全文获取类型
收费全文 | 132篇 |
免费 | 1篇 |
国内免费 | 2篇 |
专业分类
化学 | 83篇 |
晶体学 | 2篇 |
数学 | 19篇 |
物理学 | 31篇 |
出版年
2022年 | 1篇 |
2021年 | 2篇 |
2020年 | 1篇 |
2019年 | 2篇 |
2018年 | 2篇 |
2017年 | 1篇 |
2016年 | 6篇 |
2015年 | 1篇 |
2014年 | 6篇 |
2013年 | 8篇 |
2012年 | 15篇 |
2011年 | 8篇 |
2010年 | 7篇 |
2009年 | 6篇 |
2008年 | 8篇 |
2007年 | 5篇 |
2006年 | 5篇 |
2005年 | 2篇 |
2004年 | 4篇 |
2003年 | 1篇 |
2002年 | 6篇 |
2001年 | 2篇 |
1999年 | 4篇 |
1998年 | 4篇 |
1997年 | 4篇 |
1996年 | 2篇 |
1995年 | 1篇 |
1994年 | 2篇 |
1993年 | 2篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1983年 | 1篇 |
1982年 | 3篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1976年 | 1篇 |
1975年 | 2篇 |
1971年 | 1篇 |
1970年 | 1篇 |
排序方式: 共有135条查询结果,搜索用时 46 毫秒
131.
An IR absorption band with a maximum beyond 2400 nm has been found and assigned to the electron in the following systems irradiated at 76 K: crystalline D2O, and D2O glasses of ethylene glycol, MgCl2 and LiCl. The band is tentatively attributed to an electron captured in a D-defect. 相似文献
132.
Rademacher C Shoemaker GK Kim HS Zheng RB Taha H Liu C Nacario RC Schriemer DC Klassen JS Peters T Lowary TL 《Journal of the American Chemical Society》2007,129(34):10489-10502
The CS-35 antibody is widely used in the characterization of glycans containing D-arabinofuranose residues, in particular polysaccharides present in the mycobacterial cell wall. A detailed understanding of the combining site of this antibody and the measurement of its binding to different ligands is of interest as this knowledge will have implications in the characterization of arabinofuranose-containing glycoconjugates that are increasingly recognized as important biological molecules. Of even greater significance is that an in-depth study of this carbohydrate-protein interaction will provide insights into the mechanisms by which oligosaccharides containing furanose rings are bound by proteins, an area that has, to date, received little attention. This system has been refractory to X-ray crystallography, and thus we report here a study of the interaction of CS-35 with its ligands using a combination of chemical synthesis, mass spectrometry, titration microcalorimetry, and NMR spectroscopy. Through these investigations we have established that the binding pocket recognizes, as a minimum epitope, a linear tetrasaccharide motif and that the residues at the reducing and non-reducing end of the oligosaccharide are essential for tight binding. The residue at the non-reducing end appears to be bound in an aliphatic pocket, whereas the rest of the tetrasaccharide interacts more strongly with aromatic amino acids. 相似文献
133.
Lu Deng Elena N. Kitova John S. Klassen 《Journal of the American Society for Mass Spectrometry》2013,24(7):988-996
Intermolecular interactions in the gaseous ions of two protein–ligand complexes, a single chain antibody (scFv) and its trisaccharide ligand (α-D-Galp-(1→2)-[α-D-Abep-(1→3)]-α-Manp-OCH3, L1) and streptavidin homotetramer (S4) and biotin (B), were investigated using a collision-induced dissociation (CID)-functional group replacement (FGR) strategy. CID was performed on protonated ions of a series of structurally related complexes based on the (scFv + L1) and (S4?+?4B) complexes, at the +10 and +13 charge states, respectively. Intermolecular interactions were identified from decreases in the collision energy required to dissociate 50 % of the reactant ion (Ec50) upon modification of protein residues or ligand functional groups. For the (scFv + L1)10+ ion, it was found that deoxygenation of L1 (at Gal C3 and C6 and Man C4 and C6) or mutation of His101 (to Ala) resulted in a decrease in Ec50 values. These results suggest that the four hydroxyl groups and His101 participate in intermolecular H-bonds. These findings agree with those obtained using the blackbody infrared radiative dissociation (BIRD)-FGR method. However, the CID-FGR method failed to reveal the relative strengths of the intermolecular interactions or establish Man C4 OH and His101 as an H-bond donor/acceptor pair. The CID-FGR method correctly identified Tyr43, but not Ser27, Trp79, and Trp120, as a stabilizing contact in the (S4?+?4B)13+ ion. In fact, mutation of Trp79 and Trp120 led to an increase in the Ec50 value. Taken together, these results suggest that the CID-FGR method, as implemented here, does not represent a reliable approach for identifying interactions in the gaseous protein–ligand complexes. 相似文献
134.
Liu L Kitova EN Klassen JS 《Journal of the American Society for Mass Spectrometry》2011,22(2):310-318
The application of the direct electrospray ionization mass spectrometry (ESI-MS) assay to quantify interactions between bovine
β-lactoglobulin (Lg) and a series of fatty acids (FA), CH3(CH2)xCOOH, where x = 6 (caprylic acid, CpA), 8 (capric acid, CA), 10 (lauric acid, LA), 12 (myristic acid, MA), 14 (palmitic acid,
PA) and 16 (stearic acid, SA), is described. Control ESI-MS binding measurements performed on the Lg-PA interaction revealed
that both the protonated and deprotonated gas phase ions of the (Lg + PA) complex are prone to dissociate in the ion source,
which leads to artificially small association constants (K
a
). The addition of imidazole, a stabilizing solution additive, at high concentration (10 mM) increased the relative abundance
of (Lg + PA) complex measured by ESI-MS in both positive and negative ion modes. The K
a
value measured in negative ion mode and using sampling conditions that minimize in-source dissociation is in good agreement
with a value determined using a competitive fluorescence assay. The K
a
values measured by ESI-MS for the Lg interactions with MA and SA are also consistent with values expected based on the fluorescence
measurements. However, the K
a
values measured using optimal sampling conditions in positive ion mode are significantly lower than those measured in negative
ion mode for all of the FAs investigated. It is concluded that the protonated gaseous ions of the (Lg + FA) complexes are
kinetically less stable than the deprotonated ions. In-source dissociation was significant for the complexes of Lg with the
shorter FAs (CpA, CA, and LA) in both modes and, in the case of CpA, no binding could be detected by ESI-MS. The affinities
of Lg for CpA, CA, and LA determined using the reference ligand ESI-MS assay, a method for quantifying labile protein–ligand
complexes that are prone to in-source dissociation, were found to be in good agreement with reported values. 相似文献
135.
Ou Jin Yuanyuan Shang Xiaohui Huang Dorothe Vinga Szab Thi Thu Le Stefan Wagner Thomas Klassen Christian Kübel Claudio Pistidda Astrid Pundt 《Molecules (Basel, Switzerland)》2022,27(20)
The reactive hydride composite (RHC) LiBH4–MgH2 is regarded as one of the most promising materials for hydrogen storage. Its extensive application is so far limited by its poor dehydrogenation kinetics, due to the hampered nucleation and growth process of MgB2. Nevertheless, the poor kinetics can be improved by additives. This work studied the growth process of MgB2 with varying contents of 3TiCl3·AlCl3 as an additive, and combined kinetic measurements, X-ray diffraction (XRD), and advanced transmission electron microscopy (TEM) to develop a structural understanding. It was found that the formation of MgB2 preferentially occurs on TiB2 nanoparticles. The major reason for this is that the elastic strain energy density can be reduced to ~4.7 × 107 J/m3 by creating an interface between MgB2 and TiB2, as opposed to ~2.9 × 108 J/m3 at the original interface between MgB2 and Mg. The kinetics of the MgB2 growth was modeled by the Johnson–Mehl–Avrami–Kolmogorov (JMAK) equation, describing the kinetics better than other kinetic models. It is suggested that the MgB2 growth rate-controlling step is changed from interface- to diffusion-controlled when the nucleation center changes from Mg to TiB2. This transition is also reflected in the change of the MgB2 morphology from bar- to platelet-like. Based on our observations, we suggest that an additive content between 2.5 and 5 mol% 3TiCl3·AlCl3 results in the best enhancement of the dehydrogenation kinetics. 相似文献