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乙型肝炎病毒开放编码区T53C、G912A突变的临床意义
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作者 郑小勤 陈玉涵 +2 位作者 张鑫 陈德喜 丁惠国 《北京医学》 CAS 2017年第12期1201-1204,1208共5页
目的探讨HBV DNA开放编码区T53C、G912A突变的临床意义。方法 2004-2006年留存血清标本的慢性HBV感染患者112例,其中慢性乙型肝炎(CHB)69例(61.6%),乙肝肝硬化(LC)37例(33.0%),乙肝相关肝癌(HCC)6例(5.4%)。所有血清标本均... 目的探讨HBV DNA开放编码区T53C、G912A突变的临床意义。方法 2004-2006年留存血清标本的慢性HBV感染患者112例,其中慢性乙型肝炎(CHB)69例(61.6%),乙肝肝硬化(LC)37例(33.0%),乙肝相关肝癌(HCC)6例(5.4%)。所有血清标本均进行HBV DNA全基因组测序。随访5~7年,将发生LC、HCC、反复肝功能异常或死亡事件定义为疾病进展,探讨乙肝病毒开放编码区突变与疾病进展的关系。结果 S区T53C突变在CHB、LC、HCC组的发生率分别为9.7%、18.8%、25.0%,差异无统计学意义(P=0.269),P区G912A突变在3组的发生率分别为14.3%、28.6%、66.7%,差异有统计学意义(P=0.039)。随访5~7年,T53C在疾病未进展组、进展组的突变发生率分别为7.6%、24.1%,G912A在疾病未进展组、进展组的突变发生率分别为14.6%、36.4%,差异均有统计学意义(P〈0.05)。结论 S区T53C、P区G912A可能与乙肝相关肝病的进展有一定相关性。 展开更多
关键词 乙型肝炎病毒 慢性感染 T53C G912A 突变 预后
性能移动兼顾型Thinkpad R50 53C 预览
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《数码:移动通讯》 2004年第3期 91,共1页
关键词 IBM公司 THINKPAD R50 53C 笔记本电脑 配置 性能 外观设计
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三星:具有两个彩屏的A53C手机
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《信息技术时代》 2003年第1期 74,共1页
关键词 三星 彩屏 A53C 手机
尼龙聚合釜机械密封及辅助系统的研究 预览
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作者 张学刚 陆旭 《石油和化工设备》 CAS 2017年第6期100-102,共3页
对尼龙聚合釜机械密封及其辅助系统在工程中应用的案例进行分析,总结出尼龙聚合釜机械密封及其辅助系统的正确配置方案及选用原则。
关键词 尼龙聚合釜 机械密封 辅助系统 冲洗方案 PLAN53C 釜内取压
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Anti-de Sitter空间中具有常k阶平均曲率及两个不同主曲率的完备类空超曲面 预览
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作者 刘建成 魏艳 《兰州大学学报:自然科学版》 CAS CSCD 北大核心 2011年第2期 101-103,共3页
刻画了anti-de Sitter空间中具有常k阶平均曲率和两个不同主曲率的完备类空超曲面的黎曼积结构.
关键词 ANTI-DE SITTER空间 类空超曲面 k阶平均曲率 主曲率 黎曼积空间
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基于IOP80331的虚拟磁带库硬件设计与实现 预览
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作者 国大伟 《微计算机应用》 2010年第6期59-62,共4页
介绍了一种基于IOP80331的虚拟磁带库的硬件设计与实现。在分析虚拟磁带库硬件需求的基础上,详细阐述了基于IOP80331的虚拟磁带库控制器架构设计,处理器模块以及SCSI模块的设计实现,最后给出了挂载不同磁盘条件下的实际测试结果。
关键词 虚拟磁带库 IOP80331 LSI53C1030T SCSI
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Lower bounds for eigenvalues of the Dirac-Witten operator 被引量:1
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作者 YongFa Chen (1) 《中国科学:数学英文版》 SCIE 2009年第11期2459-2468,共10页
We get optimal lower bounds for the eigenvalues of the Dirac-Witten operator of compact(with or without boundary) spacelike hypersurfaces of Lorentian manifold satisfying certain conditions,just in terms of the mean ... We get optimal lower bounds for the eigenvalues of the Dirac-Witten operator of compact(with or without boundary) spacelike hypersurfaces of Lorentian manifold satisfying certain conditions,just in terms of the mean curvature and the scalar curvature and the spinor energy-momentum tensor. In the limiting case,the spacelike hypersurface is either maximal and Einstein manifold with positive scalar curvature or Ricci-flat manifold with nonzero constant mean curvature. 展开更多
关键词 Dirac-Witten OPERATOR eigenvalue mean CURVATURE SCALAR CURVATURE
On the solution of Dirichlet problem of complex Monge-Ampère equation on Cartan-Hartogs domain of the second type
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作者 WeiPing Yin (1) XiaoLan Yin (2) (3) 《中国科学:数学英文版》 SCIE 2009年第12期2829-2840,共12页
Complex Monge-Ampère equation is a nonlinear equation with high degree,so its solution is very diffcult to get.How to get the plurisubharmonic solution of Dirichlet problem of complex Monge- Ampère equation... Complex Monge-Ampère equation is a nonlinear equation with high degree,so its solution is very diffcult to get.How to get the plurisubharmonic solution of Dirichlet problem of complex Monge- Ampère equation on the Cartan-Hartogs domain of the second type is discussed by using the analytic method in this paper.Firstly,the complex Monge-Ampère equation is reduced to a nonlinear secondorder ordinary differential equation(ODE)by using quite different method.Secondly,the solution of the Dirichlet problem is given in semi-explicit formula,and under a special case the exact solution is obtained.These results may be helpful for the numerical method of Dirichlet problem of complex Monge-Ampère equation on the Cartan-Hartogs domain. 展开更多
关键词 COMPLEX Monge-Amp`ere EQUATION DIRICHLET problem Cartan-Hartogs DOMAIN Kaeh-
Laguerre calculus and Paneitz operator on the Heisenberg group
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作者 CHANG Der-Chen 《中国科学:数学英文版》 SCIE 2009年第12期2549-2569,共21页
Laguerre calculus is a powerful tool for harmonic analysis on the Heisenberg group.Many sub-elliptic partial differential operators can be inverted by Laguerre calculus.In this article,we use Laguerre calculus to fin... Laguerre calculus is a powerful tool for harmonic analysis on the Heisenberg group.Many sub-elliptic partial differential operators can be inverted by Laguerre calculus.In this article,we use Laguerre calculus to find explicit kernels of the fundamental solution for the Paneitz operator and its heat equation.The Paneitz operator which plays an important role in CR geometry can be written as follows:Here{Zj}n j=1 is an orthonormal basis for the subbundle T(1,0)of the complex tangent bundle TC(Hn) and T is the'missing direction'.The operator Lα is the sub-Laplacian on the Heisenberg group which is sub-elliptic ifαdoes not belong to an exceptional setΛα.We also construct projection operators and relative fundamental solution for the operator Lα whileα∈Λα. 展开更多
关键词 Paneitz OPERATOR HEISENBERG group LAGUERRE CALCULUS FUNDAMENTAL solution heat kernel spectrum
Adiabatic limits,vanishing theorems and the noncommutative residue
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作者 KeFeng Liu (1) (2) Yong Wang (1) (3) 《中国科学:数学英文版》 SCIE 2009年第12期2699-2713,共15页
In this paper,we compute the adiabatic limit of the scalar curvature and prove several vanishing theorems by taking adiabatic limits.As an application,we give a Kastler-Kalau-Walze type theorem for foliations.
关键词 FOLIATIONS ADIABATIC limits VANISHING THEOREMS NONCOMMUTATIVE RESIDUE
Twistor quantization of the space of half-differentiable vector functions on the circle revisited
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作者 SERGEEV Armen 《中国科学:数学英文版》 SCIE 2009年第12期2714-2729,共16页
We discuss the twistor quantization problem for the classical system(Vd,Ad),represented by the phase space Vd,identified with the Sobolev space H 1/2 0 (S1,Rd)of half-differentiable vector functions on the circle,and... We discuss the twistor quantization problem for the classical system(Vd,Ad),represented by the phase space Vd,identified with the Sobolev space H 1/2 0 (S1,Rd)of half-differentiable vector functions on the circle,and the algebra of observables Ad,identified with the semi-direct product of the Heisenberg algebra of Vd and the algebra Vect(S1)of tangent vector fields on the circle. 展开更多
关键词 twistor QUANTIZATION SOBOLEV SPACE of half-differentiable functions group of DIFFEOMORPHISMS of the circle
L-harmonic functions with polynomial growth of a fixed rate
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作者 ChaoHui Zhou (1) ZhiHua Chen (1) 《中国科学:数学英文版》 SCIE 2009年第12期2855-2862,共8页
Yau made the following conjecture:For a complete noncompact manifold with nonnegative Ricci curvature the space of harmonic functions with polynomial growth of a fixed rate is finite dimensional.we extend the result ... Yau made the following conjecture:For a complete noncompact manifold with nonnegative Ricci curvature the space of harmonic functions with polynomial growth of a fixed rate is finite dimensional.we extend the result on the Laplace operator to that on the symmetric diffusion operator,and prove the space of L-harmonic functions with polynomial growth of a fixed rate is finitedimensional,when m-dimensional Bakery-Emery Ricci curvature of the symmetric diffusion operator on the complete noncompact Riemannian manifold is nonnegative. 展开更多
关键词 L-harmonic function SYMMETRIC diffusion operator Bakery-Emery RICCI CURVATURE
Trace of heat kernel,spectral zeta function and isospectral problem for sub-laplacians
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作者 CHANG Der-Chen YEUNG Sai-Kee 《中国科学:数学英文版》 SCIE 2009年第12期2570-2589,共20页
In this article,we first study the trace for the heat kernel for the sub-Laplacian operator on the unit sphere in C n+1.Then we survey some results on the spectral zeta function which is induced by the trace of the h... In this article,we first study the trace for the heat kernel for the sub-Laplacian operator on the unit sphere in C n+1.Then we survey some results on the spectral zeta function which is induced by the trace of the heat kernel.In the second part of the paper,we discuss an isospectral problem in the CR setting. 展开更多
关键词 SUB-LAPLACIAN heat kernel CR-isospeCtral problem RIEMANNIAN ZETA function Mellin transform pseudo-hermitian structure
A quasi-local mass for 2-spheres with negative Gauss curvature 被引量:2
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作者 Xiao Zhang (1) 《中国科学:数学英文版》 SCIE 2008年第9期1644-1650,共7页
We extend our previous definition of quasi-local mass to 2-spheres whose Gauss curvature is negative, and prove its positivity.
关键词 general RELATIVITY quasi-local MASS POSITIVITY
S-curvature of isotropic Berwald metrics
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作者 Akbar TAYEBI Mehdi RAFIE-RAD 《中国科学:数学英文版》 SCIE 2008年第12期2198-2204,共7页
Isotropic Berwald metrics are as a generalization of Berwald metrics. Shen proved that every Berwald metric is of vanishing S-curvature. In this paper, we generalize this fact and prove that every isotropic Berwald m... Isotropic Berwald metrics are as a generalization of Berwald metrics. Shen proved that every Berwald metric is of vanishing S-curvature. In this paper, we generalize this fact and prove that every isotropic Berwald metric is of isotropic S-curvature. Let F = α + β be a Randers metric of isotropic Berwald curvature. Then it corresponds to a conformal vector field through navigation representation. 展开更多
关键词 S-CURVATURE ISOTROPIC Berwald METRIC ISOTROPIC S-CURVATURE NAVIGATION representa- tion
虚拟磁带库记录速度分析 预览 被引量:1
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作者 汪海山 康剑斌 +4 位作者 屠升平 马骋 熊剑平 刘宏 贾惠波 《计算机工程与应用》 CSCD 北大核心 2008年第3期 117-119,共3页
基于PCI-X总线和SCSI总线构架的虚拟磁带库,设计了一个以Intel公司的IOP芯片80331和LSI Logic公司的存储芯片1030T为核心的实验系统,然后测量了Ultra160总线、Ultra160磁盘和整个实验系统的速度,讨论了各个环节的速度匹配关系,最后分析... 基于PCI-X总线和SCSI总线构架的虚拟磁带库,设计了一个以Intel公司的IOP芯片80331和LSI Logic公司的存储芯片1030T为核心的实验系统,然后测量了Ultra160总线、Ultra160磁盘和整个实验系统的速度,讨论了各个环节的速度匹配关系,最后分析可知,在该实验条件下,磁盘是整个系统的速度瓶颈,选用更高速的磁盘可以进一步提高系统性能。 展开更多
关键词 虚拟磁带库 PCI-X SCSI LSI53C1030T IOP80331
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On mean curvatures in submanifolds geometry
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作者 JianQuan Ge (1) 《中国科学:数学英文版》 SCIE 2008年第6期1127-1134,共8页
By using moving frame theory,first we introduce 2p-th mean curvatures and(2p+1)-th mean curvature vector fields for a submanifold.We then give an integral expression of them that characterizes them as mean values of ... By using moving frame theory,first we introduce 2p-th mean curvatures and(2p+1)-th mean curvature vector fields for a submanifold.We then give an integral expression of them that characterizes them as mean values of symmetric functions of principle curvatures.Next we apply it to derive directly the celebrated Weyl-Gray tube formula in terms of integrals of the 2p-th mean curvatures and some Minkowski-type integral formulas. 展开更多
关键词 MOVING FRAME mean CURVATURE tube
Historical development of the Gauss-Bonnet theorem
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作者 WU Hung-Hsi(H.Wu) 《中国科学:数学英文版》 SCIE 2008年第4期777-784,共8页
A historical survey of the Gauss-Bonnet theorem from Gauss to Chern.
关键词 Gauss-Bonnet THEOREM CHERN CLASSES characteristic CLASSES
Hyperbolic positive mass theorem under modified energy condition
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作者 NaQing Xie (1) 《中国科学:数学英文版》 SCIE 2008年第12期2189-2197,共9页
We provide two new positive mass theorems under respective modified energy conditions allowing T00 negative on some compact set for certain modified asymptotically hyperbolic manifolds. This work is analogous to Zhan... We provide two new positive mass theorems under respective modified energy conditions allowing T00 negative on some compact set for certain modified asymptotically hyperbolic manifolds. This work is analogous to Zhang’s previous result for modified asymptotically ?at initial data sets. 展开更多
关键词 POSITIVE MASS THEOREM MODIFIED ENERGY CONDITION MODIFIED asymptotically hyper- bolic
胃癌组织中p53、C—erbβ—2和Ras的表达及其临床意义 预览 被引量:4
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作者 周戎二 陈力 《浙江医学》 CAS 2008年第1期 14-16,29,共4页
目的通过检测胃癌及正常胃黏膜组织中p53、C—erbβ-2及Ras三种癌相关基因蛋白产物,探讨这三种癌相关基因与胃癌发生、发展、分化和预后的关系及三者是否有协同作用。方法应用免疫组织化学法检测了82例原发性胃癌细胞中和18例正常胃黏... 目的通过检测胃癌及正常胃黏膜组织中p53、C—erbβ-2及Ras三种癌相关基因蛋白产物,探讨这三种癌相关基因与胃癌发生、发展、分化和预后的关系及三者是否有协同作用。方法应用免疫组织化学法检测了82例原发性胃癌细胞中和18例正常胃黏膜组织中p53、C—erbβ-2及Ras的表达,观察不同临床病理特征和生存期胃癌患者的阳性表达率。结果p53、C—erbβ-2、Ras在胃癌组织中的阳性表达率较正常胃黏膜均显著升高。有远处转移的胃癌患者p53阳性表达率明显高于无远处转移的胃癌患者;肿瘤直径〉4cm、有远处转移的胃癌患者C—erbβ-2阳性表达率明显高于肿瘤直径≤4cm、无远处转移的胃癌患者;肿瘤直径〉4cm的胃癌患者Ras阳性表达率明显高于肿瘤直径≤4cm的胃癌患者。p53、C—erbβ-2、Ras阳性表达者的5年生存率均显著低于阴性表达者。p53表达与C—erbβ-2表达呈正相关。结论p53的失活和突变以及C—erbβ-2、Ras的过度表达与胃癌的发生有关。p53、C—erbβ-2与胃癌的远处转移密切相关;p53、C—erbβ-2、Ras可作为判断胃癌患者预后的指标,突变型p53、C—erbβ-2及Ras的高表达提示患者预后较差,其中突变型p53与C—erbβ-2呈同步表达(正相关)。多基因联合检测能更充分地反映胃癌的生物学行为。 展开更多
关键词 P53 C—erbβ-2 RAS 胃癌 免疫组织化学法 预后
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