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Neural Regeneration Research 2012年第28期7卷 2199-2205页

作者： Jun Wang Jing Ge liu Yang Haiyan Zhang xuli Li Dan Xue Department of Gynaecology and Obstetrics General Hospital of Shenyang Military Region Shenyang 110016 Liaoning Province China Department of Gynaecology and Obstetrics the 202 Hospital of Chinese PLA Shenyang 110003 Liaoning Province China Shenyang Women and Children Health Center Shenyang 110014 Liaoning Province China

Hyperhomocysteinemia is an important risk factor for preeclampsia-eclampsia. This study established a pregnant rat model of hyperhomocysteinemia, in which blood plasma homocysteine concentrations were twice or three times greater than that of normal pregnant rats. TUNEL revealed an increase in the number of apoptotic cells in the frontal cortex of pregnant rats with hyperhomocysteinemia. In addition, immunohistochemical staining detected activated nuclear factor-KB-positve cells in the frontal cortex. Reverse transcription-PCR detected that mRNA expression of the anti-apoptotic gene bcl-2 diminished in the frontal cortex. In situ hybridization and western blotting revealed that N-methyi-D- aspartate receptor 1 mRNA and protein expression was upregulated in the frontal cortex and hippocampus. These results indicate that hyperhomocysteinemia can induce brain cell apoptosis, increase nerve excitability, and promote the occurrence of preeclampsia in pregnant rats.

关键词： hyperhomocysteinemia homocysteine preeclampsia frontal cortex N-methyI-D-aspartate receptor nerve excitability cell apoptosis pregnancy brain neural regeneration

A Correlative Study between CT Perfusion Parameters and Angiogenesis in Rabbit VX2 Liver Tumors

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Open Journal of Medical Imaging 2016年第3期6卷 72-79页

作者： Hao Xu xuli Min Kang liu Lin Yang Sichuan Key Laboratory of Medical Imaging Department of Radiology Affiliated Hospital of North Sichuan Medical College Nanchong China

Objective: The purpose of this study was to evaluate the correlation between CT perfusion parameters and the hypoxia-inducible factor-1 alpha (HIF-1α), vascular en-dothelial growth factor (VEGF), matrix metalloproteinase-2 (MMP-2) and microvessel density (MVD) marked by CD34 molecular of rabbit VX2 liver tumors and to investigate the value of CT perfusion imaging in evaluating tumor angiogenesis. Material and methods: Twenty-four cases of rabbit VX2 liver tumor were performed by CT perfusion scanning. Hepatic artery perfusion (HAP), portal vein perfusion (PVP), total hepatic blood flow (THBF) and hepatic perfusion index (HPI) were measured by perfusion software. HIF-1α, VEGF and MMP-2 expression and MVD were detected in the 24 rabbit VX2 liver tumor tissue samples using immunohistochemical method. The correlation between the HIF-1α, VEGF, MMP-2 expression and MVD and CT perfusion parameters were analyzed. Results: Correlation analysis revealed that the expression of HIF-1α, MMP-2, MVD were positively related to the HAP, THBF, HPI (p 0.05);and correlation analysis revealed that the expression of VEGF was positively related to the HAP, HPI (p 0.05). There was a positive relationship between the expression of HIF-1α, VEGF, MMP-2 and MVD (p < 0.01). Conclusions: CT perfusion imaging can reflect the blood perfusion of the rabbit VX2 liver tumors and evaluate the information of angiogenesis about tumors.

关键词： CT Perfusion Imaging VX2 Liver Tumor Vascular Endothelial Growth Factor Hypoxia-Inducible Factor-1 Alpha CD34 Molecule Microvessel Density

Climate and litter C/N ratio constrain soil organic carbon accumulation

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National Science Review 2019年第4期6卷 746-757页

作者： Guoyi Zhou Shan Xu Philippe Ciais Stefano Manzoni Jingyun Fang Guirui Yu xuli Tang Ping Zhou Wantong Wang Junhua Yan Gengxu Wang Keping Ma Shenggong Li Sheng Du Shijie Han Youxin Ma Deqiang Zhang Juxiu liu Shizhong liu Guowei Chu Qianmei Zhang Yuelin Li Wenjuan Huang Hai Ren Xiankai Lu Xiuzhi Chen South China Institute of Botany Chinese Academy of Sciences Institute of Ecology Jiangsu Key Laboratory of Agricultural Meteorology Nanjing University of Information Science & Technology Institut Pierre Simon Laplace Laboratoire des Sciences du Climat et de l'Environnement CEA CNRS UVSQ UPSaclay Department of Physical Geography Stockholm University Bolin Centre for Climate Research Institute of Botany Chinese Academy of Sciences Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Guangzhou Institute of Geography Guangdong Academy of Sciences College of Tourism Henan Normal University Institute of Mountain Hazards and Environment Chinese Academy of Sciences Institute of Soil and Water Conservation Chinese Academy of Sciences Institute of Applied Ecology Chinese Academy of Sciences Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences

Soil organic carbon(SOC) plays critical roles in stabilizing atmospheric CO2concentration, but the mechanistic controls on the amount and distribution of SOC on global scales are not well understood. In turn, this has hampered the ability to model global C budgets and to find measures to mitigate climate change. Here, based on the data from a large field survey campaign with 2600 plots across China’s forest ecosystems and a global collection of published data from forested land, we find that a low litter carbon-to-nitrogen ratio(C/N) and high wetness index(P/PET, precipitation-to-potentialevapotranspiration ratio) are the two factors that promote SOC accumulation, with only minor contributions of litter quantity and soil texture. The field survey data demonstrated that high plant diversity decreased litter C/N and thus indirectly promoted SOC accumulation by increasing the litter quality. We conclude that any changes in plant-community composition, plant-species richness and environmental factors that can reduce the litter C/N ratio, or climatic changes that increase wetness index, may promote SOC accumulation. The study provides a guideline for modeling the carbon cycle of various ecosystem scales and formulates the principle for land-based actions for mitigating the rising atmospheric CO2concentration.

关键词： litter carbon-to-nitrogen wetness index annual litterfall soil texture soil organic carbon

Programmable dual responsive system reconstructing nerve interaction with small-diameter tissue-engineered vascular grafts and inhibiting intimal hyperplasia in diabetes

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Bioactive Materials 2022年第1期7卷 466-477页

作者： Yanzhao Li Yeqin Wang Fangchao Xue xuli Feng Zhaojing Ba Junjie Chen Zhenhua Zhou Yanhong Wang Ge Guan Guanyuan Yang Ziwei Xi Hao Tian Yong liu Ju Tan Gang Li Xiewan Chen Mingcan Yang Wen Chen Chuhong Zhu Wen Zeng Department of Anatomy National and Regional Engineering Laboratory of Tissue EngineeringState and Local Joint Engineering Laboratory for Vascular ImplantsKey Lab for Biomechanics and Tissue Engineering of ChongqingThird Military Medical UniversityChongqing400038China Department of Cell Biology Third Military Army Medical UniversityChongqing400038China Innovative Drug Research Centre of Chongqing University Chongqing401331China Departments of Neurology Southwest HospitalThird Military Medical UniversityChongqingChina Medical English Department Third Military Medical UniversityChongqing400038China The 8th Medical Center of Chinese PLA General Hospital Beijing100091China Department of Plastic and Aesthetic Surgery Southwest HospitalThird Military Medical UniversityChongqingChina State Key Laboratory of Trauma Burn and Combined InjuryChongqingChina

Small-diameter tissue-engineered vascular grafts(sdTEVGs)with hyperglycemia resistance have not been *** intimal hyperplasia caused by hyperglycemia remains problem to hinder the patency of ***,inspired by bionic regulation of nerve on vascular,we found the released neural exosomes could inhibit the abnormal phenotype transformation of vascular smooth muscle cells(VSMCs).The transformation was a prime culprit causing the intimal hyperplasia of *** address this concern,sdTEVGs were modified with an on-demand programmable dual-responsive system of ultrathin *** external primary Reactive Oxygen Species(ROS)-responsive Netrin-1 system was initially triggered by local inflammation to induce nerve remolding of the sdTEVGs overcoming the difficulty of nerve regeneration under ***,the internal secondary ATP-responsive DENND1A(guanine nucleotide exchange factor)system was turned on by the neurotransmitter ATP from the immigrated nerve fibers to stimulate effective release of neural *** results showed nerve fibers grow into the sdTEVGs in diabetic rats 30 days after *** day 90,the abnormal VSMCs phenotype was not detected in the sdTEVGs,which maintained long-time patency without intima *** study provides new insights to construct vascular grafts resisting hyperglycemia damage.

关键词： sdTEVGs On-demand programmed responsive systems Neural exosomes Nerve reconstruction Intimal hyperplasia

汽车通风盘式制动器的摩擦学性能测试和流固热耦合仿真

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汽车工程 2017年第6期39卷 675-682页

作者：张森肖林京刘强周坤朱绪力山东科技大学机械电子工程学院青岛266590

根据摩擦微凸理论和耦合控制方程组分析了汽车通风盘式制动器的弹塑性状态转变条件和对流换热机理,通过乘积解法实现了通风盘的三维传热计算;基于Link 3900 NVH测试台对制动器的平均摩擦因数和摩擦稳定系数进行了测试,得出制动速度、制... 详细信息

根据摩擦微凸理论和耦合控制方程组分析了汽车通风盘式制动器的弹塑性状态转变条件和对流换热机理,通过乘积解法实现了通风盘的三维传热计算;基于Link 3900 NVH测试台对制动器的平均摩擦因数和摩擦稳定系数进行了测试,得出制动速度、制动压力和温度对其摩擦学性能的影响;建立了制动器的流固热数值仿真模型,利用MPCCI平台实现了ABAQUS热固耦合和FLUENT流固耦合的同步迭代,通过耦合节点的数据共享与交换得出盘体的瞬态温度场、应力场和耦合面的对流换热系数。结果表明,在单制动周期内通风盘表面的温度变化的数值模拟值与试验值基本一致,最大偏差仅为5.6%,这对于通风盘式制动器的性能评价和结构优化有着重要的指导意义。

关键词：通风盘式制动器摩擦因数台架试验流固热耦合数值模拟

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三次均匀B样条扩展曲线的渐进迭代逼近法

计算机辅助设计与图形学学报 2019年第6期31卷 899-910页

作者：刘成志韩旭里李军成中南大学数学与统计学院长沙410083 湖南人文科技学院数学与金融学院娄底417000

为了得到收敛速度更快的几何迭代法,提出带形状参数的三次均匀B样条扩展曲线的(加权)渐进迭代逼近法.首先基于三次均匀B样条扩展曲线提出(加权)渐进迭代逼近法的迭代格式;然后通过分析迭代矩阵的谱半径,探讨迭代法的最优形状参数及加权... 详细信息

为了得到收敛速度更快的几何迭代法,提出带形状参数的三次均匀B样条扩展曲线的(加权)渐进迭代逼近法.首先基于三次均匀B样条扩展曲线提出(加权)渐进迭代逼近法的迭代格式;然后通过分析迭代矩阵的谱半径,探讨迭代法的最优形状参数及加权渐进迭代逼近法的最优权系数;最后指出双三次均匀B样条扩展曲面同样具有(加权)渐进迭代逼近性质.数值实例结果表明,所求的最优形状参数及权系数使得迭代法具有最快的收敛速度.

关键词：三次均匀B样条的扩展曲线形状参数渐进迭代逼近法谱半径

基于多年环境特征的东北春玉米时空型种植区划研究

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农业机械学报 2017年第6期48卷 125-131页

作者：刘哲刘玮昝糈莉封伟李绍明张晓东中国农业大学信息与电气工程学院北京100083

玉米是我国主要粮食作物之一,现有的玉米种植环境区划受尺度过大的影响,分区环境特征不能满足品种精细测试要求,只用多年平均值描述环境空间特征,对于多环境测试中的环境不能充分地认知。为此,以地理网格为单元,以东北三省为研究区,利... 详细信息

玉米是我国主要粮食作物之一,现有的玉米种植环境区划受尺度过大的影响,分区环境特征不能满足品种精细测试要求,只用多年平均值描述环境空间特征,对于多环境测试中的环境不能充分地认知。为此,以地理网格为单元,以东北三省为研究区,利用东北三省21年的气象、DEM、坡度和县域春玉米种植面积等数据,以每年的环境特征为指标,构建多年环境特征数据库,通过属性聚类方法,从时空角度研究玉米种植环境精细区划方法,将东北三省的多年环境特征分成7类,使用类别归属度分析方法,实现东北三省玉米种植环境时空型区划。与多年环境特征均值的空间型区划对比结果表明,时空型区划结果更加精细,环境认知更加充分。

关键词：玉米种植环境多环境测试空间型区划时空型区划类别归属度

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作物遥感精细识别与自动制图研究进展与展望

农业机械学报 2018年第12期49卷 1-12页

作者：刘哲刘帝佑朱德海张琳昝糈莉童亮中国农业大学土地科学与技术学院北京100083 中国农业大学农业农村部农业灾害遥感重点实验室北京100083 中国农业大学信息与电气工程学院北京100083

作物识别与制图产品数据是作物长势、风险胁迫、产量等生产参量监测预测,种植结构调整与供需决策分析,以及耕地资源安全与生态效应评估等工作的基础数据,遥感数据成为作物类型识别与制图的最主要数据源,新兴数字技术则为遥感作物识别与... 详细信息

作物识别与制图产品数据是作物长势、风险胁迫、产量等生产参量监测预测,种植结构调整与供需决策分析,以及耕地资源安全与生态效应评估等工作的基础数据,遥感数据成为作物类型识别与制图的最主要数据源,新兴数字技术则为遥感作物识别与制图提供了新的方法手段。本文通过综述近年基于遥感的作物识别与制图相关研究成果,探究当前技术趋势、关键问题,以及需求差距。分别从小尺度作物精细识别、大尺度作物自动化制图,以及作物识别与制图模式变化3个视角总结归纳面临的主要问题和主要研究工作。作物识别与制图产品在小尺度上需要更加精细、近实时和更高的识别精度,主要使用超高空间分辨率(如米级、亚米级)的影像数据,在提高作物识别精度(95%以上)进而提取满足应用需求的高精度作物表型等信息方面依旧面临巨大挑战。而在大尺度上需要更加自动化、满足可靠识别精度(90%左右),主要使用高时空分辨率(2～5 d,10～30 m)的影像数据,面临着如何处理海量数据的存储管理、分析计算,发展大范围上具有鲁棒性的分类识别方法,寻找科学高效的地面样本获取途径的难题。同时,作物识别与制图的模式也将从确认监测向提前预判和特定作物探测转变。最后从加强科学研究与加快应用落地2个角度提出展望,为发展满足智慧农业与国土监管不同需求的遥感作物识别与制图产品提供参考与借鉴。

关键词：作物识别遥感自动化研究进展

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德意志官房学派的国家生产性思想传统探究

税收经济研究 2022年第3期27卷 86-95页

作者：刘守刚朱许丽上海财经大学公共经济与管理学院

活跃于17至18世纪尚未统一的德意志诸邦国的官房学派,为德意志经济社会发展做出了理论指引、人才培养和实践操作的贡献.在官房学者看来,国家的角色是积极的,因而主张基于君主与臣民的利益一致前提,以富国强兵为目标,用积极干预的手段来... 详细信息

活跃于17至18世纪尚未统一的德意志诸邦国的官房学派,为德意志经济社会发展做出了理论指引、人才培养和实践操作的贡献.在官房学者看来,国家的角色是积极的,因而主张基于君主与臣民的利益一致前提,以富国强兵为目标,用积极干预的手段来实现国家治理.这些官房学者致力于研究君主财产的经营与管理,想方设法管理经营王国的矿山、林地、工商企业,推动了诸邦国经济的快速发展,也让国家承担起明显的生产性角色。官房学派对国家生产性理论的论证,对后来历史学派国民经济学和社会政策学派指导德国国家发展产生了积极影响。当下,我国主流财政理论受英语财政学传统影响,一定程度上接受了其国家非生产性定位的观念,这与中国财政实践存在背离。批判地吸取官房学派有关国家生产性的思想传统,对我国财政学理论发展和创新具有积极意义。

关键词：官房学派国家生产性德语传统财政学英语传统财政学

Excessive nitrogen supply accelerates decline of old-growth forest by actuating Phosphorus limitation

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Excessive nitrogen supply accelerates decline of old-growth ...