http://europepmc.org/abstract/MED/16014569
http://europepmc.org/abstract/MED/23091097
http://europepmc.org/abstract/MED/26053404
http://europepmc.org/abstract/MED/9288106
http://europepmc.org/abstract/MED/22674506
http://europepmc.org/abstract/MED/21993670
http://europepmc.org/abstract/MED/22952040
http://europepmc.org/abstract/MED/24920063
http://europepmc.org/abstract/MED/22158541
http://europepmc.org/abstract/MED/26675346
http://europepmc.org/abstract/MED/23502782
http://europepmc.org/abstract/MED/23585524
http://europepmc.org/abstract/MED/27199251
http://europepmc.org/abstract/MED/10023947
http://europepmc.org/abstract/MED/9892178
http://europepmc.org/abstract/MED/25480502
http://europepmc.org/abstract/MED/24584352
http://europepmc.org/abstract/MED/23415222
http://europepmc.org/abstract/MED/10397742