http://europepmc.org/abstract/MED/24218139
http://europepmc.org/abstract/MED/24077845
http://europepmc.org/abstract/MED/21576631
http://europepmc.org/abstract/MED/24045501
http://europepmc.org/abstract/MED/22390313
http://europepmc.org/abstract/MED/27127180
http://europepmc.org/abstract/MED/24030381
http://europepmc.org/abstract/MED/23099237
http://europepmc.org/abstract/MED/20334914
http://europepmc.org/abstract/MED/23831921