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Prediction of Enthalpies of Fusion for Divalent Rare Earth Halides Based on Modeling by Artificial Neural Networks and Pattern Recognition

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International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 24-26页

作者： Yimin Sun Zhiyu Qiao Minghong He(Applied science School, university of science & Technology beijing, beijing 100083, china)(National Natural science Foundation of china, beijing 100083, china) Applied science School University of Science and Technology Beijing Beijing 100083 China National Natural science Foundation of china Beijing 100083 China

The artificial neural network (ANN) and the pattern recognition were applied to study the correlation of enthalpies of fusion for divalent rare earth halides with their microstructural parameters,such as ionic radius and electronegativity. The model,represented by a back-propagation netal network, was trained with a 12 set of published data for divalent rare earth halides and then was used to predict the unknown ones. Also the criterion equations were ptesented to determine the enthalpies of fuSion for divalent rare earth halides using pattern recognition in mis work. The results from the model in ANN and criterion equations are in very good agreement with reference data.

关键词： BP neural network pattern recognition enthalpy of fusion divalent rare earth halides microstructural parameters

Calculating Models of Mass Action Concentrations for Fe-P and Cr-P Melts and Optimization of Their Thermodynamic Parameters

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International Journal of Minerals,Metallurgy and Materials 1999年第3期13卷 174-177页

作者： Jian Zhang(Metallurgy School, university of science and Technology beijing, beijing 100083, china) Metallurgy School University of Science and Technology Beijing Beijing 100083 China

Based on the phase diagrams, reliable reference experimental data and the coexistence theory of metallic melts structure involving compound formation, calculating models of mass action concentrations for Fe-P and Cr-P melts have been formulated. At the same time, some of their thermodynamic parameters have been optimized. The calculated results not only agree well with the measuredvalues, but also obey the mass action law rigorously, this in turn shows that these models can reflect the structural characteristics of corresponding melts.

关键词： activity phase diagram coexistence theory mass action concentration

A Back Look on the Binary Phase Diagrams of Metals from the Mass Action Law and the Coexistence Theory of Metallic Melts

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Journal of university of science and Technology beijing 2001年第1期8卷 15-19页

作者： Jian Zhang Metallurgy School, university of science and Technology beijing, beijing 100083, china Univ Sci & Technol beijing Met Sch Beijing 100083 Peoples R China

According to the mass action law and the coexistence theory of metallic melts, the mass action concentrations of Cu-Mg, Bi-Tl and Ni-Al melts involving compound formation have been calculated. The calculated results show that, except the ultimate case of pure element, when two elements are present in the melts, all structural units (atoms and molecules) without exception will be present in the melts, i.e., their concentrations may change from great to small, but they will not vanish into nothing, and only under such conditions, the calculated results both agree with practice and obey the law of mass action. In view of that over considerable wide composition range, the activities of both elements of the three solid binary alloys mentioned above have been measured, this seems in contradiction with the present relevant phase diagrams, in which the structural units are determined by composition range, so the latter needs further investigation and consideration.

关键词： activity phase diagram the mass action law the coexistence theory

β2 Adrenergic receptor on T lymphocytes and its clinical implications

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Progress in Natural science:Materials International 2009年第1期19卷 17-23页

作者： Xuelai Fan a,Yuedan Wang b,a peking university,School of Pharmaceutical sciences,beijing 100083.china b peking university,School of Basic Medical sciences,beijing 100083.china [a]peking university School of Pharmaceutical Sciences Beijing 100083 China [b]Peking University School of Basic Medical Sciences Beijing 100083 China

Sustained complex cross-talk between the immune system and the nervous system plays a vital role in retaining homeostasis in a healthy *** of the central regulatory mechanisms involved is the existence and functions of β2-adrenergic receptors(β2AR) on T *** article reviews research progress made recently,including the expression of adrenergic receptors on T lymphocytes,the structure and intracellular pathways of β2AR,the activation of β2AR by either endogenous or exogenous agonists,and the effect of β2AR stimulation on T cells which alters T cell proliferation,differentiation,cytokine production and T-helper-mediated antibody ***,we discuss the roles of β2AR played in the pathogenesis and treatment of autoimmune diseases.

关键词： Neuroimmunology β2-adrenergic receptor T cell Autoimmune

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补体相关性肾病诊断和治疗专家共识

中华内科杂志 2024年第3期63卷 258-271页

作者：北京大学医学部肾脏病学系专家组赵明辉不详北京大学第一医院肾内科、北京大学肾脏病研究所北京100034

随着补体系统在各类肾脏疾病中的作用机制逐渐阐明,针对补体活化不同环节的药物相继出现,部分已应用于临床。但补体靶向治疗仍存在诸多问题。北京大学医学系补体相关性肾病诊断和治疗专家共识协作组在国内外肾脏疾病指南/共识的基础上,... 详细信息

随着补体系统在各类肾脏疾病中的作用机制逐渐阐明,针对补体活化不同环节的药物相继出现,部分已应用于临床。但补体靶向治疗仍存在诸多问题。北京大学医学系补体相关性肾病诊断和治疗专家共识协作组在国内外肾脏疾病指南/共识的基础上,结合最新证据制定了本共识,简述了补体相关性肾病的发病机制、诊断思路、补体靶向治疗与特殊致病微生物的疫苗免疫等方面的最新证据和建议,为补体相关性肾病的诊断和治疗提供参考。

关键词：补体相关性肾病诊断治疗补体抑制剂

Intermittent hypoxia attenuates ischemia/reperfusion induced apoptosis in cardiac myocytes via regulating Bcl-2/Bax expression

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Cell Research 2003年第5期13卷 385-391页

作者： JIAN WEN DONG, HAI FENG ZHU, WEI ZHONG ZHU, HAI LEI DING, TIE MIN MA, ZHAO NIAN ZHOU 1 Laboratory of Hypoxic Cardiovascular physiology, Shanghai Institutes for Biological sciences, Chinese Academy of sciences, Shanghai 200031, china.2 department of physiology and Pathophysiology, health science center peking university, beijing 100083.china 1Laboratory of Hypoxic Cardiovascular physiology Shanghai Institutes for Biological SciencesChinese Academy of Sciences Shanghai 200031 China. E-mail: znzhou@*** 1Laboratory of Hypoxic Cardiovascular physiology Shanghai Institutes for Biological SciencesChinese Academy of Sciences Shanghai 200031 China. E-mail: znzhou@*** 1Laboratory of Hypoxic Cardiovascular physiology Shanghai Institutes for Biological SciencesChinese Academy of Sciences Shanghai 200031 China. E-mail: znzhou@*** 1Laboratory of Hypoxic Cardiovascular physiology Shanghai Institutes for Biological SciencesChinese Academy of Sciences Shanghai 200031 China. E-mail: znzhou@*** 1Laboratory of Hypoxic Cardiovascular physiology Shanghai Institutes for Biological SciencesChinese Academy of Sciences Shanghai 200031 China. E-mail: znzhou@*** 1Laboratory of Hypoxic Cardiovascular physiology Shanghai Institutes for Biological SciencesChinese Academy of Sciences Shanghai 200031 China. E-mail: znzhou@***

Intermittent hypoxia has been shown to provide myocardial protection against ishemia/reperfusion-induced injury. Cardiac myocyte loss through apoptosis has been reported in ischemia/reperfusion injury. Our aim was to investigate whether intermittent hypoxia could attenuate ischemia/reperfusion-induced apoptosis in cardiac myocytes and its potential mechanisms. Adult male Sprague-Dawley rats were exposed to hypoxia simulated 5000 m in a hypobaric chamber for 6 h/day, lasting 42 days. Normoxia group rats were kept under normoxic conditions. Isolated perfused hearts from both groups were subjected to 30 min of global ischemia followed by 60 min reperfusion. Incidence of apoptosis in cardiac myocytes was determined by terminal deoxynucleotidyl transferase mediated dUTP nick end labeling （TUNEL） and DNA agarose gel electrophoresis. Expressions of apoptosis related proteins, Bax and Bcl-2, in cytosolic and membrane fraction were detected by Western Blotting. After ischemia/reperfusion, enhanced recovery of ca

关键词： intermittent hypoxia apoptosis cardiac myocytes Bax Bcl-2.

2023 Guideline for the management of hypertension in the elderly population in china

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Journal of Geriatric Cardiology 2024年第6期21卷 589-630页

作者： Hypertension Branch of Chinese Geriatrics Society,beijing Hypertension Association,National Clinical Research center of the Geriatric Diseases Qi HUA Li FAN Zeng-Wu WANG Jing LI 不详 Xuanwu Hospital Capital Medical UniversityBeijingChina Chinese PLA General Hospital BeijingChina Fuwai Hospital Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

Preamble Hypertension is one of the most common chronic diseases and the primary risk factor for stroke,myocardial infarction and even cardiovascular *** than half of the elderly population has high blood *** people are a unique group,and strategies for the prevention,diagnosis,evaluation,and treatment of hypertension in elderly individuals differ significantly from those in the general population.

关键词： hypertension prevention diagnosis

Anti-tumor and immunoregulatory activities of Ganoderma lucidum and its possible mechanisms

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Acta Pharmacologica Sinica 2004年第11期 3-11页

作者： Zhi-bin LIN, Hui-na ZHANGdepartment of Pharmacology, School of Basic Medical sciences, peking university health science center, beijing 100083, china

Ganoderma lucidum (G lucidum) is a medicinal fungus with a variety of biological activities. It has long been used as a folk remedy for promotion of health and longevity in china and other oriental countries. The most attractive character of this kind of medicinal fungus is its immunomodulatory and anti-tumor activities. Large numbers of studies have shown that G lucidum modulate many components of the immune system such as the antigen-presenting cells, NK cells, T and B lymphocytes, The water extract and the polysaccharides fraction of G lucidum exhibited significant anti-tumor effect in several tumor-bearing animals mainly through its immunoenhancing activity. Recent studies also showed that the alcohol extract or the triterpene fraction of G lucidum possessed anti-tumor effect, which seemed to be related to the cytotoxic activity against tumor cells directly. Preliminary study indicated that antiangiogenic effect may be involved antitumor activity of G lucidum.

关键词： Ganoderma lucidum polysaccharides triterpene immunomodulatory activities anti-tumor activities

Existence of entire explosive positive radial solutions of sublinear elliptic systems

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Communications in Nonlinear science and Numerical Simulation 2001年第2期6卷 88-92页

作者： Zuodong YANG and Qishao LU department of Applied Mathematics, peking university of Aeronautics and Astronautics, beijing 100083, china department of Applied Mathematics Peking University of Aeronautics and Astronautics Beijing 100083 China

In this paper, our main purpose is to establish the existence of entire explosive positive radial solutions of quasilinear elliptic systems. The main results of the present paper are new and extend the previously know... 详细信息

关键词： quasilinear elliptic system entire explosive positive solution existence