http://europepmc.org/abstract/MED/8052064
http://europepmc.org/abstract/MED/28481359
http://europepmc.org/abstract/MED/1341278
http://europepmc.org/abstract/MED/26619122
http://europepmc.org/abstract/MED/12879021
http://europepmc.org/abstract/MED/8380055