title: Letter: Tuberculins old or purified.
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007194:India; D007223:Infant; D008297:Male; D014373:Tuberculin / Q000592:standards*; D014374:Tuberculin Test; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis*
chemical_list: D014373:Tuberculin