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81.
Heating oilseeds has been shown to improve the milk fatty acid profile when given to dairy cows, compared to raw oilseeds. However, results from published studies are conflicting. The conditions of heating and storage of the oilseeds could be responsible for these differences, probably partly through their effects on lipid oxidation, the products of which could act on ruminal biohydrogenation (BH). Thus, 15 different treatments were applied to ground soybeans: three levels of heating (no heating, 30 min at 110 or 150°C) × 5 ambient storage durations (0, 1, 2, 4, or 6 months). Soybeans were incubated in vitro with ruminal fluid for 6 h. Triacylglycerol (TAG) polymers, hydroperoxides and hydroxyacids (HOA), aldehydes, and fatty acids were assayed in soybeans and ruminal culture. No TAG polymer was detected in any treatment. Soybeans stored for a long time had a high content of HOA, whereas those heated at 150°C, whatever the storage duration, had high aldehyde contents. The percentage disappearance of cis‐9,cis‐12 18:2 and cis‐9,cis‐12,cis‐15 18:3 in incubates decreased significantly in cultures with heated soybeans, especially at 150°C, suggesting that this partial protection of polyunsaturated fatty acids (PUFA) from BH was at least in part linked to the aldehyde content of the heated soybeans. Practical applications: Oilseeds given to ruminants are often heated, and heat treatment is known to generate oxidation products. Knowing what oxidation products influence ruminal biohydrogenation of unsaturated fatty acids could result in technological processes allowing a better transfer of unsaturated fatty acids from oilseeds to ruminant products.  相似文献   
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A series of 1‐arylsulfonyl‐5‐(N‐hydroxyacrylamide)indolines ( 7 – 15 ) has been developed; the compounds exhibited potent histone deacetylase (HDAC) inhibitory activities. Notably, almost all of this series exhibited better HDAC‐inhibitory and antiproliferative activities than 3‐(1‐benzenesulfonyl‐1H‐indol‐5‐yl)‐N‐hydroxyacrylamide ( 6 ), as reported in a previous study. Among these compounds, 3‐[1‐(4‐methoxybenzenesulfonyl)‐2,3‐dihydro‐1H‐indol‐5‐yl]‐N‐hydroxyacrylamide ( 9 ) showed a two‐ to tenfold increase in activity compared to SAHA ( 1 ) in the suppression of lipopolysaccharide‐induced cytokine production. Compound 9 also caused a marked reduction in carrageenan‐induced acute inflammation in a rat model. Taken together, these data indicated that 1‐arylsulfonyl‐5‐(N‐hydroxyacrylamide)indolines HDAC inhibitors exhibit potent anti‐inflammatory activity.  相似文献   
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A new monomer, methacryloyloxybis(benzenesulfonyl hydrazide) (MAOBSH) containing a foamable sulfonyl hydrazide functional group after decomposition by heating, was synthesized from 4,4′‐oxybis(benzenesulfonyl hydrazide) (OBSH) with methacryloyl chloride, and used to obtain poly(MAOBSH) as a polymeric foaming agent (PFA) in dry tetrahydrofuran at 70 °C using azobisisobutyronitrile as an initiator. The structures of the synthesized MAOBSH and poly(MAOBSH) were identified using Fourier transform infrared and 1 H NMR spectroscopies. The decomposition temperature of poly(MAOBSH) was determined to be 245 °C and this temperature was decreased to around 160 °C by adding an activator such as surface‐treated urea to the polymer. The exothermic temperature and heat determined by the decomposition of the polymer were 256 °C and 287 J g?1. The amount of gas evolution for poly(MAOBSH) measured at the decomposition temperature was 74 mL g?1. Furthermore, polymers incorporating the PFA showed better skin and finer cell structure as well as better mechanical properties such as elongation and compression set than polymers with added OBSH due to the better compatibility of the developed PFA with polymers. © 2012 Society of Chemical Industry  相似文献   
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Fibrous poly(1‐butene) membranes were prepared from solutions using mixed solvents via electrospinning. The electrospun fibrous poly(1‐butene) membranes were stretched at elongations of 8, 16 and 24%, respectively. Scanning electron microscopy and stress–strain analysis showed that the deformation was elastic at an elongation of 8%, while plastic deformation occurred above 16%. The crystalline transformation induced by mechanical stretching was investigated using wide‐angle X‐ray diffraction. The poly(1‐butene) membrane stretched at 24% exhibited decreased diffraction intensity at 2θ = 11.8° and 18.3°, corresponding to the (200) and (213) crystalline reflections, indicating that crystalline transformation from metastable form II to either stable form I or I′ occurred due to mechanical stretching. Copyright © 2011 Society of Chemical Industry  相似文献   
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