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排序方式: 共有513条查询结果,搜索用时 15 毫秒
51.
Taisa Venäläinen Ursula Schwab Jyrki Ågren Vanessa de Mello Virpi Lindi Aino-Maija Eloranta Sanna Kiiskinen David Laaksonen Timo A. Lakka 《Lipids》2014,49(5):467-479
Plasma fatty acid (FA) composition is known to be an indicator of dietary fat quality, but the associations of other dietary factors with plasma FA composition remain unknown in children. We investigated the cross-sectional associations of food consumption with the proportions of FA and estimated desaturase activities in plasma cholesteryl esters (CE) and phospholipids (PL) among children. The subjects were a population sample of 423 children aged 6–8 years examined at baseline of The Physical Activity and Nutrition in Children (PANIC) Study. We assessed food consumption by food records and plasma FA composition by gas chromatography. We used linear regression models adjusted for age, sex, physical activity and total energy intake to analyze the associations. A higher consumption of vegetable oil-based margarine (fat 60–80 %) was associated with a higher proportion of linoleic and α-linolenic acids in plasma CE and PL. A higher consumption of high-fiber grain products was related to a lower proportion of oleic acid in CE and PL. The consumption of candy was directly associated with the proportion of palmitoleic and oleic acid in plasma CE. The consumption of vegetable oil-based margarine was inversely associated with estimated stearoyl-CoA-desaturase activity in plasma CE and PL and the consumption of candy was directly related to it in plasma CE. The results of our study suggest that plasma FA composition is not only a biomarker for dietary fat quality but also reflects the consumption of high-fiber grain products and foods high in sugar among children. 相似文献
52.
Dr. Francesco A. Greco Dr. Elisa Albini Dr. Alice Coletti Dr. Daniela Dolciami Prof. Andrea Carotti Dr. Ciriana Orabona Prof. Ursula Grohmann Prof. Antonio Macchiarulo 《ChemMedChem》2019,14(24):2084-2092
Indoleamine 2,3-dioxygenase 1 (IDO1) catalyzes the oxidative cleavage of l -Tryptophan (l -Trp) to yield N-formyl-kynurenine in the first and rate limiting step of the kynurenine pathway. Bioactive metabolites, involved in the regulation of important immunological responses and neurological processes, are then produced by downstream enzymes along the pathway. Inhibitors of IDO1 are being designed and developed as therapeutic agents for immuno-oncology. In this work, we investigated the molecular recognition path of l -Trp to IDO1, integrating biophysical methods with supervised molecular dynamics (suMD) and mutagenesis experiments. Results allowed disclosing for the first time high and low dissociation constants of l -Trp to IDO1, and the presence of a metastable interaction site located at the upper part of a channel whose borders are defined by the EF-loop and the C-terminal part of the JK-loop. Collectively, our results provide new clues for the design of next-generation IDO1 ligands. 相似文献
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54.
Ursula Bentrup Jörg Radnik Udo Armbruster Andreas Martin Jork Leiterer Franziska Emmerling Angelika Brückner 《Topics in Catalysis》2009,52(10):1350-1359
A new setup is presented which enables simultaneous wide- and small-angle X-ray scattering (WAXS/SAXS) and Raman spectroscopic
experiments during the synthesis of Mo-based mixed oxide catalyst precursors at the μ-spot beamline at the Berliner Elektronenspeicherring-Gesellschaft
für Synchrotronstrahlung (BESSY). Furthermore, we report about the separate monitoring of the same reactions under comparable
conditions by simultaneous combined ATR/UV–vis/Raman spectroscopic measurements. For testing the performance of both experimental
setups two syntheses were described comprising the precipitation of metal molybdates by mixing solutions of metal nitrates
and ammonium heptamolybdate. Additionally, the effect of H3PO4 admixture on precipitation was investigated. The combined evaluation of spectroscopic and WAXS/SAXS data allows the discrimination
between different molybdate species appearing in solution and precipitate. Furthermore, these molybdate species could be assigned
to separate phases of different crystallinity. 相似文献
55.
We prove that any simplification order over arbitrary terms is an extension of an order by weight, by considering a related monadic term algebra called the spine. We show that any total ground-stable simplification order on the spine lifts to an order on the full term algebra. Conversely, under certain restrictions, a simplification ordering on the term algebra defines a weight function on the spine, which in turn can be lifted to a weight order on the original ground terms which contains the original order. We investigate the Knuth–Bendix and polynomial orders in this light. We provide a general framework for ordering terms by counting embedded patterns, which gives rise to many new orderings. We examine the recursive path order in this context. 相似文献
56.
In the dieless drawing technology the drawing dies are replaced by a heating device, generally by an induction coil. Bars of different cross-sections, round or even rectangular, with varying dimensions along the length can be produced. By using a cooling box in connection with the heating device this deformation process may also be employed for a thermomechanical treatment of steels. The special cooling strategy with low cooling rates at high temperatures (during ferrite formation) and higher cooling rates at lower temperatures favours the formation of multiphase microstructures (ferrite - bainite/martensite) with a low yield strength but a strong work hardening effect. The experiments were carried out on rods with a diameter of 16 mm of a plain low carbon steel (0.1%C, 0.7%Mn). The specimens were locally heated up to the maximum temperature ?max that initiates the dieless drawing process, and subsequently cooled with different coolants. The change in yield strength and tensile strength and the corresponding change in the ratio of both could be achieved by variation of ?max and the cooling conditions. The multiphase microstructure with desired mechanical properties was produced at a strain of about more than 0.45 within the region of ?max ≈ 900–1000°C and a finale cooling rate of about 20 K/s. 相似文献
57.
58.
与其他历史悠久的城市一样,丹麦首都哥本哈根市是有序和随意的规划设计共同作用的结果,它不仅继承了城市的人文建筑遗产,还体现了城市有机发展的过程.本项目位于哥本哈根市中心,紧挨着斯特罗里耶步行街. 相似文献
59.
To date, more than 1.3 million service members have served in the Global War on Terrorism. These men and women and their families face a range of stressful situations and must navigate many important tasks after a deployment. This article outlines four of the tasks of reintegration: redefining roles, expectations, and division of labor; managing strong emotions; abandoning emotional constriction and creating intimacy in relationships; and creating shared meaning. For each task, potential challenges are discussed and suggestions for how psychologists can support families are described. In addition, potential red flags and indicators that more intensive services may be warranted are reviewed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
60.