Observation of the effectiveness of pumping sputum by sequential mechanical ventilation combined with vibrating sputum-ejection apparatus in the treatment of 12 cases of severe respiratory failure是什么意思_Observation of the effectiveness of pumping sputum by sequential mechanical ventilation combined with vibrating sputum-ejection apparatus in the treatment of 12 cases of severe respiratory failure在线翻译_英语_读音_用法_例句