http://europepmc.org/abstract/MED/23856246
http://europepmc.org/abstract/MED/8590778
http://europepmc.org/abstract/MED/24335104
http://europepmc.org/abstract/MED/29386642
http://europepmc.org/abstract/MED/23396385
http://europepmc.org/abstract/MED/8182933
http://europepmc.org/abstract/MED/1461658
http://europepmc.org/abstract/MED/23044976
http://europepmc.org/abstract/MED/22573403
http://europepmc.org/abstract/MED/8417784
http://europepmc.org/abstract/MED/1390218
http://europepmc.org/abstract/MED/8321049
http://europepmc.org/abstract/MED/25743686