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111.
Weanling rats were fed fat free diets supplemented with 10% added fatty acids so that dietary effects on bone marrow fatty acids could be determined. The addition or deletion of linoleic acid from the fatty acid supplement resulted in alterations of the fatty acid patterns of bone marrow lipids but to a lesser degree than in erythrocyte lipids. With myristic acid supplementation, increased amounts of stearic acid were found in the lipid fractions, the difference between the bone marrow and erythrocyte lipids being less marked than when linoleic acid was fed. The activities of the bone marrow lipases varied with the dietary treatment. When linoleic acid was fed, higher rates of hydrolysis were observed with saturated fatty acid substrates. The reverse occurred when saturated fatty acids were fed. 相似文献
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Multilayer films for food packaging applications composed of polyvinyl alcohol (PVOH) as the core layer and polyhydroxyalkanoate (PHA) as the outer skin layers were produced by the co‐extrusion process. Rheological properties of PVOH and PHA were performed and analyzed before co‐extruding into a cast film. Analysis of the rheological data indicated the processing temperatures and grades of the PVOH and PHA polymers that would produce similar viscosity and melt flow properties. To improve adhesion of the layers, PHA was grafted with maleic anhydride using a dicumyl peroxide initiator to provide a tie layer material, which improved the peel strength of the PHA and PVOH layers by over 2×. Oxygen transmission rate (OTR) testing showed that the multilayer sample provided an OTR of 27 cc/m2‐day at 0% relative humidity (RH) and rates of 41 and 52 cc/m2‐day at relative humidity values of 60% and 90% RH, respectively. This indicates significant barrier performance enhancement over monolayer PVOH that provided an OTR of 60 cc/m2‐day at 0% RH and 999 cc/m2‐day at 60% RH. Biodegradation testing of the films in the marine environment showed that both the unmodified and maleated PHA polymers displayed high levels of mineralization, whereas the PVOH material did not. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
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Sarah Laraichi Pilar Parra Rocío Zamanillo Ahmed El Amarti Andreu Palou Francisca Serra 《Lipids》2013,48(8):817-826
The scope of this study was to assess the impact of calcium and conjugated linoleic acid (CLA) supplementation on plasma fatty acid profiles and to evaluate potential synergistic effects of both compounds against dietary obesity. Mice separated into five experimental groups were followed: control (C), high-fat diet (HF), HF with calcium (Ca), HF plus CLA and HF with both Ca and CLA. Plasma metabolites and fatty acids were determined by commercial kits and gas chromatography, respectively. Both dietary calcium and CLA supplementation contributed to lower body fat gain under a HF diet. Maximum efficacy was seen with calcium; no additional effect was associated with the combined treatment with CLA. Plasma leptin, adiponectin and HOMA index were in accordance with an altered glucose/insulin homeostasis in the HF and HF + CLA groups, whereas control levels were attained under Ca-enriched diets. Plasma fatty acids showed minor changes associated to CLA treatment, but a high impact on PUFA was observed under Ca-enriched diets. Our results show that the mechanism underlying the anti-obesity effects of calcium supplementation is mediated mainly by changes in PUFA plasma profile. In addition, the lack of synergy on body weight reduction in combination with associated lipid profiles of calcium and CLA suggests that calcium may interfere with absorption and/or bioactivity of CLA, which can be of relevance when using CLA-fortified dairy products against human obesity. 相似文献
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Discovery of a Short‐Chain Dehydrogenase from Catharanthus roseus that Produces a New Monoterpene Indole Alkaloid 下载免费PDF全文
Dr. Anna K. Stavrinides Dr. Evangelos C. Tatsis Dr. Thu‐Thuy Dang Dr. Lorenzo Caputi Dr. Clare E. M. Stevenson Dr. David M. Lawson Dr. Bernd Schneider Prof. Sarah E. O'Connor 《Chembiochem : a European journal of chemical biology》2018,19(9):940-948
Plant monoterpene indole alkaloids, a large class of natural products, derive from the biosynthetic intermediate strictosidine aglycone. Strictosidine aglycone, which can exist as a variety of isomers, can be reduced to form numerous different structures. We have discovered a short‐chain alcohol dehydrogenase (SDR) from plant producers of monoterpene indole alkaloids (Catharanthus roseus and Rauvolfia serpentina) that reduce strictosidine aglycone and produce an alkaloid that does not correspond to any previously reported compound. Here we report the structural characterization of this product, which we have named vitrosamine, as well as the crystal structure of the SDR. This discovery highlights the structural versatility of the strictosidine aglycone biosynthetic intermediate and expands the range of enzymatic reactions that SDRs can catalyse. This discovery further highlights how a sequence‐based gene mining discovery approach in plants can reveal cryptic chemistry that would not be uncovered by classical natural product chemistry approaches. 相似文献
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Sarah Silva 《中国涂料》2021,(2):70-71
鉴于新冠肺炎疫情的持续流行,对于一年前潜在增长的保守估计需要做出大幅度的调整.第一次封锁解除后,欧洲粉末涂料市场出现了适度改善,但是,随着第二波的限制接踵而来,制造商对未来几个月的恢复预测至多持谨慎态度.
粉末涂料市场与许多市场一样,由于疫情的影响,短期预计会出现下降,但长期的预测是将会趋好.据市场研究公司IRL的Jo... 相似文献
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Reviews the book, Treating the juvenile offender edited by Robert D. Hoge, Nancy G. Guerra, and Paul Boxer (see record 2008-02979-000). This book rejuvenates interest in treatment for juvenile offenders, outlining the important advances that have been made, key challenges that remain, and useful principles for effectively meeting these challenges. Key themes that are emphasised include the importance of evidence-based approaches, interventions that are sensitive to the ecological systems within which youth are embedded, and rehabilitative strategies that are closely informed by research on youths’ risks, needs, and strengths. This book does not deliver a quick manual on how to deliver a particular program, but instead carefully models how to think about and approach treatment. While the book remains accessible to beginners, it is written in a manner which will be thought-provoking and informative even for experts. Furthermore, it is likely to have the positive effect of leaving readers with a desire to learn and do more to improve current practices. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献