全文获取类型
收费全文 | 1813篇 |
免费 | 297篇 |
国内免费 | 40篇 |
专业分类
耳鼻咽喉 | 22篇 |
儿科学 | 103篇 |
妇产科学 | 23篇 |
基础医学 | 107篇 |
口腔科学 | 29篇 |
临床医学 | 288篇 |
内科学 | 592篇 |
皮肤病学 | 60篇 |
神经病学 | 180篇 |
特种医学 | 300篇 |
外科学 | 216篇 |
综合类 | 31篇 |
预防医学 | 69篇 |
眼科学 | 16篇 |
药学 | 57篇 |
中国医学 | 1篇 |
肿瘤学 | 56篇 |
出版年
2024年 | 9篇 |
2023年 | 52篇 |
2022年 | 13篇 |
2021年 | 27篇 |
2020年 | 92篇 |
2019年 | 17篇 |
2018年 | 90篇 |
2017年 | 71篇 |
2016年 | 70篇 |
2015年 | 61篇 |
2014年 | 95篇 |
2013年 | 111篇 |
2012年 | 47篇 |
2011年 | 42篇 |
2010年 | 80篇 |
2009年 | 112篇 |
2008年 | 48篇 |
2007年 | 49篇 |
2006年 | 44篇 |
2005年 | 30篇 |
2004年 | 14篇 |
2003年 | 23篇 |
2002年 | 21篇 |
2001年 | 34篇 |
2000年 | 16篇 |
1999年 | 24篇 |
1998年 | 81篇 |
1997年 | 95篇 |
1996年 | 78篇 |
1995年 | 68篇 |
1994年 | 49篇 |
1993年 | 52篇 |
1992年 | 29篇 |
1991年 | 24篇 |
1990年 | 32篇 |
1989年 | 58篇 |
1988年 | 44篇 |
1987年 | 32篇 |
1986年 | 26篇 |
1985年 | 23篇 |
1984年 | 18篇 |
1983年 | 11篇 |
1982年 | 14篇 |
1981年 | 14篇 |
1980年 | 15篇 |
1979年 | 8篇 |
1978年 | 8篇 |
1977年 | 10篇 |
1976年 | 10篇 |
1971年 | 9篇 |
排序方式: 共有2150条查询结果,搜索用时 15 毫秒
101.
Aung Myat MD Florence Mouy BMBS Luke Buckner BMBS James Cockburn MD Andreas Baumbach MD Philip MacCarthy PhD Adrian P. Banning MD Nick Curzen PhD Roland Hilling-Smith MD Daniel J. Blackman MD Michael Mullen MD Mark de Belder MD Ian Cox MD Jan Kovac MD Ganesh Manoharan MD Azfar Zaman MD Douglas Muir MBChB David Smith MD Stephen Brecker MD Mark Turner PhD Saib Khogali MD Iqbal S. Malik PhD Osama Alsanjari MRCP Francesca D'Auria PhD Simon Redwood MD Bernard Prendergast DM Uday Trivedi MD Derek Robinson DPhil Peter Ludman MD Adam de Belder MD David Hildick-Smith MD 《Catheterization and cardiovascular interventions》2021,98(3):E444-E452
102.
103.
104.
Phenotypic and functional characterization of T-BAM (CD40 ligand)+ T- cell non-Hodgkin's lymphoma 总被引:1,自引:0,他引:1
The precise mechanisms regulating T-helper function have been intensively investigated. We and others have recently identified a new T-cell-B-cell-activating molecule called T-BAM that directs B-cell differentiation by interacting with the CD40 molecule on B cells. Using a specific monoclonal antibody against T-BAM (5C8), we have previously shown that T-BAM expressing T cells are predominantly CD4+CD8- and in normal lymphoid tissue have a unique distribution. However, no information has been obtained regarding the phenotype and functional properties of human neoplastic T cells. Therefore, we investigated T- BAM expression immunohistochemically in 87 well-characterized T-cell non-Hodgkin's lymphomas and lymphoid leukemias (LL). We found that 21/81 neoplasms expressed detectable T-BAM and these positive tumors belong almost exclusively to the CD4+CD8- subtype. In addition, to determine whether T-BAM expression could be induced on T-BAM-LL cells, we activated T-BAM-LLs in vitro and showed that T-BAM could be upregulated only in CD4+CD8- tumors. Our studies clearly show that T- BAM is constitutively expressed in a large number of T-cell neoplasms with a relative mature phenotype (CD4+CD8-) and that only CD4+ neoplastic T cells can be induced in vitro to express this molecule. Additional studies are necessary to identify the biologic significance of T-BAM expression and its potential and clinical implications. 相似文献
105.
Platelet-derived growth factor (PDGF) is a potent mitogen for many cultured connective tissue cells. It is present in concentrated form within the platelet alpha-granules and is believed to be released during platelet degranulation at sites of vascular injury. We have used a sensitive radioreceptor assay to measure PDGF levels in whole blood serum from normal humans [17.5 +/- 3.1 (SD) ng/mL] and baboons (2.7 +/- 1.2 ng/mL). PDGF was not detected in plasma from either species. In addition, plasma was found to substantially reduce the ability of added purified PDGF to bind to the cell surface PDGF receptor on cultured cells, suggesting that plasma may contain a PDGF-binding protein that would serve to inactivate PDGF released into plasma. Calculations of PDGF concentrations in serum have been corrected for the effects of the binding protein. 125I-PDGF injected intravenously into normal baboons was cleared rapidly from the plasma (t1/2 = two minutes). The rapid clearance of 125I-PDGF did not result from iodination damage, as purified unlabeled PDGF was cleared with comparable kinetics. The rapid clearance of purified and iodinated PDGF did not result from changes in PDGF structure during purification or from removal of PDGF-associated proteins during purification, as PDGF present in freeze-thaw lysates of fresh platelets was cleared equally rapidly. We conclude that release of PDGF at sites of vascular injury would greatly increase the local concentration of PDGF and that PDGF not localized to the site of injury would be rapidly cleared from the circulation. 相似文献
106.
107.
Shalender Bhasin MB BS Thomas G. Travison PhD Todd M. Manini PhD Sheena Patel MS Karol M. Pencina PhD Roger A. Fielding PhD Jay M. Magaziner PhD Anne B. Newman MD MPH Douglas P. Kiel MD Cyrus Cooper DM FMedSci Jack M. Guralnik MD PhD Jane A. Cauley Dr.PH Hidenori Arai MD PhD Brian C. Clark PhD Francesco Landi MD PhD Laura A. Schaap PhD Suzette L. Pereira PhD Daniel Rooks PhD Jean Woo MD PhD Linda J. Woodhouse PhD Ellen Binder MD Todd Brown MD Michelle Shardell PhD Quian-Li Xue PhD Ralph B. DʼAgostino Sr PhD Denise Orwig PhD Greg Gorsicki PhD Rosaly Correa-De-Araujo MD PhD Peggy M. Cawthon PhD 《Journal of the American Geriatrics Society》2020,68(7):1410-1418
108.
109.
110.