另一个重要因素是消除谐波的回声在更高的频率，导致更多的细节，仍然是一个平滑，更自然的声音。

Another vital element is the removal of harmonic echoes in the higher frequencies, which result in a lot more detail and still a smoother and more natural sound.

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分别用二次谐波显像及彩色能量多普勒成像，观察造影前后局部损伤的位置、范围及回声。

Detecting visualization of segmental renal trauma on both second harmonic imaging(SHI)and color Doppler energy imaging(CDEI)before and after enhanced ultrasonography.

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