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961.
We have established a luminol- and a lucigenin-dependent CL methods to investigate the role of the receptors for Fc portion of IgG (FcgammaR) and/or complement receptors (CR) in mediating the oxidative burst in neutrophils from systemic lupus erythematosus (SLE) patients compared with healthy controls. In the luminol-CL system, all the reactive oxygen species (ROS) are responsible for light production, whereas in the lucigenin-CL system, only the first ROS generated, converts the lucigenin into an unstable intermediate molecule, which also emits light. First, neutrophils from healthy controls and SLE patients were stimulated with different IC opsonized or not with complement from normal human serum (NHS) or SLE serum, in presence of 10(-4) M luminol. This method was able to differentiate the role of the FcgammaR, CR and FcgammaR/CR co-operation in mediating the oxidative burst, as well as show that the oxidative burst mediated by these receptors was reduced in neutrophils from SLE patients. Second, neutrophils from healthy controls and SLE patients were stimulated with different IC, opsonized or not with NHS, in presence of 10(-3) M lucigenin. In this case, the lucigenin-CL system was also able to differentiate the role of FcgammaR and FcgammaR/CR co-operation, as well as show differences among healthy controls and two different groups of SLE patients according to their clinical manifestations. In conclusion, we have established two sensitive CL systems to study the role of FcgammaR and/or CR in stimulating the oxidative burst of neutrophils, which can be applied in monitoring the involvement of these receptors in the immunopathogenesis of SLE. 相似文献
962.
V. V. Lapachev O. A. Zagulyaeva V. P. Mamaev 《Chemistry of Heterocyclic Compounds》1975,11(8):991-994
The corresponding 2-pyrimidoylacetate esters (I, II) and 2-pyrimidoyl-acetonitrile (V) were obtained by condensation of pyrimidine-2-carboxylic acid esters with methyl acetate or acetonitrile. The structures of the tautomeric forms were determined by IR and PMR spectroscopy. The effect of a solvent and protonation of the pyrimidine ring on the ketone-enol equilibrium was examined. 相似文献
963.
Quantitative DTA results are presented for the phase changes in some cadmium and zinc n-alkanoates. Cadmium carboxylates form liquid crystal phases. The total entropy of the solid-to-liquid transition is small indicating a high degree of aggregation in the isotropic liquid. The phases previously reported by Skoulios are shown to be due to the presence of basic carboxylates. The zinc carboxylates have solid—solid transformations but do not form liquid crystal phases. The entropies of fusion are of the same order as those in the lead salts showing only a small degree of aggregation in the liquid. 相似文献
964.
Zusammenfassung In unpolaren Lösungsmitteln kondensieren sich monomeres und dimeres Malonitril mit Dimethylamino-phenyl-propenon zu linearen Dienen bzw. Trienen. 2-Cyan-5-dimethylamino-3-phenyl-2,4-pentadienamid (4) kann als Zwischenprodukt für die Bildung von Pyridonen aus Enaminoketonen und Cyanacetamid aufgefaßt werden, da in saurem Medium die Cyclisierung zum 2-Oxo-4-phenyl-1,2-dihydro-pyridin-3-carbonitril bzw. dem Carbonsäureamid gelingt.
Herrn Prof.O. Hromatka zum 65. Geburtstag gewidmet. 相似文献
Syntheses with nitriles, XXIX: The linear condensation products from dimethylaminophenyl propenone with malononitrile
Monomeric and dimeric malononitrile condense in nonpolar solvents with dimethylamino phenyl propenone to form linear dienes and trienes, resp. 2-Cyano-5-dimethylamino-3-phenyl-2,4-pentadienamide (4) represents an intermediate in the formation of pyridones from enamine ketones and cyanoacetamide. It is cyclised in acidic medium to 2-oxo-4-phenyl-1,2-dihydropyridine-3-carbonitrile (8) (or-3-carboxamide,9).
Herrn Prof.O. Hromatka zum 65. Geburtstag gewidmet. 相似文献
965.
O. A. Zagulyaeva I. V. Semushkina V. P. Mamaev 《Chemistry of Heterocyclic Compounds》1986,22(7):774-779
Some dihydropyrimidines have been obtained which contain a cyanoacetic ester or malononitrile residue and chlorine in positions, 2, 4, and 6. The reactions of these compounds with nucleophiles has been examined.For communication 2, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 963–969, July, 1986. 相似文献
966.
Kozhevnikov I. S. Kovalev V. L. Rusinov O. N. Chupakhin 《Chemistry of Heterocyclic Compounds》2001,37(9):1136-1140
3-R-6-Phenyl-1,2,4-triazine 4-oxides react with cyclic -diketones (dimethylbarbituric acid, dimedone, and indan) in both acidic (substrate activation) and basic conditions (nucleophile activation) with formation of H-adducts, intermediates in the nucleophilic substitution of hydrogen (SN
H) in 3-R-5-Nu-4-hydroxy-6-phenyl-4,5-dihydro-1,2,4-triazines. Oxidative aromatisation of these intermediates or auto-aromatisation of acylated (benzoyl chloride) at the NOH -adducts with elimination of benzoic acid gave the corresponding substituted 1,2,4-triazine 4-oxides or 1,2,4-triazines. 相似文献
967.
A quantitative compressed pellet infrared method used together with a micro-distillation to effect separation of the isomer has been developed and reported here for the analysis of ortho-, meta-, and para-terphonyl. The terphenyl content is determined on fractions isolated by distillation from radiation damaged samples. The compressed pellet infrared method is preferred instead of the more conventional solution technique since smaller quantities of isolated terphcnyl are required. The pellet method is applicable also to polyphenyls higher than the terphenyls. The solution technique is not due to the insolubility of the polyphenyls. It is expected that the compressed pellet spectral method developed here might well find application in the analysis of compounds other than polyphenyls. Results presented here appear to be the, first quantitative infrared data reported in the literaturu on polyphenyl compounds. 相似文献
968.
T. Ya. Safonova N. S. Gulyukina Yu. V. Novakovskaya E. A. Astaf'ev G. N. Bondarenko O. A. Petrii G. A. Tsirlina I. P. Beletskaya 《Russian Journal of Electrochemistry》2002,38(5):457-466
The conditions for electrochemical hydrogenation and anodic oxidation of -phenylvinylphosphonic acid and its 4-chloro- and 4-methyl-substituted derivatives on palladized platinum electrodes in aqueous sulfuric-acid solutions are found. It is shown that, in the system under study, the products of strong chemisorption are not the intermediates of the electrocatalytic hydrogenation. The reactant molecules are modeled by quantum-chemical methods in terms of the restricted Hartree–Fock approximation. The calculated charge distributions in reactant molecules are used for estimating the electrostatic components of works of approach and the orientation distributions in the reaction layer. 相似文献
969.
Chris Mussell Céline S. J. Wolff Briche Chris Hopley Gavin O’Connor 《Accreditation and quality assurance》2007,12(9):469-474
The method used at LGC for analysis of “total” 19-norandrosterone (19-norandrosterone glucuronide plus “free” 19-norandrosterone)
in urine for the Comité Consultatif pour la Quantité de Matière Pilot Study (CCQM-P68) is described. The analytical method
used was a modified version of the method developed at the National Measurement Institute of Australia, which used a hydrolysis
and derivatisation procedure first described by the German Sports University. This method is routinely used by World Anti-Doping
Agency-accredited laboratories for sports drug testing. The main modifications made to the method were the use of 19-norandrosterone
glucuronide as a calibration standard and 19-norandrosterone glucuronide-d4 as an isotopically labelled internal standard,
and the use of a bench-top quadrupole gas chromatograph–mass spectrometer. The results produced by LGC (2.14 ± 0.15 ng g−1 expanded uncertainty, coverage factor k = 2) were in excellent agreement with those from other participating national metrology institutes and thus further validates
the exact-matching isotope-dilution mass spectrometric procedures used at LGC for a wide range of reference measurement applications,
including measurement of ng g−1 levels of steroids in a biological matrix. 相似文献
970.
The possible routes of deactivation of electronically excited states of 4-methyl-7-hydroxy-2-quinolone and its protolytic forms were analyzed. The relative contribution of radiative and nonradiative deactivation channels of electronic excitation energy was determined, and the rate constants of photophysical processes (internal conversion and intersystem crossing) occurring upon light absorption by these forms were estimated. 相似文献