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71.
An aqueous solution of sodium citrate stabilized gold nanoparticles (AuNP) in the presence of N-lauroyl-L-alanine (C12ALA) forms a stable gel. The structure of the gel and the distribution profile of AuNP in it were analyzed. Will nanoparticles separated from each other with sodium citrate behave in the same way in solution and trapped in the gel matrix? Will the spatial limitation of solvent molecules aggregate nanoparticles and destroy their homogeneity? These questions are very important from the point of view of the use of gold nanoparticles, trapped in the gel structure as carriers of drugs in the slow-release process. The lack of homogeneity of this distribution will have a major impact on the rate of release of the appropriate amount of therapeutic drug from the matrix. In this work, we attempt to answer these questions. The performed biological assays revealed that both C12ALA and C12ALA-AuNP show an excellent level of biological neutrality. They might be used as a transporting medium for a drug delivery without affecting the drug’s activity.  相似文献   
72.
Psoriasis is a common, chronic systemic inflammatory disease affecting 125 million people worldwide. It is associated with several important conditions, including psoriatic arthritis, cardiometabolic syndrome, and depression, leading to a significant reduction in patients’ quality of life. Current treatments only reduce symptoms, not cure. This review discusses the mechanisms involved in the initiation and development of the disease, the role of oxidative stress in this autoimmune disease, as well as potential therapeutic options with substances of natural origin. The main aim of the study is intended to offer a review of the literature to present plants and phytochemicals that can represent potential remedies in the fight against psoriasis. We identified many in vitro, in vivo, and clinical trials studies that evaluated the relationship between chosen natural substances and immune system response in the course of psoriasis. We sought to find articles about the efficacy of potential natural-derived drugs in controlling symptoms and their ability to maintain long-term disease inactivity without side effects, and the result of our work is a review, which highlights the effectiveness of plant-derived drugs in controlling the inflammatory burden on psoriatic patients by decreasing the oxidative stress conditions.  相似文献   
73.
The paper presents basic studies on the precipitation of platinum, palladium, rhodium, and ruthenium nanoparticles from model acidic solutions using sodium borohydride, ascorbic acid, and sodium formate as reducing agents and polyvinylpyrrolidone as a stabilizing agent. The size of the obtained PGM particles after precipitation with NaBH4 solution does not exceed 55 nm. NaBH4 is an efficient reducer; the precipitation yields for Pt, Pd, Ru, Rh are 75, 90, 65 and 85%, respectively. By precipitation with ascorbic acid, it is possible to efficiently separate Pt, Rh, and Ru from Pd from the two-component mixtures. The obtained Pt, Pd, and Rh precipitates have the catalytic ability of the catalytic reaction of p-nitrophenol to p-aminophenol. The morphological characteristic of the PGM precipitates was analyzed by AFM, SEM-EDS, and TEM.  相似文献   
74.
75.
The excited-state intramolecular proton transfer chromophores were regarded as good materials for laser action generation due to their inherent four-level photocycle. The excitation-dependent properties of these compounds enable light amplification from two distinct forms: both enol and keto, making it possible to obtain dual fluorescence emission. Herein, we report that a third option is possible for the first time stimulated emission was realized with a deprotonated ESIPT molecule based on a novel rigidified 2-(2’-hydroxyphenyl)benzothiazole derivative, triggering the possibility to fabricate real-time tunable active material. Through the rational engineering of the ratio of each emissive species, a red-green-blue device was fabricated with the possibility of white light generation. The degenerated two-wave mixing setup was applied to construct a continuously tunable distributed feedback laser.  相似文献   
76.
In this article, the ability of two‐component photoinitiator systems for efficient polymerization of 2‐ethyl‐2‐(hydroxymethyl)?1,3‐propanediol triacrylate was presented. The photophysics and photochemistry of squaraine dyes in the presence of an electron donor as well as an electron acceptor was investigated, and it was found that the photosensitizer in an excited state might act as an electron acceptor or an electron donor. The excited states of squaraines may be quenched by tetramethylammonium n‐butyltriphenylborate ( B2 ), diphenyliodonium chloride ( I1 ), and N‐methoxy‐4‐phenylpyridinium tetrafluoroborate ( NO ). © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55 , 471–484  相似文献   
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78.
As a regional product, Koryciński cheese is one of the most important cheeses in the Podlasie region of Poland. In this study, the influence of technological processes, such as ripening, on shaping the organoleptic characteristics of cheese was determined. Korycin-type cheeses are produced from cow’s milk according to traditional technology. The ripening process lasted 466 h at 5 °C, 10 °C, and 15 °C. The aging temperature had a decisive influence on the number of esters and organic acids formed, which were analyzed by gas chromatography–mass spectrometry (GC/MS). The organoleptic properties of the cheeses were also related to the ripening temperature.  相似文献   
79.
A silver Compact Disc Recortable (CD-R) based substrate has been proposed as an alternative to silver colloids as active material successfully used in surface-enhanced Raman spectroscopy (SERS). Scanning Electron Microscope (SEM) and Energy-Dispersive X-ray Spectroscopy (EDXS) measurements revealed that silver nanoparticles are present over the entire surface of the uncovered reflective layer of commonly used CD-R. The process of preparation of the CD-R based surface is simple, fast and repeatable. Recorded Raman spectra of 10 µM Rhodamine 6G applied to the substrate corroborate strong enhancement of Raman signal. The maximum value of EF was calculated to be about 5.76 × 106. Raman maps are consistent with SEM micrographs and confirmed the presence of a numerous SERS hot spots occurring on the trucks of CD-R based substrate.  相似文献   
80.
Abstract  (Z)-3-(3,4-diaryl-1,2,4-triazole-5-yl)prop-2-enoic acid derivatives were obtained in the course of the reaction of N 3-substituted amidrazones with maleic anhydride, and isomerized into the (E) isomers by heating under reflux in acetic acid solution. The molecular structure of the compounds obtained was confirmed by IR and 1H NMR spectroscopy, and by X-ray crystallography for (2E)-3-(4,5-diphenyl-4H-1,2,4-triazol-3-yl)prop-2-enoic acid. The antiviral and immunomodulating activity of several of the compounds was examined. Graphical abstract     相似文献   
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