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二维斑点追踪成像对二尖瓣反流患者二尖瓣成形术前后左室扭转运动改变的评估 被引量:2
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作者 周鼎文 禇雯 +2 位作者 王华 王振华 张社芳 《中国中西医结合影像学杂志》 2021年第4期354-357,共4页
目的:使用二维斑点追踪成像(2D-STI)评估二尖瓣反流患者二尖瓣成形术前后左室扭转运动的改变。方法:选取30例拟行二尖瓣成形术的二尖瓣反流患者(患者组)和年龄、性别与其相近的30例健康志愿者(对照组),2组术前1周、术后1个月均行常规超... 目的:使用二维斑点追踪成像(2D-STI)评估二尖瓣反流患者二尖瓣成形术前后左室扭转运动的改变。方法:选取30例拟行二尖瓣成形术的二尖瓣反流患者(患者组)和年龄、性别与其相近的30例健康志愿者(对照组),2组术前1周、术后1个月均行常规超声心动图检查及后期2D-STI脱机分析,获得常规超声心动图参数及扭转角度峰值(Ptw),对比成形术前后常规参数及Ptw的变化,并探究容量负荷改变对扭转功能的影响。结果:患者组术前左室舒张末期容积(LVEDV)及左室收缩末期容积(LVESV)分别为(134.99±23.62)、(44.58±9.10)mL,显著高于对照组的(80.97±9.56)、(27.87±3.61)mL(均P<0.05),这2个参数在患者组术后降低,但均高于对照组,差异均有统计学意义(均P<0.05)。患者组Ptw值术前、术后分别为12.41°±3.50°、9.30°±2.57°,术后较术前降低(P<0.05);对照组Ptw值8.29°±1.67°,与患者组术前比较差异有统计学意义(P<0.05),与术后对比差异无统计学意义(P>0.05)。Pearson相关分析表明,Ptw与LVEDV呈中度相关性(r=0.432,P<0.001)。结论:左心功能代偿期中重度二尖瓣反流患者Ptw值受容量负荷增加而增大,二尖瓣成形术后恢复正常,且Ptw与LVEDV呈中度相关性。Ptw可较敏锐地发现左心室心肌在容量负荷影响下代偿性运动增强,可为临床诊断和治疗提供参考依据。 展开更多
关键词 二尖瓣闭锁不全 二尖瓣瓣膜成形术 超声检查
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二维斑点追踪成像对术前左室射血分数正常的重度二尖瓣反流患者左室长轴纵向心肌分层应变的评价 被引量:2
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作者 周鼎文 禇雯 +1 位作者 王华 张社芳 《中国中西医结合影像学杂志》 2020年第5期474-477,485,共5页
目的:探讨二维斑点追踪成像技术(2D-STI)评估术前左室射血分数(LVEF)正常的重度二尖瓣反流患者左室长轴纵向心肌分层应变的意义。方法:选择准备行二尖瓣手术的LVEF正常的重度二尖瓣反流患者30例,依据术后LVEF值分为A组18例(LVEF≥50%)和... 目的:探讨二维斑点追踪成像技术(2D-STI)评估术前左室射血分数(LVEF)正常的重度二尖瓣反流患者左室长轴纵向心肌分层应变的意义。方法:选择准备行二尖瓣手术的LVEF正常的重度二尖瓣反流患者30例,依据术后LVEF值分为A组18例(LVEF≥50%)和B组(LVEF<50%)12例;对照组选择年龄、性别与其匹配的30例健康志愿者。比较3组超声心动图常规参数及左室长轴纵向心肌分层应变值。结果:A组较对照组仅心内膜下心肌分层应变绝对值减低,中层心肌和心外膜心肌分层应变绝对值呈减低趋势,但差异无统计学意义(P> 0.05),B组较对照组和A组3层心肌分层应变值绝对值均减低,差异均有统计学意义(均P<0.05)。结论:2D-STI通过评价术前LVEF正常的重度二尖瓣反流患者左室长轴心肌分层应变,从而判断左心室心肌是否受累及受累程度,对指导临床选择合适的手术时机有一定意义。 展开更多
关键词 二尖瓣闭锁不全 心室功能 超声心动描记术
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Preliminary analysis on the relationships between Tibetan Plateau NDVI change and its surface heat source and precipitation of China 被引量:14
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作者 HUA Wei FAN Guangzhou +5 位作者 zhou dingwen NI ChangJian LI XueMin WANG YongLi LIU YaQin HUANG XianLun 《Science China Earth Sciences》 SCIE EI CAS 2008年第5期677-685,共9页
Using the automatic weather station data obtained from the Tibetan Plateau (TP), the normalized dif- ference vegetation index and the monthly precipitation data of China and by the methods of correlation and composite... Using the automatic weather station data obtained from the Tibetan Plateau (TP), the normalized dif- ference vegetation index and the monthly precipitation data of China and by the methods of correlation and composite analysis, preliminary analytical results are achieved concerning the relationships be- tween TP NDVI change and its surface heat source and precipitation of China. The results of our re- search may lead to the following conclusions: (1) A positive correlation relationship exists between TP NDVI change and its surface heat source, including the sensible heat and the latent heat. As to the correlation of the former, it is more remarkable in western TP than in eastern TP, and as to the correla- tion of the latter, however it turns out contrary. (2) With the improvement of TP vegetation, its surface heat source of every season is also mainly reinforced, especially in summer. As to the contribution of the sensible heat and the latent heat to the increment of the TP surface heat source intensity, the for- mer is comparatively more significant than the latter in winter and spring, while in summer and autumn, the two have almost the same importance. (3) The correlation coefficient between summer NDVI over TP and the corresponding period precipitation of China displays a belt distribution of "+?+" from south to north China. (4) Anomalous surface heating field over TP derived from vegetation change is probably an important factor to affect summer precipitation of China. 展开更多
关键词 TIBETAN Plateau vegetation CHANGE SURFACE heat source PRECIPITATION of China
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