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排序方式: 共有297条查询结果,搜索用时 15 毫秒
251.
Franciele Queiroz Ames Lívia Bracht Francielle Sato Lidiane Vizioli de Castro-Hoshino Bruno Ambrósio da Rocha Letícia Aparecida de Oliveira 《Natural product research》2020,34(16):2341-2345
Abstract Fish oil (FO) is a natural source of omega-3 fatty acids, with well-established beneficial effects in inflammatory diseases when FO is orally administered. This study investigated the effects of a topically applied FO preparation (FOP) on phenol-induced ear edema and evaluated the percutaneous penetration of FOP in ear tissue. After applying phenol, groups of mice received FOP on the ear. After 1?h, ear tissue was collected to determine the percent inhibition of edema, myeloperoxidase activity, and to perform photoacoustic spectroscopy (PAS). Treatment with FOP did not reduce edema, but reduced myeloperoxidase activity. The FOP decreased the area of bands that characterize inflamed tissue and penetrated into the tissue. These results indicated an inhibitory effect of FOP on leukocyte recruitment in phenol-induced ear edema. These data support the applicability of PAS as a non-destructive method for evaluating the inflammatory response, percutaneous penetration and antiinflammatory activity of compounds. 相似文献
252.
Ferreira KQ Schneider JF Nascente PA Rodrigues-Filho UP Tfouni E 《Journal of colloid and interface science》2006,300(2):543-552
The immobilization and properties of the nitric oxide donor trans-[Ru(NO)Cl(cyclam)](PF(6))(2), RuNO, entrapped in a silica matrix by the sol-gel process is reported herein. The entrapped nitrosyl complex was characterized by spectroscopic (UV-vis, infrared (IR), X-ray photoelectron, and (13)C and (29)Si MAS NMR) and electrochemical techniques. The entrapped species exhibit one characteristic absorption band in the UV-vis region of the electronic spectrum at 354 nm and one IR nu(NO) stretching band at 1865 cm(-1), as does the RuNO species in aqueous solution. Our results show that trans-[Ru(NO)Cl(cyclam)](PF(6))(2) can be entrapped in a SiO(2) matrix with preservation of the molecular structure. However, in a SiO(2)/SiNH(2) matrix, the complex undergoes a nucleophilic attack by the amine group at the nitrosonium. Irradiation of the complex, entrapped in the SiO(2) matrix, with light of 334 nm, resulted in NO release. The material was regenerated to its initial nitrosyl form by reaction with nitric oxide. 相似文献
253.
The use of histidine-agarose chromatography in the purification of supercoiled (sc) plasmid DNA (pDNA) from Escherichia coli lysates has been reported recently. In the current work we describe a set of breakthrough experiments which were designed to study the effect of parameters such as flow-rate, temperature, concentration and conformation on the dynamic binding capacity of pDNA to the histidine support. One of the most striking results shows that the dynamic binding capacity for sc pDNA decreases linearly from 250.8 to 192.0 microg sc pDNA/mL when the temperature is varied from 5 to 24 degrees C. This behaviour was attributed to temperature-induced, pre-denaturation conformational changes which promote the removal of negative superhelical turns in sc pDNA molecules and decrease the interaction of DNA bases with the histidine ligands. The capacity for sc pDNA was highly improved when using feeds with higher pDNA concentrations, a phenomenon which was attributed to the fact that pDNA molecules in more concentrated solutions are significantly compressed. A maximum capacity of 530.0 microg pDNA/mL gel was obtained when using a 125 microg/mL pDNA feed at 1 mL/min and 5 degrees C, a figure which is comparable to the plasmid capacity values published for other chromatographic supports. Finally, a more than 2-fold increase in capacity was obtained when changing from open circular to sc pDNA solutions. Overall, the results obtained provide valuable information for the future development and implementation of histidine chromatography in the process scale purification of pDNA. 相似文献
254.
The inherent selectivity of the antibody was combined with in-tube solid-phase microextraction by immobilization of the antibody into the fused silica capillary. A sensitive, selective, and reproducible immunoaffinity in-tube solid-phase microextraction coupled with liquid chromatography-mass spectrometry (in-tube SPME/LC-MS) method was developed, and validated for fluoxetine analysis in human serum. Important factors in the optimization of in-tube SPME variables, as well as the evaluation of the immunoaffinity capillary capacity are discussed. The in-tube SPME/LC-MS method presented a limit of quantitation of 5.00 ng/mL, and precision intra-assays with RSDs lower than 5%. The response of the in-tube SPME/LC-MS method for fluoxetine was linear over a dynamic range from 5.00 to 50.00 ng/mL, with correlation coefficients better than 0.998. Based on analytical validation it was demonstrated that in-tube SPME/LC-MS method offers high sensitivity, selectivity, and enough reproducibility to permit the quantification of fluoxetine in human serum at therapeutic levels. Thus, the proposed SPME/LC method can be useful tool to determine fluoxetine serum concentrations in patients receiving therapeutic dosages. 相似文献
255.
Identification of fly eggs using scanning electron microscopy for forensic investigations 总被引:1,自引:0,他引:1
Mendonça PM dos Santos-Mallet JR de Mello RP Gomes L de Carvalho Queiroz MM 《Micron (Oxford, England : 1993)》2008,39(7):802-807
Forensic entomology is the science that studies the role of insects in decomposing corpses and one of the most common uses is to estimate the post-mortem interval (PMI) based on insect activity on a decomposing body. Usually, flies are the first insects to reach a carcass and are able to oviposit on carrion within a few hours after death. Scanning electron microscopy (SEM) gives detailed information about morphological characters helping to identify the immature forms of flies and consequently serves as a tool in crime scene investigations. Sometimes, only eggs and larvae are found in corpses. Some dipteral species are important because their larvae develop in organic matter. The aim of this study is to identify eggs of species of forensic importance, such as Chrysomya megacephala, Chrysomya putoria, Lucilia cuprina, Lucilia eximia and Ophyra aenescens, using scanning electron microscopy (SEM). C. megacephala had no anastomosis or holes at the top of the islands and C. putoria had few anastomoses and no holes, whereas L. eximia and O. aenescens were found to have anastomoses and holes and L. cuprina had only anastomoses. The median area was bifurcated anteriorly in C. megacephala, L. eximia and O. aenescens and rounded in C. putoria and L. cuprina. Also the sculptures observed in the chorionic cells, the length and the way that median area ends up posteriorly are characteristics of great diagnostic value to identify muscoids of forensic importance. 相似文献
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258.
L. R. Calixto D. M. Lima R. S. Queiroz A. N. S. Rastelli V. S. Bagnato M. F. Andrade 《Laser Physics》2008,18(11):1365-1369
The purpose of this study was to evaluate the polymerization effectiveness of a composite resin (Z-250) utilizing microhardness testing. In total, 80 samples with thicknesses of 2 and 4 mm were made, which were photoactivated by a conventional halogen light-curing unit, and light-curing units based on LED. The samples were stored in water distilled for 24 h at 37°C. The Vickers microhardness was performed by the MMT-3 microhardness tester. The microhardness means obtained were as follows: G1, 72.88; G2, 69.35; G3, 67.66; G4, 69.71; G5, 70.95; G6, 75.19; G7, 72.96; and G8, 71.62. The data were submitted to an analysis of variance (ANOVA’s test), adopting a significance level of 5%. The results showed that, in general, there were no statistical differences between the halogen and LED light-curing units used with the same parameters. 相似文献
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