全文获取类型
收费全文 | 96285篇 |
免费 | 6707篇 |
国内免费 | 3755篇 |
专业分类
耳鼻咽喉 | 363篇 |
儿科学 | 1650篇 |
妇产科学 | 984篇 |
基础医学 | 15237篇 |
口腔科学 | 1846篇 |
临床医学 | 7629篇 |
内科学 | 16077篇 |
皮肤病学 | 1123篇 |
神经病学 | 9371篇 |
特种医学 | 1469篇 |
外国民族医学 | 17篇 |
外科学 | 5459篇 |
综合类 | 15482篇 |
现状与发展 | 22篇 |
预防医学 | 5303篇 |
眼科学 | 1112篇 |
药学 | 13951篇 |
27篇 | |
中国医学 | 3541篇 |
肿瘤学 | 6084篇 |
出版年
2024年 | 1039篇 |
2023年 | 1421篇 |
2022年 | 2680篇 |
2021年 | 3533篇 |
2020年 | 2876篇 |
2019年 | 2463篇 |
2018年 | 2351篇 |
2017年 | 2635篇 |
2016年 | 2953篇 |
2015年 | 3330篇 |
2014年 | 5673篇 |
2013年 | 6465篇 |
2012年 | 6003篇 |
2011年 | 6724篇 |
2010年 | 5356篇 |
2009年 | 5135篇 |
2008年 | 5276篇 |
2007年 | 5026篇 |
2006年 | 4522篇 |
2005年 | 4246篇 |
2004年 | 3491篇 |
2003年 | 3045篇 |
2002年 | 2315篇 |
2001年 | 1968篇 |
2000年 | 1706篇 |
1999年 | 1472篇 |
1998年 | 1418篇 |
1997年 | 1292篇 |
1996年 | 1103篇 |
1995年 | 917篇 |
1994年 | 873篇 |
1993年 | 742篇 |
1992年 | 663篇 |
1991年 | 634篇 |
1990年 | 537篇 |
1989年 | 454篇 |
1988年 | 433篇 |
1987年 | 425篇 |
1986年 | 399篇 |
1985年 | 560篇 |
1984年 | 496篇 |
1983年 | 327篇 |
1982年 | 405篇 |
1981年 | 319篇 |
1980年 | 249篇 |
1979年 | 170篇 |
1978年 | 141篇 |
1977年 | 115篇 |
1976年 | 91篇 |
1975年 | 76篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Immunohistochemical analysis of centromere protein F expression in buccal and gingival squamous cell carcinoma 总被引:4,自引:0,他引:4
Centromere protein F (CENP-F) expression (localization and characteristics) in relation to tumor clinicopathological parameters was immunohistochemically examined and evaluated in 47 archival biopsy specimens of buccal and gingival squamous cell carcinomas (SCC). Centromere protein F expression was detected in 79% of the samples. An increase in the labeling index (LI) with WHO grading was obtained ( P < 0.05). Correlations were obtained between the CENP-F LI and tumor size ( P < 0.05). Immunoelectron microscopy showed CENP-F nuclear staining as punctate or fine dots. The present study shows that CENP-F expression and detection of a more specific cell subpopulation presents a theoretical advantage for the analysis of the precise cell cycle of G2 to M cells, compared to Ki-67. 相似文献
82.
83.
84.
Ethan A. Carver Kathleen F. Oram Thomas Gridley 《Anatomical record (Hoboken, N.J. : 2007)》2002,268(2):90-92
Saethre‐Chotzen syndrome is a common autosomal dominant form of craniosynostosis, the premature fusion of the sutures of the calvarial bones of the skull. Most Saethre‐Chotzen syndrome cases are caused by haploinsufficiency for the TWIST gene. Mice heterozygous for a null mutation of the Twist gene replicate certain features of Saethre‐Chotzen syndrome, but have not been reported to exhibit craniosynostosis. We demonstrate that Twist heterozygous mice exhibit fusions of the coronal suture and other cranial suture abnormalities, indicating that Twist heterozygous mice constitute a better animal model for Saethre‐Chotzen syndrome than was previously appreciated. Anat Rec 268:90–92, 2002. © 2002 Wiley‐Liss, Inc. 相似文献
85.
86.
Immunohistochemical study of neuron specific enolase and S-100 protein in Hirschsprung's disease 总被引:3,自引:0,他引:3
Tomoaki Taguchi Kenzo Tanaka Keiichi Ikeda 《Virchows Archiv : an international journal of pathology》1985,405(4):399-409
Summary The distribution of whole differentiated neurons in the intestines from 15 children with Hirschsprung's disease was investigated using neuron specific enolase (NSE) and the perineuronal elements were studied using S-100 protein immunostaining.In aganglionic segments, NSE immunoreactive ganglion cells and S-100 positive satellite cells were absent, but the hypertrophic nerve trunks did show a markedly positive NSE and S-100 immunoreactivity.Two different forms of aganglionic segment were present. One was the middle aganglionic segment of long segment aganglionosis which was almost completely dennervated. In the other type, there were several NSE positive nerve fibers in the muscularis propria of both the aganglionic segment of short segment aganglionosis and the distal aganglionic segment of long segment aganglionosis. These latter two aganglionic segments seemed to be innervated by extrinsic nerves. 相似文献
87.
Kirton CM Laukkanen ML Nieminen A Merinen M Stolen CM Armour K Smith DJ Salmi M Jalkanen S Clark MR 《European journal of immunology》2005,35(11):3119-3130
Human vascular adhesion protein-1 (VAP-1) is a homodimeric 170-kDa sialoglycoprotein that is expressed on the surface of endothelial cells and functions as a semicarbazide-sensitive amine oxidase and as an adhesion molecule. Blockade of VAP-1 has been shown to reduce leukocyte adhesion and transmigration in in vivo and in vitro models, suggesting that VAP-1 is a potential target for anti-inflammatory therapy. In this study we have constructed mouse-human chimeric antibodies by genetic engineering in order to circumvent the potential problems involved in using murine antibodies in man. Our chimeric anti-VAP-1 antibodies, which were designed to lack Fc-dependent effector functions, bound specifically to cell surface-expressed recombinant human VAP-1 and recognized VAP-1 in different cell types in tonsil. Furthermore, the chimeric antibodies prevented leukocyte adhesion and transmigration in vitro and in vivo. Hence, these chimeric antibodies have the potential to be used as a new anti-inflammatory therapy. 相似文献
88.
A protein, Vp130, that interacts with the host cell wall was isolated from Chlorovirus CVK2. From its peptide sequence, the gene for Vp130 was identified on the PBCV-1 genomic sequence as an ORF combining A140R and A145R. In Vp130, the N-terminus was somehow modified and the C-terminus was occupied by 23-26 tandem repeats of a PAPK motif. In the internal region, Vp130 contained seven repeats of 70-73 amino acids, each copy of which was separated by PAPK sequences. This protein was well conserved among NC64A viruses. A recombinant rVp130N protein formed in Escherichia coli was shown not only to bind directly to the host cell wall in vitro but also to specifically bind to the host cells, as demonstrated by fluorescence microscopy. Because externally added rVp130N competed with CVK2 to bind to host cells, Vp130 is most likely to be a host-recognizing protein on the virion. 相似文献
89.
We here report a molecular basis for downregulation of interferon (IFN)-beta production by V and C proteins of Sendai virus (SeV). The infection of HeLa cells with SeV poorly induced IFN-beta even if the expression of C/C' was disrupted. In contrast, when the expression of C/C'/Y1/Y2 or V/W was disrupted, SeV infection strongly induced IFN-beta production and significantly activated the interferon regulatory factor (IRF)-3 pathway. The independent expression of C or V inhibited the double-stranded (ds) RNA- or Newcastle disease virus (NDV)-induced activation of IRF-3 and NF-kappa B, as well as the IFN-beta promoter. This inhibitory effect was also observed when Y1, Y2, or a C-terminal half fragment (aa 85-204) of C was independently expressed. Phosphorylation and homodimer formation of IRF-3 were suppressed not only in cells infected with SeV capable of expressing both C/C'/Y1/Y2 (or Y1/Y2) and V/W, but also in HeLa cells constitutively expressing Y1. These results suggest that C, Y1, Y2, and V block signaling pathways leading to IRF-3 activation to downregulate IFN-beta production. 相似文献
90.