Explorative study of emerging blood biomarkers in progressive multiple sclerosis (EmBioProMS): Design of a prospective observational multicentre pilot study oleh Ahmed Abdelhak, Andre Huss, Alexander Stahmann, Makbule Senel, Markus Krumbholz, Markus C. Kowarik, Joachim Havla, Tania Kümpfel, Ingo Kleiter, Isabella Wüstinger, Uwe K. Zettl, Margit Schwartz, Romy Roesler, Tim Friede, Albert C. Ludolph, Ulf Ziemann, Hayrettin Tumani