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排序方式: 共有845条查询结果,搜索用时 12 毫秒
31.
Maria Dolores Pastor Ana Nogal Sonia Molina-Pinelo Ricardo Meléndez Beatriz Romero-Romero Maria Dolores Mediano Jose L. López-Campos Rocío García-Carbonero Amparo Sanchez-Gastaldo Amancio Carnero Luis Paz-Ares 《International journal of molecular sciences》2013,14(2):3440-3455
Lung cancer (LC) and chronic obstructive pulmonary disease (COPD) commonly coexist in smokers, and the presence of COPD increases the risk of developing LC. Cigarette smoke causes oxidative stress and an inflammatory response in lung cells, which in turn may be involved in COPD and lung cancer development. The aim of this study was to identify differential proteomic profiles related to oxidative stress response that were potentially involved in these two pathological entities. Protein content was assessed in the bronchoalveolar lavage (BAL) of 60 patients classified in four groups: COPD, COPD and LC, LC, and control (neither COPD nor LC). Proteins were separated into spots by two dimensional polyacrylamide gel electrophoresis (2D-PAGE) and examined by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF/TOF). A total of 16 oxidative stress regulatory proteins were differentially expressed in BAL samples from LC and/or COPD patients as compared with the control group. A distinct proteomic reactive oxygen species (ROS) protein signature emerged that characterized lung cancer and COPD. In conclusion, our findings highlight the role of the oxidative stress response proteins in the pathogenic pathways of both diseases, and provide new candidate biomarkers and predictive tools for LC and COPD diagnosis. 相似文献
32.
The Planar Laser Induced Exciplex Fluorescence (PLIEF) technique is widely used to visualize and measure the fuel concentration fields in both liquid and vapor phases of DI Diesel sprays. However, the real limitations of the PLIEF technique in Diesel sprays and the accuracy of the results obtained are still a source of controversy. In this work, a complete methodology for maximum penetration and fuel concentration measurements in evaporating conditions in Diesel sprays has been developed and the reliability of the results obtained has been investigated. The methodology includes new procedures for measuring both liquid and vapor phases, adapting, when necessary, correlations available in the literature for calibration.
An experimental matrix of nine test points with different injection pressures and combustion chamber densities has been performed. A critical analysis of the different error sources for proper quantification is made. Results have shown that macroscopic features can be accurately determined using the PLIEF technique, but for fuel concentration measurements special considerations have to be taken into account, particularly in the regions where liquid and vapor coexist. 相似文献
33.
Alfredo Carbonell‐Verdu David Garcia‐Sanoguera Amparo Jordá‐Vilaplana Lourdes Sanchez‐Nacher Rafael Balart 《应用聚合物科学杂志》2016,133(27)
The use of epoxidized cottonseed oil as plasticizer for poly(vinyl chloride) was studied. The plasticizer content was set to 70 phr and the optimum isothermal curing conditions were studied in the temperature range comprised between 160 and 220 °C with varying curing times in the 7.5–17.5 min range. The influence of the curing conditions on overall performance of cured plastisols was followed by the evolution of mechanical properties (tensile tests with measurements of tensile strength, elongation at break, and modulus), change in color, surface changes of fractured samples by scanning electron microscopy (SEM), thermal transitions by differential scanning calorimetry, and migration in n‐hexane. The optimum mechanical features of cured plastisols are obtained for curing temperatures in the 190–220 °C range. For these curing conditions, fractography analysis by SEM gives evidences of full curing process as no PVC particles and free plasticizer can be found. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43642. 相似文献
34.
Benito Alcaide Pedro Almendros Ana M. Gonzlez Amparo Luna Sagrario Martínez‐Ramírez 《Advanced Synthesis \u0026amp; Catalysis》2016,358(12):2000-2006
A convenient ligand‐free catalytic system has been developed for the chemoselective cyclization reaction of various α‐allenol derivatives by palladium nanoparticles (PdNPs) in an aqueous reaction medium.
35.
M.C. MesaP.B. Oliete V.M. OreraJ.Y. Pastor A. MartínJ. LLorca 《Journal of the European Ceramic Society》2011,31(7):1241-1250
Eutectic rods of Al2O3-Er3Al5O12 were grown by directional solidification using the laser-heated floating zone method at rates in the range 25-1500 mm/h. Their microstructure and mechanical properties (hardness, toughness and strength) were investigated as a function of the growth rate. A homogeneous and interpenetrated microstructure was found in most cases, and interphase spacing decreased with growth rate following the Hunt-Jackson law. Hardness increased slightly as the interphase spacing decreased while toughness was low and independent of the microstructure. The rods presented very high bending strength as a result of the homogeneous microstructure, and their strength increased rapidly as the interphase spacing decreased, reaching a maximum of 2.7 GPa for the rods grown at 750 mm/h. The bending strength remained constant up to 1300 K and decreased above this temperature. The relationship between the microstructure and the mechanical properties was established from the analysis of the microstructure and of the fracture mechanisms. 相似文献
36.
In this work it is presented a model of alkyllithium initiated anionic polymerization. The model was developed from the balance
of living polymer chains of each chain length, taking into account the participation of molecular aggregates of lithium compounds
in initiation and propagation reactions. The model was applied to styrene polymerization in cyclohexane, where the known but
not explained acceleration of initiation reaction takes place. The well established reaction order respect to polystyryllithium
in propagation reaction allowed some simplification of the model. A more simplified model of three parameters was also developed
by using apparent kinetic constants. As part of the work, the apparent propagation constants were determined experimentally
and are reported in the Arrhenius equation form. The remainder kinetic parameters used in the model were assumed or fitted
to experimental data and are described into the work. The model allows explaining acceleration of the initiation reaction
and experimental data of molecular weight averages (Mn, Mw and Mz) during the polymerization. The three-parameter model was only able to explain the acceleration of initiation reaction and
monomer conversion data. 相似文献
37.
Rosemary (Rosmarinus officinalis) is mainly known for its cooking qualities, but it possesses an essential oil with pharmacological properties. Moreover, this plant was the start of forest fires in Provence, France. The presence of biopolymers can contribute to electrical energy production by biomass combustion. The aim of this work was to study a stalk of rosemary during its biological cycle (November 1998 to June 1999). The chemical analysis (water, mineral ashes, cellulose, lignin, holocellulose, and extractives) showed few variations during this period. Leaves and branches differentiated themselves according to their chemical composition. Analyzed by chromatography gas–liquid chromatography/mass spectroscopy (GC‐MS) and gas–liquid chromatography/flam ionization detector (GC‐FID), the essential oil of this rosemary had a high level of camphor (30–45%), which could be used in new therapeutics (cardiac and respiratory analeptic). Finally, the simultaneous thermal analysis (DTA‐TG) was run on the fresh plants and the dried powdered samples. Several kinetic constants of the biopolymers had been computed: activation energies of cellulose and holocellulose. During heating, the rosemary's lignin decomposed more than others plants, thereby increasing the fire risks. The chemical, chromatographic, and thermal analysis run on the rosemary could be applied on other species in the Mediterranean basin. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 747–756, 2002 相似文献
38.
A. R. Carella C. Alonso J. C. Merino J. M. Pastor 《Polymer Engineering and Science》2002,42(11):2172-2181
A systematic approach was used to study the effect of the process variables that control bonding of the injected melt to the previously injected parts, in sequential injection molding of thermoplastic polymers. Three polymer pairs were sequentially injected in a mold with the same geometry, in a range of mold and injected melt temperatures, and packing pressure conditions. Standard Peel Tests were conducted on injected samples to measure the resulting bonding strength. The analysis of the experimental results allows the quantification of the relative importance of the processing parameters involved. A direct correlation is found between the calculated interface temperature and the packing pressure needed for bonding. A generalized procedure is proposed to establish the processing conditions, which allow polymerpolymer bonding to be optimized. 相似文献
39.
Briggs K Cases M Heard DJ Pastor M Pognan F Sanz F Schwab CH Steger-Hartmann T Sutter A Watson DK Wichard JD 《International journal of molecular sciences》2012,13(3):3820-3846
There is a widespread awareness that the wealth of preclinical toxicity data that the pharmaceutical industry has generated in recent decades is not exploited as efficiently as it could be. Enhanced data availability for compound comparison ("read-across"), or for data mining to build predictive tools, should lead to a more efficient drug development process and contribute to the reduction of animal use (3Rs principle). In order to achieve these goals, a consortium approach, grouping numbers of relevant partners, is required. The eTOX ("electronic toxicity") consortium represents such a project and is a public-private partnership within the framework of the European Innovative Medicines Initiative (IMI). The project aims at the development of in silico prediction systems for organ and in vivo toxicity. The backbone of the project will be a database consisting of preclinical toxicity data for drug compounds or candidates extracted from previously unpublished, legacy reports from thirteen European and European operation-based pharmaceutical companies. The database will be enhanced by incorporation of publically available, high quality toxicology data. Seven academic institutes and five small-to-medium size enterprises (SMEs) contribute with their expertise in data gathering, database curation, data mining, chemoinformatics and predictive systems development. The outcome of the project will be a predictive system contributing to early potential hazard identification and risk assessment during the drug development process. The concept and strategy of the eTOX project is described here, together with current achievements and future deliverables. 相似文献
40.
The two-stage isomerization isotherms of poly(ethylene Terephthalate) have been followed through microhardness analysis. A great variation in microhardness values seems to prove the increase of the strength and stiffness of the samples produced by the secondary isomerization. A smaller variation is observed for the primary isomerization. 相似文献