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Total (non-fractionated) kernel proteins and the prolamin fraction (soluble in 75% ethanol) were extracted from oat (Avena sativa) var. Flämingstern kernel and from buckwheat (Fagopyrum esculentum) var. Kora kernel. As for buckwheat, extraction was effective only after kernel dehulling which allowed the removal of tannins and phenolic compounds that form complexes with proteins during extraction. The extracted proteins were analyzed using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE). Gels of the prolamin fractions of oat and buckwheat were used as reference gels in order to detect prolamins on gels of total kernel proteins. The occurrence of 26 and 29 spots corresponding to prolamins was found on gels of total oat proteins and on gels of total buckwheat proteins, respectively. The electrophoretic images of oat and buckwheat prolamins revealed organized subregions containing spots with similar isoelectric points (pI) and various molecular weights (MW), mostly on oat prolamin gels and spots of similar molecular weights with various isoelectric points, mostly on buckwheat prolamin gels. Such organized subregions can be used as identifiers for the occurrence of prolamin fractions in total proteins (particularly as regards buckwheat proteins).  相似文献   
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The effect of sonication time and kind of liquid medium on polyphenol retention and microstructure changes during predrying treatment of apple tissue was investigated. The apple cubes from ‘Idared’ cultivar were submerged in water or sucrose solution and sonicated indirectly in beakers placed in a water bath fitted with ultrasound transducers (25 kHz, 0.1 W/cm3) at 40 °C. The treatment was conducted with and without ultrasound applied for 45 and 90 min. The content of individual polyphenols was monitored by a reverse-phase high-performance liquid chromatography (RP-HPLC) method. The dominant phenolic compounds in apple were procyanidins, accounting for 56 % of total polyphenols. While a significant effect of sonication on mass transfer intensification was observed when the samples were dehydrated in sucrose solution, almost no negative effects of ultrasound application were perceived on polyphenols concentration, except for dimers of catechin. When using ultrasound in water solution, an increase in polyphenol compound losses was noted. Furthermore, the ultrasound energy caused an apple tissue structure modification which additionally affected polyphenol retention during predrying treatment.  相似文献   
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2-(4-Methoxyphenyl)ethylamine imprinted polymers were obtained from seven functional monomers in four porogens, and their properties were tested. Binding experiments revealed the highest selectivity towards a template for the polymer prepared from methacrylic acid in toluene (MIP1). The binding capacities and the imprinting factors were different for the stationary and the dynamic evaluation procedures. For MIP1, the binding capacities were 6.991 ± 0.081 or 18.247 ± 0.005 μmol g? 1, and the imprinting factors were 1.97 or 3.84, for stationary and dynamic procedures, respectively. The Scatchard analysis of MIP1 showed two classes of binding sites with values of the dissociation constants Kd equal to 16.2 and 192 μmol L? 1. Composition of polymers was supported by 13C CP/MAS NMR, FTIR and SEM-EDS analyses. The binding abilities of MIP1 towards the structurally related compounds showed that the ethylamine group together with steric effects governed the recognition mechanism. Finally, the high affinity of MIP1 towards dopamine or serotonin, but low towards norepinephrine and epinephrine was demonstrated.  相似文献   
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We developed and elaborated manufacturing conditions for the production of alginic acid fibers with high sorption properties. The fibers' tenacity obtained at a level of 16 cN/tex is suitable for textile processing these fibers, and will make it possible to produce a new generation of highly absorptive dressing materials. The presence of acid groups in the fiber‐forming material allows us to use them for the addition of new generation antibiotics, which makes it possible to extend the antibacterial effects of these fibers. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
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The influence of lipid peroxidation and heating duration on the amino acid pattern of wheat rolls was assessed in a model baking test. Therefore, three different types of dough were prepared including dough without any fat and two doughs with fat. To estimate the impact of lipid peroxidation products on the amino acid pattern, the two doughs containing fat were both made with rapeseed oil, one with fresh oil, the other with oxidised rapeseed oil. All kinds of dough were baked for three different duration times (18, 24 and 30 min). The lipid peroxidation status of both rapeseed oils was measured with the peroxide value and the p‐anisidine value of the unbaked fat. The amino acid content was analysed by HPLC after acid and alkaline hydrolysis. Besides determining water content and protein content, a sensory analysis was performed. Whereas the amino acid content in the dough without fat was only affected by the baking time, the doughs with rapeseed oil additionally showed a significant increase in amino acid degradation caused by lipid peroxidation products. Especially in the dough prepared with oxidised rapeseed oil, the amino acid content was partly decreased in raw dough without any heating influence. Confirming the influence of lipid peroxidation products in dough prepared with oxidised rapeseed oil, sensory analysis also showed the significantly worst overall score.  相似文献   
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The aim of our study was to estimate the surface expressions of CD95 (APO-1/Fas) antigen and the intracellular expressions of anti-apoptotic protein Bcl-2 and pro-apoptotic protein Bax in CD4(+)CD25(+)FoxP3(+) T regulatory lymphocytes (Tregs) as well as the percentage of CD8(+)CD28(+) T cytotoxic cells in peripheral blood of patients with pre-eclampsia in comparison with healthy pregnant women in the third trimester of physiological pregnancy. Twenty-four women with pre-eclampsia and 20 normal third trimester pregnant women were included in the study. The lymphocytes were isolated from peripheral blood samples and labeled with monoclonal antibodies. The expressions of surface antigens and intracellular proteins were estimated using flow cytometry. The population of CD4(+)CD25(+)FoxP3(+) Treg cells was significantly lower in peripheral blood of patients with pre-eclampsia when compared to normal third trimester pregnant women. The percentages of CD4(+)CD25(+)FoxP3(+) Treg cells that express Bcl-2 protein were significantly lower in peripheral blood of patients with pre-eclampsia when compared to healthy pregnant women, whereas the percentages of CD4(+)CD25(+)FoxP3(+) Treg cells with the expressions of Bax protein did not differ in both groups. Moreover, the mean fluorescence intensity (MFI) of Bcl-2 protein in CD4(+)CD25(+)FoxP3(+) Treg cells was significantly lower and MFI of Bax protein significantly higher in pre-eclampsia when compared to the control group. The percentage of CD8(+)CD28(+) T cells did not differ in both studied groups but MFI of CD28 antigen on T CD8(+) cells was significantly higher in pre-eclampsia when compared to the control group. The obtained results suggest that the deficit of CD4(+)CD25(+)FoxP3(+) Treg lymphocytes which is observed in pre-eclampsia may be associated with altered apoptosis signaling in Tregs.  相似文献   
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