_:vb50941756 . _:vb50941756 . _:vb50941756 . _:vb50941756 "A Parkinsonism that is characterized by postural instability, a broad-based gait with the absence of tremors of vascular origin."^^ . _:vb50941756 "url:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6327701/"^^ . _:vb50941756 .