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中国商贸产业发展与结构变动的趋势研究 被引量:2
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作者 晏维龙 胡荣华 +1 位作者 HAN yao 《产业经济研究》 2001年第1期39-44,共6页
本文根据中国商贸产业发展的历史与逻辑,分析商贸发展与经济发展、城市发展,商贸发展中的内部结构、市场结构、产权结构、组织结构、业态结构、经营结构、技术结构的变化与调整等问题.
关键词 中国商贸产业 结构变动 趋势
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确定运行中的燃气轮机初温的方法探讨 被引量:5
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作者 郑莆燕 姚秀平 +9 位作者 齐进 张莉 ZHANG Li QI Jin yao Xiu-ping ZHENG Pu-yan 《燃气轮机技术》 2005年第1期57-59,共3页
受多方面因素的制约,目前还很难直接测量燃气轮机的运行初温,在许多情况下需采用理论方法确定。本文依据热力学和燃烧学基本原理,结合燃气轮机设备和系统的一些具体情况,提出了四种较切合工程实际的确定运行中燃气轮机初温的方法,并对... 受多方面因素的制约,目前还很难直接测量燃气轮机的运行初温,在许多情况下需采用理论方法确定。本文依据热力学和燃烧学基本原理,结合燃气轮机设备和系统的一些具体情况,提出了四种较切合工程实际的确定运行中燃气轮机初温的方法,并对每一种方法的使用作了分析。 展开更多
关键词 燃气轮机 燃气轮机初温 理论方法
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神经元膜NMDA受体蛋白免疫复合物单分子纳米结构及定位AFM比较研究(英文)
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作者 郁毅刚 徐如祥 +4 位作者 姜晓丹 蔡颖谦 柯以铨 Qian-Ming yao 《神经科学通报》 CSCD 2005年第2期117-128,共12页
目的 探讨NMDAr(N- 甲基- D- 天冬氨酸受体)在神经细胞膜表面定位,对比不同成像方法的特点,建立纳米尺度神经细胞膜表面蛋白单分子三维标记的免疫细胞化学新方法。方法 应用原子力显微镜,对分布在云母表面的抗NMDAR1亚单位IgG 葡萄球... 目的 探讨NMDAr(N- 甲基- D- 天冬氨酸受体)在神经细胞膜表面定位,对比不同成像方法的特点,建立纳米尺度神经细胞膜表面蛋白单分子三维标记的免疫细胞化学新方法。方法 应用原子力显微镜,对分布在云母表面的抗NMDAR1亚单位IgG 葡萄球菌蛋白A 胶体金颗粒免疫标记复合物分子进行扫描,明确其特定的三维结构作为对照标准,然后扫描结合了免疫标记复合物分子的神经细胞膜表面,对表面形貌作出对比后确定目的抗原的定位和复合物三维结构。并与光镜、激光共聚焦、扫描电镜等方法进行对比。结果 在空白云母表面,免疫复合物分子在原子力显微镜下呈现出均匀分散粒径为49nm的特征性球形结构。在神经元表面结合免疫标记物后可以发现有大量的粒径为53nm的球形或双球形(短棒状)结构,颗粒均匀,截面为双峰或单峰。光镜下染色成片状结果,在共聚焦显微镜下荧光呈颗粒点状分布,扫描电镜结果为单个或结合颗粒,缺乏三维成像能力。结论 原子力显微镜下免疫胶体金标记技术可以在纳米尺度对目的膜受体蛋白进行定位和表面三维结构测定。NM- DA受体蛋白可以结合一个或两个胶体金复合物,与传统成像手段相比,原子力显微镜下胶体金标记方法可以对单个膜NMDA受体蛋白抗原进行定位、定性、定量标记测定。 展开更多
关键词 免疫复合物 受体蛋白 分子 N-甲基-D-天冬氨酸受体 纳米结构 神经元膜 AFM 细胞膜表面蛋白 蛋白A-胶体金 胶体金标记技术 显微镜下 免疫细胞化学 原子力显微镜 NMDAR1 NMDA受体 纳米尺度 三维结构 扫描电镜 神经细胞膜
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高师院校开展微格教学实验的研究 被引量:1
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作者 姚冬香 yao Dongxiang 《阜阳师范学院学报(自然科学版)》 2001年第3期63-65,共3页
微格教学是一种行之有效的提高学生教学技能的方法,如何改变目前高师院校微格教学的窘况,并就如何规范、有序地提高学生教学技能,本文提出了几点具体的参考意见,试图使微格教学实验课更上一层楼。
关键词 微格教学 教学技能 反馈 评估
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Systematic review and meta-analysis of prophylactic abdominal drainage after pancreatic resection 被引量:5
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作者 Chang-Wei Dou +11 位作者 Zhi-Kui Liu Yu-Li Jia Xin Zheng Kang-Sheng Tu Ying-Min yao Qing-Guang Liu 《World Journal of Gastroenterology》 SCIE CAS 2015年第18期5719-5734,共16页
AIM: To investigate whether prophylactic abdominal drainage is necessary after pancreatic resection. METHODS: Pub Med, Web of Science, and the Cochrane Library were systematically searched to obtain relevant articles ... AIM: To investigate whether prophylactic abdominal drainage is necessary after pancreatic resection. METHODS: Pub Med, Web of Science, and the Cochrane Library were systematically searched to obtain relevant articles published before January 2014. Publications were retrieved if they met the selection criteria. The outcomes of interest included: mortality, morbidity, postoperative pancreatic fistula(POPF), clinically relevant pancreatic fistula(CRPF), abdominal abscess, reoperation rate, the rate of interventional radiology drainage, and the length of hospital stay. Subgroup analyses were also performed for pancreaticoduodenectomy(PD) and for distal pancreatectomy. Begg's funnel plot and the Egger regression test were employed to assess potential publication bias.RESULTS: Nine eligible studies involving a total of 2794 patients were identified and included in this meta-analysis. Of the included patients, 1373 received prophylactic abdominal drainage. A fixedeffects model meta-analysis showed that placement of prophylactic drainage did not have beneficial effects on clinical outcomes, including morbidity, POPF, CRPF, reoperation, interventional radiology drainage, and length of hospital stay(Ps > 0.05). In addition, prophylactic drainage did not significantly increase the risk of abdominal abscess. Overall analysis showed that omitting prophylactic abdominal drainage resulted in higher mortality after pancreatectomy(OR = 1.56; 95%CI: 0.93-2.92). Subgroup analysis of PD showed similar results to those in the overall analysis. Elimination of prophylactic abdominal drainage after PD led to a significant increase in mortality(OR = 2.39; 95%CI: 1.22-4.69; P = 0.01).CONCLUSION: Prophylactic abdominal drainage after pancreatic resection is still necessary, though more evidence from randomized controlled trials assessing prophylactic drainage after PD and distal pancreatectomy are needed. 展开更多
关键词 PROPHYLACTIC ABDOMINAL drainage PANCREATIC RESECTION SYSTEMIC review META-ANALYSIS
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静止补偿器的非线性控制(英文) 被引量:2
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作者 Nicolas lLechevin +2 位作者 Ziwen yao 《电力系统自动化》 EI CSCD 北大核心 2001年第3期37-43,共7页
对于包含基于自换向绝缘双极型晶闸管 (IGBT)逆变器的静止补偿器 (STATCOM) ,提出了一种非线性控制策略。基于该控制策略 ,静止补偿器能够保证系统电压稳定在给定值附近 ,而且在提供无功补偿时具有理想的暂态性能。同时该控制策略具有... 对于包含基于自换向绝缘双极型晶闸管 (IGBT)逆变器的静止补偿器 (STATCOM) ,提出了一种非线性控制策略。基于该控制策略 ,静止补偿器能够保证系统电压稳定在给定值附近 ,而且在提供无功补偿时具有理想的暂态性能。同时该控制策略具有对主要参数扰动的鲁棒性。仿真和实验结果证实了该控制策略的有效性。 展开更多
关键词 无功功率 静止补偿器 非线性控制 渐近稳定 电压稳定 电力系统
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Three Perspectives of Granular Computing 被引量:20
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作者 Yiyu (Y.Y.) yao 《南昌工程学院学报》 CAS 2006年第2期16-21,共6页
As an emerging field of study, granular computing has received much attention. Many models, frameworks, methods and techniques have been proposed and studied. It is perhaps the time to seek for a general and unified v... As an emerging field of study, granular computing has received much attention. Many models, frameworks, methods and techniques have been proposed and studied. It is perhaps the time to seek for a general and unified view so that fundamental issues can be examined and clarified.This paper examines granular computing from three perspectives.By viewing granular computing as a way of structured thinking,we focus on its philosophical foundations in modeling human perception of the reality.By viewing granular computing as a method of structured problem solving,we examine its theoretical and methodological foundations in solving a wide range of real-world problems.By viewing granular computing as a paradigm of information processing,we turn our attention to its more concrete techniques. The three perspectives together offer a holistic view of granular computing. 展开更多
关键词 granular computing structured thinking structured problem solving information processing paradigm
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改造RADEON 9700 Pro的散热片
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作者 yao 《电脑》 2002年第12期58-58,共1页
关键词 显卡 散热片 技术改造 RADEON9700PRO
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EXISTENCE OF POSITIVE RADIAL SOLUTIONS FOR SOME SEMILINEAR ELLIPTIC EQUATIONS IN ANNULUS 被引量:2
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作者 yao Qing-liu(姚庆六) +1 位作者 MA Qin-sheng(马勤生) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第12期1452-1457,共6页
Applying Krasnosel'skii fixed point theorem of cone expansion-compression type, the existence of positive radial solutions for some second-order nonlinear elliptic equations in annular domains, subject to Dirichle... Applying Krasnosel'skii fixed point theorem of cone expansion-compression type, the existence of positive radial solutions for some second-order nonlinear elliptic equations in annular domains, subject to Dirichlet boundary conditions, is investigated. By considering the properties of nonlinear term on boundary closed intervals, several existence results of positive radial solutions are established. The main results are independent of superlinear growth and sublinear growth of nonlinear term. If nonlinear term has extreme values and satisfies suitable conditions, the main results are very effective. 展开更多
关键词 second-order elliptic equation annular domain positive radial solution
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Fault tolerant motion planning based on joint torque limit for redundant manipulators 被引量:2
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作者 赵京 yao Xuebin 《High Technology Letters》 EI CAS 2006年第1期72-76,共5页
First, two fault tolerant planning algorithms with avoidance of joint static torque limit or joint dynamic torque limit are proposed respectively. The former is suitable for the low-speed manipulators, and the latter ... First, two fault tolerant planning algorithms with avoidance of joint static torque limit or joint dynamic torque limit are proposed respectively. The former is suitable for the low-speed manipulators, and the latter is suitable for the high-speed manipulators. These algorithms not only can insure manipulation tasks to lie within the fault tolerant workspace but also can avoid joint torque limit, and hence can insure a redundant manipulator to be. fault tolerant in both kinematical sense and dynamic sense. Then, the simulation examples for a planar 3R manipulator demonstrate the validity of these algorithms. 展开更多
关键词 REDUNDANT MANIPULATOR joint torque limit fault tolerant planning
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Recent activity of Chihe segment of Tanlu fault zone 被引量:1
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作者 yao Da-quan(姚大全) +1 位作者 LIU Jia-can(刘加灿) 《Acta Seismologica Sinica(English Edition)》 CSCD 2004年第6期678-685,共9页
By means of differentiation of remote sensing image, field seismo-geological survey, analysis on drilling explora- tion materials, sampling and dating of rock samples, combined with seismicity and microscopic tectoni... By means of differentiation of remote sensing image, field seismo-geological survey, analysis on drilling explora- tion materials, sampling and dating of rock samples, combined with seismicity and microscopic tectonic analysis, this paper studies the recent activity of Chihe segment of the Tanlu fault zone. The result indicates that the Chihe fault segment undergoes the deformation alternately in the mode of stick slip and creep during Late Quaternary, and its recent activity is mainly creep. 展开更多
关键词 Tanlu fault zone Chihe segment structure resolution recent activity
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ISO9000 and the Quality Management System in the Digital Hospital 被引量:1
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作者 LIU Yalan(刘雅兰) +3 位作者 yao Bin(姚斌) ZHANG Zigang(张子刚) 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2002年第2期89-91,99,共4页
Summary: ISO9000 quality management system (ISO9000QMS) emphasize on the customer-oriented, managers' leadership and all staff's joining, adopt the process method and system management, spread the taking facts... Summary: ISO9000 quality management system (ISO9000QMS) emphasize on the customer-oriented, managers' leadership and all staff's joining, adopt the process method and system management, spread the taking facts as a basis to make decision and improve consistently, and establish win-win relation with the suppliers. So, the digital hospital can adopt the ISO9000QMS. In order to establish the ISO9000QMS, the digital hospital should: (1) Design integrally, including analyzing the operation procedure, clarifying the job duties, setting up the spreading team and setting the quality policy and objectives: (2) Learning the ISO9000 quality standards; (3) Drawing up the documents, including the quality manual, program files and operation guiding files; (4) Training according the documents; (5) Executing the quality standard, including the service quality auditing, quality record auditing and quality system auditing; (6) Improving continually. With the establishment of ISO900QMS, the digital hospital can appraise more accurately, analyze quality matters statistically and avoid the interference of artificial factors. 展开更多
关键词 ISO9000 quality management system digital hospital
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An Improved Multivariate T^2 Control Chart for Individual Observations in Low Volume Manufacturing 被引量:1
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作者 苗瑞 Wang +2 位作者 Dongpeng yao Yingxue 《High Technology Letters》 EI CAS 2004年第2期51-53,共3页
For multivariate statistical process quality control with individual observations, the usually recommended procedure is Hotelling's T2 control chart. Using the T2 statistic based on β distribution is an exact met... For multivariate statistical process quality control with individual observations, the usually recommended procedure is Hotelling's T2 control chart. Using the T2 statistic based on β distribution is an exact method for constructing multivariate control limits in low volume manufacturing, but it is not convenient in that the variation of sample size leads to a change in control limit. This paper presents an improved multivariate T2 control chart whose control limit does not change with sample size, which is especially useful when the sample size is small. 展开更多
关键词 多元统计控制 过程质量 低流量制造业 控制图表 控制限
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THE POSITIVE SOLUTION OF CLASSICAL GELFAND MODEL WITH COEFFICIENT THAT CHANGE SIGN
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作者 yao Qing-liu(姚庆六) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第12期1458-1463,共6页
The existence and iteration of positive solution for classical Gelfand models are considered, where the coefficient of nonlinear term is allowed to change sign in [0, 1]. By using the monotone iterative technique, an ... The existence and iteration of positive solution for classical Gelfand models are considered, where the coefficient of nonlinear term is allowed to change sign in [0, 1]. By using the monotone iterative technique, an existence theorem of positive solution is obtained, corresponding iterative process and convergence rate are given. This iterative process starts off with zero function, hence the process is simple, feasible and effective. 展开更多
关键词 Gelfand model coefficient changed sign positive solution EXISTENCE monotone iterative technique
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Effects of carbon dioxide pneumoperitoneum on metastasis of ovarian carcinoma cell line SKOV_3
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作者 唐均英 HUANG +2 位作者 Jin yao Zhen-wei 《Journal of Chongqing University》 CAS 2007年第1期8-13,共6页
The long suspicion of the potential harm of carbon dioxide (CO2) pneumoperitoneum exists in laparoscopic cancer surgery. For better understanding of this problem, we targeted this study at the effects of CO2 pneumop... The long suspicion of the potential harm of carbon dioxide (CO2) pneumoperitoneum exists in laparoscopic cancer surgery. For better understanding of this problem, we targeted this study at the effects of CO2 pneumoperitoneum on the invasive ability of ovarian carcinoma cell line and the possible mechanism within it. To study the effects of CO2 pneumoperitoneum on carcinoma cell, SKOV3 cells were divided into 2 groups, respectively exposed to pneumoperitoneal CO2-insuffiation and normal conditions. To study the possible mechanism, SKOV3 cells were divided into 3 groups, one was exposed to CO2 pneumoperitoneum, one to N2 and the other to normal conditions served as control. The in vitro adhesive and invasive ability of the cells was analyzed through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay and Boyden filters metastasis model; the expressions of vascular endothelial growth factor C (VEGF-C) and matrix metalloproteinase 9 (MMP9) were determined by reverse transcription polymerase chain reaction(RT-PCR), and Western blot. We found that the adhesive ratio of SKOV3 cells exposed to CO2 was significantly higher than that of the control group; cells exposed to CO2 invaded the matrigel with a greater number (P〈0.01); the expression of VEGF-C exposed to both CO2 and N2 was significantly increased compared with control group (P〈0.05); the MMP9 expression level of CO2 group was higher than that of N2 group, P〈0.05. We concluded that carbon dioxide pneumoperitoneum may improve the adhesive and invasive ability of ovarian carcinoma cell line in vitro and CO2 can also be an independent factor to stimulate the expression of MMP9. 展开更多
关键词 carbon dioxide PNEUMOPERITONEUM ovarian carcinoma matrix metalloproteinase 9 (MMP9) vascular endothelial growth factor C (VEGF-C)
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北大巴山逆冲推覆带鲁家坪组泥板岩微孔隙结构表征
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作者 田涛 付德亮 +2 位作者 段中会 姚建明 杨甫 《煤炭科学技术》 CAS CSCD 北大核心 2021年第6期225-234,共10页
北大巴山逆冲推覆带发育大量富有机质泥板岩,为研究该区极浅变质泥板岩的微观孔隙结构,通过低温氮气物理吸附、高压压汞、氩离子抛光-场发射扫描电镜(Ar-FESEM)、X-射线衍射(XRD)等试验,定量、定性表征下寒武统鲁家坪组富有机质泥板岩... 北大巴山逆冲推覆带发育大量富有机质泥板岩,为研究该区极浅变质泥板岩的微观孔隙结构,通过低温氮气物理吸附、高压压汞、氩离子抛光-场发射扫描电镜(Ar-FESEM)、X-射线衍射(XRD)等试验,定量、定性表征下寒武统鲁家坪组富有机质泥板岩微观孔隙结构特征和影响因素。试验结果表明,鲁家坪组泥板岩微观孔隙结构具有强烈的非均质性,孔径范围分布广且组合形式多样。紫阳地区鲁家坪组泥板岩的微孔、介孔、大孔发育程度相当或更偏向于介孔-大孔;岚皋地区以微孔发育为主导,辅以发育介孔和大孔。鲁家坪组泥板岩孔隙大小和类型与岩石矿物组分密切相关,石英、长石、碳酸盐岩等脆性矿物相关孔隙类型以粒内溶蚀孔、边缘孔缝、粒间孔为主且多被黏土矿物、有机质充填,脆性矿物颗粒挤压黏土矿物和有机质内部微孔、介孔,致使其改造甚至是闭合,约束孔隙体积发育;黏土矿物相关孔隙类型以层间孔缝为主,孔径大小以介孔为主,是提升鲁家坪组孔隙体积的主要孔隙类型;有机质孔是鲁家坪组微孔孔隙主要类型,提供了大量比表面积,是气体吸附的主要场所。鲁家坪组泥板岩的微观孔隙结构利于天然气吸附保存,但总体孔喉细小、连通性较差,不利于游离气运移。 展开更多
关键词 浅变质泥板岩 微观孔隙结构 氮气吸附 高压压汞
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THEORETICAL MODEL OF VIBRATING OBJECT TRANSMITTING NOISE TOWARDS EXTERNAL SOUND
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作者 yao Zhi-yuan(姚志远) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第3期350-354,共5页
On the basic theory of modal method, the coupling relation between the vibration of objects and external sound was analyzed, the theoretical model solving the vibration and noise was provided, the corresponding calcul... On the basic theory of modal method, the coupling relation between the vibration of objects and external sound was analyzed, the theoretical model solving the vibration and noise was provided, the corresponding calculation formula was given. The calculating results show out that this calculation formula is correct. 展开更多
关键词 noise control acoustic radiation inverse problem
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Study on the Relation between the Drape of Fabrics and Its Revolving Speed
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作者 xu Jun(徐军) +1 位作者 yao Mu(姚穆) 《Journal of Donghua University(English Edition)》 EI CAS 2001年第2期127-129,共3页
Based on the tests of eight kinds of typical fabrics, the relation between the drape coefficient of different fabrics and its revolving speed was analyzed and discussed. The result of regression curve fitting of exper... Based on the tests of eight kinds of typical fabrics, the relation between the drape coefficient of different fabrics and its revolving speed was analyzed and discussed. The result of regression curve fitting of experimental data showed that the relation between drape coefficient of fabric and its revolving speed could be expressed by negative exponential equation. Meanwhile, the difference of drape coefficients between static and dynamic at 100 ~ 150r.p.m was suggested to be one of the expressing parameters of the lively degree of fabric dynamic drape. 展开更多
关键词 DRAPE coefficient revolving speed DYNAMIC drape.
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One Functioning Pattern to Introduce International Matured Underwear Brands into China's Market
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作者 yao Bing(姚冰) +1 位作者 Jiang Zhiwei(蒋智威) 《Journal of Donghua University(English Edition)》 EI CAS 2001年第3期94-96,共3页
China's underwear market, concurrently with the transformation of China's fashion companies' structure performed in recent years, has attracted numerous underwear brands to share the large but limited mark... China's underwear market, concurrently with the transformation of China's fashion companies' structure performed in recent years, has attracted numerous underwear brands to share the large but limited market,especially after entering WTO. Confronting the sharp competition, how can the China's companies survive?The following study answers this urgent question by introducing one functioning pattern for international matured brands to spread in the China's market. 展开更多
关键词 underwear brand China's market.
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Evidence for Base Substitutions and Repair of DNA Mismatch Damage Induced by Low Energy N^+ Ion Beam Implantation in E. coli
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作者 谢传晓 Guo +6 位作者 Jinhua yao Jianmin Wu Lijun Yu Zengliang 《High Technology Letters》 EI CAS 2003年第2期1-6,共6页
Ever since the low energy N + ion beam has been accepted, the mutations of ionizing radiation are attributable mainly to avoidance of DNA damages repair. Evidences based on in vivo proof results are limited. Using the... Ever since the low energy N + ion beam has been accepted, the mutations of ionizing radiation are attributable mainly to avoidance of DNA damages repair. Evidences based on in vivo proof results are limited. Using the E.coli wild type and mutator strains, the mutant frequencies suggest that base substitutions in rpoB gene are induced by the N + implantation. A highly conserved region is selected to get the direct evidence for base substitutions by sequence of the high fidelity PCR amplification products in mutants. Most of the mutants (90.9%, 40/44) have at least one base substitution in the amplification region. The evidences for CG to TA (55%, 22/40), AT to GC (20%, 8/40) and TA to CG (5%, 2/40) transitions are identified. The transversions are AT to TA (15%, 6/40) and GC to CG (5%, 2/40). It is suggested that DNA cytosine methylase might play an important role in mismatch repair of DNA damage induced by N + implantation by analysis of the mutant frequencies of mutator strains. 展开更多
关键词 low energy N + ion beam base substitutions mismatch repair mutator strains
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