回声

She shouted on the mountaintop and listened for the echo.

她在山顶上大喊着，然后聆听着。

The echo resounded back to us.

传到们耳中。

Our findings indicate that both opsin genes have been under purifying selection in the majority bats despite a long history of nocturnality.

但对恒频蝙蝠而言，视觉退化根本原因在于它具有一种更发达定位能力。

Methods The size,echo intensity on 2-DUS and blood flow on CDFI in sternocleidomastoid mascle(SCM) masses in 46 infants were examined,measured and analysed.

方法总结析46例胸锁乳突肌(SCM)肿块超检查资料,析其大小、内部及多普勒血流信号。

I tapped the melon lightly, the way my mother does in the supermarket, listening for the hollow sound of the freshness: Pung, pung.

像母亲在市场挑瓜那，在瓜上轻轻地敲了敲，听里面有没有空洞洞瓜熟音。果然传来“砰砰”。

The imaging protocol for the mica samples consisted of a spin-echo pulse sequence with multiecho acquisition to collect images at seeral parallel echo times, the authors explained.

该研究报告作者解释，云母标本成像协议包括自旋脉冲串和在几个平行时间段收集多影像。