http://europepmc.org/abstract/MED/23907151
http://europepmc.org/abstract/MED/29681454
http://europepmc.org/abstract/MED/28481359
http://europepmc.org/abstract/MED/29420467
http://europepmc.org/abstract/MED/18948947
http://europepmc.org/abstract/MED/26164066
http://europepmc.org/abstract/MED/22510280
http://europepmc.org/abstract/MED/24069199
http://europepmc.org/abstract/MED/25112956
http://europepmc.org/abstract/MED/27923066
http://europepmc.org/abstract/MED/16140923
http://europepmc.org/abstract/MED/22980975
http://europepmc.org/abstract/MED/27105424