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991.
Raquel Ibáñez Marco Peluso Armelle Munnia Sara Piro Carlos A. González Pilar Amiano M. J. Tormo Eva Ardanaz Aurelio Barricarte Antonio Berenguer M. Dolores Chirlaque Miren Dorronsoro Paula Jakszyn Nerea Larrañaga Carmen Martínez Carmen Navarro J. Ramón Quirós M. José Sánchez Antonio Agudo 《European Food Research and Technology》2009,229(4):549-559
The aim of this study was to assess the relationship between bulky DNA adducts in white blood cells (WBC) and lifestyle factors
in a sample from the Spanish cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC). 296 subjects
aged between 35 and 64 years, from five regions, were included. Food intake was estimated with a computerized version of dietary
history questionnaire. Daily intake of polycyclic aromatic hydrocarbons (PAH) was estimated using a database with information
on food content of potential carcinogens. Data on lifestyle and health factors were collected and DNA adducts measured using
the nuclease P1 32P-postlabelling technique. Geometric means of adducts were similar for men and women (4.11/109 and 3.94/109 nucleotides, respectively). Highest levels of adduct were observed in non-smokers and non-occupationally exposed. Meat intake,
oils and fats were associated with higher levels of adducts, but all non-statistically significant. Higher intakes of calcium,
sodium and phosphorus were associated with lower adducts levels. Summarising, our study shows that bulky adducts measured
by 32P-postlabelling in DNA from WBC do not correlate with the usual diet of healthy Spanish adults. Although it has been proposed
that diet be the main source of PAH in nonsmokers without occupational exposure, DNA adducts do not seem to be suitable biomarkers
of dietary PAH in general population. 相似文献
992.
Pine bark is a forest by-product that can be profitable as a source of polyphenols by its content in procyanidins. In this
work, barks of two varieties of pine (Pinus pinaster and P. radiata) were extracted with ethanol, and partially purified to obtain a fraction named FOW, that contained mainly flavan-3-ol monomers
and procyanidins oligomers. The mean degree of polymerization was 2.1 for pinaster (pOW) and 2.7 for radiata (rOW). FOWs were
fractionated on C18 Sep-Pak cartridges into three fractions for each variety by different organic solvents. The phenolic compositions of the
fractions were analyzed using HPLC with UV diode array detection and electrospray-ionization mass spectrometry. The compounds
identified were: catechin, dihydroquercetin, phenolic acids and their glucosides, procyanidins dimers, trimers and tetramers.
FOWs and their fractions were characterized in antioxidant power by DPPH and β-carotene methods. In the former assay, pOW
showed major effectiveness, with an antiradical specific activity of 46 units AR/mg procyanidins, whereas for the β-carotene
bleaching test rOW (78 ± 0.71%) gave the best inhibition result. Despite this fact the derived fractions, presenting similar
values, have advantages because the profile of their constituents is uniform for each one, and, hence, it is easier to investigate
their action for potential applications in both medical or food fields 相似文献
993.
Nicolas Terrade Ronan Noël Romain Couillaud Ramón Mira de Orduña 《Food research international (Ottawa, Ont.)》2009,42(3):363-367
Growth and activity of lactic acid bacteria is crucial for the production and quality of grape wines but studying their metabolism is difficult in wines or complex laboratory media because of the undefined substrate pools. This work presents a new chemically defined medium that meets the fastidious nutritional requirements of wine lactic acid bacteria and yields rapid and strong growth. The new medium is composed of 44 constituents and a precise protocol is provided for its preparation. Maximum specific growth rates and growth yields of the wine strains studied were comparable to those obtained in common laboratory media, and the new medium allows for various modifications, such as changing the medium pH to the wine range, addition of L-malic acid or utilization of different carbon sources while maintaining growth of wine lactic acid bacteria. The medium was successfully tested with 22 wine strains of the genera Oenococcus, Lactobacillus and Pediococcus. It is suggested that this chemically defined medium be considered for the investigation of the nutritional requirements and metabolism of wine lactic acid bacteria. 相似文献
994.
The effect of high pressure treatment (400 MPa, 10 min at 12 °C) on the volatile profile of Spanish dry-fermented sausage ‘salchichón’, packaged with or without aluminium foil in a multilayer polymeric bag, was investigated. The analysis of the volatile fraction was carried out by dynamic headspace extraction coupled to gas chromatography–mass spectrometry. Pressure-treated samples showed significantly higher levels of alcohols, aldehydes and alkanes and lower levels of two methylketones as compared with control samples. An intense migration was observed of compounds from the plastic material into the product, mainly linear and branched-chain alkanes, alkenes and benzene compounds. Most of these migrating compounds were significantly more abundant in pressurized samples than in untreated samples. 相似文献
995.
Carmen Martín-Hernández Marta Muñoz Cedric Daury Hans Weymuth Anna E.M. Kemmers-Voncken Vicente Corbatón Tomás Toribio Maria G.E.G. Bremer 《International Dairy Journal》2009,19(4):205-208
An immunochromatographic lateral-flow test dipstick test was developed for the fast detection of bovine rennet whey in liquid milk and milk powder. The test is based on the binding of casein glycomacropeptide (cGMP) by two specific anti-bovine κ-casein monoclonal antibodies and has a visual detection limit of around 15 ng mL?1 for cGMP and 1% (v/v) for rennet whey in milk using standards and spiked samples. The dipstick performance was evaluated in a collaborative trial using skim milk powder and raw, pasteurized and UHT milk. The suitability of the dipstick was demonstrated in comparison with gel permeation-high performance liquid chromotography and a colorimetric method, by analysing 60 raw milk samples collected from farms in Brazil. The dipstick results correlated well with the HPLC results and were more reliable than those obtained with the colorimetric method. The dipstick test correctly identified all raw milk samples with a rennet whey content above 4%. 相似文献
996.
This paper presents a special purpose linear programming algorithm to solve simple linear regression problems with least absolute value criterion. A special data structure is implemented and discussed in detail. Computational results are given. 相似文献
997.
998.
V Martínez Ibá?ez J Lloret J Broto C Margarit R Charco M Ezzedine J Boix-Ochoa 《Canadian Metallurgical Quarterly》1993,6(3):120-122
The lack of availability of pediatric donors for liver transplant has resulted in a high mortality rate among children awaiting transplantation, especially in patients weighing less than 10 kg. Knowledge of techniques of liver reduction allows liver transplantation in low-weight children with an adult liver graft, although with increased risk. The authors studied 70 pediatric liver transplants, 14.3% of whom received a reduced-size organ. Maximal difference between donor and recipient weight was 7.7. Segments II, III and IV (right hepatectomy) were transplanted in eight cases while segments II and III were transplanted in two cases. Transfusional requirements during the 48 hour postoperative period were not significantly different between patients with reduced-size liver and patients who received the full-size organ. There was not morbi-mortality secondary to surgical technique in reduced liver transplant group of patients. 相似文献
999.
The effect of ozone on the microbiological and sensory quality of poultry during refrigerated storage was studied. Ozone facilitates the oxidation of lipids, but no alterations were observed in the sensory characteristics of the meat. Ozone has a pronounced effect on the flora causing deterioration and hence prolongs the useful life of poultry in refrigerated storage. It was also observed to exert a powerful bactericidal effect on coliforms, Escherichia coli, and Salmonella. 相似文献
1000.