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A VARIATIONAL PRINCIPLE ON MAGNETOELASTIC INTERACTION OF FERROMAGNETIC THIN PLATES

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Acta Mechanica Solida Sinica 1997年第1期10卷 1-10页

作者： zhou, yh Zheng, XJ LANzhou UNIV DEPT MECHGANSU 730000PEOPLES R CHINA

The key to revealing the behaviors of magnetoelastic interaction is how to express the magnetic forces applying on a ferromagnetic elastic body. In this paper, a functional for a ferromagnetic thin plate in magnetic fields is proposed by taking the summation of the magnetic energy of the magnetic system and the strain energy of the elastic plates. We present a variational principle for the problem by choosing the variations of magnetic potential and deflection as independent variates each other. Based on the principle, not only are the simultaneous governing equations for magnetic fields and deformation of structures deduced, but also a general expression of magnetic force acting on the plates is gained, which makes it possible to commonly simulate the distinct two experiments of magnetoelastic interaction in a theoretical model. Thus, it can be used to theoretical prediction of the magnetoelastic interaction of ferromagnetic plates in a complex environment of applied magnetic fields.

关键词： magnetoelastic interaction variational principle expression of magnetic force ferromagnetic thin plates

Polar motion and the North Atlantic Oscillation

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Chinese Science Bulletin 1997年第11期42卷 927-931页

作者： zhou, yh Zheng, DW Chao, BF Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai China NASA Goddard Space Flight Center USA

THE motion of earth’s instantaneous rotation pole with respect to the earth crust or the mean pole of the epoch is briefly referred to as the polar *** polar motion is mainly charac-terized by the annual and Chandler polar *** data accumulation and promotion ofthe observation accuracy after the 1980s,people have extended researches of only annual

关键词： polar motion the North Atlantic Oscillation excitation function interannual time scale.

Simulation Structural Properties of Ni Clusters by Transferable Tight-binding Potential

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Journal of Materials Science & Technology 1999年第4期15卷 320-322页

作者： Luo, CL Cao, AJ zhou, yh Nanjing Normal Univ Dept Phys Nanjing 210097 Peoples R China

A transferable tight-binding potential for Ni has been developed. Molecular dynamics methods and simulated annealing techniques have been used to study the structural properties of Ni clusters with this potential. We have obtained the structures of some Ni clusters. The average coordination number, ionization potentials and the stability of clusters have also been calculated.

关键词： IONIZATION-POTENTIALS NICKEL CLUSTERS

GRAIN REFINEMENT INDUCED BY REMELTING INUNDERCOOLED Fe-30at.%Co ALLOYS

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Acta Metallurgica Sinica(English Letters) 1999年第6期12卷 0-0,0-0+0页

作者： M. J Li G.S. Song G.C. Yang and yh zhou (State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an 710072,China)

Fe-30at.%Co alloy is undereooled to investigate the effct of remelting on the grain size at certain undereooling rnnges. At low undereoolings, the primary stable fcc phase is remelted, which results in the equiaxed grains. When the melt is undercooled greater than the critical undereooling △T=204K the primary metastable bcc phase will alternatively nucleate in the melt. The primary bcc dendrite will be remelted into isolated dendrite cores dispersing in the remaining liquids. In the meanwhile, the isolated dendrite cores are remelted more or less due to the temperature fluctuation in the liquids. Different crystal structures between bcc and fcc phase make the subsequent crystal growth of fcc phase onto the Primary bcc phase non-epitaxial when the melt is undereooled greater than △T=204K. The primary metastable bcc phase may play an important role in coarsening grains in the systetn at larpe undereoolings.

关键词： undercooling microstructure Fe-Co alloy dendrite remelting

Post-acute ischemic stroke hyperglycemia aggravates destruction of the blood-brain barrier

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Neural Regeneration Research 2024年第6期19卷 1344-1350页

作者： Tianqi Xu Jianhong Yang Yao Xu Xiaofeng Wang Xiang Gao Jie Sun Chenhui zhou Yi Huang Department of Neurology The First Affiliated Hospital of Ningbo University Department of General Surgery The First Affiliated Hospital of Ningbo University Department of Neurosurgery The First Affiliated Hospital of Ningbo University Key Laboratory of Precision Medicine for Atherosclerotic Diseases of Zhejiang Province

Post-acute ischemic stroke hyperglycemia increases the risk of hemorrhagic transformation, which is associated with blood-brain barrier disruption. Brain microvascular endothelial cells are a major component of the blood-brain barrier. Intercellular mitochondrial transfer has emerged as a novel paradigm for repairing cells with mitochondrial dysfunction. In this study, we first investigated whether mitochondrial transfer exists between brain microvascular endothelial cells, and then investigated the effects of post-acute ischemic stroke hyperglycemia on mitochondrial transfer between brain microvascular endothelial cells. We found that healthy brain microvascular endothelial cells can transfer intact mitochondria to oxygen glucose deprivation-injured brain microvascular endothelial cells. However, post-oxygen glucose deprivation hyperglycemia hindered mitochondrial transfer and exacerbated mitochondrial dysfunction. We established an in vitro brain microvascular endothelial cell model of the blood-brain barrier. We found that post-acute ischemic stroke hyperglycemia reduced the overall energy metabolism levels of brain microvascular endothelial cells and increased permeability of the blood-brain barrier. In a clinical study, we retrospectively analyzed the relationship between post-acute ischemic stroke hyperglycemia and the severity of hemorrhagic transformation. We found that post-acute ischemic stroke hyperglycemia serves as an independent predictor of severe hemorrhagic transformation. These findings suggest that post-acute ischemic stroke hyperglycemia can aggravate disruption of the blood-brain barrier by inhibiting mitochondrial transfer.

关键词： acute ischemic stroke blood-brain barrier brain microvascular endothelial cells mitochondrial transfer stress hyperglycemia

中药复方制剂对大脑中动脉闭塞大鼠脑酪氨酸激酶受体B表达的影响

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中国组织工程研究与临床康复 2007年第12期11卷 2360-2362页

作者：周永红胡怀强王新陆青岛大学医学院中医教研室山东省青岛市266021 山东中医药大学山东省济南市250014

目的:观察中药复方对大脑中动脉闭塞模型大鼠脑内酪氨酸激酶受体B的影响,分析其促进神经发生的作用。方法:实验于2004-02/2004-04在山东省医学科学院病理实验室完成。普通级健康Wistar大鼠30只,12周龄,体质量(300±20)g,雌雄不限。采用... 详细信息

目的:观察中药复方对大脑中动脉闭塞模型大鼠脑内酪氨酸激酶受体B的影响,分析其促进神经发生的作用。方法:实验于2004-02/2004-04在山东省医学科学院病理实验室完成。普通级健康Wistar大鼠30只,12周龄,体质量(300±20)g,雌雄不限。采用随机数字表分为药物组、模型组、假手术组,每组10只。模型组和药物组制作大脑中动脉闭塞模型,假手术组大鼠行同样开颅术,但不凝闭大脑中动脉,其余操作同模型组。大脑中动脉闭塞模型制作按Tamura方法稍加改进,行右侧近端大脑中动脉电凝术。麻醉醒后24h内出现:①左侧肢体痛刺激收缩现象消失。②向左侧倾倒或转圈。③提尾时左上肢不能向前伸直。具备以上3项为大脑中动脉闭塞模型复制成功。药物组灌胃给予复健片(由山东鲁信药业有限公司生产,主要成分为何首乌、草决明、桑寄生、海马、淫羊藿等)水溶液10g/kg,余二组分别灌胃给予同等量生理盐水,1次/d,共2周,于造模成功后6d给药。免疫组化法观察大脑中动脉闭塞大鼠脑内酪氨酸激酶受体B的表达。采用Leica QwinV3图像分析系统对免疫组化切片进行图像分析,测定染色平均灰度。结果:30只大鼠均进入结果分析。模型组和药物组的酪氨酸激酶受体B表达染色平均灰度在给药一二周后较假手术组增加,给药2周后药物组的酪氨酸激酶受体B表达染色平均灰度高于模型组[模型组:给药1周后:107.29±4.29,给药2周后:109.60±6.38;药物组:给药1周后:113.18±12.67,给药2周后:123.51±2.82,假手术组:96.48±3.58,P<0.01,P<0.05]。结论:中药复方复健片可显著增强大脑中动脉闭塞大鼠脑内神经生长因子正性调控因子酪氨酸激酶受体B的表达。

关键词：中药脑缺血垂体卒中酪氨酸激酶受体B

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芳香酮不对称还原为醇的简便方法

中国医药工业杂志 2015年第1期46卷 3-3页

作者： zhou yh 朱怡君

芳香酮以（S）-Me-CBS为手性催化剂（10mol％），无水THF为溶媒，在NaBH4／Me2SO4体系中低温反应，可以得到相应的不对称还原产物芳香醇，7例收率为80％～99％，ee值为93％～98％，其中芳香环上卤素取代的收率较低，为80％～90％。

关键词：不对称还原芳香酮芳香醇简便手性催化剂 NaBH4 低温反应还原产物

运动状态下CT扫描后靶区三维重建的形变规律

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中国组织工程研究与临床康复 2007年第13期11卷 2487-2489,2493页

作者：徐子海廖福锡周燕华黄坚周志美解放军第三○三医院放疗中心广西壮族自治区南宁市530021

目的:观察呼吸运动对肺部靶区三维重建的影响。方法:用步进电机、步进电机驱动器、导轮、有机玻璃球、低密度度泡沫等设计能模拟肿瘤随呼吸运动的体模;取不同螺距(0.875,1.675,0.625mm)、不同层厚(8mm×1.25mm或8mm×2.50mm)和运动周期... 详细信息

目的:观察呼吸运动对肺部靶区三维重建的影响。方法:用步进电机、步进电机驱动器、导轮、有机玻璃球、低密度度泡沫等设计能模拟肿瘤随呼吸运动的体模;取不同螺距(0.875,1.675,0.625mm)、不同层厚(8mm×1.25mm或8mm×2.50mm)和运动周期组成6个不同的扫描序列在GE LightSpeed16CT上扫描,然后采用体绘制技术对所获得CT图像进行三维重建,用三维工具软件测量不同扫描条件下各靶体积大小,计算动态与静态扫描靶区重建体积的相对偏差。结果:静态模型同一靶区在层厚与螺距不同时,扫描后三维重建的靶区外形无明显变化,重建靶区的体积差异可忽略;在不同运动状态下扫描,同一靶区重建图像的外形差异明显,重建靶体积的相对偏差最大值为54.1%;同一运动状态下,各靶区重建体积变化随靶而异;外形较小的靶区重建体积相对偏差变化范围为-39.8%～54.1%,外形较大的靶区重建体积相对偏差变化范围是-18.4%～8.7%。结论:呼吸运动对靶区重建的响影极大,三维放疗计划设计所依赖的CT图像,必须是肿瘤靶区处于相对静止状态下扫描的图像,否则,适形射野和剂量体积直方图将严重失真。

关键词：呼吸运动模型三维重建康复工程

接受肾移植前维持性血液透析患者生活质量与静脉补充左旋卡尼汀的影响

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中国组织工程研究与临床康复 2007年第51期11卷 10242-10245页

作者：温黎青李建飞王芳芳周咏红广西医科大学第五附属医院柳州巿人民医院肾内科广西壮族自治区柳州市545001

目的:血液透析患者大多存在卡尼汀尤其是游离卡尼汀的缺乏,透析后补充左旋卡尼汀能够减轻、减少并发症及住院率。观察静脉补充左旋卡尼汀对肾移植前血液透析患者生活质量的影响。方法:选择2005-09/2006-09于柳州市人民医院进行维持性血... 详细信息

目的:血液透析患者大多存在卡尼汀尤其是游离卡尼汀的缺乏,透析后补充左旋卡尼汀能够减轻、减少并发症及住院率。观察静脉补充左旋卡尼汀对肾移植前血液透析患者生活质量的影响。方法:选择2005-09/2006-09于柳州市人民医院进行维持性血液透析的患者30例,对治疗方案均知情同意。按随机数字表法分为左旋卡尼汀组和对照组,每组15例。每次透析结束后,左旋卡尼汀组静脉注射左旋卡尼汀20mg/kg,对照组注射等量的生理盐水,用药8周。用药前及用药8周时分别应用SF-36量表进行生活质量评分,由8个方面组成,每项都以0￣100分计,得分越高表示生活质量越好;同时记录透析相关症状及实验室参数,比较两组间差异。结果:30例患者全部进入结果分析。①与用药前相比,用药8周后左旋卡尼汀组SF-36总体评分增加了(18.29±12.71)分,对照组总评分减少了(6.40±16.39)分。与对照组相比,左旋卡尼汀组总评分及生理功能、总体健康、活力、社会功能、精神健康评分均显著增加(P<0.05￣0.01)。②与对照组相比,左旋卡尼汀组血红蛋白、白蛋白含量均显著增加(P<0.01)。结论:静脉补充左旋卡尼汀不仅有助于改善维持性血液透析患者的贫血状况,而且能明显提高其生活质量。

关键词：血液透析肾移植肉碱生活质量