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61.
Hui Tang Can-Hui Zheng Xiao-Hui Ren Jia Liu Na Liu Jia-Guo Lv Ju Zhu You-Jun Zhou 《中国化学快报》2013,24(3):219-222
A series of 1-(benzylamino)-2-(2,4-difluorophenyl)-3-(1H-1,2,4-triazol-l-yl)propan-2-ols compounds were synthesized and evaluated for their antifungal activities in vitro.The results showed that compounds 6A and 6B exhibited good antifungal activity.Compound 6A8 showed the strongest antifungal activity,which was significantly higher than that of the lead compounds and positive-control drugs Fluconazole and Itraconazole.In particular,the antifungal activity of compound 6A8 against Candida albicans and Candida krusei(MIC80 both at 0.00097μg/mL) was 515 and 64 times that of Fluconazole,respectively.The structure-activity relationships of the synthesized compounds were discussed,and the docking model of the target compounds with fungal lanosterol 14α-demethylase (CYP51) was analyzed. 相似文献
62.
Siburg and Stoimenov [12] gave a measure of mutual complete dependence of continuous variables which is different from Spearman's ρ and Kendall's τ. In this paper, a similar measure of mutual complete dependence is applied to discrete variables. Also two measures for functional relationships, which are not bijection, are investigated. For illustration of our main results, several examples are given. 相似文献
63.
A methodology for classifying the hierarchy of martensite boundaries from the EBSD microtexture data of low-carbon steel is presented. Quaternion algebra has been used to calculate the ideal misorientation between product α variants for Kurdjumov–Sachs (KS) and its nearby orientation relationships, and arrive at the misorientation angle-axis set corresponding to packet (12 types), block (3 types) and sub-block boundaries. Analysis of proximity of experimental misorientation between data points from the theoretical misorientation set is found to be useful for identifying the different types of martensite boundaries. The optimal OR in the alloy system and the critical deviation threshold for identification of martensite boundaries could both be ascertained by invoking the ‘Enhancement Factor’ concept. The prior-γ grain boundaries, packet, block and sub-block boundaries could be identified reasonably well, and their average intercept lengths in a typical tempered martensite microstructure of 9Cr–1Mo–0.1C steel was estimated as 31 μm, 14 μm, 9 μm and 4 μm respectively. 相似文献
64.
Vladan Mlinar 《Annalen der Physik》2015,527(3-4):187-204
In the light of recent developments in computer technology, a promising and efficient way to design a material with a desired property would be to solve the inverse problem: use a physical property to predict structure. Here, we discuss the basic idea and mathematical foundation of the inverse approach, and proposed strategies for its utilization in the design of materials over nano‐ to macro‐scales. At the nano‐scale, analyzed strategies include scanning of a high‐dimensional space of chemical compounds for those compounds that have a targeted property, and identification of correlations in large databases of materials. However, unlike utilization of inverse approach at nano‐scale where full structural information ‐ atoms and their positions‐ is linked to targeted properties, at the meso‐ and macro‐scale, only partial structural information, manifested via structural motifs or representative volume elements, is available. We discuss the role of partial structural information in the inverse approach to the design of materials at those scales. Risks and limitations of the inverse approach are analyzed and dependence of the approach on factors such as structure parametrization, approximations in theoretical models, and feedback from structural characterization, is addressed.
65.
基于纳米尺寸下复合铁电材料和反铁磁性材料是一个探索多铁性材料有效的方法. 利用激光脉冲沉积制备出LaFeO3-YMnO3人工超晶格和掺入不同层LaFeO3, BiFeO3的Bi4Ti3O12的外延薄膜. 通过系统的X射线衍射、透射电子显微术、扫描透射电子显微术下的能量损失谱表征证明这些样品具有原子尺寸上清晰的界面和完整的层状结构. 磁性测试证明这些材料具有亚铁磁性. 特别是在0.5和1.5LaFeO3-Bi4Ti3O12中的亚铁磁性甚至能保持到室温. 就铁电性而言, 铁电性测试显示出LaFeO3-YMnO3和插入BiFeO3的Bi4Ti3O12样品中存在较大的漏电流, 而在0.5LaFeO3-Bi4Ti3O12样品中存在铁电性. 因此在0.5LaFeO3-Bi4Ti3O12中能够实现亚铁磁和铁电共存. 其次发现当掺入多层的钙钛矿(3层SrTiO3或2.5层LaFeO3)后, Bi4Ti3O12 的层状结构将出现结构失稳现象. 这些工作对于利用纳米复合开发新颖多铁性提供一些实例. 相似文献
66.
67.
Immacolata Faraone Fabiana Labanca Maria Ponticelli Nunziatina De Tommasi Luigi Milella 《Molecules (Basel, Switzerland)》2020,25(22)
The rapid spread of the new Coronavirus Disease 2019 (COVID-19) has actually become the newest challenge for the healthcare system since, to date, there is not an effective treatment. Among all drugs tested, Hydroxychloroquine (HCQ) has attracted significant attention. This systematic review aims to analyze preclinical and clinical studies on HCQ potential use in viral infection and chronic diseases. A systematic search of Scopus and PubMed databases was performed to identify clinical and preclinical studies on this argument; 2463 papers were identified and 133 studies were included. Regarding HCQ activity against COVID-19, it was noticed that despite the first data were promising, the latest outcomes highlighted the ineffectiveness of HCQ in the treatment of viral infection. Several trials have seen that HCQ administration did not improve severe illness and did not prevent the infection outbreak after virus exposure. By contrast, HCQ arises as a first-line treatment in managing autoimmune diseases such as rheumatoid arthritis, lupus erythematosus, and Sjögren syndrome. It also improves glucose and lipid homeostasis and reveals significant antibacterial activity. 相似文献
68.
69.
AbstractThe study on inhibitory effects of resveratrol glucosides (REs) on advanced glycation endproducts (AGEs) formation is still unmet. Herein, for the first time, the antiglycation activities of five REs in the fetal bovine serum proteins (FBS)/fructose system were evaluated, and its structure-activity relationship and antiglycation mechanism were further explored. These REs showed remarkable inhibition toward AGEs formation. Among them, Piceatannol-3'-O-glucoside (PG) exhibited highest antiglycation activity as reflected in approximately 80% inhibition of fluorescent AGEs at the concentration of 1.0?mM. The structure-activity relationship analysis indicated that glucoside attached to the B ring of resveratrol displays a superior antiglycation activity. Moreover, the results of antiglycation mechanism showed that the antiglycation activity of REs was proportional to their antioxidant capacity and methylglyoxal (MGO) trapping capacity. Therefore, the REs are promising candidates worthy of further exploration for preventing AGEs accumulation in vivo, thereby treating AGEs-associated diseases. 相似文献
70.
Dr. Andrea Marraffa Dr. Piero Presenti Prof. Beatrice Macchi Dr. Francesca Marino-Merlo Prof. Mariella Mella Prof. Paolo Quadrelli 《ChemistryOpen》2020,9(5):528-537
Two new families of N,O-nucleoside analogues containing the anthracene moiety introduced through the nitrosocarbonyl ene reaction with allylic alcohols were prepared. The core structure is an isoxazolidine heterocycle that introduces either atom either a phenyl ring or dimethyl moiety at the C3 carbon. Different heterobases were inserted at the position 5 of the heterocyclic ring. One of the synthesized compounds demonstrated a good capacity to induce cell death and an appreciable nuclear fragmentation was evidenced in treated cells. 相似文献