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61.
Korzhavyi PA Soroka IL Isaev EI Lilja C Johansson B 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(3):686-689
New important applications of copper metal, e.g., in the areas of hydrogen production, fuel cell operation, and spent nuclear fuel disposal, require accurate knowledge of the physical and chemical properties of stable and metastable copper compounds. Among the copper(I) compounds with oxygen and hydrogen, cuprous oxide Cu(2)O is the only one stable and the best studied. Other such compounds are less known (CuH) or totally unknown (CuOH) due to their instability relative to the oxide. Here we combine quantum-mechanical calculations with experimental studies to search for possible compounds of monovalent copper. Cuprous hydride (CuH) and cuprous hydroxide (CuOH) are proved to exist in solid form. We establish the chemical and physical properties of these compounds, thereby filling the existing gaps in our understanding of hydrogen- and oxygen-related phenomena in Cu metal. 相似文献
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Bruha R Vitek L Marecek Z Pospisilova L Nevsimalova S Martasek P Petrtyl J Urbanek P Jiraskova A Malikova I Haluzik M Ferenci P 《Journal of inherited metabolic disease》2012,35(3):541-548
Background &; Aims
Wilson disease (WD) is an inherited disorder of copper disposition caused by an ATP7B transporter gene mutation, leading to copper accumulation in predisposed tissues. In addition to a genetic predisposition, other factors are likely to contribute to its clinical manifestation. The aim of the study was to assess whether oxidative stress affects the phenotypic manifestation of WD.Methods
In 56 patients with WD (29 men; 26 with the hepatic form, 22 with the neurologic form, and eight asymptomatic; mean age 38.5?±?12 years), total serum antioxidant capacity (TAC) and inflammatory parameters (hs-CRP, IL-1??, IL-2, IL-6, IL-10, and TNF-??) were analyzed and related to the clinical manifestation, and mutations of the ATP7B gene. The control group for the TAC and inflammatory parameters consisted of 50 age- and gender-matched healthy individuals.Results
WD patients had a significantly lower TAC (p?0.00001), lower IL-10 levels (p?=?0.039), as well as both higher IL-1?? (p?=?0.019) and IL-6 (p?=?0.005) levels compared to the control subjects. TNF-??, hs-CRP, and IL-2 did not differ from the controls. Patients with the neurological form of WD had a significantly lower TAC than those with the hepatic form (p?0.001). In addition, the lower TAC was associated with the severity of the neurological symptoms (p?=?0.02). No relationship between the inflammatory parameters and clinical symptoms was found.Conclusions
Data from our study suggest that the increased oxidative stress contributes significantly to the clinical manifestation of WD; as a lower TAC is associated with the neurological symptoms in WD patients. 相似文献64.
65.
Jansa P Becvar R Ambroz D Palecek T Tomcik M Skacelova S Aschermann M Linhart A 《Clinical rheumatology》2012,31(3):557-561
Background
Systemic sclerosis (SSc) is an important cause of pulmonary arterial hypertension (PAH), with an estimated prevalence of 7.85–26.7%. 相似文献66.
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Miron Bugakov Sharifa Abdullaeva Pavel Samokhvalov Sergey Abramchuk Valery Shibaev Natalia Boiko 《RSC advances》2020,10(26):15264
Hybrid fluorescent liquid crystalline (LC) composites containing inorganic quantum dots (QDs) are promising materials for many applications in optics, nanophotonics and display technology, combining the superior emission capability of QDs with the externally controllable optical properties of LCs. In this work, we propose the hybrid LC composites that were obtained by embedding CdSe/ZnS QDs into a series of host LC block copolymers of different architectures by means of a two-stage ligand exchange procedure. The ABA/BAB triblock copolymers and AB diblock copolymers with different polymerization degrees are composed of nematogenic phenyl benzoate acrylic monomer units and poly(4-vinylpyridine) blocks, which are capable of binding to the QD surface. Our results clearly show that the spatial distribution of QDs within composite films as well as the formation of QD aggregates can be programed by varying the structure of the host block copolymer. The obtained composites form a nematic LC phase, with isotropization temperatures being close to those of the initial host block copolymers. In addition, the influence of the molecular architecture of the host block copolymers on fluorescence properties of the obtained composites is considered. The described strategy for the QD assembly should provide a robust and conventional route for the design of highly ordered hierarchical hybrid materials for many practical applications.Spatial distribution of QDs within hybrid composite films was programed by varying the molecular architecture of the host LC block copolymers. 相似文献