triad

At tetrad stage, dyad, triad, tetrad with micronucleus and polyad appeared.

四分体时期还出现二分体、分体、含微核的异常四分体及多分体。

Dyskeratosis congenita (DKC) is a rare inherited disease characterized by the triad of abnormal skin pigmentation, nail dystrophy, and mucosal leukoplakia.

先化不良症（DKC）为一少见之遗传疾病，项主要特徵为皮肤色素异常、 指甲生长异常及黏膜白斑症。