Select_list = ["Amygdala", "Hippocampus", "Lateral-Ventricle", "Pallidum", "Putamen", "Thalamus", "Caudate"]
Side = ["Left", "Right"]
#Selected columns
if(Select_list):
    for s in Side:
        for struct in Select_list:
            volumes_c = group_c.filter(regex="^(?=.*"+s+")(?=.*"+struct+")(?=.*Volume)")