http://europepmc.org/abstract/MED/24736102
http://europepmc.org/abstract/MED/21822264
http://europepmc.org/abstract/MED/28481359
http://europepmc.org/abstract/MED/25021421
http://europepmc.org/abstract/MED/29487225
http://europepmc.org/abstract/MED/23830926