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Cell Research 1991年第1期 35-43页

作者： GAO QIRONG, konghua zhang, LONGSHENG HONG,CHENGTANG XU AND GUOYAN GU (formerly KUOYENKU)Shanghai Institute of Cell Biology, Academia Sinica

The region between the preexisting and nascentmembranes of a cleaving Rana egg is a dense protrusionregion of nearly 40μm wide at 180°***,thisregion differentiate,into an upper part,a strip withlong, branched and randomly distributed protrusionswhich are derived largely from the preexistingmembrane,and a lower part,a band with *** 4-and 8-cel1 stages,the strip is almost vanishedand microvilli in the band is *** nascentmembrane is smooth at the 180°stage,then a rough areaappears below the smooth region and quickly *** germ agglutinin which can bind to preexistingmembrane interrupts the development of the regionbetween the preexisting and nascent ***,Brij,having the property to increase the areaof nascent membrane,does not interrupt the developmentof the region between the preexisting and nascentmembranes.

关键词： Gleavaqe region between the preexisting and nascent membranes surface active agents wheat germ agglutinin Rana amurensis eggs.

Laser scanning fluorescence microscopic measurement of the movement of cleaving egg surface of Rana Amurensis

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Cell Research 1995年第1期5卷 9-24页

作者： GU GUOYAN (FORMERLY KU KUOYEN) CHENGTANG XU konghua zhang QIRONG GAO.(Shanghai Institute of Cell Biology, Chinese Academy of Sciences, Shanghai 200031, China) Shanghai Institute of Cell Biology Chinese Academy of Sciences Shanghai 200031 China.&#x0002A Dedicated to Prefessor Zhen YAO on the occasion of his 80th birthday.† This work was supported by the director's foundation of Shanghai Institute of Cell BiologyReceived 27October1994 Revised 6April1995 Accepted 25April1995

By laser scanning fluorescence microscopy for quan-titative measurement of fluorescence intensity changes on egg surface stained with fluorescein isothiocyanate duxing cleavage furrow extending forward, it was found that in area of presumptive cleavage furrow the scanning curve became ∨ shape, indicating dark stripe appeared in that place. Then the fluorescence intensity increased at the place where the botton of ∨ shape had located, and the scanning curve tuxned to ∧ shape, indicating single stripe was formed. While enhanced fluorescence appeared on the borders of ∧ shape, an M shape curve was found, show-ing double stripe occurred. During the distance between two borders of M shape incresing from 50 μm to 100μm,a fluorescence peak came to sight in the middle of the M shape, which being the cleavge furrow bottom. The two lateral sides of furrow bottom with decreasing fluorescence were nascent membrane. At that time the curve became W shape. By the sides of cleavage furrow the the stress folds became conspicous after double stripe stage, showing the stretching of the egg surface being increased. With our[31, 33] and others[32] reports that polylysine could induce the appearance of nascent membrane and phyto-hemagglutinins could decrease or prevent the appearance of nascent membrane, we believed the idea of Schroeder[25] that increasing mechanical stress could initiate nascent membrane formation and thought that the stress lay to the outsides of cleavage furrow.

关键词： cleavage egg surface movement initiating nascent membrane formation laser scanning fluorescence microscopy Rana Amurensis

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高压减压阀气动参数设计与计算

流体机械 2024年第6期52卷 33-40页

作者：梁东奇冯浩波刘佳薇张帅张旭东杨孔华北京新风航天装备有限公司北京100854 湖北航天技术研究院总体设计所武汉430040 吉林大学机械与航空航天工程学院长春130022

为了研究减压阀在气动系统中工作时的静态特性,对减压阀内流场进行了建模、仿真以及试验验证,通过SST k-ω模型求解减压阀内速度场和压强场,并推导出高压减压阀流量、进、出口压强、阀门开口高度等参数之间的关系,得到减压阀在气动系统... 详细信息

为了研究减压阀在气动系统中工作时的静态特性,对减压阀内流场进行了建模、仿真以及试验验证,通过SST k-ω模型求解减压阀内速度场和压强场,并推导出高压减压阀流量、进、出口压强、阀门开口高度等参数之间的关系,得到减压阀在气动系统工作过程中进、出口压强变化曲线,并分析了不同参数对减压阀减压性能的影响。结果表明:减压阀弹簧刚度增加会影响出口压强和进口压强的变化趋势;活塞面积和限流孔直径对减压阀的出口精度有着显著影响,当限流孔直径为2.4 mm的减压阀的活塞面积从18.5 mm2提高至58.7 mm2时,出口压强精度可以从7%提升至1%;当活塞面积为58.7 mm2的减压阀的限流孔直径从2.4 mm增加至3.2 mm时,出口压强精度从7%降低至10%。研究结果可为同类减压阀的设计提供参考。

关键词：数值模拟减压阀有限元理论计算

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数码视觉疲劳症的流行病学调查及其对工作能力的影响

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护理研究（中旬版） 2017年第4期31卷 1390-1392页

作者：李孔华张芹湖北医药学院附属随州医院

[目的]调查分析数码视觉疲劳症(digital eye fatigue,DEF)的流行病学特征,探讨其对工作能力的影响。[方法]对2 764名体检对象进行流行病学调查,采用工作能力指数量表对其工作能力进行评价。[结果]DEF患病率为42.5%,男性患病率(57.0%)高... 详细信息

[目的]调查分析数码视觉疲劳症(digital eye fatigue,DEF)的流行病学特征,探讨其对工作能力的影响。[方法]对2 764名体检对象进行流行病学调查,采用工作能力指数量表对其工作能力进行评价。[结果]DEF患病率为42.5%,男性患病率(57.0%)高于女性(29.8%)(χ2=12.317,P<0.01),DEF患病人群平均年龄(26.31岁±5.22岁)低于总体调查人群(34.00岁±7.08岁)(t=-6.234,P<0.05);DEF主要表现为干眼、视物模糊、刺激症状、躯体不适以及调节功能紊乱等;DEF病人工作能力得分(27.12分±2.66分)低于非DEF(36.40分±3.38分)(t=-6.758,P<0.05)。[结论]DEF的流行现状不容忽视,且可能降低工作能力,应提升和改善人们对DEF的认知水平和健康行为。

关键词：数码视觉疲劳症工作能力流行病学年龄性别健康教育

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森林公安文化体系框架设计探讨

林业资源管理 2015年第6期 54-58页

作者：陈勇卢维英张弛敖孔华南京森林警察学院中国人民公安大学公安管理系国家林业局森林公安局

森林公安文化建设是一项战略性、系统性、长期性任务,需要系统构建、持续推进、有效管理。以公安文化"三层次论"为指导,以卓越文化建设的6个基本要求为参照,立足实现理念层、认知层、行为层等3个层面有效衔接的需要,围绕理念体系、内容... 详细信息

森林公安文化建设是一项战略性、系统性、长期性任务,需要系统构建、持续推进、有效管理。以公安文化"三层次论"为指导,以卓越文化建设的6个基本要求为参照,立足实现理念层、认知层、行为层等3个层面有效衔接的需要,围绕理念体系、内容体系、载体体系、保障体系等4个子体系构建森林公安文化体系框架,对于完善森林公安文化建设顶层设计,推进森林公安文化建设的系统化、体系化、科学化具有积极意义。

关键词：森林公安文化体系框架设计

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缺血性脑中风的发病机理探讨

河南中医 2006年第7期26卷 7-9页

作者：赵孔华张沁园平原县第一人民医院山东平原253100 山东中医药大学山东济南250014

缺血性脑中风包括短暂性缺血发作、脑血栓形成和脑栓塞。其病位在脑之脉络。病理基础以痰瘀为主,脏虚为本,痰瘀为标;痰瘀互结、阻络壅窍是中风发病的直接原因。治疗原则有三:醒脑开窍,法重急救;痰瘀并治,法重通络;活血化瘀,法贯始终。

关键词：缺血性脑中风发病机理治疗原则

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