全文获取类型
收费全文 | 5210篇 |
免费 | 459篇 |
国内免费 | 3篇 |
专业分类
5672篇 |
出版年
2024年 | 3篇 |
2023年 | 24篇 |
2022年 | 52篇 |
2021年 | 100篇 |
2020年 | 65篇 |
2019年 | 51篇 |
2018年 | 77篇 |
2017年 | 68篇 |
2016年 | 124篇 |
2015年 | 234篇 |
2014年 | 272篇 |
2013年 | 347篇 |
2012年 | 426篇 |
2011年 | 430篇 |
2010年 | 281篇 |
2009年 | 265篇 |
2008年 | 331篇 |
2007年 | 353篇 |
2006年 | 353篇 |
2005年 | 345篇 |
2004年 | 305篇 |
2003年 | 338篇 |
2002年 | 297篇 |
2001年 | 46篇 |
2000年 | 31篇 |
1999年 | 54篇 |
1998年 | 71篇 |
1997年 | 43篇 |
1996年 | 43篇 |
1995年 | 32篇 |
1994年 | 34篇 |
1993年 | 29篇 |
1992年 | 26篇 |
1991年 | 21篇 |
1990年 | 14篇 |
1989年 | 12篇 |
1988年 | 5篇 |
1987年 | 9篇 |
1986年 | 11篇 |
1985年 | 9篇 |
1984年 | 8篇 |
1983年 | 3篇 |
1982年 | 5篇 |
1981年 | 4篇 |
1979年 | 5篇 |
1978年 | 6篇 |
1973年 | 4篇 |
1972年 | 1篇 |
1966年 | 1篇 |
1936年 | 1篇 |
排序方式: 共有5672条查询结果,搜索用时 15 毫秒
51.
Hernout O Berthoin K Delattre I Tulkens PM Carryn S Marchand-Brynaert J 《Bioorganic & medicinal chemistry letters》2007,17(21):5758-5762
Four small molecular receptors of vancomycin have been designed to make part of a novel biosensor device based on the FTIR-ATR detection: N-Boc (2a) or N-Ac (2b)-6-aminocaproyl-D-Ala-D-Ala and N-Boc (3a) or N-Ac (3b)-6-aminocaproyl-D-Ala-d-Ser. Using an original microbiological approach to assess the competition of compounds with the natural target of vancomycin in bacteria, EC(50) values of 6.3-8.0 x 10(-5)M (2a-b) and 7.1-9.3 x 10(-4)M (3a-b) were determined. Vancomycin:2b complex was characterized by MS. 相似文献
52.
53.
54.
Early events of apoptosis following HSV-1 infection were investigated at the single-cell level using intensified fluorescence digital-imaging microscopy. The results provide evidence that infection of differentiated ND7 neuronlike cells by HSV-1 triggers detectable alterations indicative of physiological changes associated with the early stages of apoptosis. Less than 1 h after infection with HSV-1 (KOS strain) or K26GFP (GFP being fused to HSV-1 capsid protein VP26) we observed (i) moderate decrease in mitochondrial membrane potential (about 20%), (ii) exposure of phosphatidyl serine, (iii) morphological change in the mitochondria that became spherical instead of filamentous, and (iv) activation of caspase-8. Within 3 h changes reverted to normal, which indicated that apoptosis was counteracted very early following HSV-1 infection. Similar results were obtained with KOS-TK27GFP, lacking TK and UL24 proteins, suggesting that TK and UL24 play no role in apoptosis. In Vero cells mitochondrial changes characteristic of the apoptotic process were not observed following HSV-1 infection. The UV-inactivated K26GFP had the capacity to induce apoptosis in neuronlike cells. This real-time multiparametric analysis, in combination with relevant viral mutants, could be a useful approach for dissecting the roles of various viral genes in modulating apoptotic pathways during infection. 相似文献
55.
56.
57.
Roger Miras Isabelle Morin Florent Guillain Elisabeth Mintz 《Journal of biological inorganic chemistry》2008,13(2):195-205
Copper is both an essential element as a catalytic cofactor and a toxic element because of its redox properties. Once in the
cell, Cu(I) binds to glutathione (GSH) and various thiol-rich proteins that sequester and/or exchange copper with other intracellular
components. Among them, the Cu(I) chaperone Atx1 is known to deliver Cu(I) to Ccc2, the Golgi Cu–ATPase, in yeast. However,
the mechanism for Cu(I) incorporation into Atx1 has not yet been unraveled. We investigated here a possible role of GSH in
Cu(I) binding to Atx1. Yeast Atx1 was expressed in Escherichia coli and purified to study its ability to bind Cu(I). We found that with an excess of GSH [at least two GSH/Cu(I)], Atx1 formed
a Cu(I)-bridged dimer of high affinity for Cu(I), containing two Cu(I) and two GSH, whereas no dimer was observed in the absence
of GSH. The stability constants (log β) of the Cu(I) complexes measured at pH 6 were 15–16 and 49–50 for CuAtx1 and Cu2I(GS−)2(Atx1)2, respectively. Hence, these results suggest that in vivo the high GSH concentration favors Atx1 dimerization and that Cu2I(GS−)2(Atx1)2 is the major conformation of Atx1 in the cytosol. 相似文献
58.
59.
60.
Cedric Moro Isabelle Harant Pierre-Marie Badin François-Xavier Patarca Jean-Claude Guilland Virginie Bourlier Dominique Langin Isabelle De Glisezinski 《Journal of physiology and biochemistry》2014,70(2):583-591
The aim of the present study was to investigate the influence of substrate availability on fuel selection during exercise. Eight endurance-trained male cyclists performed 90-min exercise at 70 % of their maximal oxygen uptake in a cross-over design, either in rested condition (CON) or the day after 2-h exercise practised at 70 % of maximal oxygen uptake (EX). Subjects were given a sucrose load (0.75 g kg?1 body weight) 45 min after the beginning of the 90-min exercise test. Lipolysis was measured in subcutaneous abdominal adipose tissue (SCAT) by microdialysis and substrate oxidation by indirect calorimetry. Lipid oxidation increased during exercise and tended to decrease during sucrose ingestion in both conditions. Lipid oxidation was higher during the whole experimental period in the EX group (p?=?0.004). Interestingly, fuel selection, assessed by the change in respiratory exchange ratio (RER), was increased in the EX session (p?=?0.002). This was paralleled by a higher rate of SCAT lipolysis reflected by dialysate glycerol, plasma glycerol, and fatty acids (FA) levels (p?<?0.001). Of note, we observed a significant relationship between whole-body fat oxidation and dialysate glycerol in both sessions (r 2?=?0.33, p?=?0.02). In conclusion, this study highlights the limiting role of lipolysis and plasma FA availability to whole-body fat oxidation during exercise in endurance-trained subjects. This study shows that adipose tissue lipolysis is a determinant of fuel selection during exercise in healthy subjects. 相似文献