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11.
F Quartulli E Pinelli A Broué-Chabbert S Gossart V Girard B Pipy 《Canadian Metallurgical Quarterly》1998,348(2-3):297-304
Using the human lung epithelial WI26VA4 cell line, we investigated the capacity of fenspiride, an anti-inflammatory drug with anti-bronchoconstrictor properties, to interfere with histamine-induced intracellular Ca2+ increase and eicosanoid formation. Histamine and a histamine H1 receptor agonist elicited a rapid and transient intracellular Ca2+ increase (0-60 s) in fluo 3-loaded WI26VA4 cells. This response was antagonized by the histamine H1 receptor antagonist, diphenhydramine, the histamine H2 receptor antagonist, cimetidine, having no effect. Fenspiride (10(-7)-10(-5) M) inhibited the histamine H1 receptor-induced Ca2+ increase. In addition, histamine induced a biphasic increase in arachidonic acid release. The initial rise (0-30 s), a rapid and transient arachidonic acid release, was responsible for the histamine-induced intracellular Ca2+ increase. In the second phase release (15-60 min), a sustained arachidonic acid release appeared to be associated with the formation of cyclooxygenase and lipoxygenase metabolites. Fenspiride (10(-5) M) abolished both phases of histamine-induced arachidonic acid release. These results suggest that anti-inflammatory and antibronchoconstrictor properties of fenspiride may result from the inhibition of these effects of histamine. 相似文献
12.
以新巨龙公司2301N综放工作面过断层为工程背景,通过微震监测、数值模拟和理论分析等方法,对深井特厚煤层断层活化规律进行研究。得到的主要结论为:(1) 根据2301N工作面微震监测结果,将断层活化分为应力显现阶段(距断层274.8~214 m)、蓄能阶段(距断层214~84 m)和结构活化阶段(距断层84~0 m),并采用数值模拟进行了验证;(2) 工作面过断层期间存在断层活化型冲击和断层煤柱型冲击2类动力灾害,断层活化型冲击的机制主要是开采诱发断层两侧煤岩体积聚的构造应力释放,断层煤柱型冲击地压机制主要是工作面开采引起断层煤柱应力的高度集中;(3) 根据工作面过断层期间冲击地压发生机制,提出相应的防治技术,并进行现场验证,保障了工作面的安全开采。研究结果对类似条件下的工作面安全开采具有一定的借鉴意义。 相似文献
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Aristide G. Douagui Innocent K. Kouame Kouadio Koffi Albert Tié Bi Goula Brou Dibi Droh Lanciné Gone Kapo Coulibaly Arsène M. Seka Auguste K. Kouassi Jules M. Oi Mangoua Issiaka Savane 《Journal of Hydro》2012,6(3):227-238
In this study, total coliforms, thermotolerant coliforms, Escherichia coli and groundwater nitrate concentration were monitored at 127 groundwater sampling points (only 62 water points for bacteriological parameters) located in the southern part of Abidjan District. Each water sampling location was sampled in March and July 2007, representing respectively the long dry season and the long wet season. Geostatistical methods were used to analyze the spatial variability of nitrates and the groundwater nitrate pollution risk. The maximum seasonal content of total coliforms and thermotolerant coliforms ranged from 400 to 1000 CFU/100 mL and from 200 to 500 CFU/100 mL respectively. Moreover, 94% of these locations presented traces of bacteriological contamination. This contamination was mainly recorded during the rainy period. The degree of correlation between bacterial abundance and chemical parameters is variable. Nitrites, ammonium and potassium favoured coliform abundance. In the 127 water points, groundwater nitrate concentrations ranged from 4 to 198 mg L?1 and were log-normally distributed in the study area. The groundwater contamination risk map indicated that the strongly urbanized west side of the site presented a high probability of exceeding the WHO drinking water standard (50 mg L?1NO3?). 相似文献
15.
Two-Dimensional Numerical Simulation of the Hydro-Sedimentary Phenomena in Lake Taabo, Côte d’Ivoire
Kouakou Lazare Kouassı Kouassi Innocent Kouame Kouakou Séraphin Konan Martin Sanchez Angulo Moussa Deme N’Diaye Hermann Edwige Meledje 《Water Resources Management》2013,27(12):4379-4394
In Côte d’Ivoire, most of the reservoirs built to improve water supply, electricity, agriculture and cattle no longer work because of silt deposits and euthrophication. This study aims at modeling the hydro-sedimentary functioning of Lake Taabo in order to understand the sedimentation phenomena taking place. In this survey, 204 water samples and 31 bottom sediment samples were taken, during different hydrological seasons, to estimate suspended sediment concentrations and characterize the bottom sediments of Lake Taabo. The study showed that suspended solid variations are related to hydrological seasons. During dry seasons, the lake is lightly loaded; the average concentration is 7.89 mg/L. At the other end of the scale, during rainy seasons, suspended sediment concentrations increase and the average concentration is around 16.30 mg/L. The bottom of the reservoir mostly consists of mud. Sands are found near the islands and the dam. Sand size varies from medium grain to coarse. The average grain size is 451.48 μm. The hydro-sedimentary environment of Lake Taabo was simulated by a transport model, coupled with a hydrodynamic model. The various simulation scenarios indicated that Lake Taabo is subject to 20 to 60 mm of annual deposits. The greater thicknesses were observed near the spillway and the power intake. 相似文献
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Capucine Jourdain de Muizon Sridévi M. Ramanoudjame Lucie Esteoulle Claude Ling Germain Brou Dr. Nicolas Anton Thierry Vandamme Dr. Marc-André Delsuc Dr. Dominique Bonnet Prof. Bruno Kieffer 《Chembiochem : a European journal of chemical biology》2021,22(4):657-661
Conjugation of the bioactive apelin-17 peptide with a fluorocarbon chain results in self-organization of the peptide into micelles. Fluorine NMR spectroscopy studies show that the fluoropeptide‘s micelles are monodisperse, while proton NMR indicates that the peptide moiety remains largely disordered despite micellization. A very fast exchange rate is measured between the free and micellar states of the peptide which enables the number of molecules present in the micelle to be estimated as 200, in agreement with values found by dynamic light scattering measurements. 相似文献
17.
TiAl coupons were dipped in a low-concentration phosphoric acid solution, air dried, then heated up to 700 °C or 800 °C before discontinuous oxidation under laboratory air at these temperatures. At the end of the heating ramp, surfaces of TiAl samples were covered by a layer made of a pyrophosphate compound, resulting from reaction between the deposited acid and oxidized titanium. This layer strongly adhered to the substrate surface and allowed to greatly improve the resistance of TiAl to oxidation. After a certain time, a transition period occurred during which pyrophosphate compound disappeared to be changed into TiO2 rutile. For experiments carried on at 800 °C, it was shown that the phosphorus coming from the pyrophosphate group was present in this titanium oxide and that sample mass gain was still lowered. Performed analyses (XRD, SEM, EDS, μ-Raman spectroscopy) allowed to propose an overall mechanism to account for the “phosphorus effect”. 相似文献
18.
Sylvain‐Didier B. Kouame 《Lubrication Science》2014,26(2):117-130
Temperature‐programmed oxidation (TPO) was used to investigate the mechanism of lubricant‐derived deposit formation on metal surfaces. The relationship between the crystalline structures of different carbonaceous specimens, along with their chemical reactivity, was used to distinguish between more reactive and less reactive lubricant deposits. Multiple CO2 peaks obtained were attributed to differences in the oxidation reactivity of the deposits with respect to their structural characteristics. Findings from this work suggest that as deposits evolve, they become more complex (varied) due to loss of O and H atoms during a carbonisation‐type process. As these deposits undergo visible changes over time (lacquer deposit transforming into dark carbon), the average peak temperature (weighted average oxidation temperature) monotonically increases. Characterisations of lubricant deposits by TPO indicate that the global change in carbonaceous structure proceeds across the deposits in a uniform layer deposition model. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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BD Kouame H Lardy S Michalak A Lacombe C Mercier M Robert 《Canadian Metallurgical Quarterly》1998,32(6-7):363-366
The authors report the first case of bladder paraganglioma in a child admitted to their department successfully treated by partial cystectomy. The diagnosis was established histologically, after failure of clinical diagnosis. Retrospectively' the authors think that preoperative diagnosis should have been possible and emphasize the importance of a thorough clinical examination. 相似文献
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Didier-Axel Sess-Tchotch Kra Brou Didier Kedjebo Betty Meuwiah Faulet Angelique Fontana-Tachon Pascaline Alter Noël Durand Joël Grabulos Didier Montet Tagro Simplice Guehi 《Food Analytical Methods》2018,11(11):3138-3146
A simple, fast and ecological analytical method using a semi-automatic fat extractor and HPLC-FLD (fluorescence detection) for determination of polycyclic aromatic hydrocarbon markers i.e. benzo(a)anthracene (BaA), chrysene (Chr), benzo(a)pyrene (BaP) and benzo(b)fluoranthene (BbF) in cocoa butter has been validated. Validation’s procedure performed out in concordance with French standard NF V03-110 (2010) was based on existing polycyclic aromatic hydrocarbon (PAH) determination methods in various smoked foodstuffs and edible vegetable oils. Determination of correlation coefficients for specific PAHs ranged from 0.9992 to 0.9998. Respective values of limits of detection were 0.010, 0.011, 0.033 and 0.029 μg kg?1 and those of quantification were 0.035, 0.038, 0.111 and 0.098 μg kg?1 for BaA, Chr, BbF and BaP. Both values of repeatability and intermediary precision tests coefficients of variation were less than 5%. Recovery scores of four PAH markers matched EU standard 836/2011 recommendations. Sum of four PAH markers (BaA, Chr, BbF, BaP) contents varied from 5.42?±?0.58 to 11.37?±?0.01 μg kg?1 whereas those of BaP was comprised between 0.26?±?0.00 and 1.75?±?0.13 μg kg?1 in 20 cocoa butter samples extracted from raw cocoa bean stored at Ivorian cocoa farmer levels. 相似文献