他随身携带了无线电设备，以便在紧急情况下呼叫经过这里的飞行员，但最终发现设备根本不起做用。
He carried a radio so he could call commercial airline pilots to relay messages in case of emergency, but he discovered that it wasn't working.
动态心电图这是一种可随身携带的心电图，可以在你正常生活时连续记录下几天内心脏的电活动。
Holter monitor. This portable ECG device can be worn for a day or more to record your heart's activity as you go about your routine.
动态心电图这是一种可随身携带的心电图，可以在你正常生活时连续记录下几天内心脏的电活动。
Holter monitor. This portable ECG device can be worn for a day or more to record your heart's activity as you go about your routine.
应用推荐