<n0:ComplexDefinition xmlns:n0="http://ncicb.nci.nih.gov/xml/owl/EVS/ComplexProperties.xsd#"><n0:def-definition>A rare, milder form of amyotrophic lateral sclerosis. It is characterized by a slowly progressive clinical course. Signs and symptoms include muscle weakness, atrophy, and fasciculation.</n0:def-definition><n0:def-source>NCI</n0:def-source></n0:ComplexDefinition>