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671.
Investigation of the microbial ecology of Ciauscolo, a traditional Italian salami, by culture-dependent techniques and PCR-DGGE 总被引:2,自引:0,他引:2
Silvestri G Santarelli S Aquilanti L Beccaceci A Osimani A Tonucci F Clementi F 《Meat science》2007,77(3):413-423
The microbial ecology of 22 samples of commercially available Ciauscolo salami were investigated using a polyphasic approach, based on culture-dependent and -independent techniques. The viable counts of pathogen and hygiene indicator microorganisms highlighted the adequate application of good manufacturing practices, while the viable counts of the lactic acid bacteria, coagulase negative cocci, and yeasts showed dominance of the first of these microbial groups. Bacterial and fungal DNA were extracted directly from the salami and amplified by PCR, using two primer sets targeting the 16S and 28S rRNA genes, respectively. Denaturing gradient gel electrophoresis (DGGE) and sequencing of selected bands were used to investigate the microbial ecology of these Ciauscolo salami. The most frequently found bacterial species were Lactobacillus sakei and Lb. curvatus, while Debaryomyces hansenii was the prevalent yeast species detected. Cluster analysis of the DGGE profiles and calculation of biodiversity indices allowed the degree of microbial similarity across these salami to be determined. 相似文献
672.
Secades-Villa Roberto; García-Rodríguez Olaya; García-Fernández Gloria; Sánchez-Hervás Emilio; Fernandez-Hermida José R.; Higgins Stephen T. 《Canadian Metallurgical Quarterly》2011,25(1):174
The aims of this study were to assess the effectiveness of the Community Reinforcement Approach (CRA) plus vouchers treatment in a cohort of Spanish cocaine-dependent outpatients, and to examine the maintenance of treatment effects after the voucher intervention was discontinued. Sixty-four adult outpatients were randomly assigned to one of two treatment conditions, CRA plus vouchers or standard care. The vouchers program was implemented from weeks 1 to 24. Among patients assigned to the CRA plus vouchers condition, 65.5% completed 12 months of treatment versus 28.6% of those assigned to the standard care condition (p = .003). At the 12-month assessment, 58.6% of patients assigned to the CRA plus vouchers condition were abstinent, compared with 25.7% in the standard care condition (p = .008); furthermore, 34.5% of patients assigned to the CRA plus vouchers condition achieved twelve months of continuous cocaine abstinence, versus 17.1% in the standard care condition. Those treated in the CRA plus vouchers condition also achieved greater improvements in psychosocial functioning than those treated in the standard care condition. Overall, these results reveal an extension of the effectiveness of the CRA plus vouchers treatment to a community sample of cocaine-dependent outpatients, while also supporting the maintenance of treatment effects for 6 months after completion of the voucher program. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
673.
C. Andrés Méndez Paul Summers Gloria Menegaz 《International journal of imaging systems and technology》2015,25(1):56-67
It has been shown that the combination of multimodal magnetic resonance imaging (MRI) images can improve the discrimination of diseased tissue. The fusion of dissimilar imaging data for classification and segmentation purposes, however, is not a trivial task, as there is an inherent difference in information domains, dimensionality, and scales. This work proposed a multiview consensus clustering methodology for the integration of multimodal MR images into a unified segmentation aiming at heterogeneity assessment in tumoral lesions. Using a variety of metrics and distance functions this multiview imaging approach calculated multiple vectorial dissimilarity‐spaces for each MRI modality and it maked use of cluster ensembles to combine a set of unsupervised base segmentations into an unified partition of the voxel‐based data. The methodology was demonstrated with simulated data in application to dynamic contrast enhanced MRI and diffusion tensor imaging MR, for which a manifold learning step was implemented in order to account for the geometric constrains of the high dimensional diffusion information. © 2015 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 25, 56–67, 2015 相似文献
674.
675.
M. Pilar Cano Begoña de Ancos Gloria Lobo Marianne Monreal 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1996,202(4):279-284
An HPLC study of the carotenoid composition of fresh, frozen and canned papaya fruit slices was done. There were no qualitative differences between the carotenoid patterns of fresh and frozen papaya fruit slices (cultivar Sunrise). The major carotenoids found in papaya extracts were lycopene and carotenol fatty acid esters of-cryptoxanthin and-cryptoxanthin-5, 6-epoxide. Other xanthophylls detected were-crypto-xanthin,trans-zeaxanthin and cryptoflavin. It was possible to determine the quantitative losses of carotenoids in papaya slices as a result of the freezing process and frozen storage, since samples of these fruits were available before processing. The pigment pattern of the canned product showed lycopene as being a major pigment. Thermal treatment induced the degradation of carotenol fatty acid esters of xanthophylls. The freezing and canning processing of papaya slices led to significant decreases in the total carotenoids quantified by HPLC, with frozen female slices and canned samples showing lower amounts of pigments. Hunter colour values of frozen slices were similar to those of fresh papaya fruit slices. 相似文献
676.
M. Gloria Lobo M. P. Cano 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1998,206(5):343-349
The physical, physico-chemical and sensorial changes that occur during the freezing and frozen storage of hermaphrodite and
female papaya slices (Carica papaya L., cv Sunrise, Solo group) were studied. Samples were evaluated by panellists throughout a 1-year period of storage at –24°C;
the panellists described the fruit in terms of physico-chemical measurements of texture (firnmess and total pectins content),
colour [L, a
L
, b
L
, peroxidase (POD) and polyphenoloxidase (PPO) activities] and flavour/taste [soluble solids content, pH, tritatable acidity
and quality index (oBrix/acidity)], and ranked them in order of preference. Desserts prepared from frozen slices of hermaphrodite and female papaya
fruits mixed with orange, lemon and sugar were also evaluated. The freezing process itself did not result in significant changes
in the more commonly assessed quality parameters of texture, colour and flavour/taste. However, during storage at –24°C, changes
in sensorial characteristics occurred that became more evident as storage continued (≤ 9 months). Nevertheless, these quality
changes can be masked by using these papaya slices as an ingredient in fruit products, with frozen female papaya slices being
especially suitable for this purpose.
Received: 1 August 1997 / Revised version: 14 November 1997 相似文献
677.
Jean-Charles Leblanc Thierry Guérin Laurent No?l Gloria Calamassi-Tran Jean-Luc Volatier Philippe Verger 《Food Additives & Contaminants》2005,22(7):624-641
To estimate the dietary exposure of the main minerals and trace elements from retail food typically consumed by the French population, samples were purchased and then prepared and cooked prior to analysis. A total of 1080 individual food composites samples were collected and analysed for 18 elements (arsenic, lead, cadmium, aluminium, mercury, antimony, chrome, calcium, manganese, magnesium, nickel, copper, zinc, lithium, sodium, molybdenum, cobalt and selenium). Intakes were calculated from different food consumption patterns found in France for average and high consumers among adults and children. Dietary exposures of those consumers estimated from the France 2000 Total Diet Study (FTDS) are reported, and compared with existing nutritional reference values (Lowest threshold Intake, LTI) or toxicological reference values (Provisional Tolerable Weekly Intake, PTWI or Upper Level, UL) of the respective element and from previous French studies. This study confirms for the populations concerned, the low probability of nutritional or health risks due to food consumption. 相似文献
678.
679.
Daniel Barrera‐Arellano Victoria Ruiz‐Mndez Joaquín Velasco Gloria Mrquez‐Ruiz Carmen Dobarganes 《Journal of the science of food and agriculture》2002,82(14):1696-1702
Samples of oils of different degrees of unsaturation, namely palm olein, olive oil, high‐linoleic sunflower oil, high‐oleic sunflower oil, rapeseed oil and soybean oil, were heated at 180 °C for 2, 4, 6, 8 and 10 h in the presence or absence of their natural antioxidants. Also, tocopherol‐stripped oils were supplemented with α‐tocopherol (500 mg kg?1), δ‐tocopherol (500 mg kg?1) or a mixture of α‐, β‐, γ‐ and δ‐tocopherols (250 mg kg?1 each) and heated under the same conditions. Losses of tocopherols and formation of polymeric triacylglycerols were followed. Total polar compounds were also evaluated after 10 h of heating. Results demonstrated that tocopherols were lost very rapidly, in the expected order, with α‐tocopherol being the least stable. Polymeric and polar compound formation during heating was inhibited to a variable extent, being more dependent on the natural content and type of tocopherols than on the degree of unsaturation of the oil. For example, polymeric and polar compound contents in soybean oil were significantly lower than those found in high‐linoleic sunflower oil. However, the expected influence of the degree of unsaturation was evident when oils were unprotected or possessed identical initial antioxidant contents. Finally, levels of degradation compounds after 10 h of heating were not dependent on the remaining content of antioxidants. © 2002 Society of Chemical Industry 相似文献
680.
Belén Suárez Ángel L. Álvarez Yolanda Diñeiro García Gloria del Barrio Anna Picinelli Lobo Francisco Parra 《Food chemistry》2010
Methanolic and acetonic extracts of apple pomace were evaluated for phenolic profiles, antioxidant properties and antiviral effect against herpes simplex virus type 1 (HSV-1) and 2 (HSV-2). Acetone extraction yielded the higher amounts of phenolic compounds. The extraction method influenced the phenolic composition although antioxidant activity correlated weakly with phenols concentration. Among the polyphenols analysed, quercetin glycosides were the most important family, followed by dihydrochalcones. Apple pomace extracts were able to inhibit both HSV-1 and HSV-2 replication in Vero cells by more than 50%, at non-cytotoxic concentrations. Selectivity indexes (SI) ranged from 9.5 to 12.2. 相似文献