全文获取类型
收费全文 | 27300篇 |
免费 | 1376篇 |
国内免费 | 390篇 |
专业分类
耳鼻咽喉 | 381篇 |
儿科学 | 692篇 |
妇产科学 | 606篇 |
基础医学 | 4545篇 |
口腔科学 | 691篇 |
临床医学 | 1965篇 |
内科学 | 3563篇 |
皮肤病学 | 725篇 |
神经病学 | 2116篇 |
特种医学 | 2089篇 |
外国民族医学 | 1篇 |
外科学 | 3839篇 |
综合类 | 1216篇 |
一般理论 | 2篇 |
预防医学 | 1970篇 |
眼科学 | 438篇 |
药学 | 2568篇 |
6篇 | |
中国医学 | 416篇 |
肿瘤学 | 1237篇 |
出版年
2023年 | 159篇 |
2022年 | 300篇 |
2021年 | 545篇 |
2020年 | 382篇 |
2019年 | 468篇 |
2018年 | 710篇 |
2017年 | 577篇 |
2016年 | 697篇 |
2015年 | 766篇 |
2014年 | 927篇 |
2013年 | 1354篇 |
2012年 | 1876篇 |
2011年 | 2216篇 |
2010年 | 1303篇 |
2009年 | 770篇 |
2008年 | 1408篇 |
2007年 | 1599篇 |
2006年 | 1546篇 |
2005年 | 1312篇 |
2004年 | 1311篇 |
2003年 | 1426篇 |
2002年 | 1249篇 |
2001年 | 940篇 |
2000年 | 976篇 |
1999年 | 608篇 |
1998年 | 241篇 |
1997年 | 214篇 |
1996年 | 137篇 |
1995年 | 149篇 |
1994年 | 117篇 |
1993年 | 87篇 |
1992年 | 157篇 |
1991年 | 135篇 |
1990年 | 139篇 |
1989年 | 123篇 |
1988年 | 124篇 |
1987年 | 89篇 |
1986年 | 83篇 |
1985年 | 126篇 |
1984年 | 98篇 |
1983年 | 86篇 |
1982年 | 81篇 |
1981年 | 71篇 |
1979年 | 86篇 |
1978年 | 89篇 |
1976年 | 72篇 |
1975年 | 93篇 |
1974年 | 77篇 |
1973年 | 70篇 |
1971年 | 67篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Silviene Fabiana De Oliveira Eliane Barbosa Dos Santos Patrícia Jeanne De Souza Mendona Daniela Cristiane Da Cruz Rocha Sidney Emanuel Batista Dos Santos 《American journal of human biology》2001,13(6):718-720
The group‐specific component (GC) system is of interest in anthropological genetic studies because the distribution of its subtypes distinguishes among major ethnic groups. The GC system was analyzed in Curiaú and Pacoval, two remnant Quilombo populations (African‐derived populations) from the Brazilian Amazon. There was no significant statistical difference in allelic frequencies between the two populations or between them and three other African‐derived Brazilian populations (Mimbó, Sítio Velho, and Gaucinha in Northeastern Brazil). These populations share similarities among themselves and with African populations (high frequencies of GC*1F and lower frequencies of GC*1S), which may reflect the influence of a high level of African contribution to their formation, but there is a clear difference between them and Europeans and South American Indians. It is suggested that the GC system is a useful marker for studying relationships between single populations and major ethnic groups, but does not discriminate between populations which share the same parental stock. Am. J. Hum. Biol. 13:718–720, 2001. © 2001 Wiley‐Liss, Inc. 相似文献
102.
Countertransference in therapists working with patients with posttraumatic stress disorder (PTSD) differs from countertransference in other psychotherapeutical settings. In this article we discuss the specificities of counter- transference in treating PTSD patients and its relation to empathy. The most difficult countertransference problems occur in treating multiply traumatized patients. Countertransference may occur towards an event (e.g., war), patients who have killed people, as well as to colleagues who avoid treating PTSD patients, or towards a supervisor who avoids, either directly or indirectly, supervision of therapists working with PTSD patients. Our recommendation for the prevention of problems in treating PTSD patients include : 1) careful selection of the therapist or helper, both in the personality structure and training; 2) prevention by debriefing and team work and peer supervision; and 3) education - theoretical, practical, and therapeutical. 相似文献
103.
104.
肺神经内分泌癌的免疫组化与免疫电镜研究 总被引:3,自引:1,他引:3
本文应用免疫组化与免疫电镜技术对20例肺神经内分泌癌进行了研究,另6例非神经内分泌癌作为对照。结果表明:嗜铬颗粒蛋白A免疫组化染色19/20例阳性,免疫电镜能够比较特异地标记神经分泌颗粒,具有确诊意义;神经特异性烯醇化酶染色20/20例阳性,非神经内分泌癌3/6例阳性,免疫电镜下无特异性分布,适宜作为诊断的筛选指标;S-100蛋白和5-HT亦可作为诊断之参考。 相似文献
105.
Vladimíra Džugasová Margita Obernauerová Katarína Horváthová Mariana Vachová Martina Žáková Július Šubík 《Current genetics》1998,34(4):297-302
The PEL1/PGS1 gene of the yeast Saccharomyces cerevisiae is essential for the viability of rho
–/rho° mutants and the normal cardiolipin content of cells. The PEL1-GFP fusion gene has been found to complement the pel1/pgs1 mutation and its fluorescent protein was localized to mitochondria similarly to the β-galactosidase activity of a protein encoded by the PEL1-lacZ fusion gene. The expression of the PEL1-lacZ reporter gene was repressed in cells grown in the presence of inositol and choline, reduced in the ino2 and ino4 strains, but constitutive in the opi1 null-mutant strain. The results demonstrate that Pel1p, playing a vital role in cells impaired in the mitochondrial DNA,
is localized in the mitochondria and expressed in response to inositol and choline.
Received: 15 June / 15 July 1998 相似文献
106.
I. TREBICHAVSKÝ F. KOVÁŘŮ V. STOŽICKÝ P. ŠIMAN 《American journal of reproductive immunology (New York, N.Y. : 1989)》1984,5(4):161-163
ABSTRACT: Placentomata of sheep immunized with human serum albumin (HSA) were examined. Both HSA and immunoglobulins were found in the maternal part and maternofetal border of the placenta using FITC labelled antisera on paraffin sections. Radiolabelled HSA was also detected in the fetal blood. The ultrastructure of placentomata revealed immunopathological process. 相似文献
107.
108.
Philip Avner Maja Bućan Danielle Arnaud Hans Lehrach Ulf Rapp 《Somatic Cell and Molecular Genetics》1987,13(3):267-272
The localization of the A-rafcellular oncogene on the mouse X chromosome has been determined using Xbal-restricted DNAs prepared from progeny of an interspecies backcross between the B6.CBA.R1 and the Spe/Pas mouse strains. This localization to the proximal part of the mouse X chromosome has been confirmed by the use of somatic cell hybrids, carrying partially deleted X chromosomes and suggests that the A-raf oncogene localizes to a region lying some 10–17 centimorgans proximal to the hypoxanthine phosphoribosyltransferase (Hprt) gene between the locus DXPas4and the locus DXPas7defined by the cross-reacting human X chromosome-specific probe DXS32 (M2C). This localization on the mouse X chromosome is compatible with the presence of the A-rafoncogene on the short arm of the human X chromosome between the centromere and Xp21. 相似文献
109.
The action of glycine on cortical neurones 总被引:12,自引:0,他引:12
110.