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World journal of gastroenterology 2007年第35期13卷 4737-4745页

作者： Deepak Darshan gregory j Anderson Iron Metabolism Laboratory The Queensland Institute of Medical ResearchBrisbaneAustralia

The human body requires about 1-2 mg of iron per day for its normal functioning, and dietary iron is the only source for this essential metal. Since humans do not possess a mechanism for the active excretion of iron, the amount of iron in the body is determined by the amount absorbed across the proximal small intestine and, consequently, intestinal iron absorption is a highly regulated process. In recent years, the liver has emerged as a central regulator of both iron absorption and iron release from other tissues. It achieves this by secreting a peptide hormone called hepcidin that acts on the small intestinal epithelium and other cells to limit iron delivery to the plasma. Hepcidin itself is regulated in response to various systemic stimuli including variations in body iron stores, the rate of erythropoiesis, inflammation and hypoxia, the same stimuli that have been known for many years to modulate iron absorption. This review will summarize recent findings on the role played by the liver and hepcidin in the regulation of body iron absorption.

关键词： Iron Homeostasis Intestinal iron absorption Liver Hepcidin

Moderate deviations from the hydrodynamic limit of the symmetric exclusion process

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Science China Mathematics 2003年第5期46卷 577-592页

作者：高付清 j.Quastel School of Mathematics and Statistics Wuhan University Wuhan 430072 China Departments of Mathematics and Statistics University of Toronto Toronto ON M5S 3G3 Canada

We investigate the moderate deviations from the hydrodynamic limit of the empirical density ofparticles and obtain a moderate deviation principle for a symmetric exclusion process.

关键词： exclusion process, hydrodynamic limit, large deviations, moderate deviations.

Bile-acid-induced cell injury and protection

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World journal of gastroenterology 2009年第14期15卷 1677-1689页

作者： Maria j perez Oscar Briz Research Unit University Hospital of Salamanca Laboratory of Experimental Hepatology and Drug Targeting CIBERehd University of Salamanca E.D. 129 37007 Salamanca Spain

Several studies have characterized the cellular and molecular mechanisms of hepatocyte injury caused by the retention of hydrophobic bile acids （BAs） in cholestatic diseases. BAs may disrupt cell membranes through their detergent action on lipid components and can promote the generation of reactive oxygen species that, in turn, oxidatively modify lipids, proteins, and nucleic acids, and eventually cause hepatocyte necrosis and apoptosis. Several pathways are involved in triggering hepatocyte apoptosis. Toxic BAs can activate hepatocyte death receptors directly and induce oxidative damage, thereby causing mitochondrial dysfunction, and induce endoplasmic reticulum stress. When these compounds are taken up and accumulate inside biliary cells, they can also cause apoptosis. Regarding extrahepatic tissues, the accumulation of BAs in the systemic circulation may contribute to endothelial injury in the kidney and lungs. In gastrointestinal cells, BAs may behave as cancer promoters through an indirect mechanism involving oxidative stress and DNA damage, as well as acting as selection agents for apoptosis-resistant cells. The accumulation of BAs may have also deleterious effects on placental and fetal cells. However, other BAs, such as ursodeoxycholic acid, have been shown to modulate BA-induced injury in hepatocytes. The major beneficial effects of treatment with ursodeoxycholic acid are protection against cytotoxicity due to more toxic BAs; the stimulation of hepatobiliary secretion; antioxidant activity, due in part to an enhancement in glutathione levels; and the inhibition of liver cell apoptosis. Other natural BAs or their derivatives, such as cholyI-N- methylglycine or pharmacological properties. cholylsarcosine, interest owing have also aroused to their protective

关键词： Apoptosis Cholestasis Liver Necrosis Oxidative stress Ursodeoxycholic acid

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《频率与语言结构的显现》述评

当代语言学 2004年第2期6卷 175-179页

作者： j.Bybee p.Hopper 程丽霞 361005 福建厦门厦门大学外文学院博士生信箱

(Frequency and the Emergence of Linguistic Structure)是joan Bybee和paul Hopper合编的一本论文集,由john Benjamins出版公司于2001年出版.

关键词：《频率与语言结构的显现》述评语言使用频率声学语音学语用型式词形变化词频效应语法

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美洲各国的音乐及其历史的叙述(下)

中央音乐学院学报 2011年第3期 119-121页

作者： j.p.伯克霍尔德蔡良玉

其他一些流行形式也不断从美洲各国传到了欧洲。墨面剧是从美国输出到欧洲的最早音乐形式。它是从1836年曼“爸爸”赖斯（T.“Daddy”Rice，译者按：他享有“墨面斟之父”之称）的独唱表演帮1843年弗吉尼亚墨面剧团的表演开始，由一拨... 详细信息

其他一些流行形式也不断从美洲各国传到了欧洲。墨面剧是从美国输出到欧洲的最早音乐形式。它是从1836年曼“爸爸”赖斯（T.“Daddy”Rice，译者按：他享有“墨面斟之父”之称）的独唱表演帮1843年弗吉尼亚墨面剧团的表演开始，由一拨又一拨来自美国的巡演者带到英格兰各岛的。

关键词：音乐形式美洲叙述历史弗吉尼亚英格兰欧洲美国

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纽约3号大街53号街办公楼,美国

世界建筑 1990年第4期 40-41页

作者： p.johnson and j.Burgee,Architeets 约翰逊与布吉事务所

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壳模型的综述

核物理动态 1991年第4期8卷 17-21,13页

作者： j.p.Elliott 赵玉民

本文首先对壳模型历史上几个重要进展做一简单回顾,随后讨论发展的目标,对诸如有效相互作用的选择以及入侵态的存在予以更详细的讨论。最后展望一下将来简化大规模壳模型计算的可能途径。

关键词：壳模型核结构

Characteristic analysis of CO_2 switching arcs under a DC current

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plasma Science and Technology 2018年第8期20卷 42-49页

作者： Xiaoling ZHAO j D YAN Dengming XIAO Department of Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200030People＇s Republic of China Department of Electrical Engineering and Electronics University of LiverpoolBrownlow HillLiverpool L69 3GJUnited Kingdom

The current interruption capability of a gas, when used in high voltage gas-blast circuit breakers,depends not only on its material properties but also the flow field since turbulence plays a dominant role in arc cooling during the interruption process. Based on available experimental results, a study of CO2 switching arcs under a DC（direct current） current in the model circuit breaker has been conducted to calibrate CO2 arc model and to analyse its electric and thermal property. Through detailed analysis of the results mechanisms responsible for the temperature distribution are identified and the domain energy transportation process of different region discussed. The present work provides significant coefficients for CO2 switching arc simulation and gives a better understanding of CO2 arc burning mechanisms.

关键词： energy transportation thermal and electric property CO2 switching arc

All-optical regeneration of polarization of a 40 gbit/s return-to-zero telecommunication signal[Invited]

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photonics Research 2013年第3期1卷 115-123页

作者： j.Fatome D.Sugny S.pitois p.Morin M.guasoni A.picozzi H.R.jauslin C.Finot g.Millot S.Wabnitz Laboratoire Interdisciplinaire Carnot de Bourgogne(ICB) UMR 6303 CNRS/Universitéde BourgogneDijonFrance Department of Information Engineering Universitàdi BresciaBresciaItaly

We report all-optical regeneration of the state of polarization of a 40 gbit∕s return-to-zero telecommunication sig*** device discussed here consists of a 6.2-km-long nonzero dispersion-shifted fiber,with low polarization mode dispersion,pumped from the output end by a backward propagating wave coming from either an external continuous source or a reflection of the *** initially scrambled signal acquires a degree of polarization close to 100%toward the polarization generator ***-optical regeneration is confirmed by means of polarization and bit-error-rate measurements as well as real-time observation of the eye *** show that the physical mechanism underlying the observed four-wave-mixing-based polarization attraction phenomenon can be described in terms of the geometric approach developed for the study of Hamiltonian singularities.

关键词： polarization communication signal