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A Confocal Technique Applicable to Studies of Cellular pH-related Signaling in Plants

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Journal of Integrative Plant Biology 2008年第6期50卷 682-690页

作者： Bing-Bing Lit Zhi-Hui Gao Xiao-Yan Zhou Hui-Bo Ren Min Xie Yi-Juan Fan jian-fang Hu wen-Suo Jia College of Agronomy and Biotechnology China Agricultural University Beijing 100094 China

pH may act as a crucial signal in both animal and plant cells. It is very difficult to monitor pH signals and this has largely hindered progress in the investigation of pH signaling, particulady systematic pH signaling. Here, we report the development of a confocal technique to monitor leaf apoplastic pH in intact plants, which is particularly suitable for the studies on root to shoot signaling. A variety of different pH indicators and plant species were tested. It was found that different pH indicators, for example, 2＇,7＇-Bis-（2-carboxyethyl）-5-（and-6）-carboxyfluoresce （BCECF）, SNARF-4F 5-（and-6）- carboxylic acid （SNARF） and DM-NERF （NERF）, were of different properties, and to successfully monitor pH at a sub-cellular level, the comparability between the pH indicator and plant species must be involved according to their suitable pH range and loading characteristics. The loading characteristics of different pH indicators differ with different plant species, cell types and their developing stages. No matter what methods were adopted, BCECF and SNARF could not be loaded specifically in the leaf apoplast in sunflower, tomato, and Comelina communis L. In contrast, regardless of the methods adopted, NERF could be loaded efficiently and specifically in the leaf apoplast in C. communis, but not in other plants. In C. communis, the determination coefficient for in vitro and in situ calibration of NERF was very high, which was respectively 0.9951 and 0.991 6, and therefore, the adoption of NERF together with C. communis could construct an ideal experimental system that is suitable for the investigation of pH systematic signaling. Ratio image analysis demonstrated that the leaf apoplastic pH was about 5.5 in non-stressed conditions, and water deficit could trigger an increase in pH by about half a pH unit, which is the first evidence to directly indicate that pH is able to act as a systematic signal under water deficit conditions.

关键词： confocal microscope pH signaling water deficit.

Killing effect of Chinese hamster V79 cells exposed to accelerated carbon ions and RBE determination

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Nuclear Science and Techniques 2002年第4期13卷 259-263页

作者： LI Qiang, ZHOU Guang-Ming, WANG Ju-fang, LI wen-jian, WEI Zeng-Quan(Institute of Modern Physics, the Chinese Academy of Sciences, Lanzhou 730000) Institute of Modern Physics the Chinese Academy of Sciences Lanzhou 730000

Survival curves of Chinese hamster V79 cells exposed to accclerated carbon ions with linear energy transfers of 125.5, 200 and 700 keV/μm were measured, respectively. Inactivation cross sections corresponding to the irradiation above were deduced from the V79 cell survival curves. They are 7.86±0.17, 10.44±1.11 and 32.32±3.58 μm2 in turn. With the surviving response of V79 cells to 60Co γ-rays as a reference value, relative biological effectiveness at 10%, 20%, 50% and 80% survival levels were given for the accelerated carbon ions. The results showed that carbon ions with LET of 125.5 keV/μm had a higher value of RBE at all the four survival levels than the carbon ions with other LETs. It was prompted that the maximum value of RBE for the V79 cell surviving as the biological endpoint emerged at the LET below 200 keV/μm for carbon ions.

关键词：放射生物学碳离子 V79细胞

Low dose effects on cultured mammalian cells...

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Nuclear Science and Techniques 2000年第4期11卷 276-279页

作者： WANG Ju-fang, LI wen-jian, ZHOU Guang-Ming, HE Jing, LI Qiang, DANG Bing-Rong, LI Xing-Lin, XIE Hong-Mei, WEI Zeng-Quan (Institute of Modern Physics, the Chinese Academy of Sciences, Lanzhou 730000) 中科院近代物理所甘肃兰州 730000

The low dose effects induced by carbon ions on Chinese hamster V79 cells and murine melanoma B16 cells were investigated in this paper. Both cell lines were divided into four groups for irradiation: (1) control, (2) 0.02 Gy or 0.05 Gy(D1), (3) 1 Gy(D2), (4) D1+D2. The survivors and micronuclei were studied as biological endpoints. The results of group (1) and group (2) showed that there were no obvious differences on micronucleus frequency but there were significant increases when irradiation dose was 0.02Gy on colony formation efficiency. Although low dose ion irradiation could not contribute to DNA damages, it could enhance the colony formation efficiency. In the study of group (3) and (4), when the ion dose was 0.02 Gy, there were evident increases on surviving fraction and decreases on micronucleus frequency, but there were no statistical changes on these endpoints when the ion dose was 0.05Gy. This meant that high LET radiation could induce the adaptive response of cultured cells, furthermore, in the range of inducing ion dose , low dose irradiation was more profitable than high dose one.

关键词：哺乳动物细胞 DNA 离子辐射低剂量效应辐射效应碳离子

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壳聚糖酶的分离提纯及其酶学性质研究

高校化学工程学报 2007年第5期21卷 814-819页

作者：隋斯光方文建郑连英浙江大学化学工程与生物工程学系浙江杭州310027

从土壤中筛选获得的高产壳聚糖酶菌株Penicillium ***-Z1,经发酵、分离提取出两种壳聚糖酶A和酶B,并对它们分别进行酶学性质测试。分别测定酶A和酶B的等电点、相对分子质量、最适反应温度和pH、不同脱乙酰度的壳聚糖对酶活的影响。并考... 详细信息

从土壤中筛选获得的高产壳聚糖酶菌株Penicillium ***-Z1,经发酵、分离提取出两种壳聚糖酶A和酶B,并对它们分别进行酶学性质测试。分别测定酶A和酶B的等电点、相对分子质量、最适反应温度和pH、不同脱乙酰度的壳聚糖对酶活的影响。并考察了两种壳聚糖酶的酶解方式,结果表明,酶A为内切酶,酶B为外切酶。

关键词：壳聚糖酶 Penicillium sp 分离纯化酶学性质

外商直接投资技术溢出机制研究——基于江苏省制造业面板数据的实证分析

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数理统计与管理 2010年第5期29卷 761-769页

作者：方健雯赵增耀苏州大学商学院江苏苏州215021

本文利用2000-2007年江苏省制造业的面板数据,对外商直接投资水平溢出效应和垂直溢出效应进行了检验。结果表明,江苏省外商直接投资存在显著的水平溢出效应、后向溢出效应和前向溢出效应,但水平溢出效应较垂直溢出效应更为明显。并且水... 详细信息

本文利用2000-2007年江苏省制造业的面板数据,对外商直接投资水平溢出效应和垂直溢出效应进行了检验。结果表明,江苏省外商直接投资存在显著的水平溢出效应、后向溢出效应和前向溢出效应,但水平溢出效应较垂直溢出效应更为明显。并且水平溢出效应和前向溢出效应显示为边际递减,而后向溢出效应的影响是持久的。

关键词：水平溢出前向溢出后向溢出

集群情境下企业创新投入的影响因素研究——基于苏州制造业数据的实证分析

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预测 2012年第1期31卷 1-7页

作者：方健雯赵增耀苏州大学东吴商学院江苏苏州215021

本文研究集群情境下企业创新投入的影响因素,并利用苏州制造行业中3090家企业的数据进行了实证检验。研究发现产业集群能促进企业创新投入强度的提高;由于复杂知识的排他性,集群中的高技术企业会进一步加大创新投入,但聚集效应对创新投... 详细信息

本文研究集群情境下企业创新投入的影响因素,并利用苏州制造行业中3090家企业的数据进行了实证检验。研究发现产业集群能促进企业创新投入强度的提高;由于复杂知识的排他性,集群中的高技术企业会进一步加大创新投入,但聚集效应对创新投入的影响还与集群知识分布的不对称性有关。由于具有外部技术来源,产业聚集中的外资企业会减少创新投入,但集群中采用市场机制进行创新的企业将会增加创新投入。

关键词：集群创新知识溢出

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激光光热反射技术对薄膜热物性的表征

中国激光 2006年第3期33卷 385-390页

作者：陈赵江方健文王志海浙江师范大学数理学院浙江金华321004

在考虑探测光束光斑尺寸对调制光热反射(MPR)信号影响的基础上,建立了三维的薄膜-衬底体系的激光光热反射理论模型。对利用激光光热反射技术测量薄膜热物性的可行性进行了研究,并对影响调制光热反射信号的材料参数进行了分析。此外,通... 详细信息

在考虑探测光束光斑尺寸对调制光热反射(MPR)信号影响的基础上,建立了三维的薄膜-衬底体系的激光光热反射理论模型。对利用激光光热反射技术测量薄膜热物性的可行性进行了研究,并对影响调制光热反射信号的材料参数进行了分析。此外,通过数值模拟研究了多参数拟合问题,即利用调制光热反射频响信号同时确定薄膜热扩散率、衬底热扩散率和界面热阻这三个物理参数。结果表明,与已有的径向扫描方法相比,频率扫描方法中的这三个参数之间并不存在高度的相关性,因此采用频响信号进行多参数拟合,可提高多参数拟合的收敛性和精确性。

关键词：激光技术光热反射多参数拟合热扩散率界面热阻

基于PCA和网络DEA模型的中国工业企业研发效率和经营效率评价

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数理统计与管理 2014年第5期33卷 869-877页

作者：方健雯邱永和苏州大学东吴商学院江苏苏州215021 台湾东吴大学经济系

本文构建了一个价值链模型,将创新活动视作由研发阶段和经营阶段构成的完整过程。在主成分提取的基础上,利用Tone和Tsut8ui提出的SBM网络DEA模型,对2010年我国30个省(自治区、直辖市)大中型工业企业的研发效率和经营效率进行了实证分析... 详细信息

本文构建了一个价值链模型,将创新活动视作由研发阶段和经营阶段构成的完整过程。在主成分提取的基础上,利用Tone和Tsut8ui提出的SBM网络DEA模型,对2010年我国30个省(自治区、直辖市)大中型工业企业的研发效率和经营效率进行了实证分析。研究发现:第一,研发效率与经营效率之间不存在显著相关关系。第二,从整体上看,我国大中型工业企业的研发效率显著低于经营效率。第三,利用象限分析方法,根据研发效率和经营效率的特点,将我国各省市划分为高研发效率一高经营效率、高研发效率.低经营效率、低研发效率一高经营效率、低研发效率一低经营效率四种模式,并根据各种模式提出了有针对性的建议。

关键词：网络DEA模型主成分分析研发效率经营效率工业企业

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人源性肿瘤异种移植模型在眼科的应用进展

眼科新进展 2019年第7期39卷 695-697页

作者：方健文袁晴邵毅南昌大学第一附属医院眼科

人源性肿瘤异种移植模型为肿瘤发生机制的研究、肿瘤药物的筛选和癌症治疗方案的评估提供了良好的临床前试验模型。近年来,人源性肿瘤异种移植模型的建立和应用在肿瘤领域的发展不断进步,在对癌症的研究中发挥重要作用。本文主要介绍人... 详细信息

人源性肿瘤异种移植模型为肿瘤发生机制的研究、肿瘤药物的筛选和癌症治疗方案的评估提供了良好的临床前试验模型。近年来,人源性肿瘤异种移植模型的建立和应用在肿瘤领域的发展不断进步,在对癌症的研究中发挥重要作用。本文主要介绍人源性肿瘤异种移植模型在眼科肿瘤领域的应用进展。

关键词：人源性肿瘤异种移植模型视网膜母细胞瘤葡萄膜黑色素瘤脉络膜黑色素瘤结膜黑色素瘤