Patients or research volunteers with abnormalities that contraindicate, or increase the risk of, fiberoptic bronchoscopy and bronchoalveolar lavage, including a history of allergy to atropine, lidocaine, or other topical anesthetics or premedications; FEV(1) less than 0.8 liters; PaO(2), on supplemental 02, of less than 70 mmHg or PaCO(2) greater than 45 mmHg; presence of uncorrected clotting disorder, uncontrolled hypertension, significant cardiac disease, renal or liver failure; metastatic disease; hematologic disorders such as severe anemia (hemoglobin less than or equal to 7 g/ml), granulocytopenia, or platelet disorders.