全文获取类型
收费全文 | 102185篇 |
免费 | 8735篇 |
国内免费 | 6095篇 |
专业分类
耳鼻咽喉 | 1104篇 |
儿科学 | 1531篇 |
妇产科学 | 2304篇 |
基础医学 | 12296篇 |
口腔科学 | 1948篇 |
临床医学 | 13540篇 |
内科学 | 15762篇 |
皮肤病学 | 893篇 |
神经病学 | 5580篇 |
特种医学 | 3508篇 |
外国民族医学 | 42篇 |
外科学 | 11010篇 |
综合类 | 14729篇 |
现状与发展 | 23篇 |
一般理论 | 20篇 |
预防医学 | 5847篇 |
眼科学 | 2823篇 |
药学 | 10624篇 |
56篇 | |
中国医学 | 4813篇 |
肿瘤学 | 8562篇 |
出版年
2024年 | 176篇 |
2023年 | 1309篇 |
2022年 | 1935篇 |
2021年 | 4682篇 |
2020年 | 3489篇 |
2019年 | 3216篇 |
2018年 | 3535篇 |
2017年 | 2922篇 |
2016年 | 2839篇 |
2015年 | 4406篇 |
2014年 | 5606篇 |
2013年 | 5003篇 |
2012年 | 7522篇 |
2011年 | 8263篇 |
2010年 | 4971篇 |
2009年 | 3819篇 |
2008年 | 5270篇 |
2007年 | 5566篇 |
2006年 | 5402篇 |
2005年 | 5705篇 |
2004年 | 3830篇 |
2003年 | 3398篇 |
2002年 | 2999篇 |
2001年 | 2444篇 |
2000年 | 2661篇 |
1999年 | 2694篇 |
1998年 | 1577篇 |
1997年 | 1478篇 |
1996年 | 1320篇 |
1995年 | 1164篇 |
1994年 | 986篇 |
1993年 | 635篇 |
1992年 | 1001篇 |
1991年 | 812篇 |
1990年 | 686篇 |
1989年 | 605篇 |
1988年 | 600篇 |
1987年 | 512篇 |
1986年 | 418篇 |
1985年 | 330篇 |
1984年 | 208篇 |
1983年 | 159篇 |
1982年 | 85篇 |
1981年 | 98篇 |
1980年 | 83篇 |
1979年 | 115篇 |
1978年 | 53篇 |
1977年 | 56篇 |
1975年 | 44篇 |
1974年 | 45篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
Xiang SH Wang L Abreu M Huang CC Kwong PD Rosenberg E Robinson JE Sodroski J 《Virology》2003,315(1):124-134
Human immunodeficiency virus (HIV-1) enters target cells by binding its gp120 exterior envelope glycoprotein to CD4 and one of the chemokine receptors, CCR5 or CXCR4. CD4-induced (CD4i) antibodies bind gp120 more efficiently after CD4 binding and block the interaction with the chemokine receptor. Examples of CD4i antibodies are limited, and the prototypes of the CD4i antibodies exhibit only weak neutralizing activity against primary, clinical HIV-1 isolates. Here we report the identification of a novel antibody, E51, that exhibits CD4-induced binding to gp120 and neutralizes primary HIV-1 more efficiently than the prototypic CD4i antibodies. The E51 antibody blocks the interaction of gp120-CD4 complexes with CCR5 and binds to a highly conserved, basic gp120 element composed of the beta 19-strand and surrounding structures. Thus, on primary HIV-1 isolates, this gp120 region, which has been previously implicated in chemokine receptor binding, is accessible to a subset of CD4i antibodies. 相似文献
992.
大鼠三角肌前,后部的运动神经元 总被引:1,自引:0,他引:1
为了解主动肌与拮抗肌的运动神经元,应用HRP逆行追踪技术研究了大鼠三角肌前部、后部的运动神经元。三角肌前部的运动神经元池位于C4-6脊髓前外侧核背部及其与后外侧核之间。三角肌后部的运动神经元池位于C4-7脊髓外侧核及其与前外侧核之间。与前池略有重叠。 相似文献
993.
An autopsy-proved case of AIDS in Taiwan 总被引:1,自引:0,他引:1
K T Lin S H Huang C L Kao K M Huang J C Yu T P Hung M Y Chou W T Liu C T Fang Y T Kuo 《Asian Pacific journal of allergy and immunology / launched by the Allergy and Immunology Society of Thailand》1987,5(1):25-31
The first case of AIDS positively identified in a non-foreigner in Taiwan was a 25-year-old unmarried male who had practiced homosexuality for ten years. The patient began to have abdominal pain accompanied with loose stools and weight loss in June 1985, followed by fever, cough, headache, dizziness, and loss of memory. Facial hyperpigmentation and extensive oroesophageal candidiasis were noted. Laboratory studies showed severe lymphopenia with a reversed T-helper to T-suppressor ratio, cutaneous anergy and polyclonal gammopathy. Human immunodeficiency virus (HIV) antibodies were positive by ELISA and Western blot, and the virus was isolated from the blood. At autopsy, disseminated cytomegalovirus infection, extensive CNS toxoplasmosis and early lesions of Kaposi's sarcoma were demonstrated. The detection of HIV in the adrenal medulla supports the consensus that the virus is neurotropic. 相似文献
994.
用Westem Blot方法确认周围神经于内含有S-100,然后运用免疫组化PAP方法对Wistar大鼠坐骨神经的近侧和远侧进行S-100检测,染色结果用电子图像进行系统分析处理。结果显示:S-100分布于周围神经束间膜,雪旺氏细胞浆内及细胞膜上,神经轴内未见有S-100存在,图像处理结果证实,正常大鼠坐骨神经干内的S-100呈均匀分布。 相似文献
995.
H M Vijay H Huang N M Young I L Bernstein 《International archives of allergy and applied immunology》1979,60(3):229-239
Extracts of Alternaria tenuis and Alternaria solani were separated into dialyzable (molecular weight less than 10,000) and non-dialyzable forms. The latter was further fractionated by gel filtration through Sephadex G-100 followed by ion-exchange chromatography on DEAE-cellulose. The dialyzable material was fractionated by gel filtration through Sephadex G-50. The allergenic activities of the fractions obtained from the A. tenuis extract was measured in vitro by the radioallergosorbent test assay and the allergenic potency was measured by radioallergosorbent test inhibition assay. Allergenic activity was detected in most of the non-dialyzable fractions, the majority of the activity being in the last G-100 fraction (MW approximately 20,000) which was predominantly protein in nature. The same component may be responsible for the activity found in the dialyzate and its first G-50 fraction since the immunodiffusion studies indicated that the last G-100 fraction has antigenic components in common with those of the first G-50 fraction. In addition, cross-reactions between A. tenuis and A. solani extracts show that the two species share common antigenic determinants. 相似文献
996.
我们已经在减毒鼠伤寒沙门菌SL3261以融合蛋白的形式表达了人工合成的恶性疟原虫杂合113肽基因AB(GZ-AB)。活菌以2×109CFU经口服免疫新西兰家兔,用ELISA测定抗体水平,结果于首次免疫或加强免疫后都可检测到一定水平的特异性抗体。所免疫的家免可以诱发针对恶性疟原虫抗原及GZ-AB的迟发性超敏反应(DTH)。我们的研究表明,含有多个恶性疟原虫抗原表位的人工合成基因可以在减毒鼠伤寒沙门菌中表达,活菌可诱发家兔产生特异的体液免疫及细胞免疫,为恶性疟口服活菌苗的制备打下基础。 相似文献
997.
G An T H Huang J Tesfaigzi J Garcia-Heras D H Ledbetter D M Carlson R Wu 《American journal of respiratory cell and molecular biology》1992,7(1):104-111
An unusual expression of a putative squamous cell marker, small proline-rich protein (spr1), in mucociliary epithelial cells of conducting airways was demonstrated in a serum-free culture system. A cDNA clone was isolated from the cDNA library of monkey tracheobronchial epithelial (TBE) cells by differential hybridization. This cDNA clone, MT5, exhibited 98% homology to a DNA sequence obtained from human keratinocytes treated with either UV light or phorbol esters (T. Kartasova et al., 1988, Mol. Cell. Biol. 8:2195-2230). The predicted peptide of MT5 is unusual for its high content of proline (29%), glutamine (18%), and cysteine (9%) and its repeated PKVPEPC units. The level of spr1 mRNA in cultured cells was inhibited more than 90% by vitamin A. In contrast, phorbol 12-myristate 13-acetate (PMA) stimulated the level of spr1 mRNA by 3- to 8-fold. This differential regulation coincided with the effects of these chemicals on the cornification of cultured TBE cells. Using MT5 as a probe, we have localized the tracheal spr1 gene on the human chromosome 1 by a Southern blot analysis using a panel of human-rodent somatic cell hybrid DNAs. The gene was further sublocalized to bands q22-23 by in situ hybridization. 相似文献
998.
Shian-Sen Shie Ching-Tai Huang Hsieh-Shong Leu 《Journal of microbiology, immunology, and infection》2005,38(4):277-282
There were 40 cases of Achromobacter xylosoxidans bacteremia during a 6-year period in a medical center in northern Taiwan. Males outnumbered females (72.5% vs 27.5%). Common underlying diseases and conditions in these 40 bacteremic patients were malignancies (57.5%), central venous catheter implants (55%), surgery (35%), neutropenia (30%) and use of steroids (25%). Recurrent bacteremia occurred in 4 patients (10%), all of whom had a central venous catheter implant which was considered the most probable source of infection. More than one-quarter (27.5%) of the cases were community acquired. The mortality rate due to A. xylosoxidans bacteremia was 47.5%. Risk factors significantly associated with mortality were nosocomial acquisition and polymicrobial bacteremia. Disk susceptibility testing showed that these isolates were resistant to aminoglycosides and most cephalosporins but were susceptible to piperacillin, imipenem, ceftazidime and trimethoprim-sulfamethoxazole. 相似文献
999.
1000.
Histiocytic lesions involving the bone marrow include a number of reactive and neoplastic disorders. This article discusses the morphologic, immunophenotypic, and genotypic features of a variety of diseases associated with histiocytes and/or monocytes. Lysosomal storage disorders and hemophagocytic syndromes are often first diagnosed by bone marrow examination. Granulomas involving the bone marrow may also be the first indication of a systemic disorder. Apart from acute and chronic monocytic leukemias, the bone marrow is rarely involved by malignant histiocytic disorders, of which Langerhans cell histiocytosis is the most common. 相似文献