http://europepmc.org/abstract/MED/27091358
http://europepmc.org/abstract/MED/28481359
http://europepmc.org/abstract/MED/26928227
http://europepmc.org/abstract/MED/25174276
http://europepmc.org/abstract/MED/23435014
http://europepmc.org/abstract/MED/26554828
http://europepmc.org/abstract/MED/27127140
http://europepmc.org/abstract/MED/25488749