Zhejiang Provincial Center for Disease Control and Prevention;
Hangzhou 310051;
Zhejiang;
China;
The First Affiliated Hospital.Zheijang University;
Hangzhou 310003;
Zheiiang;
China;
Zhejiang International Travel Healthcare Center;
Hangzhou 310009;
Zhejiang;
China;
The Second Affiliated Hospital;
Zhejiang University;
Hangzhou 310009;
Zhejiang;
China;
An Epistaxis Emergency Associated with Multiple Pollutants in Elementary Students;