http://europepmc.org/abstract/MED/18772396
http://europepmc.org/abstract/MED/28481359
http://europepmc.org/abstract/MED/23441165
http://europepmc.org/abstract/MED/28218421
http://europepmc.org/abstract/MED/28805995
http://europepmc.org/abstract/MED/25740784