[Epidemiologic study of heart diseases in 7,168 school children].
D000293:Adolescent; D002648:Child; D002681:China; D005260:Female; D006330:Heart Defects, Congenital / Q000453:epidemiology; D006331:Heart Diseases / Q000453:epidemiology*; D006337:Heart Murmurs; D006349:Heart Valve Diseases / Q000453:epidemiology; D006801:Humans; D008297:Male; D008945:Mitral Valve Prolapse / Q000453:epidemiology; D012214:Rheumatic Heart Disease / Q000453:epidemiology