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排序方式: 共有618条查询结果,搜索用时 15 毫秒
21.
Chiara Cipollina Andreina Bruno Salvatore Fasola Marta Cristaldi Bernardo Patella Rosalinda Inguanta Antonio Vilasi Giuseppe Aiello Stefania La Grutta Claudia Torino Elisabetta Pace 《International journal of molecular sciences》2022,23(3)
Exposure of the airways epithelium to environmental insults, including cigarette smoke, results in increased oxidative stress due to unbalance between oxidants and antioxidants in favor of oxidants. Oxidative stress is a feature of inflammation and promotes the progression of chronic lung diseases, including Chronic Obstructive Pulmonary Disease (COPD). Increased oxidative stress leads to exhaustion of antioxidant defenses, alterations in autophagy/mitophagy and cell survival regulatory mechanisms, thus promoting cell senescence. All these events are amplified by the increase of inflammation driven by oxidative stress. Several models of bronchial epithelial cells are used to study the molecular mechanisms and the cellular functions altered by cigarette smoke extract (CSE) exposure, and to test the efficacy of molecules with antioxidant properties. This review offers a comprehensive synthesis of human in-vitro and ex-vivo studies published from 2011 to 2021 describing the molecular and cellular mechanisms evoked by CSE exposure in bronchial epithelial cells, the most used experimental models and the mechanisms of action of cellular antioxidants systems as well as natural and synthetic antioxidant compounds. 相似文献
22.
Inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis, is a serious, costly, and persistent health problem with an estimated prevalence in Western countries around 0.5% of the general population; its socioeconomic impact is comparable with that for chronic diseases such as diabetes. Conventional treatment involves escalating drug regimens with concomitant side effects followed, in some cases, by surgical interventions, which are often multiple, mainly in Crohn's disease. The goal of finding a targeted gut‐specific immunotherapy for IBD patients is therefore an important unmet need. However, to achieve this goal we first must understand how dendritic cells (DC), the most potent antigen present cells of the immune system, control the immune tolerance in the gastrointestinal tract and how their properties are altered in those patients suffering from IBD. In this review, we summarize the current available information regarding human intestinal DC subsets composition, phenotype, and function in the human gastrointestinal tract describing how, in the IBD mucosa, DC display pro‐inflammatory properties, which drive disease progression. A better understanding of the mechanisms inducing DC abnormal profile in IBD may provide us with novel tools to perform tissue specific immunomodulation. 相似文献
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24.
AbstractA latent heat thermal energy storage system with phase change material (PCM) is numerically studied. To enhance the heat transfer inside the system, a highly conductive metal foam is employed with ceramic nanoparticles. The latter method of enhancement leads to a new class of material called Nano-PCM. The system under investigation is a 70-L tank filled up with pure PCM or Nano-PCM and several pipes are situated where the heat transfer fluid (HTF) flows. The pipe surfaces are assumed at constant temperature above the PCM melting temperature to simulate the heat transfer from the HTF. The enthalpy-porosity theory is applied to simulate the PCM phase change, while the porous media formulation is assumed to describe the metal foam behavior. The nano-PCM is modeled with single-phase model where the properties are the weighted-average between the fluid base and the nanoparticles. The simulations are accomplished for charging-discharging process at different porosities and nanoparticle concentration. The results are given in term of average melting fraction evolution, average temperature as function of time, average stored energy. The metal foam significantly improves the heat transfer between PCM and HTF respect to the addition of nanoparticles, reducing the charging and discharging time more than one order of magnitude. 相似文献
25.
This paper presents a model of approach for agroindustrial development utilizing geothermal energy in an agriculturally based tropical developing country. Presented is the complexity of patterns in raw materials productivity, demand and the present problems of preserving their quality from biological deterioration thru drying.Utilization of a geothermal agroindustrial estate have to be carefully studied and programmed in reply to an almost constant heat demand profile consistent with seasonal available raw materials. This study uses the Tongonan Geothermal Field in Leyte Island as the model for presentation. 相似文献
26.
Rafael Bernardo Carmona-Paredes Rafael Bernardo Carmona-Benítez 《Water Resources Management》2018,32(5):1651-1673
The rapid population growth of cities in developing countries (DC) make difficult to distribute the available potable water (PW) with equality. The distribution problem arises from an insufficient amount of PW and because cities water distribution systems (WDS) are not efficient. The novelty of this paper is a self-tuning controller (STC) proposed to manage, along the day, the pressure of water through the nodes of a WDS. It means, pressure management (PM) is proposed to control water levels (WLs) in householders tanks (HTs). The objective is to satisfy with equality the PW demand at different zones of a city forcing the flow of water by managing the pressure. The proposed STC performance is tested on the digital simulator developed to characterize the hydraulic operation of a WDS. The dynamic behaviour of the WDS is determined by the variation of the WL in the tanks of the WDS when water is supplied or extracted from them. The WDS of Mexico City is analysed and the proposed STC is applied to a simplified WDS. The results allow to conclude that the proposed STC could become a supporting tool for the decision making of WDS operators. 相似文献
27.
L. Biasetto P. Zanonato P. Di Bernardo A. Andrighetto 《Journal of Nuclear Materials》2010,404(1):68-186
Uranium carbide dispersed in graphite was produced under vacuum by means of carbothermic reduction of different uranium oxides (UO2, U3O8 and UO3), using graphite as the source of carbon. The thermal process was monitored by mass spectrometry and the gas evolution confirmed the reduction of the U3O8 and UO3 oxides to UO2 before the carbothermic reaction, that started to occur at T > 1000 °C. XRD analysis confirmed the formation of α-UC2 and of a minor amount of UC. The morphology of the produced uranium carbide was not affected by the oxides employed as the source of uranium. 相似文献
28.
Deborah Oliveira De Fusco Leonardo Lucas Madaleno Vanildo Luiz Del Bianchi Aline da Silva Bernardo Rafael Roberto Assis Gustavo Henrique de Almeida Teixeira 《International Journal of Food Science & Technology》2019,54(7):2416-2424
Alcohol-free beer with isotonic properties is getting more popular and its production can be carried out by different production strategies; however, interrupted fermentation is still a challenge. Therefore, the objective of this study was to develop a low-alcohol isotonic beer (<0.5% v/v) by interrupted fermentation. Moreover, the major objective is to compare the developed product to commercial beverages (sports drinks, ‘Pilsen' regular beer, alcohol-free beers and low-alcohol isotonic beer). The beverages were evaluated based on pH, alcohol content (% v/v), total titratable acidity (mEq L−1), osmolality (mOsmol kg−1), bitterness International Bitterness Units, colour European Brewery Convention, total phenolic compounds (mg L−1 gallic acid), reducing and total sugars (%) and Na and K contents (mg L−1). The developed low-alcohol isotonic beer presented characteristics similar to sports drinks, with the advantage of being richer in phenolic compounds and suitable osmolality. Despite salts were added in its formulation, the grades attributed to all beers employed in the sensory evaluation, as well as the purchase intention did not present significant differences. 相似文献
29.
Proteolytic and lipolytic changes during the ripening of León raw cow's milk cheese, a Spanish traditional variety 总被引:1,自引:0,他引:1
Bernardo Prieto Inmaculada Franco Josefa González Prieto Ana Bernardo & Javier Carballo 《International Journal of Food Science & Technology》2002,37(6):661-671
Proteolytic and lipolytic changes were studied throughout ripening of five batches of León cow's milk cheese, a traditional variety made in the north of Spain. Total soluble nitrogen, non-protein nitrogen, oligopeptides nitrogen, amino nitrogen and ammonia nitrogen fractions increased slightly during the ripening process. The final values of these nitrogen fractions indicate that this cheese undergoes a very slight proteolysis as much in extent as in depth. This weak protein degradation is corroborated when the caseins and their degradation products were quantified by electrophoresis. β-Casein stayed practically intact throughout the ripening process and only 10% of αs -casein became degraded. The content of total free amino acids increased progressively but in a slightly increased way during ripening, reaching final average values of 592 mg (100 g)−1 of total solids. The most abundant free amino acid at the end of ripening was lysine, followed by leucine, glutamic acid, tryptophan, valine and phenylalanine. The acidity index of the fat values increased during ripening by a factor of 4.39. The final values of this parameter are in the range of those observed in other cow's milk cheeses ripened by bacteria. The content in total free fatty acids underwent an increase throughout ripening reaching final average values of 6669 ppm. The most abundant free fatty acid at the end of ripening was oleic acid followed by butyric and palmitic acids. The high content of short-chain fatty acids is outstanding, specially that of butyric acid. 相似文献
30.
Ceramic Microtubes from Preceramic Polymers 总被引:2,自引:0,他引:2
Paolo Colombo § Katia Perini Enrico Bernardo Tiziano Capelletti Giorgio Maccagnan 《Journal of the American Ceramic Society》2003,86(6):1025-1027
A novel process for the production of ceramic microtubes involving the microextrusion of preceramic polymers was studied. Microtubes with a wide range of inner and outer diameters and several centimeters long were produced from two silicone resins. A coextrusion approach was also used to extend the forming capability of the technique. The addition of carbon black resulted in electrically conductive silicon oxycarbide (SiOC) ceramic microtubes. SiOC microtubes possessed a high bending strength, ranging from ∼30–1100 MPa. 相似文献