http://europepmc.org/abstract/MED/28481359
http://europepmc.org/abstract/MED/27401243
http://europepmc.org/abstract/MED/9230279
http://europepmc.org/abstract/MED/26928463
http://europepmc.org/abstract/MED/11011123
http://europepmc.org/abstract/MED/22722839