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1.
In this study the combinatorial action of the main phenolic acids (ferulic, caffeic, p-coumaric and sinapic acids) found in extracts of free (ME) and bound phenolic acids (HE) from oat, barley and wheat flour on the modulation of NF-κB activity was investigated. The results show that combination of phenolic acids in low concentrations (<0.1 μg/ml) has a significant synergistic, or enhanced effect, on NF-κB activity, while their combination in high concentrations (0.3–70 μg/ml) helps to suppress the strong effect obtained by individual solutions of ferulic and p-coumaric acids. The modulation of NF-κB activity observed by HE extracts is the effect of combinatorial action of the phenolic acids present therein, while the modulation of NF-κB activity observed with ME extracts is the result of combinatorial action of phenolic acids together with other phenolic compounds present in the extracts. These results increase the knowledge about the health promoting effect from cereal consumption and dietary phenolic acids.  相似文献   
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Intake of fish and omega-3 (n-3) fatty acids is associated with a reduced concentration of plasma triacylglycerols (TAG) but the mechanisms are not fully clarified. Stearoyl-CoA desaturase-1 (SCD1) activity, governing TAG synthesis, is affected by n-3 fatty acids. Peripheral blood mononuclear cells (PBMC) display expression of genes involved in lipid metabolism. The aim of the present study was to estimate whether intake of lean and fatty fish would influence n-3 fatty acids composition in plasma phospholipids (PL), serum TAG, 18:1n-9/18:0 ratio in plasma PL, as well as PBMC gene expression of SCD1 and fatty acid synthase (FAS). Healthy males and females (n = 30), aged 20–40, consumed either 150 g of cod, salmon, or potato (control) daily for 15 days. During intervention docosahexaenoic acid (DHA, 22:6n-3) increased in the cod group (P < 0.05), while TAG concentration decreased (P < 0.05). In the salmon group both eicosapentaenoic acid (EPA, 20:5n-3) and DHA increased (P < 0.05) whereas TAG concentration and the 18:1n-9/18:0 ratio decreased (P < 0.05). Reduction of the 18:1n-9/18:0 ratio was associated with a corresponding lowering of TAG (P < 0.05) and an increase in EPA and DHA (P < 0.05). The mRNA levels of SCD1 and FAS in PBMC were not significantly altered after intake of cod or salmon when compared with the control group. In conclusion, both lean and fatty fish may lower TAG, possibly by reducing the 18:1n-9/18:0 ratio related to allosteric inhibition of SCD1 activity, rather than by influencing the synthesis of enzyme protein.  相似文献   
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Butter and other milk fat‐based products are valuable products for the dairy industry due to their unique taste, their textural characteristics, and nutritional value. However, an increased consumer demand for low‐fat‐based products increases the need for an increased essential understanding of the effective factors governing the structure of milk fat‐based products. Today, 2 manufacturing techniques are available: the churning method and the emulsification method. The first is typically used for production of butter with a globular structure, which has become increasingly popular to obtain low‐fat‐based products, typically without presence of milk fat globules. The microstructure of milk fat‐based products is strongly related to their structural rheology, hence applications. Structural behavior is not determined by one single parameter, but by the interactions between many. This complexity is reviewed here. Parameters such as thermal treatment of cream prior to butter making, water content, and chemical composition influence not only crystal polymorphism, but also the number and sizes of fat crystals. The number of crystal–crystal interactions formed within the products is related to product hardness. During storage, however, postcrystallization increases the solid fat content and strengthens the fat crystal network. The fat crystal network is strengthened by the formation of more and stronger crystal–crystal interactions due to mechanically interlinking of fat crystals, which occurs during crystal growth. Postcrystallization is directly linked to chemical composition. The initially observed microstructural difference causing different rheological behavior will disappear during storage due to postcrystallization and formation of more crystal–crystal interactions.  相似文献   
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Milk fat exists as globules in its natural state in milk. The potential of using globular fat to modulate the rheological properties and crystallization behavior in butter-like emulsions was studied in the present work. We conducted a comparative study of butter-like emulsions, with a fat phase consisting of 0, 10, 25, 50, or 100% anhydrous milk fat (AMF), the remaining fat being butter grains, and all samples containing 20% water, to obtain systematic variation in the ratio of globular fat. All emulsions were studied over 4 wk of storage at 5°C. By combining small and large deformation rheology, we conducted a detailed characterization of the rheological behavior of butter-like emulsions. We applied differential scanning calorimetry to monitor thermal behavior, confocal laser scanning microscopy for microstructural analysis, and low-field pulsed nuclear magnetic resonance spectrometry to measure solid fat content. By combining these techniques, we determined that increasing the fraction of globular fat (by mixing with butter grains) decreases the hardness of butter-like emulsions up to an order of magnitude at d 1. However, no difference was observed in thermal behavior as a function of butter grain content, as all emulsions containing butter grains revealed 2 endothermal peaks corresponding to the high (32.7°C ± 0.6) and medium (14.6°C ± 0.1) melting fractions of fatty acids. In terms of microstructure, decreasing the amount of butter grains in the emulsions resulted in formation of a denser fat crystal network, corresponding to increased hardness. Moreover, microstructural analysis revealed that the presence of butter grains resulted in faster formation of a continuous fat crystal network compared with the 100% AMF sample, which was dominated by crystal clusters surrounded by liquid oil. During storage, hardness remained stable and no changes in thermal behavior were observed, despite an increase in solid fat content of up to 5%. After 28 d of storage, we observed no difference in either microstructural or rheological properties, indicating that formation of primary bonds occurs primarily within the first day of storage. The rheological behavior of butter-like emulsions is not determined solely by hardness, but also by stiffness related to secondary bonds within the fat crystal network. The complex rheological behavior of milk fat-based emulsions is better characterized using multiple parameters.  相似文献   
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Stevens (1946) asserted that (a) consistency between the scale of measurement that generates a data set and the statistical/mathematical treatment that the data receive is necessary for interpretable results and (b) scale-analysis consistency is achievable by using techniques that are invariant with respect to admissible transformations. A number of individuals have argued for an alternative view that implies little or no relationship between scale of measurement and proper analytical techniques. These counterarguments are criticized. Stevens' original thesis is then reexamined in light of recent work on meaningfulness issues in measurement. The importance of measurement issues for an interpretable analysis is confirmed. However, the invariance criterion for selecting analytical techniques has severe problems, even though it is usually the only practicable criterion available. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Forty-three men between the ages of 18 and 48, in treatment for cocaine abuse or dependence, were evaluated for history of childhood attention-deficit hyperactivity disorder (ADHD) and adult symptoms (residual state). Participants completed a quantitative cocaine history and an interview designed to explore subjective cocaine experience. High ADHD scores were significantly correlated with high gram use of cocaine, r(41)?=?.37, p?r(41)?=?–.62, p?r(41)?=?.42, p?r(41)?=?.31, p?r(41)?=?.32, p?  相似文献   
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ABSTRACT: Defatted soybean flour contained 2820 parts per million (ppm) inorganic sulfate. The corresponding laboratory isolated soy proteins (ISP) contained 1364 ppm sulfate bound to a greater than 3000 molecular weight fraction. Defatted soy flour contained 0.98 nmoles of adenosine triphosphate (ATP) per 0.1 g. ATP levels decreased when the defatted flour was hydrated under a variety of conditions. Neither adenosine-5'-phosphosulfate or 3'-phosphoadenosine-5'-phosphosulfate could be detected in defatted soybean flour or in aqueous extracts of defatted flour. Defatted soy flour contained 1034 ppm reduced glutathione and 647 ppm reduced homogluatathione. These levels dropped to 62 and 13 ppm, respectively, immediately after the isoelectric precipitation step of ISP processing. No oxidized glutathione or homoglutathione were detected. Defatted flour contained 106 ppm cysteine-S-sulfonate, alkaline extracts of defatted flour contained 329 to 579 ppm and ISP contained 0 to 43 ppm. Neither sulfite nor methanethiol were detected until after the soluble components at pH 4.6 were separated from the precipitated soy proteins. These findings indicate that cysteine-S-sulfonate is present in defatted flour and increases during ISP processing. Also, the formation of sulfite during the final stages of ISP processing corresponds to elevated methanethiol levels.  相似文献   
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Reliability measures how well a system can be expected to perform its intended purpose; it is expressed as a probability function with time and environment as variables. This paper discusses the mechanics of component failure and repair and shows that power system behavior follows a Markov process. The reliability of simple system configurations is evaluated analytically by solving the Markov equations. The reliability of complex systems is more easily evaluated by the use of digital computer simulation. The simulation method is described.  相似文献   
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