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981.
Markus Wörnle Matthias Sauter Kathrin Kastenmüller Andrea Ribeiro Thomas Mussack Roland Ladurner Thomas Sitter 《Applied biochemistry and biotechnology》2010,160(4):1179-1187
Interleukin-8 (IL-8) is a chemokine that has been shown to be a potent chemoattractant for polymorphonuclear neutrophils from
the vascular compartment into the pleural space during infectious pleural effusions. Mesothelial cells express the viral receptors
Toll-like receptor 3 (TLR3), RIG-I, and MDA5. Activation of these receptors by viral RNA exemplified by poly (I:C) RNA leads
to a time- and dose-dependent increase of mesothelial IL-8 synthesis. To show the specific effect of viral receptors, knockdown
experiments with short interfering RNA specific for TLR3, RIG-I and MDA5 were performed. This novel finding of functional
expression of these viral sensors on human mesothelial cells may indicate a novel link between viral infections and mesothelial
inflammation and indicates a pathophysiologic role of viral receptors in these processes. 相似文献
982.
983.
984.
Ana C. F. Ribeiro Victor M. M. Lobo Eduarda F. G. Azevedo 《Journal of solution chemistry》2001,30(12):1111-1115
Differential diffusion coefficients of ammonium monovanadate in water at 25°C and at concentrations from 0.001 to 0.05 mol-dm–3, have been measured using a conductimetric cell and an automatic apparatus to follow diffusion. The cell uses an open-ended capillary method and a conductimetric technique is used to follow the diffusion process by measuring the resistance of solutions inside the capillaries at recorded times. 相似文献
985.
G.A.M. Sfar H.B. Ribeiro L.M. Malard F.O. Plentz C. Fantini A.P. Santos G. de Freitas-Silva Y.M. Idemori 《Chemical physics letters》2008,462(1-3):109-111
Porphyrin-doped carbon nanotubes in sodium dodecylbenzenesulfonate (NaDDBS) aqueous solution were obtained from NaDDBS/carbon nanotube aqueous dispersions. Several phonon-assisted absorption and recombination processes seem to occur, including one-phonon and two-phonon processes, and remain present even upon porphyrin doping. Power-law scaling of exciton binding energies and environmental dielectric screening effects are used to infer the doping from photoluminescence maps. The dielectric constant of the 5,10,15,20-tetrakis(4-trimethylammonium phenyl) porphyrin (H2TTMAPP) in NaDDBS aqueous solution seems to be higher than the one of NaDDBS/aqueous solution apparently because the counterions have opposite net charges. 相似文献
986.
Given the solution (Xt ) of a Stochastic Differential System, two situat,ions are considered: computat,ion of Ef(Xt ) by a Monte–Carlo method and, in the ergodic case, integration of a function f w.r.t. the invariant probability law of (Xt ) by simulating a simple t,rajectory. For each case it is proved the expansion of the global approximat,ion error—for a class of discret,isat,ion schemes and of funct,ions f—in powers of the discretisation step size, extending in the fist case a result of Gragg for deterministic O.D.E. Some nn~nerical examples are shown to illust,rate the applicat,ion of extrapolation methods, justified by the foregoing expansion, in order to improve the approximation accuracy 相似文献
987.
Bassanetti I Mezzadri F Comotti A Sozzani P Gennari M Calestani G Marchiò L 《Journal of the American Chemical Society》2012,134(22):9142-9145
The complexation of a preorganized thioether-functionalized bis(pyrazolyl)methane ligand (L) with silver precursors produces supramolecular structures organized at two hierarchical levels: [AgL](6)(X)(6) metal-organic cyclic hexamers and their organization in 3D architectures. The cyclic toroidal hexamers of 22-26 ? external diameter are found to be stable already in solution before self-assembly into the crystalline state. In the 3D lattice, the hexameric building block are arranged in different highly symmetric space groups as a function of a variety of anions (cubic Fd3 with PF(6)(-) or BF(4)(-) and rhombohedral R3 with CF(3)SO(3)(-) or NO(3)(-)) and form cavities with the geometrical shapes of Platonic solids (tetrahedron and octahedron) that can be occupied by a variety of solvent molecules. Upon evacuation, cubic crystals can produce stable frameworks with permanent porosity, which can absorb reversibly several vapors, CO(2) and CH(4). 相似文献
988.
Nowadays, the use of a drug to modify a person's behavior with criminal intentions has become a growing public concern. In fact, stealthy drink spiking with certain drugs can cause the incapacitation of a potential victim of assault and in extreme cases can even lead to death. Belonging to the group of drugs used to commit drug-facilitated crimes is glibenclamide, which not only exhibits high sedation secondary effects but when subject to an overdose intake can lead to intense hypoglycemic episodes that could end with death. Suicide attempts and homicides through overdose with glibenclamide have already been reported. 相似文献
989.
Fernando Antonio Simas Vaz Arthur Damásio Moutinho Jose Paulo Rodrigues Furtado de Mendonça Ricardo Tavares de Araújo Sidney José Lima Ribeiro Ferminio César Polachini Younes Messaddeq Marcone Augusto Leal de Oliveira 《Microchemical Journal》2012
The preparation of photo-polymerized sol–gel monolithic stationary phases (MSP) within 100 μm internal diameter polyacrylate-coated fused-silica capillaries for use in capillary electrochromatography (CEC) was optimized. Eight mixtures containing different amounts of methacryloxypropyltrimethoxysilane (MPTMS) as the polymeric precursor, hydrochloric acid solution as the catalyst, toluene as the porogen and bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide (Irgacure 819) as the photo-initiator were irradiated at 370 nm inside the capillaries in order to complete the MSP polymerization, according to a fractional factorial experimental design 2IV4-1. All the preparation procedure, from capillary pretreatment until the MSP is ready to use in CEC, were made in less than four hours in mild conditions. A high pressurization injection device (HPID) useful for micro-volume syringes was built in order to achieve practical, controlled and precise injections of sols, solvents and electrolytes in the capillaries. The eight MSP were equally washed, conditioned and submitted to CEC procedures via short-end injection, which showed higher efficiency and peak height taking shorter analysis time. Electrochromatographic behaviors of the MSP were corroborated with morphological characterizations by scanning electron microscopy. The optimum condition, which allowed the separation of standard mixture containing thiourea (marker compound), naphthalene, acenaphthene, fluorene, phenanthrene and anthracene in twelve minutes without external pressure assistance, showed efficiencies up to 51,460 N/m, relative standard deviation from 0.05 to 3.3% for migration/retention time and from 0.14 to 1.6% for relative area (considering thiourea as an internal standard) and also showed no statistical evidence that three MSP prepared at the same condition are different within 95% confidence interval. 相似文献
990.
Hashimoto MC Prates RA Kato IT Núñez SC Courrol LC Ribeiro MS 《Photochemistry and photobiology》2012,88(3):590-595
Pseudomonas aeruginosa is considered one of the most important pathogens that represent life‐threatening risk in nosocomial environments, mainly in patients with severe burns. Antimicrobial photodynamic therapy (aPDT) has been effective to kill bacteria. The purpose of this study was to develop a burn wound and bloodstream infection model and verify aPDT effects on it. In vitro, we tested two wavelengths (blue and red LEDs) on a clinical isolate of P. aeruginosa strain with resistance to multiple antibiotics using HB:La+3 as photosensitizer. Verapamil® associated to aPDT was also studied. In vivo, P. aeruginosa‐infected burned mice were submitted to aPDT. Bacterial counting was performed on local infection and bloodstream. Survival time of animals was also monitored. In this study, aPDT was effective to reduce P. aeruginosa in vitro. In addition, Verapamil® assay showed that HB:La+3 is not recognized by ATP‐binding cassete (ABC) efflux pump mechanism. In the in vivo study, aPDT was able to reduce bacterial load in burn wounds, delay bacteremia and keep the bacterial levels in blood 2–3 logs lower compared with an untreated group. Mice survival was increased on 24 h. Thus, this result suggests that aPDT may also be a novel prophylactic treatment in the care of burned patients. 相似文献