A.T. EGOROVA 1,2, N.Kh. ZHAMLIKHANOV 1,2, D.A. MALLIN 1,2 1Chuvash State University named after I.N. Ulyanov, 15 Moskovskiy Alley, Cheboksary, Russian Federation, 428000 2City Children’s Hospital No.3 of the Ministry of Healthcare of the Chuvash Republic, 12 Traktorostroiteley Ave., Cheboksary, Russian Federation, 428000 Egorova K.V. – post-graduate student of the Department of Pediatrics, Otorhinolaryngologist of […]