1. Department of Pulmonary Medicine, University Hospital Bern, 3010 Bern, Switzerland.
2. Department of Clinical Research, University of Bern, 3010 Bern, Switzerland.
3. Institute of Functional and Applied Anatomy, Hannover Medical School, 30625 Hannover, Germany.
4. Department of Pathology, University of Bern, 3010 Bern, Switzerland.
5. Division of Thoracic Surgery, University Hospital Bern, 3010 Bern, Switzerland.