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71.
Cicero L. A. Freitas Francisca F. P. Santos Orlando M. Dantas-Junior Vital V. Inácio Edinardo F. F. Matias Lucindo J. Quintans-Júnior 《Natural product research》2020,34(16):2384-2388
Abstract The present study aimed to evaluate the antibacterial and modulatory activity of the Turnera subulate methyl extract in isolation or in combination with aminoglycoside antibiotics, using the microdilution method. The Turnera subulata methyl extract was used in isolation in the antibacterial assays and in combination with antibiotics in the modulation assays. All tests were performed in triplicates. The Turnera subulata methyl extract presented both antibacterial and antibiotic-modulatory effects in vitro, in isolation and in association with aminoglycosides. The extract activity depends on the bacterial strain and may be associated with the presence of tannins and flavonols. However, further studies are required to characterize the Turnera subulata potential for the development of new drugs against multiresistant bacteria. 相似文献
72.
Optimized spatial overlap in optical pump–X‐ray probe experiments with high repetition rate using laser‐induced surface distortions
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Matthias Reinhardt Azize Koc Wolfram Leitenberger Peter Gaal Matias Bargheer 《Journal of synchrotron radiation》2016,23(2):474-479
Ultrafast X‐ray diffraction experiments require careful adjustment of the spatial overlap between the optical excitation and the X‐ray probe pulse. This is especially challenging at high laser repetition rates. Sample distortions caused by the large heat load on the sample and the relatively low optical energy per pulse lead to only tiny signal changes. In consequence, this results in small footprints of the optical excitation on the sample, which turns the adjustment of the overlap difficult. Here a method for reliable overlap adjustment based on reciprocal space mapping of a laser excited thin film is presented. 相似文献
73.
Reggiani Vilela Gonçalves Rômulo Dias Novaes Mariáurea Matias Sarandy João Paulo Viana Leite Emerson Ferreira Vilela Marli do Carmo Cupertino 《Natural product research》2016,30(23):2738-2742
The aim of this study was to investigate the effect of leaves extract of Schizocalyx cuspidatus (A. St.-Hil.) Kainul. & B. Bremer on hepatic morphofunctional dysfunction induced by carbon tetrachloride (CCl4). Liver lesions were induced via intraperitoneal administration of CCl4 every 48 h for 12 days. Forty-nine rats were randomised into seven groups: G1: CCl4; G2: CCl4 (animals euthanised 24 h after last CCl4 application); G3: CCl4 + DMSO; G4: SCE 400 mg/kg; G5: DMSO (700 μl); G6: CCl4 + SCE 200 mg/kg and G7: CCl4 + SCE 400 mg/kg. SCE administration resulted in reduction in hydroperoxide levels, lipidic droplets and necrosis compared to G1, G2 and G3. There was an increase in the amount of collagen fibres in G1, G2 and G3 compared to the groups. These results show that the extract of SCE leaves has great potential for the recovery of liver damage after the application of CCl4. 相似文献
74.
Dr. Miryam Criado-Gonzalez Dr. Nuria Alegret Dr. Alejandro M. Fracaroli Dr. Daniele Mantione Dr. Gregorio Guzmán-González Dr. Rafael Del Olmo Dr. Kentaro Tashiro Dr. Liliana C. Tomé Dr. Matias L. Picchio Prof. David Mecerreyes 《Angewandte Chemie (International ed. in English)》2023,62(26):e202301489
Eutectogels are an emerging family of soft ionic materials alternative to ionic liquid gels and organogels, offering fresh perspectives for designing functional dynamic platforms in water-free environments. Herein, the first example of mixed ionic and electronic conducting supramolecular eutectogel composites is reported. A fluorescent glutamic acid-derived low-molecular-weight gelator (LMWG) was found to self-assemble into nanofibrillar networks in deep eutectic solvents (DES)/poly(3,4-ethylenedioxythiophene) (PEDOT): chondroitin sulfate dispersions. These dynamic materials displayed excellent injectability and self-healing properties, high ionic conductivity (up to 10−2 S cm−1), good biocompatibility, and fluorescence imaging ability. This set of features turns the mixed conducting supramolecular eutectogels into promising adaptive materials for bioimaging and electrostimulation applications. 相似文献
75.
It was proved [Opt. Lett. 30, 720 (2005)] that the deposition of an overlay of higher refractive index than that of the cladding on a long-period fiber grating (LPFG) causes large shifts in the attenuation bands induced by the grating. The result is an enhancement of the sensitivity of the LPFG to variations in the ambient and overlay refractive indices or the overlay thickness. The limitation of the previous design to materials with higher refractive indices than that of the cladding of the LPFG is overcome with a five-layer model. To this purpose, a first overlay of higher refractive index than that of the cladding of the LPFG will enhance the sensitivity of the device to variations in the refractive index of a second overlay of lower refractive index than that of the cladding of the LPFG. Moreover, it is proved that, if the second overlay is thick enough, its behavior resembles that of an infinite layer. 相似文献
76.
We consider a nonlocal aggregation equation with degenerate diffusion, which describes the mean-field limit of interacting particles driven by nonlocal interactions and localized repulsion. When the interaction potential is attractive, it is previously known that all steady states must be radially decreasing up to a translation, but uniqueness (for a given mass) within the radial class was open, except for some special interaction potentials. For general attractive potentials, we show that the uniqueness/nonuniqueness criteria are determined by the power of the degenerate diffusion, with the critical power being m = 2. In the case m ≥ 2, we show that for any attractive potential the steady state is unique for a fixed mass. In the case 1 < m < 2, we construct examples of smooth attractive potentials such that there are infinitely many radially decreasing steady states of the same mass. For the uniqueness proof, we develop a novel interpolation curve between two radially decreasing densities, and the key step is to show that the interaction energy is convex along this curve for any attractive interaction potential, which is of independent interest. © 2020 Wiley Periodicals LLC. 相似文献
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Adriano Costa de Camargo Anna Paula de Souza Silva Jackeline Cintra Soares Severino Matias de Alencar Cíntia Ladeira Handa Karina Silva Cordeiro Marcela Souza Figueira Geni R. Sampaio Elizabeth A. F. S. Torres Fereidoon Shahidi Andrs R. Schwember 《Molecules (Basel, Switzerland)》2021,26(2)
A clear gap with respect to the potential biological properties of wheat flavonoids exists in the available literature. This information is crucial for breeding programs aiming to produce new varieties presenting improved health benefits. Accordingly, advanced breeding lines of whole durum wheat were evaluated in this contribution. The highest recovery of phenolics was achieved using aqueous acetone (50:50, v/v), as verified by multi-response optimization, thus showing that phenolics could be largely underestimated by employing an inappropriate extraction. The concentration of derivatives of apigenin, the main phenolics present, ranged from 63.5 to 80.7%, as evaluated by LC–ESI-QTOF-MS. Phenolics from the breeding line 98 exhibited the highest ability in scavenging peroxyl radicals, reducing power as well as in terms of inhibition of pancreatic lipase activity, a key enzyme regulating the absorption of triacylglycerols. In contrast, none of the samples exhibited a significant anti-diabetic potential. Despite their high concentration compared to that of phenolic acids, results of this work do not support a significant antioxidant and pancreatic lipase inhibitory effect of durum wheat flavonoids. Therefore, breeding programs and animal and/or human trials related to the effect of durum wheat flavonoids on oxidative stress and absorption of triacylglycerols are discouraged at this point. 相似文献
80.
LANGLEY J. K. 《中国科学 数学(英文版)》2010,(3)
We determine all real meromorphic functions f in the plane such that f has finitely many zeros, the poles of f have bounded multiplicities, and f and F have finitely many non-real zeros, where F is a linear differential polynomial given by F = f (k) +Σk-1j=0ajf(j) , in which k≥2 and the coefficients aj are real numbers with a0≠0. 相似文献