Experimental: thalidomide group α‐interferon: nebulized inhalation, 5 million U or equivalent dose added 2 ml of sterile water for injection, 2 times a day, for 7 days; abidol, 200 mg/time, 3 times a day, for 7 days; methylprednisolone: 40 mg, q12h, for 5 days. thalidomide: 100 mg/d qn for 14 days