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121.
122.
Tunde Jurca Liza Jzsa Ramona Suciu Annamaria Pallag Eleonora Marian Ildik Bcskay Mariana Murean Roxana Liana Stan Mariana Cevei Felicia Cioar Laura Vica Plma Fehr 《Molecules (Basel, Switzerland)》2021,26(1)
Topical anti-inflammatory and analgesic effect for the treatment of rheumatoid arthritis is of major interest because of their fewer side effects compared to oral therapy. The purpose of this study was to prepare different types of topical formulations (ointments and gels) containing synthetic and natural anti-inflammatory agents with different excipients (e.g.,: surfactants, gel-forming) for the treatment of rheumatoid arthritis. The combination of Non-Steroidal Anti-Inflammatory Drugs (NSAIDs), diclofenac sodium, a topical analgesic agent methyl salicylate, and a lyophilized extract of Calendula officinalis with antioxidant effect were used in our formulations. The aim was to select the appropriate excipients and dosage form for the formulation in order to enhance the diffusion of active substances and to certify the antioxidant, analgesic, and anti-inflammatory effects of these formulations. To characterize the physicochemical properties of the formulations, rheological studies, and texture profile analysis were carried out. Membrane diffusion and permeability studies were performed with Franz-diffusion method. The therapeutic properties of the formulations have been proven by an antioxidant assay and a randomized prospective study that was carried out on 115 patients with rheumatoid arthritis. The results showed that the treatment with the gel containing diclofenac sodium, methyl salicylate, and lyophilized Calendula officinalis as active ingredients, 2-propenoic acid homopolymer (Synthalen K) as gel-forming excipient, distilled water, triethanolamine, and glycerol had a beneficial analgesic and local anti-inflammatory effect. 相似文献
123.
B. B. Nanda R. R. Biswal R. Acharya J. S. B. Rao P. K. Pujari 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(3):1471-1474
Food and food products are the main sources of Aluminium entering the human body. In order to know aluminium contents in food and food products, selected 26 samples from local market were analyzed by instrumental neutron activation analysis (INAA) using reactor neutrons and high resolution gamma-ray spectrometry. INAA using 1,779 keV γ-ray of 28Al (2.24 min) was used for aluminium concentrations in the range of 33–529 mg kg?1. Two NIST standard reference materials (SRMs) and two IAEA reference materials (RMs) were analyzed by INAA for quantification of aluminium as a part of method validation. 相似文献
124.
Five Dimensional Bulk Viscous String Cosmological Models in Saez and Ballester Theory of Gravitation
G. C. Samanta S. K. Biswal P. K. Sahoo 《International Journal of Theoretical Physics》2013,52(5):1504-1514
LRS Bianchi type-I bulk viscous string cosmological models are obtained in scalar tensor theory of gravitation proposed by Saez and Ballester (Phys. Lett. A 113:467, 1986). It is shown that cosmic string does not survive for ρ+λ=0 whereas it survives for the equations of state ρ=(1+ω)λ (Takabayasi string) and ρ=λ (Geometric string). Some physical and geometrical properties of the exhibited model are discussed. 相似文献
125.
Echavarria Marino Everett Max Huang Shinyu Jacoby Liza Morrison Ralph Tewari Ayush K. Vlad Raluca Weber Ben 《Journal of Algebraic Combinatorics》2022,55(2):559-589
Journal of Algebraic Combinatorics - Given a lattice polygon P with g interior lattice points, we can associate to $$P$$ two moduli spaces: the moduli space of algebraic curves that are... 相似文献
126.
Liza B. Enrich Ashley Mohadjer Chrystal F. Eller Michael Fujinaka 《Tetrahedron letters》2008,49(16):2503-2505
An isolation procedure is presented that yields 2.4-3.7% w/w pure shikimic acid from the seeds of Liquidambar styraciflua (Sweetgum). Shikimic acid, the starting material in the commercial synthesis of the antiviral agent oseltamivir and an important intermediate in the biosynthesis of aromatic amino acids in plants, was found by HPLC to be abundant in the granular, aborted seeds (6.5% w/w) while present only in small amounts in the developed, fertile seeds (0.14% w/w). This extraction technique makes L. styraciflua, which is found in 40 states of the continental US, a potential renewable source of this important natural product. 相似文献
127.
Preparation, characterization, and photocatalytic activity of sulfate-modified titania for degradation of methyl orange under visible light 总被引:4,自引:0,他引:4
Parida KM Sahu N Biswal NR Naik B Pradhan AC 《Journal of colloid and interface science》2008,318(2):231-237
Hydrated titania was prepared by a sol-gel method, taking tetraisopropyl orthotitanate as starting material, and then promoted with different weight percentages of sulfate by an incipient wetness impregnation method. The materials were characterized by various advanced techniques such as PXRD, BET surface area, N(2) adsorption-desorption measurements, FTIR, and SEM. Analytical results demonstrated that TiO(2) is mesoporous in nature, and sulfate modification could inhibit the phase transformation and enhance the thermal stability of TiO(2). It was also found that sulfate modification could reduce the crystallite size and increase the specific surface area of the catalysts. The degradation of methyl orange under solar radiation was investigated to evaluate the photocatalytic activity of these materials. Effects of different parameters such as pH of the solution, amount of catalyst, additives, and kinetics were investigated. At 2.5 wt% sulfate loading, the average percentage of degradation of methyl orange was nearly two times than that of neat TiO(2). The photocatalytic degradation followed first-order kinetics. 相似文献
128.
Liza Mouret Grégory Da Costa Arnaud Bondon 《Magnetic resonance in chemistry : MRC》2014,52(7):339-344
Small unilamellar vesicles (SUVs) of phospholipids are often used as a membrane model system for studying the interaction of molecules. When using NMR under the standard liquid‐state conditions, SUV phospholipid proton spectra can be recorded, exhibiting sharp signals. This is not only because of the fast vesicular tumbling but also because of the combination of this tumbling with the individual motion of the lipids inside the bilayer. This appears evident because addition of cholesterol is responsible of broader resonances because of the slowing down of the lipid motion. On the other hand, no 1H signal is detected for cholesterol in the bilayer. This lack of detection of the inserted molecules explains why generally SUVs are not considered as a good model for NMR studies under the standard liquid‐state conditions. Here, we use two other sterols in order to demonstrate that an increase of the molecular mobility inside the bilayer could allow the detection of their proton resonances. For desmosterol and lanosterol, which show higher mobility inside the bilayer, with increasing lateral diffusion rates, 1H sterol signals are detected in contrast to cholesterol. For the fast diffusing lanosterol, no significant improvement in detection is observed using deuterated lipids, demonstrating that homonuclear dipolar coupling is fully averaged out. Furthermore, in the case of low mobility such as for cholesterol, the use of a fast magic angle spinning probe is shown to be efficient to recover the full proton spectrum. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
129.
A stochastic geometrical modeling technique is used to reconstruct a laboratory scale Fontainebleau sandstone with a sidelength of 1.5 cm. The model reconstruction is based on crystallite properties and diagenetic parameters determined from two-dimensional images. The three-dimensional pore scale microstructure of the sandstone is represented by a list of quartz crystallites defined geometrically and placed in the continuum. This allows generation of synthetic μ-CT images of the rock model at arbitrary resolutions. Quantitative microstructure comparison based on Minkowski functionals, two-point correlation function and local porosity theory indicates that this modeling technique can provide more realistic and accurate models of sandstones than many existing techniques used currently. Synthetic μ-CT images at different resolutions from a laboratory scale model of Fontainebleau sandstone are made available to the scientific community for resolution dependent petrophysical analysis. 相似文献
130.
ZnS nanoparticles were precipitated in aqueous dispersions of cationic surfactant cetyltrimethylammonium bromide (CTAB). The sphere radii of ZnS nanoparticles calculated by using band-gap energies steeply decreased from 4.5 nm to 2.2 nm within CTAB concentrations of 0.4-1.5 mmol L(-1). Above the concentration of 1.5 mmol L(-1), the radii were stabilized at R=2.0 nm and increased up to R=2.5 nm after 24 h. The hydrodynamic diameters of CTAB-ZnS structures observed by the dynamic light scattering (DLS) method ranged from 130 nm to 23 nm depending on CTAB concentrations of 0.5-1.5 mmol L(-1). The complex structures were observed by transmission electron microscopy (TEM). At the higher CTAB concentrations, ZnS nanoparticles were surrounded by CTA(+) bilayers forming positively charged micelles with the diameter of 10nm. The positive zeta-potentials of the micelles and their agglomerates were from 16 mV to 33 mV. Wurtzite and sphalerite nanoparticles with R=2.0 nm and 2.5 nm covered by CTA(+) were modeled with and without water. Calculated sublimation energies confirmed that a bilayer arrangement of CTA(+) on the ZnS nanoparticles was preferred to a monolayer. 相似文献