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排序方式: 共有532条查询结果,搜索用时 15 毫秒
81.
Marília Cavalcanti Coriolano Cristiane Moutinho Lagos de Melo Flávio de Oliveira Silva Giuliana Viegas Schirato Camila Souza Porto Paulo Jorge Parreira dos Santos Maria Tereza dos Santos Correia Ana Lúcia Figueiredo Porto Ana Maria dos Anjos Carneiro-Leão Luana Cassandra Breitenbach Barroso Coelho 《Applied biochemistry and biotechnology》2014,172(5):2682-2693
Parkia pendula seed lectin was used to treat cutaneous wounds of normal and immunocompromised mice, inducing cicatrization. Methotrexate (0.8 mg/kg/week) was used as immunosuppressive drug. Wounds were produced in the dorsal region (1 cm2) of female albino Swiss mice (Mus musculus), health and immunocompromised. Wounds were daily topically treated with 100 μL of the following solutions: (1) control (NaCl 0.15 M), (2) control Im (0.15 M NaCl), (3) P. pendula seed lectin (100 μg/mL), and (4) P. pendula seed lectin Im (100 μg/mL). Clinical evaluation was performed during 12 days. Biopsies for histopathology analysis and microbiological examinations were carried out in the second, seventh, and 12th days. The presence of edema and hyperemia was observed in all groups during inflammatory period. The first crust was detected from the second day, only in the groups treated with P. pendula seed lectin. Microbiological analysis of wounds from day 0 to day 2 did not show bacterium at P. pendula seed lectin group; however, Staphylococcus sp. was detected every day in the other groups. The lectin markedly induced a total wound closing at P. pendula seed lectin and P. pendula seed lectin Im groups on 11th day of evolution. The present study suggests that P. pendula seed lectin is a biomaterial potential to show pharmacological effect in the repair process of cutaneous wounds. 相似文献
82.
Cristiane dos Santos Luis Fernando Wentz Brum Robelsa de Fátima Vasconcelos Sérgio Knorr Velho João Henrique Zimnoch dos Santos 《Journal of Sol-Gel Science and Technology》2018,86(2):351-364
Natural dyes, namely, indigo carmine, cochineal carmine, curcumin and annatto, were encapsulated in silica by a sol-gel method and applied in the dyeing of different textile fibers by exhaustion. For comparative reasons, dyeing using the free (non-encapsulated) bare dyes was also carried out. The hybrid materials were analyzed by a set of techniques to investigate their elemental, structural, textural and morphological properties, and the results showed that it was possible to obtain stable natural dyes for applications in textile dyeing. The silica-structured dyes showed better affinities with the fibers (WO, PA, PAC and PET) in dyeing with cochineal carmine, while cotton (CO) showed better affinities with the encapsulated curcumin and annatto dyes. The performances of the encapsulated dyes were evaluated by color and washing fastness measurements and resulted in improved dye absorption and wash fastness properties. The color change and color transfer measurements of the encapsulated dyes were better (rated at 4–5 on a scale of 1–5) compared to the bare dyes. 相似文献
83.
Cristiane Antoniazzi Camila Alves de Lima Rafael Marangoni Almir Spinelli Eryza Guimarães de Castro 《Journal of Solid State Electrochemistry》2018,22(5):1373-1383
This paper reports the voltammetric determination of 17β-estradiol in urine and buttermilk samples using a simple detector based on a carbon paste electrode (CPE) modified with copper(II) oxide (CuO). The CuO was obtained by the Pechini method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive (EDS), Fourier transform infrared (FTIR), and Raman spectroscopies. Cyclic voltammetry (CV) and square-wave voltammetry (SWV) demonstrated that the CuO-modified carbon paste electrode (CuO/CPE detector) displayed much higher electrocatalytic activity in the 17β-estradiol oxidation reaction than the CPE without modification, exhibiting a low detection limit of 21.0 nmol L?1 with a wide linear range from 60.0 to 800.0 nmol L?1 (R = 0.998). Satisfactory results were obtained for the determination of 17β-estradiol in human urine and buttermilk samples. The proposed electrochemical detector offers high repeatability, stability, fast response, low cost, and potential for practical application in the quantification of this hormone. 相似文献
84.
Developing exact models of combustion instabilities is not an easy task to carry out and requires a great deal of time prior to obtaining success. The present study proposes a low-order model for pressure oscillations that does not require any knowledge of the systems, any new physical findings nor intricate details regarding its operating condition. This new approach is obtained using a Modified Van der Pol’s equation (MVDP) which is tuned by use of a Dual Extended Kalman Filter (DKEF) as a recursive estimator with perspectives in control by computer. This phenomenological model is used to predict the pressure signal from a variety of different combustors. Input data were taken from experimental cases such as a Rijke tube, a gas turbine and a liquid-fuel aero-engine combustor. Furthermore, a simulation considering high frequency oscillations to show the capability of the new approach is presented. In all cases, the results demonstrated the feasibility of applying the tractable model MVDP and DKEF running together to investigate pressure oscillations in practical cases. 相似文献
85.
Sequential Voltammetric Determination of Uranium,Cadmium and Lead by Using the ex situ Bismuth Film Electrode: Application to Phosphate Fertilizers 下载免费PDF全文
Cristiane L. Jost Lara M. di Martos Luis Ferraz Paulo Cícero do Nascimento 《Electroanalysis》2016,28(2):287-295
A sequential voltammetric procedure for the determination of uranium, cadmium and lead was investigated at an ex situ bismuth film electrode (BiFE). First, the adsorptive stripping voltammetry was applied to assay the U(VI)‐cupferron complex in the differential pulse mode (detection limit of 1.0 µg L?1, 200 s accumulation time). Through the manipulation of the same aliquot of the sample, efforts were made to quantify cadmium and lead by square wave anodic stripping voltammetry. Detection limits of 2.03 µg L?1 for Cd (II) and 2.43 µg L?1 for Pb (II) were calculated (100 s accumulation time). The methodology was successfully applied to phosphate fertilizer samples after open vessel wet decomposition (HNO3/H2O2). The following value ranges were evaluated: U (VI) 37.2–150 mg kg?1, Pb (II) 78.3–204 mg kg?1 and Cd (II) 44.1–71.6 mg kg?1. Validation was performed by using the standard reference materials SRM‐695 – phosphate fertilizer – and SRM‐1643e – water. 相似文献
86.
Carbon Paste Electrode Modified with Biochar for Sensitive Electrochemical Determination of Paraquat 下载免费PDF全文
Cristiane Kalinke Antonio S. Mangrich Luiz H. Marcolino‐Junior Márcio F. Bergamini 《Electroanalysis》2016,28(4):764-769
The present work reports for the first time the determination of paraquat (PQ2+) by Differential Pulse Adsorptive Stripping Voltammetry (DPAdSV) using a carbon paste electrode modified (CPME) with biochar obtained from castor oil cake at different temperatures (200–600 °C). The best voltammetric response was verified using biochar yielded at 400 °C (CPME‐BC400). Linear dynamic range (LDR) for PQ2+ concentrations between 3.0×10?8 and 1.0×10?6 mol L?1 and a limit of detection (LOD) of 7.5×10?9 mol L?1 were verified. The method was successfully applied for PQ2+ quantification in spiked samples of natural water and coconut water. 相似文献
87.
Natália Menezes Van Sérgio Alves Cristiane Morais Smith 《The European Physical Journal B - Condensed Matter and Complex Systems》2016,89(12):271
The experimental observation of the renormalization of the Fermi velocity v F as a function ofdoping has been a landmark for confirming the importance of electronic interactions ingraphene. Although the experiments were performed in the presence of a perpendicularmagnetic field B, the measurements are well described by arenormalization-group (RG) theory that did not include it. Here we clarify this issue, forboth massive and massless Dirac systems, and show that for the weak magnetic fields atwhich the experiments are performed, there is no change in the renormalization-groupfunctions. Our calculations are carried out in the framework of the Pseudo-quantumelectrodynamics (PQED) formalism, which accounts for dynamical interactions. We includeonly the linear dependence in B, and solve the problem using two differentparametrizations, the Feynman and the Schwinger one. We confirm the results obtainedearlier within the RG procedure and show that, within linear order in the magnetic field,the only contribution to the renormalization of the Fermi velocity for the massive casearises due to electronic interactions. In addition, for gapped systems, we observe arunning of the mass parameter. 相似文献
88.
Rümmeli MH Kramberger C Löffler M Jost O Bystrzejewski M Grüneis A Gemming T Pompe W Büchner B Pichler T 《The journal of physical chemistry. B》2007,111(28):8234-8241
In this Article, we describe a carbon nanotube formation model in which sp2 carbon hemispheres form the embryonic caps from which a nanotube can grow. This requirement leads to a single wall carbon nanotube formation window concomitant with our systematic experimental findings, which show upper and lower diameter limits. Further, the successful formation of a nucleation cap (hemisphere) is governed by catalyst particle volume to surface area considerations. Single wall carbon nanotubes are only obtained when both the nanotube formation window and the precipitating catalyst size distribution cross over. The extent to which these two windows overlap establishes the mean diameter and diameter distribution of the obtained single wall carbon nanotubes. 相似文献
89.
Cristiane Okuda Torello Marisa Claudia Alvarez Sara T. Olalla Saad 《Molecules (Basel, Switzerland)》2021,26(19)
Flavonoids are ubiquitous groups of polyphenolic compounds present in most natural products and plants. These substances have been shown to have promising chemopreventive and chemotherapeutic properties with multiple target interactions and multiple pathway regulations against various human cancers. Polyphenolic flavonoid compounds can block the initiation or reverse the promotion stage of multistep carcinogenesis. Quercetin is one of the most abundant flavonoids found in fruits and vegetables and has been shown to have multiple properties capable of reducing cell growth in cancer cells. Acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) therapy remains a challenge for hematologists worldwide, and the outcomes for patients with both disorders continue to be poor. This scenario indicates the increasing demand for innovative drugs and rational combinative therapies. Herein, we discuss the multitarget effects of the flavonoid quercetin, a naturally occurring flavonol, on AML and MDS. 相似文献
90.
We consider a Ginzburg-Landau type functional on S
2 with a 6
th
order potential and the corresponding selfduality equations. We study the limiting behavior in the two vortex case when
a coupling parameter tends to zero. This two vortex case is a limiting case for the Moser inequality, and we correspondingly
detect a rich and varied asymptotic behavior depending on the position of the vortices. We exploit analogies with the Nirenberg
problem for the prescribed Gauss curvature equation on S
2.
Received: December 3, 1997 相似文献