[1] Univ Hosp Munster, Clin Phoniatr & Pedaudiol, Munster, Germany
[2] Univ Hosp Munster, Dept Pediat Hematol & Oncol, Childrens Hosp, Munster, Germany
[3] Univ Munster, Inst Biostat & Clin Res, D-48149 Munster, Germany
[4] Univ Hosp Munster, Expt Nephrol Dept Internal Med D, Munster, Germany
[5] Univ Hosp Erlangen, Dept Hematol Oncol Cell Therapy, Hosp Children & Adolescents, Erlangen, Germany
[6] Univ Erlangen Nurnberg, Inst Expt & Clin Pharmacol & Toxicol, D-91054 Erlangen, Germany