http://europepmc.org/abstract/MED/28481359
http://europepmc.org/abstract/MED/14506146
http://europepmc.org/abstract/MED/10777194
http://europepmc.org/abstract/MED/27262570
http://europepmc.org/abstract/MED/12802288
http://europepmc.org/abstract/MED/27705932