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Using the Phosphomannose Isomerase (PMI) Gene from Saccharomyces cerevisiae for Selection in Rice Transformation

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Journal of Integrative Agriculture 2012年第9期11卷 1391-1398页

作者： WANG Tao LIU Liang-yu TANG Yong-yan zhang Xiao-bo zhang Mei-dong zheng Yong-lian zhang Fang-dong National Key Laboratory of Crop Genetic Improvement Ministry of Science and Technology/Huazhong Agricultural University Wuhan 430070P. R. China

The phosphomannose isomerase （PMI） gene from Saccharomyces cerevisiae acted as selectable marker and mannose acted as selective agent for the production of transgenic plants of rice （Oryza sativa L.） via Agrobacterium-mediated transformation. The concentration of mannose during the selection was stepwise increased, 5 g L-1 mannose combined with 15 g L-1 sucrose and 500 mg L-1 cefotaxime was used in the initial selection stage, then the concentration of mannose was increased to 11 g L-1, the highest transformation rate was 20.0%. The integration of PMI gene was confirmed by PCR, and the result of RT-PCR assay proved that the intron of PMI gene can be excised correctly during RNA splicing. 13- Glucuronidase （GUS） activity analysis confirmed the expression of GUS gene. All those means the PMI gene from yeast can be used as a selectable marker in rice transformation.

关键词： phosphomannose isomerase selectable marker Saccharomyces cerevisiae transformation rice

Preoperative assessment of hilar cholangiocarcinoma:combination of cholangiography and CT angiography

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Hepatobiliary & Pancreatic Diseases International 2010年第2期9卷 186-191页

作者： Yu, Shi-An zhang, Cheng zhang, Jia-Min Mao, Gen-Jun Xu, Long-Tang Wu, Xiao-Kang Shu, Jin-Er Lv, Guang-Hong zheng, zhang-dong Jinhua Cent Hosp Dept Gen Surg Jinhua 321000 Peoples R China Wenzhou Med Coll Wenzhou 325035 Peoples R China

BACKGROUND: Hilar cholangiocarcinoma is one of the most difficult carcinomas to manage because of the location of the main tumor at the hepatic hilus and the complex anatomy of the biliary, arterial, and portal systems. To plan an operation, it is important to acquire accurate information about the relationship between hilar cholangiocarcinoma and adjacent vessels. This study aimed to evaluate the clinical value of cholangiography combined with spiral CT three-dimensional (3D) angiography for a preoperative assessment of hilar cholangiocarcinoma. METHODS: From March 2007 to August 2009, cholangiography was performed in 13 patients with hilar cholangiocarcinoma. Meanwhile, contrast-enhanced abdominal scanning was performed using 16-slice spiral CT, and the 3D images of the hepatic artery and portal vein were acquired. The level and range of invasion of the hepatic artery, the portal vein, and the bile duct, the preoperative Bismuth classification, and T-staging were recorded and compared with those after surgical exploration. RESULTS: The hepatic artery and portal vein were reconstructed successfully in all these patients. Percutaneous transhepatic cholangiography was performed in 9 patients, endoscopic retrograde cholangiopancreatography in 1, and magnetic resonance cholangiopancreatography in 3. The CT angiography records of invasion of the hepatic artery were consistent with the results of explorations in these patients. The data from 5 of the 13 patients were consistent with those on invasion of the portal vein. The results of the Bismuth classification and the T-staging system were consistent with those of surgical exploration in 12 of the 13 patients. Seven of 8 patients who were estimated to be suitable for operation based on images were curatively treated and 5 who were judged to be unsuitable for curative operation by cholangiography and CT angiography were confirmed intraoperatively and underwent palliative procedures. CONCLUSIONS: Cholangiography combined

关键词： hilar cholangiocarcinoma cholangiography angiography spiral-computed tomography

Pathogenesis and treatment to postoperative bile leakage: report of 38 cases

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Hepatobiliary & Pancreatic Diseases International 2005年第3期4卷 441-444页

作者： Jia-Min zhang,Shi-An Yu,Wei Shen and zhang-dong zheng Jinhua Centre Hospital, Jinhua 321000 , China Jinhua Centre Hospital Jinhua 321000 China. zhangjiamin 600323@.***

Bile leakage remains a serious complication after biliary surgery. The aim of this study was to assess the etiology, diagnosis and treatment of postoperative biliary leakage. METHODS:Thirty-eight patients with biliary leakage we treated in recent 8 years were analyzed retrospectively. Among them, 8 patients had bilioenterostomy leakage, 7 accessory bile duct leakage, 7 cholecyst bed leakage, 6 leakage after removal of T-tube, 5 leakage after laparoscopic cholecystectomy, 3 leakage around T-tube, and 2 leakage caused by choledochal damage. Drainage was performed in 17 patients, reoperarion in 13, drainage plus percutaneous transhepatic cholangio drainage (PTCD) , endoscopic retrograde cholangiography (ERCP) , endoscopic nasobiliary drainage(ENBD) and endostenting in 5, and drainage plus growth hormone in 3. RESULTS; In this series, 37 patients were cured, and 1 died of multiple organ dysfunction syndrome (MODS). These patients were hospitalized for 2 weeks to 8 weeks. The drainage group was hospitalized shorter than the undrain-age group. CONCLUSIONS; A piece of white gauze can be used to touch surgical area in detecting biliary leakage intraopera-tively. Mucous to mucous suture of the bile duct and appropriate time for removal of T-tube are recommended to prevent biliary leakage. Reoperation is essential to acute peritonitis. Drainage can be used if leakage don t diffuse or it occurs after pulling out T-tube. Drainage plus ERCP, ENBD,PTCD and drainage are effective.

关键词： etiology treatment complication biliary leakage

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珠江河口地区可持续发展评价研究

地理科学 2005年第1期25卷 29-35页

作者：张正栋嘉应学院地理系

未来发展对珠江河口区的资源环境承载能力和生态服务功能提出了前所未有的要求,在此认识基础上,构建了基于资源承载力的可持续发展评价指标体系,并进行了河口区发展水平、可持续性水平、可持续发展能力及其可持续发展状态变化的定量分析... 详细信息

未来发展对珠江河口区的资源环境承载能力和生态服务功能提出了前所未有的要求,在此认识基础上,构建了基于资源承载力的可持续发展评价指标体系,并进行了河口区发展水平、可持续性水平、可持续发展能力及其可持续发展状态变化的定量分析,得出:①珠江河口区总体已进入经济资源驱动阶段;②在自然子系统、经济子系统、社会子系统中,社会子系统滞后;③可持续发展能力处于中等可持续发展水平。

关键词：可持续发展评价资源环境承载力经济资源驱动珠江河口区

35 a来海南岛耕地变化与人口经济发展间的相关分析

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中国沙漠 2005年第5期25卷 757-763页

作者：张正栋中国科学院广州地球化学研究所

采用1970—2004年的统计资料,用统计方法,研究了近35a来海南岛耕地变化过程与人口增长、经济发展之间动态变化关系,建立了耕地资源减少量与人口总数、固定资产投资总额、人均GDP和城市化水平间的三个曲线相关模型。结果表明:①35a来海... 详细信息

采用1970—2004年的统计资料,用统计方法,研究了近35a来海南岛耕地变化过程与人口增长、经济发展之间动态变化关系,建立了耕地资源减少量与人口总数、固定资产投资总额、人均GDP和城市化水平间的三个曲线相关模型。结果表明:①35a来海南岛耕地资源变化的最主要驱动力是国家政策引导和调控下的人类社会经济活动。②海南岛人口增长、经济发展与耕地面积变化之间存在着比较明显的呈类似库兹涅茨曲线倒“U”型关系,耕地减少量呈现先减小后增大再减小的趋势。③从优化耕地库兹涅茨曲线的角度出发,提出了现阶段协调人口增加、经济发展与耕地保护的政策建议:加快现代土地市场体系建设,提高土地资源市场化配置程度,将土地利用的外部性内部化;进一步明晰产权,改革征地制度,强化耕地管制手段;建立有效的土地利用技术创新机制和技术体系;强化最严格保护耕地的意识。

关键词：经济发展人口增长耕地资源库兹涅茨曲线政策建议海南岛

四种扑动方式对水下扑翼推进性能影响数值分析

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工程力学 2018年第4期35卷 249-256页

作者：杜晓旭张正栋西北工业大学航海学院陕西西安710072

为了对比四种最常见的扑动方式对水下扑翼推进性能的影响规律,研究其对流场的影响机理,分别建立二自由度水下刚性扑翼计算模型。基于Realizable k-ε湍流方程,利用有限体积法(FVM)求解非定常雷诺平均N-S(URANS)方程,结合动网格技术对不... 详细信息

为了对比四种最常见的扑动方式对水下扑翼推进性能的影响规律,研究其对流场的影响机理,分别建立二自由度水下刚性扑翼计算模型。基于Realizable k-ε湍流方程,利用有限体积法(FVM)求解非定常雷诺平均N-S(URANS)方程,结合动网格技术对不同扑动方式下的扑翼非定常水动力性能展开数值计算,并对流场结构进行分析,揭示其影响规律。计算结果表明:四种扑动方式对扑翼推进性能的影响明显,方式3能够产生最大的平均推力,且整体不产生阻力,方式1次之,方式2与方式4不产生平均推力;四种扑动方式产生的平均升力均为0左右,但是方式1升力峰值最大,方式3升力峰值最小。

关键词：流体力学扑翼动网格推进性能流线

自主水下航行器回收过程中螺旋桨推力特性分析

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兵工学报 2017年第6期38卷 1154-1160页

作者：杜晓旭张正栋西北工业大学航海学院陕西西安710072

在自主水下航行器(AUV)水下回收过程中,螺旋桨的推力特性对AUV的稳定性控制及安全性能等影响非常明显。主要基于计算流体力学方法,采用多块混合网格技术结合RNG k-ε湍流模型,对AUV在不同回收工况下的螺旋桨推力特性展开数值模拟。建立... 详细信息

在自主水下航行器(AUV)水下回收过程中,螺旋桨的推力特性对AUV的稳定性控制及安全性能等影响非常明显。主要基于计算流体力学方法,采用多块混合网格技术结合RNG k-ε湍流模型,对AUV在不同回收工况下的螺旋桨推力特性展开数值模拟。建立AUV及螺旋桨的三维几何模型;基于多块混合网格方法对计算域进行空间离散,同时采用动网格技术实现螺旋桨与回收管的相对运动及自身旋转运动;利用有限体积法展开数值计算。基于计算数据与试验数据的对比及数值无关性测试,表明所使用的多块混合网格方法能够对AUV回收过程螺旋桨推力特性进行准确计算,为AUV水下回收过程的控制及安全性能评估能够提供理论参考。

关键词：流体力学螺旋桨自主水下航行器多块混合网格推力特性