Methods: withdraw the envelope of heat sounds by using Mathematic Morphology and normalized Shannon energy, extract first heart sound and the second heart sound.

利用数学形态学和归一化香农能量两种方法分别提取了心音的包络，突出了第一心音、第二心音等特征。

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Results: Their main cause to colour Doppler echocardiography were murmur, cyanosis, panting, asphyxia, feeding-difficulty, Loud pulmonary valve second heart sound.

结果：进行心脏彩超检查的原因以心脏杂音、紫绀、宫内窘迫或新生儿窒息、呼吸急促、肺动脉瓣第二心音亢进最常见。

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The clinical experiments have indicated that the first and second heart sound can be almost acquired by the microphone, but it is difficult for the third and fourth, w…

临床实验表明，利用驻极体传声器基本上能采集到正常的第一、第二心音，但对有病理信息的第三、第四心音却不易正确采集到，这与患者性别和胖、瘦等因素均有关系。

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