1. Department of Internal Medicine I, Martin-Luther-University Halle-Wittenberg, Saale, Germany
2. Department of General, Visceral, Vascular and Endocrine Surgery, Martin-Luther-University Halle-Wittenberg, Saale, Germany
3. Department of Internal Medicine I, Martin-Luther-University Halle-Wittenberg, Ernst-Grube-Strasse 40, D-06120 Halle, Saale, Germany