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Intraneural injection of 10-20 x 10(6) viable Mycobacterium leprae into the sciatic nerve of normal, unsensitized, Swiss white mice gives rise to a tuberculoid type of granulomatous response in 2 weeks. The same dose of viable M. leprae when injected into the sciatic nerves of unsensitized immunosuppressed mice (T200 x 5R) elicited a macrophage response. When macrophages were systemically immobilized using an intraperitoneal injection of silica quartz dust in normal mice, the lesion produced was of the lepromatous type, suggesting a role for the macrophage in the induction of the tuberculoid type of granulomatous response. In all of these in situ experiments, M. leprae failed to enter the Schwann cells.  相似文献   
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This work presents the influence of annealing on the structure and stoichiometry of europium (Eu)-doped titanium dioxide (TiO2). Thin films were fabricated by magnetron sputtering from a metallic Ti-Eu target in oxygen atmosphere and deposited on silicon and SiO2 substrates. After deposition the selected samples were additionally annealed in air up to 1070 K.Film properties were examined by means of X-ray diffraction (XRD), atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS) and the results were analyzed together with the undoped TiO2 thin films prepared under similar technological conditions.XRD results showed that depending on the Eu content, as-deposited thin films consisted of the TiO2-anatase or TiO2-rutile.An additional annealing will result in the growth of anatase crystals up to 35 nm, but anatase to rutile phase transformation has not been recorded. AFM images display high quality and a dense nanocrystalline structure. From the XPS Ti2p spectra the 4+oxidation state of Ti was confirmed. The O1s XPS spectra displayed the presence of an O2− photoelectron peak accompanied by an additional broader peak that originates from hydroxyl species chemisorbed at the sample surface. It has been found that Eu dopant increases the OH content on the surface of prepared TiO2:Eu thin films. The calculated O/Ti ratio was in the range of 1.85-2.04 depending on the sample.  相似文献   
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Syntheses of azafluorenones from monoazaphenanthrenes and phenanthrolines has ben investigated. 1- and 4-monoazaphenanthrenes have been oxidized by J2O5 in acetic acid to give quinones which were converted to 4- and 1-azafluoren-9-ones in alkaline media. Phenanthrolines can be oxidized directly by means of permanganate in alkaline medium to 1,5-, 1,6-, 1,8-, 2,5- and 3,5-diazafluoren-9-ones. From 1-, 4-azaphenanthrene- and 1,8-phenanthrolinequinones new benzopyrido- and dipyridophenazines have been synthesized.  相似文献   
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The food flavour additive octanoic acid (C8:0) is also a metabolite of the entomopathogenic fungus Conidiobolus coronatus, which efficiently infects and rapidly kills Galleria mellonella. GC-MS analysis confirmed the presence of C8:0 in insecticidal fraction FR3 extracted from C. coronatus filtrate. Topical administration of C8:0 had a dose-dependent effect on survival rates of larvae but not on pupation or adult eclosion times of the survivors. Topically applied C8:0 was more toxic to adults than larvae (LD100 for adults 18.33 ± 2.49 vs. 33.56 ± 2.57 µg/mg of body mass for larvae). The administration of C8:0 on the cuticle of larvae and adults, in amounts corresponding to their LD50 and LD100 doses, had a considerable impact on the two main defense systems engaged in protecting against pathogens, causing serious changes in the developmental-stage-specific profiles of free fatty acids (FFAs) covering the cuticle of larvae and adults and damaging larval hemocytes. In vitro cultures of G. mellonella hemocytes, either directly treated with C8:0 or taken from C8:0 treated larvae, revealed deformation of hemocytes, disordered networking, late apoptosis, and necrosis, as well as caspase 1–9 activation and elevation of 8-OHdG level. C8:0 was also confirmed to have a cytotoxic effect on the SF-9 insect cell line, as determined by WST-1 and LDH tests.  相似文献   
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This paper presents definitions and basic properties of uncertain variables and shows how they may be applied to the analysis and decision making in static systems with unknown parameters in their mathematical models. The unknown parameters are assumed to be uncertain variables described by certainty distributions given by an expert. Two versions of the uncertain variables are described. The uncertain variable in the first version may be considered as a special case of the fuzzy number with a specific interpretation. Two forms of systems are considered in the paper: a system described by a function (functional system) and a system described by a relation (relational system). In both cases the statements and general solutions of the analysis and decision problems are presented. Simple examples illustrating the application of the uncertain variables are included.  相似文献   
8.
Poly(acrylic acid) [poly(polypropenoic acid)] (PAA) can form stable and insoluble, colorless hydrogels with HfCl4, TiCl4, and ZrCl, in water. Two carboxylic groups of PAA are complexed by the M(OH)22+ ions. Hydrogels formed from PAA–MCl2,(OH)2, (where M = Hf, Zr) (2 : 1) have found practical application in the blocking of microscopic channels in tooth dentin, and thereby decrease the fluid permeability and protect against tooth decay. © 1996 John Wiley & Sons, Inc.  相似文献   
9.
In many pharmaceuticals, a hydrogen atom or hydroxyl group is replaced by a fluorine to increase bioavailability and biostability. The fate of fluorine released from fluorine-containing drugs is not well investigated. The aim of this study was to examine possible fluorination of proteins in rat liver and brain after administration of the fluorinated drug cinacalcet. We assigned 18 Wistar rats to a control group (n = 6) and a group treated with cinacalcet (2 mg kg−1/body weight, 5 days/week), divided into 7 day (n = 6) and 21 day (n = 6) treatment subgroups. Fluorinated proteins were identified using a free proteomics approach; chromatographic separation and analysis by high-resolution mass spectrometry; peptide/protein identification using the Mascot search algorithm; manual verification of an experimentally generated MS/MS spectrum with the theoretical MS/MS spectrum of identified fluorinated peptides. Three fluorinated proteins (spectrin beta chain; carbamoyl-phosphate synthase [ammonia], mitochondrial; 6-phosphofructo-2-kinase/fructose-2, 6-bisphosphatase 1) were identified in the liver and four (spectrin beta chain, dihydropyrimidinase-related protein 4, prominin-2, dihydropyrimidinase-related protein 4) in the brain tissue after 21 days of cinacalcet treatment, but not in the control group. Introduction of fluorine into an organism by administration of fluorinated drugs results in tissue-specific fluorination of proteins.  相似文献   
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