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我国土壤低硒带的气候成因研究

生物技术进展 2017年第5期7卷 387-394页

作者：孙国新李媛李刚陈正朱永官中国科学院生态环境研究中心城市与区域生态国家重点实验室北京100085 中国市政工程华北设计研究总院有限公司第四设计研究院天津300074 中国科学院城市环境研究所城市环境与健康重点实验室福建厦门361021 西交利物浦大学环境科学系江苏苏州215123

我国土壤硒含量分布严重不均,从东北到西南地区存在一条典型的土壤低硒带,然而该低硒带的成因至今仍不明确。基于硒干湿沉降和挥发的机理,亚洲季风造成的硒沉降和微生物驱动的硒挥发被认为是形成我国低硒带的主要驱动力。其中,夏季季风... 详细信息

我国土壤硒含量分布严重不均,从东北到西南地区存在一条典型的土壤低硒带,然而该低硒带的成因至今仍不明确。基于硒干湿沉降和挥发的机理,亚洲季风造成的硒沉降和微生物驱动的硒挥发被认为是形成我国低硒带的主要驱动力。其中,夏季季风引起的湿沉降是东南地区富硒的主要原因,而冬季季风引起的干沉降是西北地区富硒的主要原因。中部地区因为硒挥发与沉降量相当,土壤中硒净积累很少,形成了低硒带。而且在全球气候变化的影响下,我国土壤中的硒含量将会呈现下降的趋势。

关键词：土壤硒分布低硒带硒沉降硒挥发季风

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滦河沉积物层理构造的类型和组合

同济大学学报 1982年第2期 97-113页

作者：李从先陈刚王利张玉民石油部海洋石油勘探局研究院

根据滦河下游的野外调查,我们对十五种河流沉积构造作了描述,并对其形成过程作了探讨.在每个沉积旋回中,单个沉积构造只反映水动力的局部作用,垂直层序上沉积构造的组合才反映沉积期间的全部动力条件,因此,沉积构造组合是解释沉积环境... 详细信息

根据滦河下游的野外调查,我们对十五种河流沉积构造作了描述,并对其形成过程作了探讨.在每个沉积旋回中,单个沉积构造只反映水动力的局部作用,垂直层序上沉积构造的组合才反映沉积期间的全部动力条件,因此,沉积构造组合是解释沉积环境的关键。层理构造是沉积物中最常见、最易直接观察的现象,是沉积物固有的特征。层理构造是动力作用的直接产物,又异常灵敏地反映动力条件的变化,因此,研究沉积构造能为判别沉积环境提供重要依据。滦河下游地区有许多人工剖面和天然露头,较系统地揭示了河流沉积构造,为研究工作提供了有利条件.本文旨在分析滦河层理构造的类型和组合,以阐明其在判别沉积环境中的意义。

关键词：层理层系构造组合成层构造沉积构造地质构造滦河下游图版

Overexpression of low-density lipoprotein receptor prevents neurotoxic polarization of astrocytes via inhibiting NLRP3 inflammasome activation in experimental ischemic stroke

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Neural Regeneration Research 2025年第2期20卷 491-502页

作者： Shuai Feng Juanji li Tingting liu Shiqi Huang Xiangliang chen Shen liu Junshan Zhou Hongdong Zhao Ye Hong Department of Neurology Nanjing First HospitalNanjing Medical UniversityNanjingJiangsu ProvinceChina Department of Neurology Nanjing Jinling HospitalAffiliated Hospital of Medical SchoolNanjing UniversityNanjingJiangsu ProvinceChina

Neurotoxic astrocytes are a promising therapeutic target for the attenuation of cerebral ischemia/reperfusion ***-density lipoprotein receptor,a classic cholesterol regulatory receptor,has been found to inhibit NLR family pyrin domain containing protein 3(NLRP3)inflammasome activation in neurons following ischemic stroke and to suppress the activation of microglia and astrocytes in individuals with Alzheimer’s ***,little is known about the effects of low-density lipoprotein receptor on astrocytic activation in ischemic *** address this issue in the present study,we examined the mechanisms by which low-density lipoprotein receptor regulates astrocytic polarization in ischemic stroke ***,we examined low-density lipoprotein receptor expression in astrocytes via immunofluorescence staining and western blotting *** observed significant downregulation of low-density lipoprotein receptor following middle cerebral artery occlusion reperfusion and oxygen-glucose deprivation/***,we induced the astrocyte-specific overexpression of low-density lipoprotein receptor using astrocyte-specific adeno-associated ***-density lipoprotein receptor overexpression in astrocytes improved neurological outcomes in middle cerebral artery occlusion mice and reversed neurotoxic astrocytes to create a neuroprotective ***,we found that the overexpression of low-density lipoprotein receptor inhibited NLRP3 inflammasome activation in oxygen-glucose deprivation/reoxygenation injured astrocytes and that the addition of nigericin,an NLRP3 agonist,restored the neurotoxic astrocyte *** findings suggest that low-density lipoprotein receptor could inhibit the NLRP3-meidiated neurotoxic polarization of astrocytes and that increasing low-density lipoprotein receptor in astrocytes might represent a novel strategy for treating cerebral ischemic stroke.

关键词： inflammation ischemia/reperfusion injury ischemic stroke low-density lipoprotein receptor neuroprotective astrocytes neurotoxic astrocytes NLRP3 inflammasome polarization

达氏鲟gdf11基因cDNA的克隆及组织表达特征分析

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淡水渔业 2017年第1期47卷 30-34,41页

作者：杜浩冷小茜张书环叶欢沈丽刘志刚陈细华危起伟中国水产科学研究院长江水产研究所农业部淡水生物多样性保护重点实验室武汉430223

本研究克隆了达氏鲟(Acipenser dabryanus)生长转化因子gdf11(growth differentiation factor 11)基因cDNA。达氏鲟gdf11基因cDNA序列全长1 298 bp(不包括Poly A),开放阅读框为1 191 bp,编码396个氨基酸,5非编码区长19 bp;3非编码区长88 bp。通过Signal P软件预测含有N端21aa的信号肽。组织表达特征分析结果显示,gdf11在7种组织中均有表达,在眼和鳃中的表达量较高;不同水流条件下,鳃和心脏gdf11的表达量有显著性差异,静水中鳃gdf11表达量是流水(流速27.0±3.0 cm/s)的4.70倍,而心脏中的表达量是流水的2.72倍。这暗示了gdf11可能在呼吸代谢中发挥功能。

关键词：达氏鲟(Acipenser dabryanus) gdf11基因基因克隆组织表达特征

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环境规划在我国规划体系中的定位及转型

四川环境 2011年第5期30卷 71-74页

作者：李剑陈刚才重庆市环境保护局重庆401147

结合对我国的规划体系及其发展方向的分析,指出了目前环境规划忽视对国土空间进行谋划的问题,并对其转型方向提出了建议。主要结论:环境规划应当在继续履行好争取财政资金等社会资源功能的同时,增强对资源环境承载能力这一重要自然资源... 详细信息

结合对我国的规划体系及其发展方向的分析,指出了目前环境规划忽视对国土空间进行谋划的问题,并对其转型方向提出了建议。主要结论:环境规划应当在继续履行好争取财政资金等社会资源功能的同时,增强对资源环境承载能力这一重要自然资源的配置功能,转变为横跨国民经济和社会发展、国土空间开发管制两大领域的综合性规划;要加强环境保护空间管制的基础性研究,建立一套约束性环境规划指标体系,增强其权威性和可操作性,充分发挥规划的作用。

关键词：环境规划国土空间规划资源环境承载能力

猪传染性水疱病病毒(SVDV)在微细胞和微胞质体内的复制

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实验生物学报 1988年第1期 103-113页

作者：李维刚陈利华翟中和北京大学生物学系

本实验研究了SVDV在微细胞和微胞质体两种非完整细胞体系内的复制。用秋水仙素处理IB-RS-2细胞,在含有松胞素B的Ficoll 400不连续梯度中进行高速离心,制备了大量的微细胞。微细胞在正常的培养条件下60小时后仍有70%以上存活,用SVDV感染... 详细信息

本实验研究了SVDV在微细胞和微胞质体两种非完整细胞体系内的复制。用秋水仙素处理IB-RS-2细胞,在含有松胞素B的Ficoll 400不连续梯度中进行高速离心,制备了大量的微细胞。微细胞在正常的培养条件下60小时后仍有70%以上存活,用SVDV感染只需4—5小时就几乎全部脱落。并证明微细胞能繁殖出有感染力的子代病毒。用松胞素B去核技术制备的微胞质体,运用扫描电镜和显微放射自显影的方法证实了SVDV可以在微胞质体内复制病毒RNA,并引起微胞质体病变。同时纯化了用松胞素B处理悬浮的IB-RS-2细胞而制备的大量的微胞质体,SVDV感染后,可以产生一定数量的有感染力的子代病毒。虽然滴度低于完整细胞繁殖的病毒,但证明了SVDV可以利用微胞质体中少量的细胞成分和酶类完成其感染、复制和装配一系列繁殖过程,产生有感染力的子代病毒。

关键词： Microcell.Microcytoplast.Reproduction of virus.

Numerical study of three-dimensional developments of premixed flame induced by multiple shock waves

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Acta Mechanica Sinica 2018年第6期34卷 1035-1047页

作者： Xiao chen gang Dong Baoming li Key Laboratory of Transient Physics Nanjing University of Science and TechnologyNanjing 210094China

The three-dimensional interactions of a perturbed premixed flame interface with a planar incident shock wave and its reflected shock waves are numerically simulated by solving the compressible,reactive Navier-Stokes equations with the high-resolution scheme and a single-step chemical *** effects of the initial incident shock wave strength (Mach number) and the initial perturbation pattern of interface on the interactions are *** distinct properties of perturbation growth on the flame interface during the interactions are *** results show that perturbation growth is mainly attributed to the flame stretching and *** flame stretching is associated with the larger-scale vortical flow due to RichtmyerMeshkov instability while the flame propagation is due to the chemical *** mixing properties of unburned/burned gases on both sides of the flame are quantitatively analyzed by using integral and statistical *** results show that the large-scale flow due to the vortical motion always plays a dominating role during the reactive interaction process;however,the effect of chemistry becomes more important at the later stage of the interactions,especially for higher Mach number *** scalar dissipation due to the molecular diffusion is always small in the present study and can be negligible.

关键词： Flame interface instability Richtmyer-Meshkov instability Large-scale flow Chemical reaction Scalar dissipation

Active Control Law Design for Flutter/LCO Suppression Based on Reduced Order Model Method

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Chinese Journal of Aeronautics 2010年第6期23卷 639-646页

作者： chen gang li Yueming Yan Guirong MOE Key Laboratory for Strength&Vibration School of AerospaceXi’an Jiaotong UniversityXi’an710049China

Active stability augmentation system is an attractive and promising technology to suppress flutter and limit cycle oscillation (LCO). In order to design a good active control law, the control plant model with low order and high accuracy must be provided, which is one of the most important key points. The traditional model is based on low fidelity aerodynamics model such as panel method, which is unsuitable for transonic flight regime. The physics-based high fidelity tools, reduced order model (ROM) and CFD/CSD coupled aeroservoelastic solver are used to design the active control law. The Volterra/ROM is applied to constructing the low order state space model for the nonlinear unsteady aerodynamics and static output feedback method is used to active control law design. The detail of the new method is demonstrated by the Goland+ wing/store system. The simulation results show that the effectiveness of the designed active augmentation system, which can suppress the flutter and LCO successfully.

关键词： limit cycle oscillation aeroelasticity reduced order model active control law static output feedback

Prevalence of Helicobacter pylori infection in Chinese military personnel:A cross-sectional,multicenter-based study

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World Journal of Gastroenterology 2025年第3期31卷 42-49页

作者： Han-chen Min Chun-Yan Zhang Fang-Yu Wang Xiao-Hui Yu Shan-Hong Tang Hong-Wu Zhu Ya-gang Zhao Ji-Luo liu Jian Wang Jing-Han Guo Xiao-Mei Zhang Yun-Sheng Yang Chinese People’s liberation Army Medical School Chinese People’s Liberation Army General HospitalBeijing 100853China Department of Gastroenterology and Hepatology The First Medical CenterChinese People’s Liberation Army General HospitalBeijing 100853China Sixth Healthcare Department The Second Medical CenterChinese People’s Liberation Army General HospitalBeijing 100853China Department of Gastroenterology The 940th Hospital of Joint Logistic Support Force of Chinese People’s Liberation ArmyLanzhou 730050Gansu ProvinceChina Department of Gastroenterology General Hospital of Western Theater CommandChengdu 610011Sichuan ProvinceChina Department of Gastroenterology General Hospital of Southern Theater CommandGuangzhou 510010Guangdong ProvinceChina Department of Epidemiology Naval Medical UniversityShanghai 200433China School of Medicine Nankai UniversityTianjin 300071China National Clinical Research Center for Geriatric Diseases Chinese People’s Liberation Army General HospitalBeijing 100853China

BACKGROUND Helicobacter pylori(***)infection is a prevalent disease encountered in military internal medicine and recognized as the main cause of dyspepsia,gastritis,and peptic ulcer,which are common diseases in military *** guidelines in China state all patients with evidence of active infection with *** are offered ***,the prevalence of *** infection and its regional distribution in the military population remain unclear,which hinders effective prevention and treatment *** the prevalence of *** infection in the military population will aid in the development of customized strategies to better manage this infectious *** To investigate the prevalence of *** infection in the Chinese military population in different geographic *** This multicenter,retrospective study included 22421 individuals from five tertiary hospitals located in north,east,southwest,and northwest cities of *** infection was identified using the urea breath test,which had been performed between January 2020 and December *** Of the 22421 military service members,7416(33.1%)were urea breath *** highest prevalence of *** was in the 30-39 years age group for military personnel,with an infection rate of 34.9%.The majority of infected subjects were younger than 40-years-old,accounting for 70.4%of the infected *** individuals serviced in Lanzhou and chengdu showed a higher infection prevalence than those in Beijing,Nanjing,and Guangzhou,with prevalence rates of 44.3%,37.9%,29.0%,31.1%,and 32.3%,*** *** infection remains a common infectious disease among military personnel in China and has a relatively high prevalence rate in northwest China.

关键词： Helicobacter pylori Prevalence Military personnel Urea breath test Multicenter study