7Weiss ST. Eat dirt - the hygiene hypothesis and allergic diseases [J]. N Engl J Med, 2002,347(12):930-931.
8Warren DW. Effect of airway obstruction upon facial growth [J]. Otolaryngol Clin North Am, 1990,23(4) :699 -712.
9Zhang L, Han D, Huang D, et al. Prevalence of self- reported allergic rhinitis in eleven major cities in China[J]. Int Arch Allergy Immunol, 2008,149.47-57.
