http://europepmc.org/abstract/MED/1341278
http://europepmc.org/abstract/MED/8180579
http://europepmc.org/abstract/MED/7965884
http://europepmc.org/abstract/MED/1459726
http://europepmc.org/abstract/MED/2021541
http://europepmc.org/abstract/MED/26934577
http://europepmc.org/abstract/MED/8453633
http://europepmc.org/abstract/MED/24292195
http://europepmc.org/abstract/MED/27693639
http://europepmc.org/abstract/MED/19628422
http://europepmc.org/abstract/MED/2183872
http://europepmc.org/abstract/MED/27050151
http://europepmc.org/abstract/MED/24224046
http://europepmc.org/abstract/MED/21798893
http://europepmc.org/abstract/MED/17767136
http://europepmc.org/abstract/MED/21798897
http://europepmc.org/abstract/MED/8887073
http://europepmc.org/abstract/MED/23619168
http://europepmc.org/abstract/MED/28481359
http://europepmc.org/abstract/MED/1403838
http://europepmc.org/abstract/MED/8253528
http://europepmc.org/abstract/MED/9772288
http://europepmc.org/abstract/MED/22294102