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高血压患者左室向心性结构与舒张功能减退相关:HyperGEN研究

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世界核心医学期刊文摘（心脏病学分册） 2005年第10期1卷 48-48页

作者： De Simone G. Kitzman D. W. chinali m. 郭战宏 Department of Clinical and Experimental medicine Federico II University Hospital v. S. Pansini 5 80131 Naples Italy

We tested the hypothesis that abnormal left ventricular(LV) relaxation is associated with concentric LV geometry. methods and results: Doppler LV filling properties were studied in 1384 hypertensive participants without cardiovascular disease, from the HyperGEN population(731 women, 784 obese, 236 diabetic) and compared in four LV geometry groups; normal, concentric remodelling(3.5% ), eccentric(23% ), and concentric LV hypertrophy(4% ), based on echocardiographic LV mass index(in g/m2.7). Abnormal LV relaxation was identified by European Society of Cardiology criteria in 275 subjects(20% ). After accounting for significant confounders, E/A ratio and isovolumic relaxation time were not related to the presence of LV hypertrophy, but indicated abnormal relaxation when LV geometry was concentric(both Pme of E velocity was prolonged with LV hypertrophy(Pmetry differed in the presence(prolonged) or absence(reduced) of LV hypertrophy(P=0.05), a difference independently related to the magnitude of both transmitral gradients and stroke volume(all Pmpared with normal LV geometry, the odds of abnormal LV relaxation was 2.3- fold greater when LV geometry was concentric and that LV hypertrophy conferred a borderline higher risk than normal LV mass. Conclusions: In hypertensive individuals without prevalent cardiovascular disease from a multi-ethnic population-based sample, delayed LV relaxation is independently associated with concentric LV geometry.

关键词： HyperGEN 舒张功能减退向心性质量指数心血管疾病等容舒张时间离心性超声心动检查心脏病学混杂因素

A Global Pinching Theorem for Compact Surfaces in S^3 with Constant mean Curvature

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Acta mathematica Sinica,English Series 1996年第2期12卷 126-132页

作者： Hu Zejun Li Haizhong Hu Zejun Department of mathematics Zhengzhou University Zhengzhou,450052 chinali Haizhong Department of Applied mathematics Tsinghua University Beijing,100084 China 郑州大学数学系河南郑州清华大学应用数学系北京

Let m be a compact minimal surface in S3.*** proved that if ‖S‖2≤2(21/2π, then m is either the equatorial sphere or the Clifford torus,where 5" is the square of the length of the second fundamental form of m,‖·‖2 denotes the L2-norm on *** this paper,we generalize Hsu’s result to any compact surfaces in S3 with constant mean curvature.

关键词： Compact surface Constant mean curvature Global pinching

STUDY OF K_2O·6TiO_2 WHISKER REINFORCED AI COmPOSITES FOR THEIR mECHANICAL PROPERTIES AND INTERFACIAL STRUCTURES

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Acta metallurgica Sinica(English Letters) 1994年第2期7卷 119-123页

作者： PA N JinChangsha Institute of Technology, chinali Jihong, NING Xiaoguang, YE HengqiangLab. of Atomic Imaging of Solids, Institute of metal Research, Chinese Academy of Sciences. Shenyang, China manuscript received 28 February, 1994

A newly developed whisker K_(2)O 6TiO_(2) reinforced 6061 Al composite was prepared by squeeze casting process. The flexural strength of the composite is 518mPa, and decreases to 490 m Pa after T6 *** hardness of the composite also shows the similar change while T6 treating. The results of HRTEmobservation may explaine this property change. It was considered that there is a continuous TiO layer at the whisker-matrix interface, which is easily to react with the segregated mg and to form mgTi_(2)O_(4), mgAl_(2)O_(4). The thickening of TiO layer after T6 treatment is the main reason resulting in strength degradation of composite.

关键词： potassium titanate. whisker aluminium alloy composites interface

PREPARATION AND SOLIDIFICATION CHARACTERISTIC OF IN SITU DIRECTIONALLY SOLIDIFIED EUTECTIC Al_(11)La_3/Al COmPOSITE

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Acta metallurgica Sinica(English Letters) 1993年第5期6卷 278-282页

作者： DONG Hongbiao JI Yongyi ZHU Jun LU Shuzu ZHONG Xueyou University of Science and Technology,Beijing,chinali Jianguo Northwestern Polytechnical University,Xi’an,China DONG Hongbiao,lecturer,Department of metallurgy,University of Science and Technology Beijing,Beijing 100083,China

In situ eutectic Al_(11)La_3/Al composite material with regular arrangement was prepared by zone melt liquid metal cooling directionally solidification under conditions of high temperature gradient G=700K/cm and growth rate R=6.0-20.0μm/*** diffraction pat- tern of Al_(11)La_3/Al composite shows that the preferred growth direction is[100]Al// [33]Al_(11)La_3,and the habit plane is(002)Al//(116)Al_(11)La_3.A low density(103)twin is ob- served in Al_(11)La_3 and the growth of(103)twin induces to branching to change the interlamellar spacing.

关键词： eutectic solidification directional solidification AI+(La,Al)

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塔河油田七区油气区带划分与评述

石油物探 2004年第6期43卷 556-563页

作者：张秀荣李保华胡国山中国石化西北分公司工程技术研究院，新疆乌鲁木齐830011

塔河油田七区碳酸盐岩储层埋藏深,厚度变化大,储集层非均质性强,孔、缝、洞系统变化大,给储层对比和寻找油气分布规律带来较大困难。通过测井资料的纵、横向对比与追踪,结合地震、钻井及试采资料,依据地层岩性、储层特性、构造及断裂特... 详细信息

塔河油田七区碳酸盐岩储层埋藏深,厚度变化大,储集层非均质性强,孔、缝、洞系统变化大,给储层对比和寻找油气分布规律带来较大困难。通过测井资料的纵、横向对比与追踪,结合地震、钻井及试采资料,依据地层岩性、储层特性、构造及断裂特征,发现现今岩溶地貌特征是古构造运动及同期产生的断裂和古岩溶发育特征的显露,三者有机结合,对该区进行了油气区带划分与评价,从中找出了区带特点和高产油气区带。

关键词：塔河油田区带油气分布规律储层特性试采钻井非均质性古岩溶碳酸盐岩储层断裂特征