基本概述痰在医学上的定义，是指肺及支气管等鼻腔以下的呼吸管道的粘膜所分泌、用来把异物排出体外的粘液，特别是经过咳嗽吐出来的分泌。痰过多的话就应该引起重视了，并采取相应措施。在人的呼吸道里，许多小纤毛麦浪一样朝向口腔的方向，慢慢将脏东西推出来，推到嗓子眼儿时，人就会咳嗽吐痰。每个人的痰密度不同，里面什么样的细菌都可能携带。如果随便乱吐，痰变干后，痰中成千上万的细菌就会飘到空气中
COPD是一种严重的肺病可造成呼吸困难，症状包括呼吸困难、久咳和痰多。
COPD is a serious lung disease that makes breathing difficult. Symptoms can include breathlessness, chronic cough and excessive phlegm.
患有COPD的个人通常会经历到无法呼吸、咳嗽与痰多，其于急性发作时可能会更恶化。
Individuals with COPD often experience breathlessness, cough and sputum which may worsen during acute flare-ups.
能提示严重情况的其他症状，她说，包括全身瘙痒、咳嗽、痰多、呼吸短促、心悸、胸痛及腹泻。
Other symptoms that can indicate a severe problem, she said, include itching, cough, sputum production, shortness of breath, palpitations, chest pain and diarrhea.
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