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31.
Albacore tuna (Thunnus alalunga) was steamed and canned in soy bean oil and sterilized at 115°C for 55 or 90 min. Proximate composition, total amino acid and available lysine content were determined during different phases of the process. Water and protein were lost in all phases and fat content increased. There was a decrease in available lysine during cooking but no loss in total amino acids. Nutritional evaluation of the protein showed differences in biological value and net protein utilization when the canned tuna was mixed with bread flour.  相似文献   
32.
Cell lines with high passage numbers exhibit alterations in cell morphology and functions. In the present work, C2C12 skeletal muscle cells with either low (<20) or high (>60) passage numbers (identified as lC2C12 or h-C2C12, respectively) were used to investigate the apoptotic response to H2 O2 as a function of culture age h-C2C12. We found that older cultures (h-C2C12 group) were depleted of mitochondrial DNA (mtDNA). When we analyzed the behavior of Bad, Bax, caspase-3 and mitochondrial transmembrane potential, we observed that cells in the h-C2C12 group were resistant to H2 O2 induction of apoptosis. We propose serially cultured C2C12 cells as a refractory model to H2 O2 -induced apoptosis. In addition, the data obtained in this work suggest that mtDNA is required for apoptotic cell death in skeletal muscle C2C12 cells.  相似文献   
33.
Stability of Lycopene Emulsions in Food Systems   总被引:2,自引:1,他引:2  
ABSTRACT The chemical stability of lycopene and the physical stability of lycopene emulsions diluted in 3 different food systems (skimmed milk, orange juice, and water as control) were studied. In these investigations, 3 different emulsifiers were used. It was found that lycopene stability strongly depends on the food system. In orange juice, lycopene is particularly stable. The emulsifiers used have only little influence on the stability of lycopene. Emulsions with α-tocopherol as an additional antioxidant showed a good lycopene stability in all food systems. Coalescence of oil droplets was not observed in any of the food systems investigated. Keywords: lycopene, stability, food systems  相似文献   
34.
Amaranth lectin from Amaranthus cruentus seeds was isolated, purified and partially characterized. The purification method used was based on its ability to interact with fetuin. Effects of temperature, pH and buffers and concentration were determined by measurement of lectin hemagglutination activity. Amaranth lectin biological activity was best maintained at temperatures between 4 and 30°C and pH's above or below 5. It was possible to store amaranth lectin at 4°C in acetate buffers, pH 4.8, for prolonged periods and to concentrate it 10-fold by ultrafiltration with only 18% loss of activity. A subunit molecular weight of 32,500 daltons was determined by SDS-PAGE for amaranth lectin.  相似文献   
35.
The rheological behavior of an aqueous solution composed of 65% sucrose and 0.1% CMC was experimentally determined from -10C to 50C using a rotational viscometer equipped with coaxial cylinders. The model solution behaved as pseudoplastic fluid, represented by the power-law model. Flow behavior and consistency indices determined at -10.1, 0.5, 9.8, 19.0, 30.1 and 50. OC, showed values between 0.79 to 0.86 and 0.15 to 10.22 Pa. sn, respectively. The effect of temperature on the rheological parameters was represented by Arrhenius-type relationships, with R2≥ 0.97. They were compared to the rheological behavior of a concentrated orange juice with 65° Brix and 7% pulp content. The comparison of separate rheograms for both fluids showed that the model solution can be used to represent concentrated orange juice.  相似文献   
36.
Pulsed‐Vacuum‐Osmotic‐Dehydration of kiwifruit (Actinidia chinensis) was studied using two kinds of osmotic solution: sucrose (65 Brix) and concentrated grape juice (63 Brix), three temperatures (25, 35 and 45C) and four vacuum pulse times (0, 5, 10 and 15 min). Experimental results enabled the mass transfer kinetics for water and solutes to be studied (compositional changes of the liquid fraction and changes in the liquid fraction/solid matrix ratio). The impregnation of samples, because of the vacuum pulse, was higher when concentrated grape juice was used as the osmotic solution, probably due to its lower viscosity. The effective diffusivity (De) was obtained for each experimental condition and the results show higher diffusivities for vacuum‐pulsed treatments, although differences between treatments with different vacuum‐pulse time could not be observed. De values were slightly greater for treatments with concentrated grape juice. The activation energies (Eo) were obtained by fitting the data to the Arrhenius equation.  相似文献   
37.
Detrimental immune response has a crucially important role in the development and progression of inflammatory eye diseases. Inflammatory mediators and proteolytic enzymes released by activated immune cells induce serious injury of corneal epithelial cells and retinal ganglion cell which may result in the vision loss. Mesenchymal stem cells (MSCs) are regulatory cells which produce various immunosuppressive factors that modulate phenotype and function of inflammatory immune cells. However, several safety issues, including undesired differentiation and emboli formation, limit clinical use of MSCs. MSC-derived exosomes (MSC-Exos) are nano-sized extracellular vesicles which contain all MSC-derived immunoregulatory factors. Intraocular administration of MSC-Exos efficiently attenuated eye inflammation and significantly improved visual acuity in experimental animals without causing any severe side effects. As cell-free product, MSC-Exos addressed all safety issues related to the transplantation of MSCs. Therefore, MSC-Exos could be considered as potentially new remedy for the treatment of inflammatory eye diseases which efficacy should be explored in up-coming clinical trials.  相似文献   
38.
In eighteenth-century France, François Cointeraux was as an advocate of pisé , a provincial technique that rammed pure earth into artificial stones. Economical and sturdy, pisé could be used for a variety of rural constructions, ranging from sheds to silos. To share this knowledge, Cointeraux founded the "School of Agritecture," which combined agriculture ("agri-") with architecture ("-tecture"), and taught students how to work the land for food and shelter. Despite its practical benefits, the hybrid curriculum was not adopted elsewhere, for its agrarian values ultimately proved incompatible with the interests of industrial capitalism.  相似文献   
39.
40.
ABSTRACT: Questions have been raised about the wisdom of low‐income homeownership policies for many reasons. One potential reason to be skeptical: low‐income homebuyers perhaps may be constrained to purchase homes in disadvantaged neighborhoods. This is a potential problem because home purchases in such neighborhoods: (1) may limit appreciation; (2) may reduce quality of life for adults; and (3) may militate against reputed advantages of homeownership for children. Our study examines the neighborhood conditions of a group of 126 low‐income homebuyers who purchased their first home with assistance from the Home Ownership Program (HOP) operated by the Denver Housing Authority. Our approach is distinguished by its use of a comprehensive set of objective and subjective indicators measuring the neighborhood quality of pre‐move and post‐move neighborhoods. Do low‐income homebuyers sacrifice neighborhood quality to buy their homes? Our results suggest that the answer to this question is more complex than it might at first appear. On the one hand, HOP homebuyers purchased in a wide variety of city and suburban neighborhoods. Nonetheless, a variety of neighborhood quality indicators suggest that these neighborhoods, on average, were indeed inferior to those of Denver homeowners overall and to those in the same ethnic group. However, our analyses also revealed that their post‐move neighborhoods were superior to the ones they lived in prior to homeownership. Moreover, very few HOP destination neighborhoods evinced severe physical, environmental, infrastructural, or socioeconomic problems, as measured by a wide variety of objective indicators or by the homebuyers' own perceptions. Indeed, only 10% of HOP homebuyers perceived that their new neighborhoods were worse than their prior ones, and only 8% held pessimistic expectations about their new neighborhoods' quality of life. Finally, we found that Black homebuyers fared less well than their Latino counterparts, on average, in both objective and subjective measures.  相似文献   
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