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BACKGROUND: In many cases inflammatory bowel disease is accompanied by extraintestinal manifestations. This results in lowering of live quality. The aim of this study was to gather data retrospectively about initial symptoms, extraintestinal manifestations and course of pregnancy in a large unselected population with inflammatory bowel disease in South Germany. PATIENTS AND METHODS: Data from 1975 to 1989 (392 patients) were analyzed and partially compared with data from 1992 to 1995 (211 patients). RESULTS: Patients with Crohn's disease in average have been 25 years old at the time point of initial symptoms, whereas the age of ulcerative colitis patients was 30 years (p < 0.0001). The number of Crohn's disease patients with a long interval between initial symptoms and diagnosis (> 1 year) was significantly decreased in the second population (50% vs 38%; p < 0.05). Dominant initial symptoms in Crohn's disease were indisposition, abdominal pain and nonbloody diarrhea in contrast to ulcerative colitis which manifested mostly with bloody diarrhea. Extraintestinal manifestations occurred in 76% of patients with Crohn's disease and 64.6% with ulcerative colitis. Complications during the course of pregnancy have been detected in 40.5% in Crohn's disease and 60% in ulcerative colitis. CONCLUSION: A better knowledge of initial symptoms and extraintestinal manifestations in inflammatory bowel disease can help to decrease the interval between initial symptoms and the diagnosis. Pregnancy in patients with inflammatory bowel disease needs to be treated with special care. 相似文献
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A.?Torres A.?Guarda N.?Moraga J.?Romero M.?J.?GalottoEmail author 《European Food Research and Technology》2012,234(4):713-722
The specific migration of Octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate (I-1076) from three-layer low-density
polyethylene plastic films into a fatty food simulant was studied. The film samples, having a symmetrical structure with a
contaminated core layer and virgin outer layers, were developed with a known amount of a selected migrant in the inner layer.
A phenomenological model based on a resistances-in-series was resolved through the regula falsi algorithm according to a routine
that considers the income of the structural parameters of the system and experimental conditions in which migration testing
was performed. The model’s accuracy in predicting migration was demonstrated successfully by comparing simulated results to
experimental data. The computer program, developed as a total solution package for migration problems, can be applied not
only to multilayer structures made with the same type of plastics but also to structures with different plastics. 相似文献
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Francisco J. Rodríguez Alejandra Torres Ángela Peñaloza Hugo Sepúlveda María J. Galotto Abel Guarda 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2014,31(3):342-353
Nanocomposites based on biopolymers have been recognised as potential materials for the development of new ecofriendly food packaging. In addition, if these materials incorporate active substances in their structure, the potential applications are much higher. Therefore, this work was oriented to develop nanocomposites with antimicrobial activity based on cellulose acetate (CA), a commercial organoclay Cloisite30B (C30B), thymol (T) as natural antimicrobial component and tri-ethyl citrate (TEC) as plasticiser. Nanocomposites were prepared by a solvent casting method and consisted of 5% (w/w) of C30B, 5% (w/w) of TEC and variable content of T (0%, 0.5% and 2% w/w). To evaluate the effect of C30B into the CA matrix, CA films without this organoclay but with T were also prepared. All nanocomposites showed the intercalation of CA into the organoclay structure; furthermore this intercalation was favoured when 2% (w/w) of T was added to the nanocomposite. In spite of the observed intercalation, the presence of C30B inside the CA matrices increased the opacity of the films significantly. On the other hand, T showed a plasticiser effect on the thermal properties of CA nanocomposites decreasing glass transition, melting temperature and melting enthalpy. The presence of T in CA nanocomposites also allowed the control de Listeria innocua growth when these materials were placed in contact with this Gram-positive bacterium. Interestingly, antimicrobial activity was increased with the presence of C30B. Finally, studies on T release showed that the clay structure inside the CA matrix did not affect its release rate; however, this nanofiller affected the partition coefficient KP/FS which was higher to CA nanocomposites films than in CA films without organoclay. The results obtained in the present study are really promising to be applied in the manufacture of food packaging materials. 相似文献
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P. A. Ulloa J. Vidal C. Lopéz de Dicastillo F. Rodriguez A. Guarda R. M. S. Cruz M. J. Galotto 《应用聚合物科学杂志》2019,136(8):47090
Active films (AFs) using poly(lactic acid) (PLA) as a polymeric matrix containing various propolis concentrations (5, 8.5, and 13%) as the active agent (AA) were developed using a casting method. The purpose was to determine the effects of the incorporation of AA on the physical properties of the films and to evaluate the antioxidant and antimicrobial activities. Tensile strength and elastic modulus of the AFs decreased relative to the control (PLA without AA). Introducing the active substances from propolis into the PLA also affected its thermal properties (glass transition). Adding AAs to the polymer generated more opacity with a green-yellowish color compared to the control. In addition, AFs exhibited reduced water vapor permeability as the AA concentration increased. Biodegradation assay showed that the AFs degraded faster than the control. AFs exhibited antioxidant activity, which was measured as the ability to scavenge free radicals (2,2-diphenyl-1-picrylhydrazyl and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonate)), due to the presence of bioactive compounds (phenolics). Antimicrobial activity was evaluated against Escherichia coli and showed a reduction over 4-log cycles. Therefore, incorporation of propolis is a useful strategy for the development of active packaging with antioxidant and antimicrobial effects, which increase the shelf life of food products. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47090. 相似文献
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Carol López de Dicastillo Julio Bruna Alejandra Torres Nancy Alvarado Abel Guarda María José Galotto 《应用聚合物科学杂志》2017,134(15)
In this study, antioxidant food‐packaging materials were developed by the incorporation of merkén, an aboriginal Chilean spice, into a biodegradable polymer matrix, poly(lactic acid). Antioxidant activity assays and the phenolic content of merkén showed interesting results compared to other condiments, such as oregano and parsley. Active materials with merkén at 3 and 5 wt % were successfully obtained by extrusion. Chromatographic analysis revealed the chemical composition of merkén, and its active material was based on interesting flavonoids and organic acids, such as catechin, myricetin, and gallic and ellagic acids. Scanning electron micrographs showed that the merkén particles accumulated in aggregates; this resulted in an increase in the permeability values and a reduction in the crystallinity and mechanical properties of the polymer matrix. Nevertheless, these materials presented interesting antioxidant activities as radical scavengers on aqueous food simulants. The kinetics of release was dependent on the type of food and the nominal content of merkén in the films. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44692. 相似文献
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Maurizio Sansotera Walter Navarrini Giuseppe Resnati Pierangelo Metrangolo Antonino Famulari Claudia L. Bianchi P. Antonio Guarda 《Carbon》2010,48(15):4382-4390
Superhydrophobic conductive carbon blacks were prepared by covalent bonding of perfluorocarbon and perfluoropolyether chains on the conductive carbon black surface. Perfluorodiacyl and perfluoropolyether peroxides were used as reagents for the chemical treatment. Their thermal decomposition produced respectively, perfluoroalkyl and perfluoropolyether radicals that directly bonded the polycyclic aromatic structure of carbon black surface. Measurements of contact angles with water on molded pellets made with carbon black powder demonstrated that water droplets were enduringly stable on the treated carbon blacks. Contact angle values were significantly high, exceeding the superhydrophobicity threshold. On the contrary, the droplets were adsorbed in few seconds by the native carbon black. Conductivity measurements showed that the covalent linkage of fluorinated chains weakly modified the electrical properties of the conductive carbon black, even if the surface properties changed so deeply. The relationship between the linkage of fluorinated chains and the variations of physical–chemical properties were studied combining electron spectroscopy, resistivity measurements, X-ray diffraction, scanning electron microscopy, surface area analysis and thermal gravimetric analysis. The superhydrophobic conductive carbon blacks were compared with a superhydrophobic carbon black obtained by direct fluorination of conductive carbon black with elemental fluorine, F2. 相似文献
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Privacy and data protection are pivotal issues in nowadays society. They concern the right to prevent the dissemination of sensitive or confidential information of individuals. Many studies have been proposed on this topic from various perspectives, namely sociological, economic, legal, and technological. We have recognized the legal perspective as being the basis of all other perspectives. Actually, data protection regulations set the legal principles and requirements that must be met by organizations when processing personal data. The objective of this work is to provide a reference base for the development of methodologies tailored to design privacy-aware systems to be compliant with data protection regulations. 相似文献