http://europepmc.org/abstract/MED/28481359
http://europepmc.org/abstract/MED/28218421
http://europepmc.org/abstract/MED/23917401
http://europepmc.org/abstract/MED/22821383
http://europepmc.org/abstract/MED/20068183
http://europepmc.org/abstract/MED/24714777