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排序方式: 共有3224条查询结果,搜索用时 31 毫秒
41.
Sofia Tikhanova Anna Seroglazova Maria Chebanenko Vladimir Nevedomskiy Vadim Popkov 《Materials》2022,15(22)
Nanostructured hexagonal rare-earth orthoferrites (h-RfeO3, R = Sc, Y, Tb-Lu) are well known as a highly effective base for visible-light-driven heterojunction photocatalysts. However, their application is limited by metastability, leading to difficulties in synthesis due to the irreversible transformation to a stable orthorhombic structure. In this work, we report on a simple route to the stabilization of h-YbFeO3 nanocrystals by the synthesis of multiphase nanocomposites with titania additives. The new I-type heterojunction nanocomposites of o-YbFeO3/h-YbFeO3/r-TiO2 were obtained by the glycine–nitrate solution combustion method with subsequent heat treatment of the products. An increase in the mole fraction of the h-YbFeO3 phase in nanocomposites was found with the titanium addition, indicating its stabilizing effect via limiting mass transfer over heat treatment. The complex physicochemical analysis shows multiple contacts of individual nanocrystals of o-YbFeO3 (44.4–50.6 nm), h-YbFeO3 (7.5–17.6 nm), and rutile r-TiO2 (~5 nm), confirming the presence of the heterojunction structure in the obtained nanocomposite. The photocatalytic activity of h-YbFeO3/o-YbFeO3/r-TiO2 nanocomposites was evaluated by the photo-Fenton degradation of the methyl violet under visible light (λ ≥ 400 nm). It was demonstrated that the addition of 5 mol.% of TiO2 stabilizes h-YbFeO3, which allowed us to achieve a 41.5 mol% fraction, followed by a three-time increase in the photodecomposition rate constant up to 0.0160 min−1. 相似文献
42.
Cristina Hidalgo-Moyano Oriol Alberto Rangel-Zuiga Francisco Gomez-Delgado Juan F. Alcala-Diaz Fernando Rodriguez-Cantalejo Elena M. Yubero-Serrano Jose D. Torres-Pea Antonio P. Arenas-de Larriva Antonio Camargo Pablo Perez-Martinez Jose Lopez-Miranda Javier Delgado-Lista 《Nutrients》2022,14(18)
We investigated whether long-term consumption of two healthy diets (low-fat (LF) or Mediterranean (Med)) interacts with SIRT1 genotypes to modulate aging-related processes such as leucocyte telomere length (LTL), oxidative stress (OxS) and inflammation in patients with coronary heart disease (CHD). LTL, inflammation, OxS markers (at baseline and after 4 years of follow-up) and SIRT1-Single Nucleotide Polymorphisms (SNPs) (rs7069102 and rs1885472) were determined in patients from the CORDIOPREV study. We analyzed the genotype-marker interactions and the effect of diet on these interactions. Regardless of the diet, we observed LTL maintenance in GG-carriers for the rs7069102, in contrast to carriers of the minor C allele, where it decreased after follow-up (p = 0.001). The GG-carriers showed an increase in reduced/oxidized glutathione (GSH/GSSG) ratio (p = 0.003), lower lipid peroxidation products (LPO) levels (p < 0.001) and a greater decrease in tumor necrosis factor-alpha (TNF-α) levels (p < 0.001) after follow-up. After the LF diet intervention, the GG-carriers showed stabilization in LTL which was significant compared to the C allele subjects (p = 0.037), although the protective effects found for inflammation and OxS markers remained significant after follow-up with the two diets. Patients who are homozygous for the SIRT1-SNP rs7069102 (the most common genotype) may benefit from healthy diets, as suggested by improvements in OxS and inflammation in patients with CHD, which may indicate the slowing-down of the aging process and its related diseases. 相似文献
43.
目的 探讨以护士为主导的多学科团队协作(MDT)延续护理模式在寻常型银屑病患者中的应用效果。方法 选取2019年12月至2020年12月在南方医科大学皮肤病医院银屑病病区接受治疗的96例寻常型银屑病患者,随机分为试验组与对照组,各48例。对照组患者出院后采用以护士主导的传统延续护理模式,试验组患者出院后采用以护士为主导、药师和临床医师共同参与的MDT延续护理模式,随访至出院后6个月,调查两组患者出院时皮损面积和严重程度指数(PASI)、疾病复发率、药物使用依从性、疾病相关知识掌握程度和生活质量。结果 出院后6个月,试验组患者较对照组患者PASI评分更低(3.87±1.82比6.43±2.57,t=7.87,P<0.01),疾病复发率更低(10.42%比33.33%,χ2=7.38,P=0.007),药物使用依从性(83.33%比16.67%,χ2=42.67,P<0.05)、疾病相关知识掌握程度(55.13±4.50比47.27±4.37,t=8.68,P<0.01)及生活质量更高(7.67±3.52比10.11±4.21,... 相似文献
44.
目的:观察大黄煎剂保留灌肠联合西药治疗肝性脑病疗效。方法:使用随机平行对照方法,将164例住院患者按抽签方法随机分为两组,对照组62例,给予西医综合治疗。治疗组102例,加用大黄煎剂(醋大黄30 g,乌梅30 g,川朴15 g)水煎200 mL,2剂/d,早晚灌肠,西药治疗同对照组。均连续治疗7 d为1个疗程。观察临床症状,苏醒时间,扑翼样震颤消失时间,血氨水平,肝功能指标,数字连接实验(NCT)及SF-36生活质量表。连续治疗1疗程,判定疗效。结果:治疗组显效54例,有效40例,无效8例,总有效率92.16%。对照组显效27例,有效23例,无效12例,总有效率80.65%。治疗组疗效优于对照组(P<0.05);治疗组的苏醒时间和扑翼样震颤消失时间明显短于对照组(P<0.05);血氨及肝功能两组均有改善(P<0.01),治疗组改善优于对照组(P<0.01,P<0.05);NCT及SF-36生活质量表评分两组均有改善(P<0.01,P<0.05),治疗组改善优于对照组(P<0.05)。均无明显不良反应。结论:大黄煎剂灌肠联合西药治疗肝性脑病疗效显著,值得推广。 相似文献
45.
Garry Kerch 《Nanomedicine : nanotechnology, biology, and medicine》2018,14(1):13-25
The direct and indirect (by changing mechanical properties) effects of hydration at interfaces on cellular processes and tissue diseases are reviewed. The essential effect of substrate stiffness on cellular processes was demonstrated in the last decade. The combined effect of surface stiffness and hydration at interfaces has garnered much less attention, though hydration and dehydration play important roles in biological processes. This review focuses on the studies that demonstrate how hydration affects biological processes at interfaces. Elevated sodium and dehydration stimulate inflammatory signaling in endothelial cells and promote atherosclerosis. Various types of implant and blood contacting device coatings with varied surface stiffness and hydration have been reported. Effect of hydration on polymer modulus of elasticity and viscoelasticity was discussed taking into account cells adhesion, migration, proliferation, differentiation on surfaces with various degree of hydration. Future directions of research were considered, including the use of nanotechnology to regulate the hydration degree. 相似文献
46.
摘 要 目的:建立一测多评(QAMS)法测定六味五灵片中连翘苷、五味子醇甲、五味子酯甲、五味子甲素、五味子乙素和五味子丙素等6种有效成分的含量,验证该方法在制剂中应用的准确性和可行性。方法: 采用HPCL法,在230nm检测波长下建立五味子甲素与五味子乙素、五味子丙素、五味子酯甲、五味子醇甲和连翘苷的相对校正因子(f),计算六味五灵片中各成分的含量,实现一测多评。同时采用外标法测定,并计算QAMS法含量计算结果(Wf)和外标法含量测定结果(Ws)的相对误差,验证一测多评法的准确性,并对其重现性进行考察。结果: 建立用于测定六味五灵片中6种成分含量的QAMS法,并对10批制剂中六味五灵片的指标成分进行测定,其计算值与测定值的差异较小(RSD<5%)。结论:QAMS法用于测六味五灵片6种有效成分的含量,方法简单、有效、结果准确。QAMS法测六味五灵片的质量评价模式得到了验证,可用于六味五灵片的质量控制,并为后续的一测多评的研究提供参考价值。 相似文献
47.
介绍多目标优化技术在中药复方药物筛选及组方优化中的应用,阐述了多目标优化技术在中药复方研究应用的思路与方法。其方案是以均匀设计法安排实验,综合主要目标法、虚拟目标法和约束条件法等多目标优化方法,以网格法作为优化算法实现复方药物筛选及优化,使多项药效指标都达到较好的平衡,从而取得最佳复方配伍组合。本研究探索建立的基于均匀设计的多目标优化技术在药物复方研究中的应用,有助于解决中药复方药物配伍研究方法的关键技术问题,有助于释放出中药复方中潜在的巨大经济效益。 相似文献
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