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81.
Paulo R. R. Costa ClÁUdio C. Lopes Rosacaronngela S. C. Lopes Maria F. G. Marinho Rosane N. Castro 《合成通讯》2013,43(14):1723-1730
Phthalides have bcen employed as useful intcriucdiates in tic sqrnthcsis of my condcnscld aromatic carbocyclic and heterocyclic compounds, including several natural products In this paper we report two alternative synthetic pathways for the preparation of phthalides as shown for the synthesis of the isomeric pairs of compounds 5a-d and 7a-d. 相似文献
82.
Nascimento Rebecca A. B. Medeiros Rodolfo L. B. A. Costa Tiago R. Oliveira Ângelo A. S. Macedo Heloísa P. Melo Marcus A. F. Melo Dulce M. A. 《Journal of Thermal Analysis and Calorimetry》2020,140(6):2673-2685
Journal of Thermal Analysis and Calorimetry - Mn-based solid oxygen carriers supported on MgAl2O4 were prepared by the microwave-assisted combustion method followed by wet impregnation of the... 相似文献
83.
César IC Bastos LF Godin AM Coelho Mde M Araujo DP de Fátima  Guidine PA Pianetti GA 《Journal of mass spectrometry : JMS》2011,46(11):1125-1130
A liquid chromatography-electrospray ionization tandem mass spectrometry method was developed and validated for the simultaneous quantitation of nicorandil and its denitrated metabolite, N-(2-hydroxyethyl)-nicotinamide, in rat plasma. After a liquid-liquid extraction step, chromatographic separation was performed on a ShinPack C(18) column with an isocratic mobile phase composed of methanol and 2 mM aqueous ammonium acetate containing 0.03% (v/v) formic acid (33:67 v/v). Procainamide was used as an internal standard (IS). Selected reaction monitoring was performed using the transitions m/z 212 → m/z 135, m/z 166 → m/z 106 and m/z 236 → m/z 163 to quantify nicorandil, its denitrated metabolite and IS, respectively. Calibration curves were constructed over the range of 5-15,000 ng.ml(-1) for both nicorandil and its metabolite. The mean relative standard deviation (RSD%) values for the intra-run precision were 5.4% and 7.3% and for the inter-run precision were 8.5% and 7.3% for nicorandil and its metabolite, respectively. The mean accuracy values were 100% and 95% for nicorandil and its metabolite, respectively. No matrix effect was detected in the samples. The validated method was successfully applied to a pharmacokinetic study after per os administration of nicorandil in rats. 相似文献
84.
Lago JH Souza ED Mariane B Pascon R Vallim MA Martins RC Baroli AA Carvalho BA Soares MG dos Santos RT Sartorelli P 《Molecules (Basel, Switzerland)》2011,16(12):9827-9837
The chemical composition and antimicrobial activity of essential oils obtained from leaves of two Myrtaceae species-Eugenia uniflora L. and Plinia trunciflora (O. Berg) Kausel-were determined. Analysis by GC/MS as well as determination of Kovatz indexes indicated atractylone (26.78%) and curzerene (17.96%) as major constituents of E. uniflora oil and α-cadinol (19.15%), apiole (11.15%) and cubenol (5.43%) as main components in P. trunciflora oil. Both essential oils were tested for antimicrobial activity against yeasts and bacteria. E. uniflora and P. trunciflora essential oils were active towards two Gram-positive bacteria, Streptococcus equi and Staphylococcus epidermis. In addition, biological activity of both essential oils was detected for pathogenic yeasts of the genus Candida and Cryptococcus. E. uniflora was active towards all yeast tested and exhibited interesting minimal inhibitory concentrations (0.11 to 3.75 mg/mL) across a broad spectrum of activity. 相似文献
85.
Batista FR Greco KN Astray RM Jorge SA Augusto EF Pereira CA Mendonça RZ Moraes AM 《Applied biochemistry and biotechnology》2011,163(1):1-13
An animal protein-free medium composed of IPL-41 containing 6 g L?1 yeastolate ultrafiltrate, 10 g L?1 glucose, 2 g L?1 lactose, 5 g L?1 glutamine, 1% lipid emulsion, and 0.1% Pluronic F-68 was used for producing recombinant proteins in batch mode employing two cell lines, S2AcRVGP2k expressing the G glycoprotein from rabies virus (RVGP) and S2AcHBsAgHy-9C expressing the surface antigen of hepatitis B virus (HBsAg), both obtained from Drosophila melanogaster S2 cells. Growth of wild-type S2 cells was also evaluated in the same medium. Cell behavior in the tested medium was compared to that verified in Sf900 II®. The results show that in shake flasks, S2AcRVGP2k and S2AcHBsAgHy-9C cells reached around 2?×?107 cells mL?1 in both media. In supplemented IPL-41 and Sf900 II® media, S2AcRVGP2k cells produced 367 ng RVGP mL?1 and 638 ng RVGP mL?1, respectively, while S2AcHBsAgHy-9C cells correspondently produced 573 ng HBsAg mL?1 and 322 ng HBsAg mL?1 in the mentioned media. In stirred tanks, S2AcRVGP2k cells reached 3?×?107 cells mL?1 and produced up to 758 ng RVGP mL?1. In general, glucose was consumed by cells, while lactate and ammonia were produced. 相似文献
86.
Rosângela Ferreira Frade de Araújo Tatiana Souza Porto Danyelly Bruneska Gondim Martins Rosa Fireman DutraAna Lúcia Figueiredo Porto José Luiz de Lima Filho 《Fluid Phase Equilibria》2011,301(1):46-50
Aqueous two-phase systems (ATPS) composed of polyethylene glycol (PEG)-citrate have been used for enzyme partitioning studies. The behavior of lactate dehydrogenase (LDH) from bovine heart crude extract was analyzed using a two-level factorial design in which the PEG molar mass and concentration, the citrate concentration were selected as independent variables, while the purification factor, the partition coefficient (K) and the activity yield were selected as responses. The statistical analysis revealed the effect of PEG molar mass on K. LDH exhibited a better partitioning toward PEG-rich phase and the highest K value (1079.81) was obtained with 42% (w/w) PEG 400 and 7.5% (w/w) citrate concentration. PEG molar mass also influenced the purification factor of the enzyme in the top phase. Possibly these ATPS remove inhibitors present in the extract affording higher enzyme yield. 相似文献
87.
Ángela Jiménez-Casas 《Journal of Mathematical Analysis and Applications》2011,379(2):567-588
We analyze the asymptotic behavior of the attractors of a parabolic problem when some reaction and potential terms are concentrated in a neighborhood of a portion Γ of the boundary and this neighborhood shrinks to Γ as a parameter ε goes to zero. We prove that the family of attractors is upper continuous at the ε=0. 相似文献
88.
89.
Cover Picture: Design and Sensing Properties of a Self‐Assembled Supramolecular Oligomer (Chem. Eur. J. 6/2016) 下载免费PDF全文
90.
Michaël Fanuel Carlos M. Alaíz Ángela Fernández Johan A.K. Suykens 《Applied and Computational Harmonic Analysis》2018,44(1):189-199
We propose a framework for the visualization of directed networks relying on the eigenfunctions of the magnetic Laplacian, called here Magnetic Eigenmaps. The magnetic Laplacian is a complex deformation of the well-known combinatorial Laplacian. Features such as density of links and directionality patterns are revealed by plotting the phases of the first magnetic eigenvectors. An interpretation of the magnetic eigenvectors is given in connection with the angular synchronization problem. Illustrations of our method are given for both artificial and real networks. 相似文献