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21.
Valeria Visalli Carolina Muscoli Iolanda Sacco Francesca Sculco Ernesto Palma Nicola Costa Carmela Colica Domenicantonio Rotiroti Vincenzo Mollace 《BMC neuroscience》2007,8(1):106
Background
HIV envelope gp 120 glycoprotein is released during active HIV infection of brain macrophages thereby generating inflammation and oxidative stress which contribute to the development of the AIDS-Dementia Complex (ADC). Gp120 has also been found capable to generate excitotoxic effect on brain tissue via enhancement of glutamatergic neurotransmission, leading to neuronal and astroglial damage, though the mechanism is still to be better understood. 相似文献22.
Electrochemical Sensor Based on Gold Nanoparticles Stabilized in Poly(Allylamine hydrochloride) for Determination of Vanillin 下载免费PDF全文
Tânia Regina Silva Daniela Brondani Eduardo Zapp Iolanda Cruz Vieira 《Electroanalysis》2015,27(2):465-472
Gold nanoparticles stabilized in poly(allylamine hydrochloride) (AuNP‐PAH) were synthesized, characterized and applied in the development of a new sensor for the determination of vanillin by square‐wave voltammetry. Under optimized conditions, the calibration curve showed a linear range for vanillin of 0.90 to 15.0 µmol L?1, with a limit of detection of 55 nmol L?1. The sensor demonstrated acceptable selectivity and stability, as well as good intra‐day and inter‐day repeatability and electrode‐to‐electrode repeatability (with relative standard deviations of 3.5, 4.5 and 3.9 %, respectively). The sensor was successfully applied in the determination of vanillin in different commercial samples. 相似文献
23.
Mazzucchelli I Rapetti M Fattore C Franco V Gatti G Perucca E 《Analytical and bioanalytical chemistry》2011,401(3):1013-1021
The development of a simple and rapid high-performance liquid chromatography (HPLC) method for the determination of the new
antiepileptic drug rufinamide (RFN) in human plasma and saliva is reported. Samples (250 μl) are alkalinized with ammonium
hydroxide (pH 9.25) and extracted with dichloromethane using metoclopramide as internal standard. Separation is achieved with
a Spherisorb silica column (250 × 4.6 mm i.d., 5 μm) at 30 °C using as mobile phase a solution of methanol/dichloromethane/n-hexane
10/25/65 (vol/vol/vol) mixed with 6 ml ammonium hydroxide. The instrument used was a Shimadzu LC-10Av chromatograph and flow
rate was 1.5 ml min-1, with a LaChrom L-7400 UV detector set at 230 nm. Calibration curves are linear [r
2 = 0.998 ± 0.002 for plasma (n = 10) and r
2 = 0.999 ± 0.001 for saliva (n = 9)] over the range of 0.25–20.0 μg ml-1, with a limit of quantification at 0.25 μg ml-1. Precision and accuracy are within current acceptability standards. The assay is suitable for pharmacokinetic studies in
humans and for therapeutic drug monitoring. 相似文献
24.
Eduardo Zapp Daniela Brondani Iolanda C. Vieira Jairton Dupont Carla W. Scheeren 《Electroanalysis》2011,23(3):764-776
A matrix comprising iridium nanoparticles and 1‐butyl‐3‐methylimidazolium tetrafluoroborate ionic liquid (Ir‐BMI.BF4) supported in montmorillonite (MMT) was obtained through an efficient incorporation process. This modified clay matrix (Ir‐BMI.BF4‐MMT) was used for the immobilization of the enzymes laccase (LAC) and polyphenol oxidase (PPO) and employed in the construction of a bi‐enzymatic biosensor for determination of rutin by square‐wave voltammetry. Under optimized conditions, the analytical curve showed a linear range for rutin concentrations from 9.17×10?8 to 3.10×10?6 mol L?1 with a detection limit of 3.09×10?8 mol L?1. The method was successfully applied to the determination of rutin content in pharmaceutical samples. 相似文献
25.
Francisco C. C. Arantes Antonio C. Moro Iolanda S. Klein Cristiana da Silva Adelino V. G. Netto Antonio E. Mauro Vânia M. Nogueira 《Journal of Thermal Analysis and Calorimetry》2011,106(2):379-383
The synthesis, spectroscopic characterization, and thermal analysis of the compounds [Pd(X)2(mtu)(PPh3)] (X = Cl− (1), SCN− (2); mtu = N-methylthiourea; PPh3 = triphenylphosphine) and [Pd(X)2(phtu)(PPh3)] (X = Cl− (3), SCN− (4); phtu = N-phenylthiourea) are described. The thermal decomposition of the compounds occurs in two, three, or four stages and the final
decomposition products were identified as Pd0 by X-ray powder diffraction. The thermal stability order of the complexes is 4 > 3>2 > 1. 相似文献
26.
Paola Franco Stefano Cardea Antonio Tabernero Iolanda De Marco 《Molecules (Basel, Switzerland)》2021,26(15)
Aerogels are open, three-dimensional, porous materials characterized by outstanding properties, such as low density, high porosity, and high surface area. They have been used in various fields as adsorbents, catalysts, materials for thermal insulation, or matrices for drug delivery. Aerogels have been successfully used for environmental applications to eliminate toxic and harmful substances—such as metal ions or organic dyes—contained in wastewater, and pollutants—including aromatic or oxygenated volatile organic compounds (VOCs)—contained in the air. This updated review on the use of different aerogels—for instance, graphene oxide-, cellulose-, chitosan-, and silica-based aerogels—provides information on their various applications in removing pollutants, the results obtained, and potential future developments. 相似文献
27.
Iolanda Porcar Clara M. Gmez Armando Codoer Vicente Soria Agustín Campos 《Macromolecular Symposia》1995,94(1):171-180
The interactions of poly (4-vinyl pyridine) with dimyristoylphosphatidic acid-based liposomes were studied in heterogeneous solution systems. The polymer was dispersed in aqueous buffer solutions of small unilamellar vesicles and after a suitable period of incubation to raise the equilibrium, the experiments has been conducted as a function of polymer concentration and temperature. According to the measurements of the steady-state fluorescence spectra, changes in the intensities as well as shifts in the emission peak wavelength, has served as raw data to accounting for the polymer-vesicle interactions. Quantitative evaluation of the interaction has been done using a simple associating model with some approximations. The key parameters evaluated were the amount of polymer bound and the number of charged lipids on a membrane site as well as the number of effective charges of poly (4-vinyl pyridine) chains at the liposome interface. 相似文献
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29.
Nomura CS Intima DP Oliveira PV Ruffini IA Krug FJ 《Analytical and bioanalytical chemistry》2008,391(4):1135-1137
An approach was developed for the preparation of cryogenic ground spiked filter papers with Cu and Zn for use as synthetic
calibrating standards for direct solid microanalysis. Solid sampling graphite furnace atomic absorption spectrometry was used
to evaluate the microhomogeneity and to check the applicability of the synthetic calibrating standards for the direct determination
of Cu and Zn in vegetable certified reference materials. The found concentrations presented no statistical differences at
the 95% confidence level. The homogeneity factors ranged from 2.7 to 4.2 for Cu and from 6.4 to 11.5 for Zn. 相似文献
30.
Lilian Cristina Trevizan Dário Santos Jr. Ricardo Elgul Samad Nilson Dias Vieira Jr. Cassiana Seimi Nomura Lidiane Cristina Nunes Iolanda Aparecida Rufini Francisco José Krug 《Spectrochimica Acta Part B: Atomic Spectroscopy》2008
Laser induced breakdown spectroscopy (LIBS) has become an analytical tool for the direct analysis of a large variety of materials in order to provide qualitative and/or quantitative information. However, there is a lack of information for LIBS analysis of agricultural and environmental samples. In this work a LIBS system has been evaluated for the determination of macronutrients (P, K, Ca, Mg) in pellets of vegetal reference materials. An experimental setup was designed by using a Nd:YAG laser operating at 1064 nm and an Echelle spectrometer with ICCD detector. The plasma temperature was estimated by Boltzmann plots and instrumental parameters such as delay time, lens-to-sample distance and pulse energy were evaluated. Certified reference materials as well as reference materials were used for analytical calibrations of P, K, Ca, and Mg. Most results of the direct analysis of plant samples by LIBS were in reasonable agreement with those obtained by ICP OES after wet acid decomposition. 相似文献