommonen P. Ragni A. Paronzini 《Archives of orthopaedic and trauma surgery》1997,116(5):290-294
The effect of inserting a tricalcium phosphate (TCP) spacer stabilized by a rigid or non-rigid fixation technique on the healing of segmental tibial defects of critical size was established. The osteotomized tibiae, 11 with and 8 without TCP spacers, were fixed by an external circular device in 11 mature sheep and by plates in 8 mature sheep, respectively. Healing was evaluated roentgenographically 16 weeks after the operation. Compared with the defects without TCP spacers, enhanced stability and healing were observed in the defects with TCP spacers under an identical external fixation. Furthermore, a significantly higher incidence of healing was obtained with plate fixation than with external device fixation in the TCP-implanted defects (P < 0.04). An abundant bridging callus was roentgenograpically demonstrated in most of the healed defects, but none in the unhealed defects. The TCP spacer with its mechanical integrity enhances the stability of external fixation, and the stable immobilization provided by rigid fixation is essential for osteoconduction of an inserted TCP spacer in the healing of segmental diaphyseal defects in sheep. 相似文献
89.
Hyun-Min Shin Chul-Jong Park Jong-Yuk Yi Tae-Yoon Kim Chung-Won Kim 《Pediatric dermatology》1996,13(2):146-147
Abstract: Juvenile xanthogranuloma is a xanthomatous and granulomatous condition that frequently arises before 1 year of age and mainly occurs on the head and trunk. We report a rare solitary juvenile xanthogranuloma on the right palm of a 10-year-old girl, present for one year. This solitary involvement of the palm has been reported only twice before. 相似文献
90.
Implantation of porcine bone morphogenetic protein (pBMP) in the muscle induces differentiation of mesenchymal-type cells and results in endochondral bone formation. pBMP was isolated from porcine demineralized bone matrix and purified by hydroxyapatite chromatography, Sephadex G75 gel filtration, preparative sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), preparative isoelectric focusing (IEF), and chromatofocusing fast protein liquid chromatography (FPLC). Porcine BMP has an MW of 26 K and a range of pI from 4.65 to 4.73 determined by SDS-PAGE and IEF, respectively. Reconstitution with the citrate buffer supernatant fraction enables as little as 50 micrograms of the soluble pBMP fractions to induce osteogenesis in an in vivo assay. Chemical modification studies indicate that the osteoinductive potential of the pBMP molecule depends on tyrosine, carboxyl groups, and disulfide bonds and can be increased by modification of sulfhydryl groups. Modification of arginine and tryptophan has no effect on bioactivity. By pepsin-limited proteolysis, fragments of pBMP with an MW of 6-14 K show definite, although reduced, BMP activity. 相似文献