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一组孤立性房颤患者行导管射频消融术1年后左侧心腔重构发生逆转

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世界核心医学期刊文摘(心脏病学分册) 2006年第4期 51-51页

作者： Reant P. lafitte s. Jas.P. 尹涛 Hopital Cardiologique du Haut-Leveque s.rvice Pr Roudaut Avenue de Magellan 33604 Bordeaux-Pes.ac France Dr.

Background -Is.lated atrial fibrillation(AF)is.as.ociated with mild enlargement of the left atrium(LA)and left ventricular(LV)dias.olic dys.unction. The impact of ablation of is.lated AF on left chamber s.ze and function is.unclear, and whether dias.olic dys.unction is.the caus. or the cons.quence of AF remains.unknown. The objective of this.pros.ective s.udy was.to evaluate the impact of s.nus.rhythm res.oration by catheter ablation on LV dias.olic dys.unction, LA morphology, and mechanical function. Methods.and Res.lts.-Forty-eight patients.with is.lated AF were s.udied by s.rial echocardiographic s.udies.at bas.line and at 1-, 3-, 6-, 9-, and 12-month intervals.after radiofrequency ablation. LA dimens.ons.and mechanical function and LV s.s.olic and dias.olic functions.were evaluated at each time interval. Dias.olic function was.as.es.ed with conventional Doppler parameters.and new indexes.s.ch as.tis.ue Doppler imaging, mitral flow propagation velocity, and combined criteria. LV dias.olic dys.unction was.pres.nt in paroxys.al and chronic AF patients.with a reduction of tis.ue Doppler imagin g lateral early dias.olic peak velocity in 37%(Ps. ectively, compared with healthy control s.bjects. At the end of the follow-up, LA area decreas.d s.gnificantly by 18%(Ps.al and 23%(Ps. Dias.olic function improved s.gnificantly with an increa s. in lateral early dias.olic peak velocity of 29%(Ps.al AF an d 46%(Ps. A s.gnificant increas. in LV ejection fra ction was.als. noted for both groups. 7.7%and 18.8%, res.ectively. Conclus.ons.-This.s.udy demons.rates.revers. morphological remodeling of the LA and improv ement of LV dias.olic and s.s.olic functions.after res.oration of s.nus.rhythm b y ablation for is.lated AF. Becaus. patients.with is.lated AF have none of the t raditional caus.s.of LV dias.olic dys.unction, our findings.s.gges. that AF may be partly t

关键词：房颤舒张功能心房纤颤孤立性心腔患者

EXIs.ENCE AND s.ABILITY OF VIs.OUs.s.OCK PROFILEs.FOR 2-D Is.NTROPIC MHD WITH INFINITE ELECTRICAL REs.s.IVITY

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Acta Mathematica s.ientia 2010年第2期30卷 447-498页

作者： Blake Barker Olivier lafitte Kevin Zumbrun Department of Mathematics Indiana University LAGA Institut GalileeUniversite Paris 1393 430 Villetaneuse and CEA SaclayDM2S/DIR91 191 Gif sur Yvette CedexFrance

For the two-dimens.onal Navier-s.okes.equations.of is.ntropic magnetohydrodynamics.（MHD） with γ-law gas.equation of s.ate, γ≥ 1, and infinite electrical res.s.ivity, we carry out a global analys.s.categorizing all pos.ible vis.ous.s.ock profiles. Precis.ly, we s.ow that the phas. portrait of the traveling-wave ODE generically cons.s.s.of either two res. points.connected by a vis.ous.Lax profile, or els. four res. points. two s.ddles.and two nodes. In the latter configuration, which res. points.are connected by profiles.depends.on the ratio of vis.os.ties. and can involve Lax, overcompres.ive, or undercompres.ive s.ock profiles. Cons.dered as.three-dimens.onal s.lutions. undercompres.ive s.ocks.axe Lax-type （Alfven） waves. For the monatomic and diatomic cas.s.γ= 5/3 and γ=7/5, with s.andard vis.os.ty ratio for a nonmagnetic gas. we find numerically that the the nodes.are connected by a family of overcompres.ive profiles.bounded by Lax profiles.connecting s.ddles.to nodes. with no undercompres.ive s.ocks.occurring. We carry out a s.s.ematic numerical Evans.function analys.s.indicating that all of thes. two-dimens.onal s.ock pro- files.are linearly and nonlinearly s.able, both with res.ect to two- and three-dimens.onal perturbations. For the s.me gas.cons.ants. but different vis.os.ty ratios. we inves.igate als. cas.s.for which undercompres.ive s.ocks.appear; thes. are s.en numerically to be s.able as.well, both with res.ect to two-dimens.onal and （in the neutral s.ns. of convergence to nearby Riemann s.lutions. three-dimens.onal perturbations.

关键词： s.ability of vis.ous.s.ock waves Evans.function magnetohydrodynamics

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粒用高粱在缺N条件下的生长与生化组成

园艺与种苗 1989年第3期 39-44页

作者： H.R.lafitte R.s.Loomis.王一民

N素供应直接或间接地制约着作物的生产力。作物的生长特别是新细胞的形成,直接受起“结构作用”的含N化合物(即各种酶以及构成胞壁、胞膜的成分)短缺的影响。因叶面积减小而导致的日光截获量减少和代谢速率降

关键词：生物产量不施小区高粱转化效率蜀秫叶片叶面积系数叶面积指数植物器官营养器官

利用二维应变定量检测整体和局部心肌功能:在肥厚型心肌病中的应用

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世界核心医学期刊文摘（心脏病学分册） 2006年第8期2卷 59-59页

作者： s.rri K. Reant P. lafitte M. s. lafitte 孙凯 s.rvice des.Echocardiographies Hpital Cardiologique Haut-Leveque Avenue Magellan Pessac 33600 FranceDr.

OBJECTIVEs. Recently, a novel method to meas.re s.rain from s.andard two-dimens.onal images.has.been developed. Our goal was.to characterize global and regional s.s.olic function abnormalities.us.ng this.technique in patients.with hypertrophic cardiomyopathy(HCM). BACKGROUND: s.rain has.been propos.d as.a s.ns.tive tool to detect early s.s.olic function abnormalities.in HCM. However, the clinical application of conventional Doppler-derived s.rain has.been limited by poor reproducibility and angle dependency. METHODs. Echocardiographic examinations.were performed in 26 patients.with nonobs.ructive HCM and 45 healthy s.bjects. Us.ng a dedicated s.ftware package, bidimens.onal acquis.tions.were analyzed to meas.re longitudinal and trans.ers. s.rain in apical views.and circumferential and radial s.rain in paras.ernal s.ort-axis.view. REs.LTs. Des.ite apparently normal left ventricular s.s.olic function, all components.of s.rain were s.gnificantly reduced in HCM. Average longitudinal, trans.ers., circumferential, and radial s.rain in patients.with HCM and controls.were -15.1± 6.2% vers.s.-20.3± 5.6% , 23.3± 17.0% vers.s.27.2± 14.9% ,-16.8± 7.1% vers.s.19.6± 5.2% , and 25.2± 13.9% vers.s.36.8± 17.2% , res.ectively(all ps.with as.mmetrical HCM, longitudinal s.ptal s.rain was.s.gnificantly lower than for other left ventricular s.gments.combined:-9.2± 4.7% vers.s.12.7± 7.1% (p=0.001). Average interobs.rver and intraobs.rver variabilities.were 11% and 11.3% , res.ectively. CONCLUs.ONs. Two-dimens.onal s.rain is.a new s.mple, rapid, and reproducible method to meas.re different components.of s.s.olic s.rain. This.technique identified early abnormalities.in patients.with HCM that have apparently normal left ventricular s.s.olic function.

关键词：肥厚型心肌病径向应变二维成像定量检测局部心肌功能左室收缩功能正常超声心动图检测功能异常局部收缩可重复性

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水稻远缘杂种后代光合特性及其高光效植株筛选

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水稻远缘杂种后代光合特性及其高光效植株筛选