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mSOD1转基因阳性家族性肌萎缩侧索硬化症模型大鼠的生物学特征

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中国组织工程研究与临床康复 2007年第46期11卷 9301-9304页

作者：包建玲黄红云刘彦王洪美王援朝刘佳曹敬丽方明俊北京市虹天济神经科学研究院北京市石景山区西山神经再生和功能重建研究所北京市100041

目的:家族性肌萎缩侧索硬化症转基因大鼠模型的鉴定及生物学特性的检测。方法:实验于2006-06/12在北京市虹天济神经科学研究院完成。从国外购来mSOD1转基因的肌萎缩侧索硬化症大鼠模型及其野生型进行繁殖扩增;PCR筛选mSOD1基因阳性鼠作... 详细信息

目的:家族性肌萎缩侧索硬化症转基因大鼠模型的鉴定及生物学特性的检测。方法:实验于2006-06/12在北京市虹天济神经科学研究院完成。从国外购来mSOD1转基因的肌萎缩侧索硬化症大鼠模型及其野生型进行繁殖扩增;PCR筛选mSOD1基因阳性鼠作为实验观察对象;观察其行为学变化、绘制生长曲线;记录神经传导速度及肌电情况;苏木精-伊红染色法观察股二头肌标本病理学变化;尼氏染色法进行中枢神经系统的神经元计数。实验过程中对动物的处置符合动物伦理学标准。结果:繁殖并扩增了肌萎缩侧索硬化症模型的种群;PCR法成功筛选出了mSOD1基因的阳性鼠,mSOD1阳性鼠在生长过程中逐渐出现四肢运动障碍、体质量急剧降低且很快死亡;发病鼠神经传导速度减慢、肌电显示出自发的纤颤电位;肌纤维发生萎缩;中枢神经系统的神经元丢失明显且有部分神经元发生空泡样变。结论:mSOD1转基因阳性的肌萎缩侧索硬化症模型大鼠可表现出与人类疾病的相似症状,生物学各项指标变化明显,是理想的肌萎缩侧索硬化症研究模型。

关键词：肌萎缩侧索硬化症超氧化物歧化酶1 转基因大鼠

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云南省马铃薯晚疫病菌对氟吗啉的敏感性测定

西南农业学报 2017年第3期30卷 580-583页

作者：曹继芬孙道旺张永妹杨明英赵志坚云南省农业科学院农业环境资源研究所云南昆明650205 云南省农业科学院生物技术与种质资源研究所云南昆明650223 迪庆州农业科学研究所云南香格里拉674400

采用含药平板法测定了分离自云南省马铃薯产区昭通、曲靖、大理、昆明和玉溪等地的晚疫病菌对新型杀菌剂氟吗啉的敏感性。结果表明:氟吗啉对云南省晚疫病菌的抑菌活性较高,50个菌株均为氟吗啉敏感菌株,EC_(50)值分布于0.0743~0.2934μg/... 详细信息

采用含药平板法测定了分离自云南省马铃薯产区昭通、曲靖、大理、昆明和玉溪等地的晚疫病菌对新型杀菌剂氟吗啉的敏感性。结果表明:氟吗啉对云南省晚疫病菌的抑菌活性较高,50个菌株均为氟吗啉敏感菌株,EC_(50)值分布于0.0743~0.2934μg/m L,平均EC_(50_值为(0.1638±0.0420)μg/m L,最不敏感菌株是最敏感菌株的3.95倍。分离自昭通的晚疫病菌菌株对氟吗啉最敏感,曲靖和大理的菌株次之,昆明和玉溪的菌株敏感性最低,但各地晚疫病菌对氟吗啉的EC50值无显著性差异。测定的马铃薯晚疫病菌对氟吗啉的敏感性频率分布呈连续的单峰曲线,可将平均EC_(50)值(0.1638±0.0420)μg/m L作为云南省马铃薯晚疫病菌对氟吗啉的敏感基线。氟吗啉与甲霜灵之间无交互抗性,氟吗啉可作为防控晚疫病的高效药剂。

关键词：晚疫病菌氟吗啉敏感基线马铃薯

Magnesium-L-threonate treats Alzheimer's disease by modulating the microbiota-gut-brain axis

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Neural Regeneration Research 2024年第10期19卷 2281-2289页

作者： Wang Liao Jiana Wei Chongxu Liu Haoyu Luo Yuting Ruan Yingren Mai Qun Yu Zhiyu cao Jiaxin Xu Dong Zheng Zonghai Sheng Xianju Zhou Jun Liu Department of Neurology The Second Affiliated Hospital of Guangzhou Medical UniversityGuangzhouGuangdong ProvinceChina Special Medical Service Center Neuroscience CenterIntegrated Hospital of Traditional Chinese MedicineSouthern Medical UniversityGuangdongGuangdong ProvinceChina Department of Rehabilitation The Second Affiliated HospitalGuangzhou Medical UniversityGuangzhouGuangdong ProvinceChina Department of Neurology Sun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Department of Neurology The Affiliated Brain Hospital of Guangzhou Medical UniversityGuangzhouGuangdong ProvinceChina Institute of Biomedical and Health Engineering Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong ProvinceChina

Disturbances in the microbiota-gut-brain axis may contribute to the development of Alzheimer's disease. Magnesium-L-threonate has recently been found to have protective effects on learning and memory in aged and Alzheimer's disease model mice. However, the effects of magnesium-L-threonate on the gut microbiota in Alzheimer's disease remain unknown. Previously, we reported that magnesium-L-threonate treatment improved cognition and reduced oxidative stress and inflammation in a double-transgenic line of Alzheimer's disease model mice expressing the amyloid-β precursor protein and mutant human presenilin 1(APP/PS1). Here, we performed 16S r RNA amplicon sequencing and liquid chromatography-mass spectrometry to analyze changes in the microbiome and serum metabolome following magnesium-Lthreonate exposure in a similar mouse model. Magnesium-L-threonate modulated the abundance of three genera in the gut microbiota, decreasing Allobaculum and increasing Bifidobacterium and Turicibacter. We also found that differential metabolites in the magnesiumL-threonate-regulated serum were enriched in various pathways associated with neurodegenerative diseases. The western blotting detection on intestinal tight junction proteins(zona occludens 1, occludin, and claudin-5) showed that magnesium-L-threonate repaired the intestinal barrier dysfunction of APP/PS1 mice. These findings suggest that magnesium-L-threonate may reduce the clinical manifestations of Alzheimer's disease through the microbiota-gut-brain axis in model mice, providing an experimental basis for the clinical treatment of Alzheimer's disease.

关键词： Alzheimer's disease APP/PS1 double-transgenic Alzheimer's disease mouse model inflammation intestinal barrier dysfunction magnesium-L-threonate microbiome microbiota-gut-brain axis oxidative stress serum metabolites

Mechanical Behaviour and Microstructure Evolution of Superplastic Mg-8.4 wt pct Li Alloy and Effect of Grain Size and Phase Ratio on Its Elongation

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Journal of Materials Science & Technology 2000年第1期16卷 55-58页

作者： cao, FR Cui, JZ Wen, jl Lei, F Northeastern Univ Sch Met & Mat Dept Mat & Forming Control Shenyang 110006 Peoples R China

Mechanical properties and microstructure evolution of Mg-8.4 wt pet Li alloy have been investigated. The superplastic elongation-to-failure 920% at 573 K and initial strain rate of 5 x 10(-4) s(-1) at low nominal stress 2 MPa has been demonstrated. It was shown through optical microstructure that the average grain sizes at gauge length section before and after superplastic tension and at grip section were 7.5 mu m, 31.7 mu m and 20 mu m respectively, indicating significant deformation induced grain growth and static grain growth. Comparison of experiment data with published data for superplastic Mg-Li alloys shows that fine grain size and about 50 to 50 phase ratio contribute to achieving the largest superplasticity. Some related research works in other alloys are compiled and further evidences to such theoretic argument are provided.

关键词： Magnesium alloys

国际投资协定的气候友好型改革:实践、目标与进路

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国际经济评论 2024年第5期 127-152,7,8页

作者：邓婷婷曹江琪张庆麟中南大学法学院广州商学院法学院

随着气候变化问题日益突出,国际投资协定(IAs)被锚定为跨领域、多主体协同治理气候变化的重要载体。近年来,为缓解传统IIAs与全球气候治理需求的矛盾与冲突,各国在条约实践中通过注重投资准入的气候友好型导向、限缩高碳投资者的受保护... 详细信息

随着气候变化问题日益突出,国际投资协定(IAs)被锚定为跨领域、多主体协同治理气候变化的重要载体。近年来,为缓解传统IIAs与全球气候治理需求的矛盾与冲突,各国在条约实践中通过注重投资准入的气候友好型导向、限缩高碳投资者的受保护空间、规定企业社会责任以及创设气候友好型投资的利好环境等多种措施对IAs进行了气候友好型改革的初步尝试。为了真正助推全球气候治理目标的实现,IIAs的改革需要体现人类命运共同体和可持续发展理念,在兼顾东道国与投资者公私利益的同时,构建东道国、投资者及其母国协同参与全球气候治理的责任共同体。基于现有实践,各国未来应当继续增强IAs气候友好型改革的系统性。具体而言,可以在明确气候友好型投资界定的基础上,强化例外条款中的气候因素。此外,还可以通过强化投资者气候保护义务、完善气候友好型投资激励规则和投资便利化规则以及减少投资者一国家争端解决机制对东道国实施气候措施的阻碍等方式,进一步推进IAs改革以应对气候治理面临的挑战。

关键词：国际投资协定气候变化气候友好型投资可持续发展

Characteristics of air quality in Tianjin during the Spring Festival period of 2015

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Atmospheric and Oceanic Science Letters 2016年第1期9卷 15-21页

作者： TANG Miao jl Dong-Sheng GAO Wen-Kang YU Zhong-Wang CHEN Kui cao Wan Tianjin Environment Monitoring Center Tianjin 300191China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100083China University of Chinese Academy of Sciences Beijing 100049China Tianjin Environmental Protection Bureau Tianjin 300191China

To better understand the characteristics of air quality and the relationship between the chemical composition evolution and source variation,an intensive atmospheric campaign was conducted in Tianjin,a megacity of the North China Plain,from 10 February to 6 March *** were 20 days exceeding the threshold value of secondary Chinese Ambient Air Quality Standards for PM2.5(75 μg m-3,daily average over 24 h)during the study *** air pollution episodes were selected for *** the pre-holiday pollution episode,NH^+_4,NO^-_3,and SO^(2-)_4 were more abundant,indicating that air pollution was caused by motor vehicle exhaust emissions and coal consumption under unfavorable meteorological *** Chinese Lunar New Year's Eve,widespread use of fireworks resulted in extremely high aerosol *** displays caused increases in K+ and also enrichment of SO^(2-)_4 relative to NO^-_*** holiday pollution episode was caused by regional transport,characterized by abundant SO^(2-)_4 and NH^+_*** addition,the aging processes of the particles from fireworks discharge played an important role in the formation of NO-3and SO^(2-)_*** Lantern Festival episode was characterized by a transition from the enrichment of K+ to secondary inorganic ions(NO^-_3,SO^(2-)_4,and NH^+_4).The results of this study are useful for a detailed understanding of the variation in atmospheric compositions and sources caused by anthropogenic activity,and highlight the importance of controlling intensive fireworks discharge.

关键词： tianjin water-soluble ions fireworks organic carbon elemental carbon

Comparative Analysis of Polysaccharides from Two Ecological Types of Leymus chinensis

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Chemical Research in Chinese Universities 2012年第4期28卷 677-681页

作者： LI Jing-jing BI Hong-tao YAN jl-hong SUN Fang FAN Sha-sha cao Gang ZHOU Yi-fa CHEN Xi-guang College of Marine Life Science Ocean University of China Qingdao 266003 P. R. China Key Laboratory of Adaptation and Evolution of Plateau Biota Northwest Institute of Plateau Biology Chinese Academy of Sciences Xining 810008 P. R. China Bee Research Institute Chinese Academy of Agricultural Sciences Beo'ing 100093 P. R. China School of Life Sciences Northeast Normal University Changchun 130024 P. R. China

Leymus chinensis（Trin.） Tzvel.,widely distributed at eastern Eurasian steppe and divided into gray-green type and yellow-green type,has different stress resistance to *** the present study,the water-soluble polysaccharides from two ecotypes of *** were analyzed in detail,and the differences between polysaccharides from the two ecotypes of *** in the yield,monosaccharide composition,molecular weight and structure were *** polysaccharides of *** were composed of both neutral and acidic *** neutral polysaccharides contained mannose,glucose,galactose,xylose and arabinose,and mainly consisted of β-1,4-Glcp,α-1,3-Galp and α-1,2-Xylp *** acidic polysaccharides contained mannose,rhamnose,glucuronic acid,galacturonic acid,glucose,galactose,xylose and ***,the yields,monosaccharides contents and the molecular weights of the polysaccharides from the two ecotypes of *** were ***,the resistance type（gray-green type） of *** contained a number of α-1,3-Manp and reducing end of β-Glcp residues,and much more O-methyl groups than normal type（yellow-green type） of *** differences of the polysaccharides of the two ecotypes of *** might be due to the long-term environmental adaptability of plant,and the differences of the polysaccharides might influence the stress resistance of ***.

关键词： Leymus chinensis Polysaccharide Fractionation

Optical Free-Induction Decay Effect in a Λ-Type Quantum-Beat Three-Level System

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Chinese Physics Letters 1997年第5期14卷 352-355页

作者： cao Zhuo-liang Department of Physics Anhui UniversityHefei 230039

With Bloch form,a coherent transient effect-optical free-induction decay is studied semiclassi-cally in theΛ-type three-level system driven by a coherent microwave *** decay behavior has three contributions:a homogeneous part with transverse relaxation time and two inhomo-geneous parts with different time constants that reflect the velocity bandwidth excited and the action of the driving microwave field.

关键词： field. decay coherent

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BFPC固定结合面虚拟材料热特性参数建模

辽宁工程技术大学学报（自然科学版） 2024年第1期43卷 62-67页

作者：于英华朱华杰曹泉沈佳兴阮文新辽宁工程技术大学机械工程学院辽宁阜新123000 珠海格力电器股份有限公司广东珠海519070

为确定含有玄武岩纤维树脂混凝土(basalt fiber polymer concrete,BFPC)固定结合面的机床基础件热特性参数,基于虚拟材料法建立了含有BFPC固定结合面组件的仿真模型,并对其热特性进行仿真分析;设计制造了含有BFPC固定结合面的组件,通过... 详细信息

为确定含有玄武岩纤维树脂混凝土(basalt fiber polymer concrete,BFPC)固定结合面的机床基础件热特性参数,基于虚拟材料法建立了含有BFPC固定结合面组件的仿真模型,并对其热特性进行仿真分析;设计制造了含有BFPC固定结合面的组件,通过实验方法研究组件的热特性。将仿真分析和实验研究的结果进行对比,分析表明:两种方法得到的组件在不同时刻的温度场具有一致性,且仿真与对应实验点温度的误差不大于8.57%,证明了所建立的BFPC固定结合面虚拟材料参数模型的准确性,以及基于此采用虚拟材料法对含有BFPC固定结合面组件进行热特性仿真分析的精确性和有效性。

关键词：玄武岩纤维树脂混凝土结合面热特性虚拟材料

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