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931.
Agkisacutacin isolated from the venom of Agkistrodon acutus is a coagulation factor IX / coagulation factor X-binding protein with marked anticoagulant- and platelet-modulating activities.
Ca2+ ion-induced stabilization and refolding of Agkisacutacin have been studied by following fluorescent measurements. Ca2+ ions not only increase the structural stability of agkisacutacin against GdnHCl denaturation, but also induce its refolding.
The GdnHCl-induced unfolding of the apo-agkisacutacin and the purified agkisacutacin is a single-step process with no detectable
intermediate state. Ca2+ ions play an important role in the stabilization of the structure of agkisacutacin. Ca2+-stabilized agkisacutacin exhibits higher resistance to GdnHCl denaturation than the apo-agkisacutacin. It is possible to
induce refolding of the unfolded apo-agkisacutacin merely by adding 1 mM Ca2+ ions without changing the concentration of the denaturant. The kinetic result of Ca2+-induced refolding provides evidences for that agkisacutacin consists of at least two refolding phases and the first phase
of Ca2+-induced refolding should involve the formation of the compact Ca2+-binding site regions, and subsequently, the protein undergoes further conformational rearrangements to form the native structure. 相似文献
932.
"使用Brenner-LJ拟合势描述了金刚石与C36团簇原子间的相互作用,并用分子动力学模拟的方法研究单个C36(D6h)在金刚石(100)晶面的沉积机制.通过仿真实验分析了C36团簇的入射能量、入射点位置、入射姿势、入射角度等因素对其成核初期化学吸附过程以及沉积后其稳定性的影响.研究发现:由于C36入射点位置及入射姿势的不同,其在金刚石(100)晶面沉积时的沉积阈值最小值为20 eV,最大值为60 eV;在入射角不超过60o斜射时,由于水平运动分量的存在,C36可能翻滚及平滑至成键能量较小的区域后再成键 相似文献
933.
Chromatographia - In this study, a poly(glycidyl methacrylate) nanoparticle (PGMA NP)-coated column system with two antibiotics as selector was constructed for enantioseparation. The PGMA NP... 相似文献
934.
Chemistry of Natural Compounds - A new seco-abietanoid, 12-hydroxy-6,7-seco-abieta-8,11,13-triene-6,7-dioic acid (1), was isolated from the methanol extract of the bark of Cryptomeria japonica. The... 相似文献
935.
Transition Metal Chemistry - A Cu(II) coordination polymer, [Cu2(pztrz)2(μ-CH3COO)(CH3COO)]·3H2O (1), derived from mono-substituted 1,2,4-triazole derivative 3-(pyrazinyl)-1,2,4-triazole... 相似文献
936.
Li Chao Yin Siyu Zhou Hongbo Zhang Yajiao Li Yongxiu Chen Yufeng 《Journal of Sol-Gel Science and Technology》2021,99(2):430-443
Journal of Sol-Gel Science and Technology - A drug delivery system with near-infrared emissions response to drug delivery and release is essential as marking or targeting drug delivery system. For... 相似文献
937.
Saipeng?Huang Zhao?Chen Libo?Du Qiu?Tian Yangping?Liu Yuansuo?Zheng Yang?LiuEmail author 《Applied magnetic resonance》2015,46(5):489-504
The detection of free radicals and related species has attracted considerable attention in recent years due to their critical roles in physiological and pathological processes. Among the various methods for the detection of free radicals, electron spin resonance coupled with spin-trapping technique has been an effective approach for the characterization and quantification of free radicals due to its high specificity. In this study, we designed and synthesized a novel amphiphilic spin trap, 2-(diethoxyphosphoryl)-2-heptadecanyl-3,4-dihydro-2H-pyrrole-1-oxide (DEPHdPO), from 5-(diethoxyphosphoryl)-5-methyl-1-pyrroline-N-oxide with a long hydrocarbon chain at the C-5 position of the pyrroline ring, providing the amphiphilic character. The free-radical-trapping ability of DEPHdPO was evaluated by capturing hydroxyl radicals (·OH), superoxide anions (\( {\text{O}}_{2}^{ \cdot - } \)), and carbon-centered free radicals in a model membrane prepared from sodium dodecyl sulfate (SDS). The results indicate that the hydrophobic hydrocarbon chain of DEPHdPO can be inserted into the inner core of SDS micelles, and the hydrophilic nitronyl functional moiety is located on the surface layer. Thus, various free radicals, including ·OH radicals, \( {\text{O}}_{2}^{ \cdot - } \) anions, and carbon-centered radicals could be site-specifically detected near the membrane surface. Moreover, DEPHdPO could be successfully located on the surface of thylakoid membranes, and the nearby photo-initiated \( {\text{O}}_{2}^{ \cdot - } \) anions could be trapped site-specifically. 相似文献
938.
939.
940.
Ionics - In this paper, the simultaneous determination of β-blockers (atenolol (ATN) and propranolol (PRO)) was investigated using cyclic voltammetry (CV) and differential pulse voltammetry... 相似文献