In a study in the American Journal of Respiratory and Critical Care Medicine, researchers examined this by comparing airflow in people when they hummed and when they quietly exhaled.
美国医学杂志《呼吸道与急救护理杂志》的研究者是通过比较哼绵羊音与一般平稳吐气时的气流而得到该结论。
2
Sleep apnea syndrome is defined as repeated episodes of cessation of airflow with sleep, often defined with a respiratory disturbance incidence (RDI) being greater than 5 or 10.
睡眠呼吸暂停综合征被定义为睡眠时反复发生气流断绝，经常被定义为大于5或10的呼吸障碍（RDI）。
3
Chronic obstructive pulmonary disease (COPD) is one of common respiratory diseases that features incompletely reversible airflow obstruction.