全文获取类型
收费全文 | 975篇 |
免费 | 73篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 20篇 |
儿科学 | 17篇 |
妇产科学 | 5篇 |
基础医学 | 139篇 |
口腔科学 | 2篇 |
临床医学 | 102篇 |
内科学 | 205篇 |
皮肤病学 | 24篇 |
神经病学 | 79篇 |
特种医学 | 25篇 |
外科学 | 109篇 |
综合类 | 9篇 |
一般理论 | 3篇 |
预防医学 | 71篇 |
眼科学 | 20篇 |
药学 | 73篇 |
肿瘤学 | 150篇 |
出版年
2024年 | 3篇 |
2023年 | 16篇 |
2022年 | 27篇 |
2021年 | 32篇 |
2020年 | 39篇 |
2019年 | 39篇 |
2018年 | 33篇 |
2017年 | 27篇 |
2016年 | 35篇 |
2015年 | 46篇 |
2014年 | 49篇 |
2013年 | 47篇 |
2012年 | 100篇 |
2011年 | 67篇 |
2010年 | 38篇 |
2009年 | 40篇 |
2008年 | 66篇 |
2007年 | 52篇 |
2006年 | 54篇 |
2005年 | 47篇 |
2004年 | 63篇 |
2003年 | 40篇 |
2002年 | 41篇 |
2001年 | 6篇 |
2000年 | 6篇 |
1999年 | 4篇 |
1998年 | 6篇 |
1997年 | 5篇 |
1996年 | 5篇 |
1995年 | 1篇 |
1993年 | 3篇 |
1992年 | 1篇 |
1991年 | 4篇 |
1989年 | 1篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 3篇 |
1978年 | 1篇 |
1975年 | 2篇 |
排序方式: 共有1053条查询结果,搜索用时 15 毫秒
31.
32.
Chua JJ Butkevich E Worseck JM Kittelmann M Grønborg M Behrmann E Stelzl U Pavlos NJ Lalowski MM Eimer S Wanker EE Klopfenstein DR Jahn R 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(15):5862-5867
Presynaptic nerve terminals are formed from preassembled vesicles that are delivered to the prospective synapse by kinesin-mediated axonal transport. However, precisely how the various cargoes are linked to the motor proteins remains unclear. Here, we report a transport complex linking syntaxin 1a (Stx) and Munc18, two proteins functioning in synaptic vesicle exocytosis at the presynaptic plasma membrane, to the motor protein Kinesin-1 via the kinesin adaptor FEZ1. Mutation of the FEZ1 ortholog UNC-76 in Caenorhabditis elegans causes defects in the axonal transport of Stx. We also show that binding of FEZ1 to Kinesin-1 and Munc18 is regulated by phosphorylation, with a conserved site (serine 58) being essential for binding. When expressed in C. elegans, wild-type but not phosphorylation-deficient FEZ1 (S58A) restored axonal transport of Stx. We conclude that FEZ1 operates as a kinesin adaptor for the transport of Stx, with cargo loading and unloading being regulated by protein kinases. 相似文献
33.
Nielsen ME Feechan A Böhlenius H Ueda T Thordal-Christensen H 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(28):11443-11448
Penetration resistance to powdery mildew fungi, conferred by localized cell wall appositions (papillae), is one of the best-studied processes in plant innate immunity. The syntaxin PENETRATION (PEN)1 is required for timely appearance of papillae, which contain callose and extracellular membrane material, as well as PEN1 itself. Appearance of membrane material in papillae suggests secretion of exosomes. These are potentially derived from multivesicular bodies (MVBs), supported by our observation that ARA6-labeled organelles assemble at the fungal attack site. However, the trafficking components that mediate delivery of extracellular membrane material are unknown. Here, we show that the delivery is independent of PEN1 function. Instead, we find that application of brefeldin (BF)A blocks the papillary accumulation of GFP-PEN1-labeled extracellular membrane and callose, while impeding penetration resistance. We subsequently provide evidence indicating that the responsible BFA-sensitive ADP ribosylation factor-GTP exchange factor (ARF-GEF) is GNOM. Firstly, analysis of the transheterozygote gnom(B4049/emb30-1) (gnom(B)(/E)) mutant revealed a delay in papilla formation and reduced penetration resistance. Furthermore, a BFA-resistant version of GNOM restored the BFA-sensitive papillary accumulation of GFP-PEN1 and callose. Our data, therefore, provide a link between GNOM and disease resistance. We suggest that papilla formation requires rapid reorganization of material from the plasma membrane mediated by GNOM. The papilla material is subsequently presumed to be sorted into MVBs and directed to the site of fungal attack, rendering the epidermal plant cell inaccessible for the invading powdery mildew fungus. 相似文献
34.
35.
36.
37.
38.
39.
Clinical features,exercise hemodynamics,and determinants of left ventricular elevated filling pressure in heart‐transplanted patients 下载免费PDF全文
Tor Skibsted Clemmensen Hans Eiskjær Brian Bridal Løgstrup Søren Mellemkjær Mads Jønsson Andersen Lars Poulsen Tolbod Hendrik J. Harms Steen Hvitfeldt Poulsen 《Transplant international》2016,29(2):196-206
This study aimed to assess clinical, functional, and hemodynamic characteristics of heart‐transplanted (HTX) patients during exercise. We performed comprehensive echocardiographic graft function assessment during invasive hemodynamic semi‐supine exercise test in 57 HTX patients. According to hemodynamics findings, patients were divided into Group A: normal left ventricular (LV) filling pressure (FP): pulmonary capillary wedge pressure (PCWP) <15 mmHg at rest and <25 mmHg at peak exercise, and Group B: elevated LV‐FP: PCWP ≥15 mmHg at rest or ≥25 mmHg at peak exercise. Thirty‐one patients (54%) had normal LV‐FP and 26 patients (46%) had elevated LV‐FP. The latter had higher cumulative rejection burden (P < 0.01) and were more symptomatic (NYHA class >1) (P < 0.05), and cardiac allograft vasculopathy (CAV) was more prevalent (P < 0.05). With exercise, the changes in both left‐ and right‐sided filling pressures were significantly increased, whereas LV longitudinal myocardial deformation was lower (P < 0.05) in patients with elevated LV‐FP than in patients with normal LV‐FP. No between‐group difference was observed for cardiac index or LV ejection fraction (LVEF) during exercise. In conclusion, elevated LV‐FP can be demonstrated in approximately 50% of HTX patients. Patients with elevated LV‐FP have impaired myocardial deformation capacity, higher prevalence of CAV, and higher rejection burden, and were more symptomatic. Exercise test with the assessment of longitudinal myocardial deformation should be considered in routine surveillance of HTX patients as a marker of restrictive filling (ClinicalTrials.gov Identifier: NCT02077764). 相似文献
40.