1. Department of Internal Medicine I (Gastroenterology, Gastroenterologic Oncology, Hepatology, Infectiology and Geriatric Medicine), University Hospital Tuebingen, D‑72076 Tuebingen, Germany
2. Department of Internal Medicine VIII (Medical Oncology and Pneumology), University Hospital Tuebingen, D‑72076 Tuebingen, Germany
3. Boehringer Ingelheim Pharma GmbH and Co. KG, D‑88397 Biberach/Riss, Germany
4. Department of Vegetative and Clinical Physiology, University Hospital Tuebingen, D‑72076 Tuebingen, Germany