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331.
Ana Paula Pires Eisele Débora Nóbile Clausen César Ricardo Teixeira Tarley Luiz Henrique Dall'Antonia Elen Romão Sartori 《Electroanalysis》2013,25(7):1734-1741
An electroanalytical method for the simultaneous determination of paracetamol (PAR), caffeine (CAF), and orphenadrine (ORPH) using the square‐wave voltammetry (SWV) and a cathodically pretreated boron‐doped diamond electrode was developed. The method exhibits linear responses to PAR, CAF, and ORPH in the concentration ranges 5.4×10?7–6.1×10?5 M, 7.8×10?7–3.5×10?5 M, and 7.8×10?7–3.5×10?5 M, respectively, with detection limits of 2.3×10?7 M, 9.6×10?8 M, and 8.4×10?8 M, respectively. The proposed method was successfully applied in the simultaneous determination of these analytes in pharmaceutical formulations. 相似文献
332.
Heats of adsorption of organic molecules are a useful tool for the characterization of porosity and surface chemistry of microporous
materials. This work describes the possibility of using heats of adsorption of organic molecules, estimated from a methodology
derived from the Dubinin-Astakhov equation, for the characterization of Pillared Interlayered Clays. The estimated heats were
compared with data determined directly by adsorption microcalorimetry. It is shown that the chemical nature of the organic
probe molecule strongly conditions the obtained results. The best agreement between calculated and experimental values, amongst
the probe molecules studied, was found for toluene. 相似文献
333.
334.
Rafaela Dias Oliveira Snia Pires Celeiro Catarina Barbosa-Matos Ana Sofia Freitas Susana M. Cardoso Marta Viana-Pereira Cristina Almeida-Aguiar Ftima Baltazar 《Molecules (Basel, Switzerland)》2022,27(11)
Melanoma is the most aggressive and life-threatening skin cancer type. The melanoma genome is the most frequently mutated, with the BRAF mutation present in 40–60% of melanoma cases. BRAF-mutated melanomas are characterized by a higher aggressiveness and progression. Adjuvant targeted treatments, such as BRAF and MEK inhibitors, are added to surgical excision in BRAF-mutated metastatic melanomas to maximize treatment effectiveness. However, resistance remains the major therapeutic problem. Interest in natural products, like propolis, for therapeutic applications, has increased in the last years. Propolis healing proprieties offer great potential for the development of novel cancer drugs. As the activity of Portuguese propolis has never been studied in melanoma, we evaluated the antitumoral activity of propolis from Gerês (G18.EE) and its fractions (n-hexane, ethyl acetate (EtOAc), and n-butanol) in A375 and WM9 melanoma cell lines. Results from DPPH•/ABTS• radical scavenging assays indicated that the samples had relevant antioxidant activity, however, this was not confirmed in the cell models. G18.EE and its fractions decreased cell viability (SRB assay) and promoted ROS production (DHE/Mitotracker probes by flow cytometry), leading to activation of apoptotic signaling (expression of apoptosis markers). Our results suggest that the n-BuOH fraction has the potential to be explored in the pharmacological therapy of melanoma. 相似文献
335.
Since 1961, aliphatic polyisocyanates based on HDI-biurets are used as light stable hardeners for 2-K polyurethane coatings. The market introduction of the HDI-isocyanurates or simply 'trimers' in the early 1980's was driven by their lower viscosity and their better monomer stability. The most recent development in HDI-polyisocyanate research are the iminooxadiazinediones (asymmetric trimers). In this paper, a new product based on that technology with a very low viscosity (700 mPas@23°C) and a NCO-functionality of more than 3 is presented. Because of its low viscosity, this hardener can be easily incorporated into aqueous systems and is the solution for high and full solids coatings as well. 相似文献