Dong-ke CHEN ; Jin-shu HU ; Xong-tao XU
Chinese Journal of Epidemiology 2007;28(10):1044-1044
Bacterial Typing Techniques ; Carrier State ; microbiology ; Child ; Child, Preschool ; Drug Resistance, Bacterial ; Female ; Haemophilus ; classification ; drug effects ; Haemophilus Infections ; microbiology ; Humans ; Male ; Respiratory Tract Infections ; microbiology