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预成型标线和热熔标线路用性能及环保性对比
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作者 彭一川 房珂馨 程乐怡 《黑龙江交通科技》 2023年第3期19-22,共4页
道路标线的路用性能和环保性是标线的重要性能,为了给标线选择时提供参考,对预成型标线和热熔标线进行了路用性能对比实验,并采用层次分析法对二者的环保性能进行综合评价。结果表明:通过浸泡实验证明该预成型标线能够满足耐水性以及耐... 道路标线的路用性能和环保性是标线的重要性能,为了给标线选择时提供参考,对预成型标线和热熔标线进行了路用性能对比实验,并采用层次分析法对二者的环保性能进行综合评价。结果表明:通过浸泡实验证明该预成型标线能够满足耐水性以及耐碱性要求;通过构造深度以及摆式仪实验,得到黄色、白色预成型标线、热熔标线的平均抗滑值BPN分别为98、98、78.2,将结果与规定要求长效标线带A、B级抗滑的最小抗滑值对比,看出该预成型标线的抗滑性满足要求,且优于热熔标线;通过自动车辙实验,比较每次实验的标线磨耗量,发现预成型标线的耐磨性优于热熔标线,且与标线耐磨性标准相比,预成型标线符合标准规范要求。研究还发现预成型标线不管在重金属、二氧化碳排放、粉尘及噪声污染哪个方面,相较于热熔标线的优越性都非常显著。预成型标线的路用性能和环保性能相比于热熔标线都有显著的优势,因此在进行标线施划时应考虑采用预成型标线的可能性。 展开更多
关键词 成型线 热熔线 路用性能 环保性 层次分析法
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预成型标线带与热熔型标线的路用价值对比分析
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作者 刘华 《西部交通科技》 2023年第8期43-44,91,共3页
文章对A380AW预成型标线带和热熔型涂料标线在高速公路的路用价值开展了对比试验,以光度性能为主要比对依据,经定期检测记录及变化趋势分析,得出研究结论:预成型标线带各项性能均优于热熔型涂料标线,能在全天候(干燥、湿润、连续降雨)... 文章对A380AW预成型标线带和热熔型涂料标线在高速公路的路用价值开展了对比试验,以光度性能为主要比对依据,经定期检测记录及变化趋势分析,得出研究结论:预成型标线带各项性能均优于热熔型涂料标线,能在全天候(干燥、湿润、连续降雨)条件下长期维持高逆反射亮度系数,耐候性能优异,夜间或者雨夜边界视认效果清晰明亮,但与热熔型涂料标线相比,预成型标线带的造价较高,无法大面积应用于高速公路;热熔型涂料标线以其经济性优势,仍是高速公路使用的主流标线类型。 展开更多
关键词 成型线带 热熔型线 光度性能 线寿命
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道路预成形标线带路面粘结性能的评价分析 被引量:6
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作者 黄晚清 游宏 陆阳 《武汉理工大学学报(交通科学与工程版)》 2017年第4期599-603,共5页
以三种道路预成型标线带的剥离试验,研究路面类型、构造深度、湿度和温度对标线带粘结性能的影响.测试发现,标线带的粘结性能随路面构造深度的增加而下降,粘结于沥青路面的降幅相对较小;在相同构造深度下,标线带与沥青路面的粘结性大于... 以三种道路预成型标线带的剥离试验,研究路面类型、构造深度、湿度和温度对标线带粘结性能的影响.测试发现,标线带的粘结性能随路面构造深度的增加而下降,粘结于沥青路面的降幅相对较小;在相同构造深度下,标线带与沥青路面的粘结性大于与水泥混凝土路面的粘结性;标线带使用过程中具有优良的封水作用,但在施工过程中的路面潮湿会严重降低其粘结性能;测试数据同时表明,标线带与两类路面的粘结性均显示出较强的温度敏感性.由此认为,预成形标线带的剥离试验,应充分考虑路面材料、构造深度及试验温度,以对标线带粘结性能做出符合实际的评价. 展开更多
关键词 成形线带 剥离试验 粘结性 路面类型 路表特性 温湿度
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道路预成形标线带检测技术 被引量:3
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作者 苏文英 白媛媛 吴凡 《公路交通科技》 CAS CSCD 北大核心 2005年第10期129-131,150,共4页
对道路预成形标线带检测技术,包括检测标准、产品分类、测试条件和技术要求等,结合国外先进标准进行分析研究。重点介绍在编写其检测标准时,对物理性能、色度性能、逆反射性能、耐水性能、耐碱性能、耐磨性能、粘结性能、抗滑性能等各... 对道路预成形标线带检测技术,包括检测标准、产品分类、测试条件和技术要求等,结合国外先进标准进行分析研究。重点介绍在编写其检测标准时,对物理性能、色度性能、逆反射性能、耐水性能、耐碱性能、耐磨性能、粘结性能、抗滑性能等各项技术指标,参考国外先进标准和国内实际情况进行研究确定的过程,指导对国内标线带的产品检测和质量控制。 展开更多
关键词 成形线带 交通线 检测 技术要求
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内嵌式预成型标线带应用的可行性研究 被引量:2
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作者 刘勇 《公路交通技术》 2022年第2期151-155,162,共6页
结合广州市环市东路品质提升项目,对内嵌式预成型标线带应用的综合成本、施工效率、环保及职业健康、耐久性等方面与涂料型标线进行了对比分析。结果表明:1)内嵌式预成型标线带缩短了因路面施工而导致的交通拥堵,综合效益成本更低;2)初... 结合广州市环市东路品质提升项目,对内嵌式预成型标线带应用的综合成本、施工效率、环保及职业健康、耐久性等方面与涂料型标线进行了对比分析。结果表明:1)内嵌式预成型标线带缩短了因路面施工而导致的交通拥堵,综合效益成本更低;2)初始反光亮度高,提高了夜间驾驶者的可视距离,提升了夜间行车安全;3)施工过程中无VOC排放,减少了对沿线居民生活环境的污染;4)几乎与沥青路面同等寿命,在沥青路面使用寿命周期中,避免了中途多次的重复施划。结论是在公路和城市重点路段路面翻新工程中,内嵌式预成型标线带应用可行,具有工程应用推广价值。 展开更多
关键词 成型线带 内嵌式 耐久性 逆反射系数
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道路预成形标线视认性能研究 被引量:1
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作者 程乐怡 彭一川 房珂馨 《交通与运输》 2022年第4期78-83,共6页
为了给道路交通标线的设计与应用提供参考,提高道路安全性,减少交通事故发生概率,探索不同条件下预成形标线和传统热熔标线的视认性能,进行交通标线视认性能的驾驶试验研究。设计不同光照强度、天气等条件下的多种实验场景,采用方差分... 为了给道路交通标线的设计与应用提供参考,提高道路安全性,减少交通事故发生概率,探索不同条件下预成形标线和传统热熔标线的视认性能,进行交通标线视认性能的驾驶试验研究。设计不同光照强度、天气等条件下的多种实验场景,采用方差分析研究各个因素对标线视认距离影响的显著性及其交互作用。结果表明,在白天亮度较高条件下,白色热熔标线和黄色预成形标线对于视认距离无显著影响;在晚上亮度较低的条件下,对比热熔标线,预成形标线在视认距离上有很大提升。在晴天、雨天条件下,预成形标线对比热熔标线在视认距离上都有很大提升,其中白色预成形标线在雨天条件下的效果最好。试验结果显示,不同因素影响下,预成形标线的视认性能要明显强于传统热熔标线。 展开更多
关键词 视认性能 成形线 方差分析 视认距离 热熔线
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预成形标线带在高速公路上的应用研究 被引量:2
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作者 李春玲 《浙江交通职业技术学院学报》 CAS 2014年第4期1-6,共6页
本为改善涂料标线的缺陷,专家研发了一种新型的道路预成形标线带。预成形标线带除具有常规标线的性能之外,还具有耐磨、防滑、施工简便等优点,在发达国家已被广泛使用。通过对德国某预成形标线带的主要技术参数逆反射亮度系数、抗滑值... 本为改善涂料标线的缺陷,专家研发了一种新型的道路预成形标线带。预成形标线带除具有常规标线的性能之外,还具有耐磨、防滑、施工简便等优点,在发达国家已被广泛使用。通过对德国某预成形标线带的主要技术参数逆反射亮度系数、抗滑值在高速公路上的变化趋势分析,以及与同期铺设的热熔标线的比较,得出以下结论:预成形标线的性能明显好于热熔标线,且施工方便,但其对路面的要求比较高,在旧路面上使用后其逆反射亮度系数下降得比较快,且其昂贵的价格使得其又不能大量使用。 展开更多
关键词 成形线 热熔线 逆反射亮度系数 抗滑性能 分析
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工业控制机系统调试预算的编制
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作者 李伟 吴波 《沈阳建筑工程学院学报》 1997年第3期287-289,共3页
论述工业控制机系统调试预算的编制要点,并详细介绍准确计算工程量的方法。
关键词 系统调试 计算机 调试 预标定额 建筑工程
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电感耦合等离子体发射光谱法同时测定土壤样品中的硼、磷、钠、钾的方法研究 被引量:3
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作者 黄浩 武明丽 《分析测试技术与仪器》 CAS 2024年第1期47-52,共6页
土壤样品中的硼元素在酸溶体系中易挥发,采用碱熔法则无法同时测定钾、钠,并且大量的盐类也不利于检测.而在盐酸-氢氟酸-硝酸三酸体系中,通过加入甘露醇可以保护硼在密闭消解条件下不易挥发损失.以电感耦合等离子体发射光谱法(ICP-OES)... 土壤样品中的硼元素在酸溶体系中易挥发,采用碱熔法则无法同时测定钾、钠,并且大量的盐类也不利于检测.而在盐酸-氢氟酸-硝酸三酸体系中,通过加入甘露醇可以保护硼在密闭消解条件下不易挥发损失.以电感耦合等离子体发射光谱法(ICP-OES)为测试手段,使用耐氢氟酸进样系统,可以有效避免待测元素受到污染,通过预加内标的方法来纠正体积偏差后,可以实现对土壤样品中硼、磷、钠、钾元素的同时测定.试验结果表明,在没有加稳定剂时,硼在消解过程中会因挥发而损失严重,但在有稳定剂的存在下,即使在160℃以上,硼也没有检测到挥发损失,证明采用甘露醇作为稳定剂是可行的.通过有证土壤和水系沉积物标准样品的测试验证,对于硼质量分数高于10mg/kg的土壤样品,其测试结果与认定值相对偏差小于10%,具有很好的灵敏度且操作简单,易用于大批量的检测任务. 展开更多
关键词 甘露醇稳定剂 ICP-OES 耐氢氟酸进样系统 加内
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Improved AVOA based on LSSVM for wind power prediction
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作者 ZHANG Zhonglin WEI Fan +1 位作者 YAN Guanghui MA Haiyun 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2024年第3期344-359,共16页
Improving the prediction accuracy of wind power is an effective means to reduce the impact of wind power on power grid.Therefore,we proposed an improved African vulture optimization algorithm(AVOA)to realize the predi... Improving the prediction accuracy of wind power is an effective means to reduce the impact of wind power on power grid.Therefore,we proposed an improved African vulture optimization algorithm(AVOA)to realize the prediction model of multi-objective optimization least squares support vector machine(LSSVM).Firstly,the original wind power time series was decomposed into a certain number of intrinsic modal components(IMFs)using variational modal decomposition(VMD).Secondly,random numbers in population initialization were replaced by Tent chaotic mapping,multi-objective LSSVM optimization was introduced by AVOA improved by elitist non-dominated sorting and crowding operator,and then each component was predicted.Finally,Tent multi-objective AVOA-LSSVM(TMOALSSVM)method was used to sum each component to obtain the final prediction result.The simulation results show that the improved AVOA based on Tent chaotic mapping,the improved non-dominated sorting algorithm with elite strategy,and the improved crowding operator are the optimal models for single-objective and multi-objective prediction.Among them,TMOALSSVM model has the smallest average error of stroke power values in four seasons,which are 0.0694,0.0545 and 0.0211,respectively.The average value of DS statistics in the four seasons is 0.9902,and the statistical value is the largest.The proposed model effectively predicts four seasons of wind power values on lateral and longitudinal precision,and faster and more accurately finds the optimal solution on the current solution space sets,which proves that the method has a certain scientific significance in the development of wind power prediction technology. 展开更多
关键词 African vulture optimization algorithm(AVOA) least squares support vector machine(LSSVM) variational mode decomposition(VMD) multi-objective prediction wind power
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排水铸铁管及存水弯工程量计算的一些问题的探讨
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作者 高振生 《西北建筑工程学院学报(自然科学版)》 1999年第4期49-51,58,共4页
依据暖卫施工规范、全国统一安装工程预算定额及工程量计算规则的规定,针对建筑给排水工程量计算的一些问题,给出了工程量计算优化的原则、铸铁管及存水弯的除锈刷油工程量计算表,并指出了预算定额中工程量计算表的一些数据的错误.
关键词 工程量 排水 铸铁管 存水变 计算表 预标
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Targets Track Predicting of IR Image by CMAC 被引量:2
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作者 史彩成 赵保军 +1 位作者 毛二可 何佩琨 《Journal of Beijing Institute of Technology》 EI CAS 2002年第3期263-265,共3页
The centroid and attitude of target must be predicted in target tracking of IR image for increasing capture probability. CMAC estimator can effectually resolve conflict between operational counts and predicting preci... The centroid and attitude of target must be predicted in target tracking of IR image for increasing capture probability. CMAC estimator can effectually resolve conflict between operational counts and predicting precision. CMAC estimator is trained with a linear model, then the centroid and attitude are predicted. It is trained once by actual error in each frame to reduce the estimate error. CMAC has excellent predicting precision and small operational counts, it adapts to real time processing for target tracking. The experimental results show that CMAC can accurately estimate the centroid and attitude of target. It adapts to change of model and has robustness. 展开更多
关键词 IR image CMAC target tracking
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Comparative Study on the Dwarfing Pre-selected Indices of Pear Germplasms with Different Growth Potentials
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作者 徐颖 曹后男 +2 位作者 宗成文 巩艳明 朴永虎 《Agricultural Science & Technology》 CAS 2009年第6期108-110,143,共4页
[ Objective] The aim of this study was to provide a theoretical basis for breeding selection, matching parents and the identification of traits during early period. [ Method ] With Shanli ( Pyrus ussuriensis Maxim) ... [ Objective] The aim of this study was to provide a theoretical basis for breeding selection, matching parents and the identification of traits during early period. [ Method ] With Shanli ( Pyrus ussuriensis Maxim) , S2 × Shanli (vigorous), S2 x ShanU (dwarfing), S2, super-dwarfing germplasm as the matedais, the dwarfing traits of each germplasm were identified by indices including leaf stomata density, branch-cortex ratio, leaf thickness, palisade tissue thickness, paisade-spongy ratio and vessel density. [Result] Among five kinds of pear germplasms, Shanli with strong growth potential had the smallest branch-cortex ratio, leaf thickness, palisade tissue thickness and palisade-spengy ratio, but the largest stomata density and vessel density. On the contrary, super-dwarfing germplasm with weak growth potential had the largest branch-cortex ratio, leaf thickness, palisade tissue thickness and palisade-spongy ratio, but the smallest stomata density and vessel density. There was a difference in stomata density, branch-cortex ratio, leaf thickness, palisade tissue thickness, palisade-spongy ratio and vessel density for every germplasm. [ Conclusion] Stomata density, branch-cortex ratio, leaf thickness, palisade tissue thickness, palisade-spongy ratio and vessel density can be used as indices of identification for pear growth potential in early period. 展开更多
关键词 PEAR DWARFING Pre-selected indices
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Analysis of Physical Quantities and Radar Parameters about Hail Shooting and Heavy Convective Rainfall
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作者 陈金敏 刁秀广 《Agricultural Science & Technology》 CAS 2012年第11期2434-2437,2441,共5页
[Objective] The paper is to analyze physical quantities and radar parameter of hail shooting and heavy convective rainfall weather. [Method] Using radar data of Jinan station during 2002 and 2008, combined with soundi... [Objective] The paper is to analyze physical quantities and radar parameter of hail shooting and heavy convective rainfall weather. [Method] Using radar data of Jinan station during 2002 and 2008, combined with sounding data, the physical quantities and radar parameter of hail shooting and heavy convective rainfall weather are compared and analyzed. [Result] The smaller Sl is conducive to the generation of hail weather. When K〉 35 ~C, the probability for occurrence of heavy rainfall weather is significantly increased; when K〈20 ^(3, the probability for occurrence of heavy rainfall weather is significantly decreased. When CAPE value is greater than 1 500 J/KG, the probability for occurrence of hail weather is significantly decreased, while the probability for occurrence of heavy rainfall weather is significantly in- creased. The possibility for occurrence of hail monomer is small when the wind shear is less than 5 m/s; and it is large while wind shear is greater than 20 m/s. The radar forecasting indexes of hail monomer is as follows: VIL value reaches 35 kg/m2 (May), 43 kg/m2 (June and July), the monomer height is greater than 9 km, the maximum reflectivity factor is larger than 60 dBz, strong center height reaches 3.3 km (May), 4.3 km (June) and 5.5 km (July); VlL value of heavy rainfall monomer generally is below 25 kg/m2. [Conclusion] The paper provides basis form prediction of hail and heavy rainfall. 展开更多
关键词 HAIL Heavy convective rainfall VIL Weather radar parameter
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小学数学课堂采用“七步教学模式”后的感悟
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作者 钟光莲 《学周刊(中旬)》 2014年第8期101-101,共1页
在全面推进素质教育的进程中,学生的主体地位越来越受到人们的普遍重视。在这一形势下,笔者对当前的教学模式进行了改革与深化,在小学数学课堂中践行了"七步教学模式",并取得了一些成效,在此撰文以飨同仁。
关键词 教学模式 预标
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The Prognostic Value of Pathological and Molecular Margins Marked by p53 and eIF4E in Laryngeal Carcinoma
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作者 夏良平 曾剑 +3 位作者 郭朱明 饶慧兰 曾敬 曾宗渊 《The Chinese-German Journal of Clinical Oncology》 CAS 2005年第1期56-60,69,共6页
Objective: To study the prognostic value of the pathological margin and molecular margin marked by eIF4E and P53 protein in laryngeal carcinoma. Methods: The prognostic value of pathological and molecular margin was s... Objective: To study the prognostic value of the pathological margin and molecular margin marked by eIF4E and P53 protein in laryngeal carcinoma. Methods: The prognostic value of pathological and molecular margin was studied in 253 cases and 67 cases respectively, the latter were pathological negative margin chosen from the former. Immunohistochemisty was used to detect the expression of eIF4E and p53 proteins. Results: The rate of pathological, p53 and eIF4E positive margins was 20.2%, 19.4% and 32.8% respectively. The recurrent rate of those with positive margins was higher than that of negative margins, which including pathological margin (70.6% vs 35.1%, P =0.0000), p53 margin (69.2% vs 33.3%, P =0.018) and eIF4E margin (63.6% vs 28.9%, P =0.018); The survival rate of those with negative margins was higher than those with positive margins, including pathological margin (the 5-year cumulative survival rate was 37.52% and 64.37% respectively, P =0.0023), p53 margin (the 5-year cumulative survival rate was 24.62% and 75.69% respectively, P =0.0012) and eIF4E margin (the 5-year cumulative survival rate was 43.31% and 77.52% respectively, P =0.0006). Conclusion: The prognosis of those with both pathological and molecular positive margins was worse than that of the negative margins; Both the eIF4E and p53 were useful markers to pick out the poor prognostic patients from those with pathological negative margin, and the former seemed to be more potential. 展开更多
关键词 laryngeal neoplasm/squamous cell carcinoma PROGNOSIS molecular margin eukaryotic translation initiation factor 4E P53
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Benchmarking of energy efficiency standards for residential buildings in China
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作者 陈华 李慧玲 《Journal of Southeast University(English Edition)》 EI CAS 2010年第2期151-155,共5页
In order to benchmark the energy efficiency standards for residential buildings in China,the Hong Kong building environment assessment method(HK-BEAM)is chosen as the compliance criteria for assessment.The annual en... In order to benchmark the energy efficiency standards for residential buildings in China,the Hong Kong building environment assessment method(HK-BEAM)is chosen as the compliance criteria for assessment.The annual energy consumption and the overall thermal transfer value(OTTV)of a baseline residential building prescribed in the Chinese codes and the HK-BEAM are evaluated and compared by the energy budget approach.The results show that in the Chinese codes,the OTTV of the residential building is lower,but the annual energy consumption and the cooling load are higher than those in the HK-BEAM.The annual energy use difference amounts to 13.4%.All the compliance criteria except the ventilation rate and the equipment power in the Chinese codes are set higher than those in the HK-BEAM.However,the compliance criteria of the ventilation rate and the equipment power,especially the ventilation rate,result in much energy consumption,which ultimately induces a high energy budget for residential buildings. 展开更多
关键词 Chinese energy efficiency code Hong Kong building environment assessment method(HK-BEAM) energy budget approach residential buildings
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P53 immunohistochemical scoring:an independent prognostic marker for patients after hepatocellular carcinoma resection 被引量:18
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作者 Lun-Xiu Qin Zhao-You Tang Zeng-Chen Ma Zhi-Quan Wu Xin-Da Zhou Qing-Hai Ye Yuan Ji Li-Wen Huang Hu-Liang Jia Hui-Chuan Sun Lu Wang,Liver Cancer Institute and Zhongshan Hospital,Fudan University,Shanghai,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2002年第3期459-463,共5页
AIM: To confirm if p53 mutation could be a routine predictive marker for the prognosis of hepatocellular carcinoma (HCC) patients. METHODS: Two hundreds and forty-four formalin-fixed paraffin-embedded tumor samples of... AIM: To confirm if p53 mutation could be a routine predictive marker for the prognosis of hepatocellular carcinoma (HCC) patients. METHODS: Two hundreds and forty-four formalin-fixed paraffin-embedded tumor samples of the patients with HCC receiving liver resection were detected for nuclear accumulation of p53. The percent of P53 immunoreactive tumor cells was scored as 0 to 3+ in P53 positive region (【10% -, 10-30% +, 31-50% ++, 】50% +++). Proliferating cell nuclear antigen (PCNA) and some clinicopathological characteristics, including patients' sex, preoperative serum AFP level, tumor size, capsule, vascular invasion (both visual and microscopic), and Edmondson grade were also evaluated. RESULTS: In univariate COX harzard regression model analysis, tumor size, capsule status, vascular invasion, and p53 expression were independent factors that were closely related to the overall survival (OS) rates of HCC patients. The survival rates of patients with 3+ for P53 expression were much lower than those with 2+ or + for P53 expression. Only vascular invasion (P【0.05) and capsule (P【0.01) were closely related to the disease-free survival (DFS) of HCC patients. In multivariate analysis, p53 overexpression (RI 0.5456, P【0.01) was the most significant factor associated with the OS rates of patients after HCC resection, while tumor size (RI 0.5209, P【0.01), vascular invasion (RI 0.5271, P【0.01) and capsule (RI-0.8691, P【0.01) were also related to the OS. However, only tumor capsular status was an independent predictive factor (P【0.05) for the DFS. No significant prognostic value was found in PCNA-LI, Edmondson's grade, patients' sex and preoperative serum AFP level. CONCLUSION: Accumulation of p53 expression, as well as tumor size, capsule and vascular invasion, could be valuable markers for predicting the prognosis of HCC patients after resection. The quantitative immunohistochemical scoring for P53 nuclear accumulation might be more valuable for predicting prognosis of patients after HCC resection than the common qualitative analysis. 展开更多
关键词 ADOLESCENT Adult Aged Carcinoma Hepatocellular Female Genes p53 Humans Immunohistochemistry Liver Neoplasms Male Middle Aged Mutation Prognosis Research Support Non-U.S. Gov't Tumor Markers Biological Tumor Suppressor Protein p53
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The prognostic molecular markers in hepatocellular carcinoma 被引量:163
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作者 Lun-Xiu Qin Zhao-You Tang,Liver Cancer Institute and Zhongshan Hospital,Fudan University,Shanghai,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2002年第3期385-392,共8页
The prognosis of hepatocellular carcinoma (HCC) still remains dismal, although many advances in its clinical study have been made. It is important for tumor control to identify the factors that predispose patients to ... The prognosis of hepatocellular carcinoma (HCC) still remains dismal, although many advances in its clinical study have been made. It is important for tumor control to identify the factors that predispose patients to death. With new discoveries in cancer biology, the pathological and biological prognostic factors of HCC have been studied quite extensively. Analyzing molecular markers (biomarkers) with prognostic significance is a complementary method. A large number of molecular factors have been shown to associate with the invasiveness of HCC, and have potential prognostic significance. One important aspect is the analysis of molecular markers for the cellular malignancy phenotype. These include alterations in DNA ploidy, cellular proliferation markers (PCNA, Ki-67, Mcm2, MIB1, MIA, and CSE1L/CAS protein), nuclear morphology, the p53 gene and its related molecule MD M2, other cell cycle regulators (cyclin A, cyclin D, cyclin E, cdc2, p27, p73), oncogenes and their receptors (such as ras, c-myc, c-fms, HGF, c-met, and erb-B receptor family members), apoptosis related factors (Fas and FasL), as well as telomerase activity. Another important aspect is the analysis of molecular markers involved in the process of cancer invasion and metastasis. Adhesion molecules (E-cadherin, catenins, serum intercellular adhesion molecule-1, CD44 variants), proteinases involved in the degradation of extracellular matrix (MMP-2, MMP-9, uPA, uPAR, PAI), as well as other molecules have been regarded as biomarkers for the malignant phenotype of HCC, and are related to prognosis and therapeutic outcomes. Tumor angiogenesis is critical to both the growth and metastasis of cancers including HCC, and has drawn much attention in recent years. Many angiogenesis-related markers, such as vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), platelet-derived endothelial cell growth factor (PD-ECGF), thrombospondin (TSP), angiogenin, pleiotrophin, and endostatin (ES) levels, as well as intratumor microvessel density (MVD) have been evaluated and found to be of prognostic significance. Body fluid (particularly blood and urinary) testing for biomarkers is easily accessible and useful in clinical patients. The prognostic significance of circulating DNA in plasma or serum, and its genetic alterations in HCC are other important trends. More attention should be paid to these two areas in future. As the progress of the human genome project advances, so does a clearer understanding of tumor biology, and more and more new prognostic markers with high sensitivity and specificity will be found and used in clinical assays. However, the combination of some items, i.e., the pathological features and some biomarkers mentioned above, seems to be more practical for now. 展开更多
关键词 Apoptosis CARCINOGENS Carcinoma Hepatocellular Cell Adhesion Cell Division Cell Nucleus Extracellular Matrix Genes p53 Humans Liver Neoplasms Neovascularization Pathologic PLOIDIES Prognosis Proteome TELOMERASE Tumor Markers Biological
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Alpha-fetoprotein expression is a potential prognostic marker in hepatocellular carcinoma 被引量:6
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作者 Dénes Grg János Regly-Mérei +2 位作者 Sándor Paku László Kopper Péter Nagy 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第32期5015-5018,共4页
AIM: To characterize the alpha-fetoprotein (AFP) positive and negative hepatocellular carcinoma (HCC) samples. METHODS: Thirty-seven paraffin-embedded human HCC samples were analyzed by immunohistochemistry for ... AIM: To characterize the alpha-fetoprotein (AFP) positive and negative hepatocellular carcinoma (HCC) samples. METHODS: Thirty-seven paraffin-embedded human HCC samples were analyzed by immunohistochemistry for the following antigens: AFP,β-catenin, p53, CD44, MSH-2, MLH-1, and HNF-4. The tumors were divided into two groups based on the AFP expression. The immunophenotypic data and important clinical parameters were studied between the two groups. RESULTS: Twenty-one of the thirty-seven examined HCCs were AFP positive. Seven with nudear p53 staining were AFP positive, while seven tumors with nuclear β-catenin staining were AFP negative. CD44 staining and high histological tumor grade were more frequent among the AFP-positive HCCs. The other immunophenotypical and dinical parameters did not show statistically significant difference in their distribution between the AFP positive and negative samples. CONCLUSION: AFP expression in HCC correlates with unfavorable prognostic factors, while nuclear β-catenin positivity is more common among the AFP-negative liver tumors. This observation supports the microarray data on in vivo human tumors. 展开更多
关键词 Hepatocellular carcinoma ALPHA-FETOPROTEIN P53 Β-CATENIN CD44
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