keywords Amino Acid Sequence Animals Antibody Specificity Base Sequence Bleomycin Cell Division Lung Macrophages, Alveolar Male Molecular Sequence Data Proliferating Cell Nuclear Antigen Pulmonary Alveoli Pulmonary Fibrosis RNA, Messenger Rats Rats, Sprague-Dawley Receptor, Epidermal Growth Factor Respiratory Distress Syndrome, Adult Specific Pathogen-Free Organisms Transforming Growth Factor alpha