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31.
Alves RM Pereira BF Pitol DL Senhorini JA Rocha Rde C Caetano FH 《Microscopy research and technique》2012,75(5):615-619
The adipose fin is small, nonpared, and usually located medially between the dorsal and caudal fin. Its taxonomic occurrence is very restrict; thus, it represents an important trace for taxon distinction. As it does not play a known vital physiological roll and it is easily removed, it is commonly used in marking and recapture studies. The present study characterizes the adipose fin of Prochilodus lineatus, as it is poorly explored by the literature. The adipose fin consists basically of a loose connective core, covered by a stratified epithelium supported by collagen fibers. At the epithelium, pigmented cells and alarm substance cells are found. Despite the name, adipocytes or lipid droplets are not observed on the structure of the fin. 相似文献
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Mortality due to lung, laryngeal and bladder cancer in towns lying in the vicinity of combustion installations 总被引:1,自引:0,他引:1
Javier García-Pérez Marina Pollán Elena Boldo Beatriz Pérez-Gómez Nuria Aragonés Virginia Lope Rebeca Ramis Enrique Vidal Gonzalo López-Abente 《The Science of the total environment》2009,407(8):2593-2602
Background
Installations that burn fossil fuels to generate power may represent a health problem due to the toxic substances which they release into the environment.Objectives
To investigate whether there might be excess mortality due to tumors of lung, larynx and bladder in the population residing near Spanish combustion installations included in the European Pollutant Emission Register.Methods
Ecologic study designed to model sex-specific standardized mortality ratios for the above three tumors in Spanish towns, over the period 1994-2003. Population exposure to pollution was estimated on the basis of distance from town of residence to pollution source. Using mixed Poisson regression models, we analyzed: risk of dying from cancer in a 5-kilometer zone around installations that commenced operations before 1990; effect of type of fuel used; and risk gradient within a 50-kilometer radius of such installations.Results
Excess mortality (relative risk, 95% confidence interval) was detected in the vicinity of pre-1990 installations for lung cancer (1.066, 1.041-1.091 in the overall population; 1.084, 1.057-1.111 in men), and laryngeal cancer among men (1.067, 0.992-1.148). Lung cancer displayed excess mortality for all types of fuel used, whereas in laryngeal and bladder cancer, the excess was associated with coal-fired industries. There was a risk gradient effect in the proximity of a number of installations.Conclusions
Our results could support the hypothesis of an association between risk of lung, laryngeal and bladder cancer mortality and proximity to Spanish combustion installations. 相似文献34.
Sandra A. Mayén-Hernández Gerardo Torres-Delgado Rebeca Castanedo-Pérez Mario Gutiérrez Villarreal Alfredo Cruz-Orea Julio G. Mendoza Alvarez Orlando Zelaya-Angel 《Journal of Materials Science: Materials in Electronics》2007,18(11):1127-1130
ZnO + Zn2TiO4 thin films were obtained by the sol–gel method using precursor solutions with different Ti/Zn ratios in the 0.18–2.13 range.
The films were deposited on glass substrates and annealed in an open atmosphere at 550 °C. The oxide was characterized by
X-ray diffraction and photoacoustic (PA) spectroscopy. The films were constituted of polycrystalline ZnO for the lowest Ti/Zn
ratio (0.18), polycrystalline Zn2TiO4 for the 0.70 and 1.0 ratios, and mixes of both oxides for the intermediate ratios (0.32 and 0.50). For the highest ratios
studied (1.44 and 2.13), the films were amorphous. The energy band gap (Eg) values were determined from optical absorption spectra, measured by means of the PA technique spectra. Eg varied in the 3.15 eV (ZnO) to 3.70 eV (Zn2TiO4) range. 相似文献
35.
Validation of a Single-Extraction Procedure for Sequential Analysis of Vitamin E, Cholesterol, Fatty Acids, and Total Fat in Seafood 总被引:1,自引:0,他引:1
Rebeca Cruz Susana Casal Eulália Mendes Ana Costa Catarina Santos Simone Morais 《Food Analytical Methods》2013,6(4):1196-1204
Food lipid major components are usually analyzed by individual methodologies using diverse extractive procedures for each class. A simple and fast extractive procedure was devised for the sequential analysis of vitamin E, cholesterol, fatty acids, and total fat estimation in seafood, reducing analyses time and organic solvent consumption. Several liquid/liquid-based extractive methodologies using chlorinated and non-chlorinated organic solvents were tested. The extract obtained is used for vitamin E quantification (normal-phase HPLC with fluorescence detection), total cholesterol (normal-phase HPLC with UV detection), fatty acid profile, and total fat estimation (GC-FID), all accomplished in <40 min. The final methodology presents an adequate linearity range and sensitivity for tocopherol and cholesterol, with intra- and inter-day precisions (RSD) from 3 to 11 % for all the components. The developed methodology was applied to diverse seafood samples with positive outcomes, making it a very attractive technique for routine analyses in standard equipped laboratories in the food quality control field. 相似文献
36.
Luana Fernandes Susana Casal Rebeca Cruz José Alberto Pereira Elsa Ramalhosa 《Food research international (Ottawa, Ont.)》2013,50(1):161-166
To increase the potential and better exploring of grape seeds that are an important wine-industrial waste, oils of ten traditional Portuguese grape varieties were evaluated in relation to their vitamin E content (tocopherols and tocotrienols), fatty acid profile, as well as, antioxidant properties. Our results showed that the grape-seed oils were a good source of γ-tocotrienol (499–1575 mg/kg), α-tocopherol (85.5–244 mg/kg) and α-tocotrienol (69–319 mg/kg). Concerning fatty acid profile, linoleic (C18:2cc), oleic (C18:1), palmitic (C16:0) and stearic (C18:0) acids were the predominant. Grape-seed oils demonstrated to be a good source of polyunsaturated fatty acids (PUFAs) (63.64–73.53%), whereas monounsaturated fatty acid (MUFA) and saturated fatty acid (SFA) ranged between 14.19–21.29% and 11.64–14.94%, respectively. Interesting values of DPPH and ABTS radical scavenging activities were also obtained. This study demonstrated that these seeds may be reused and their oils incorporated in other food products, taking into account the compounds with positive effects on human health that are present in their composition. 相似文献
37.
Armando Burgos‐Hernndez Ralph L Price Karen Jorgensen‐Kornman Rebeca Lpez‐García Henry Njapau Douglas L Park 《Journal of the science of food and agriculture》2002,82(5):546-552
The decontamination of aflatoxin B1(AFB1)‐contaminated corn, which is required if the corn is to be suitable for alternative use, by an ammoniation–fermentation integrated process was studied. This process could be used for the production of fuel ethanol from aflatoxin‐containing corn. Different concentrations (0.25, 0.50, 1.00, 1.5 and 2.0% w/w) of ammonium persulphate were tested in the detoxification of AFB1‐contaminated corn during fermentation. In order to increase the decontamination of corn, 0.5 and 1.0% (w/w) azodicarbonamide, benzoyl peroxide and hydrogen peroxide were tested. Peroxides were added at three different stages of the fermentation process: liquefaction, saccharification and fermentation. Levels of AFB1 and ethanol were determined after each fermentation process. Treated corn was tested for mutagenic potential using the Ames test with TA100 tester strain and pure AFB1 as positive control. Addition of 2.0% (w/w) ammonium persulphate caused the highest level of decontamination without affecting ethanol production. Addition of peroxides did not significantly (P < 0.05) increase ethanol production or significantly (P < 0.05) improve the decontamination process. The best processes for decontamination of corn and for ethanol production included the addition of 2.0% (w/w) ammonium persulphate for both and of 1.0 and 0.5% (w/w) benzoyl peroxide respectively. All treated corn samples showed no mutagenic potential. Possible industrial use of these processes is discussed. © 2002 Society of Chemical Industry 相似文献
38.
Marcela L. Martínez Ma. Gabriela Bordón Rebeca L. Lallana Pablo D. Ribotta Damián M. Maestri 《Food and Bioprocess Technology》2017,10(6):1113-1121
Box-Behnken designs were used to optimize a process for sesame oil extraction by screw-pressing at low temperature (50 °C). Experimental designs included seed moisture content (SMC), pressing speed (PS), and restriction die (RD) as the main processing parameters. Extractions at pilot plant scale showed a peak in oil recovery (OR, 71.1 ± 2.80%) at 12.3% SMC, 4 mm RD, and 20 rpm PS. Theoretical models were scanned against experimental data in order to scale up the proposed oil extraction process to industrial scale. A fitted model for OR showed a maximum predicted value similar to the highest experimental value (74.4 ± 1.23%) under the following conditions: 8.03% SMC, 10 mm RD, and 20 rpm PS. Chemical quality parameters of oils obtained at both pilot and industrial scales were in the ranges stated in Codex (FAO/WHO) standards for non-refined sesame oil. 相似文献
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