http://europepmc.org/abstract/MED/23112547
http://europepmc.org/abstract/MED/10323885
http://europepmc.org/abstract/MED/8283788
http://europepmc.org/abstract/MED/9361177
http://europepmc.org/abstract/MED/8682594
http://europepmc.org/abstract/MED/20583607
http://europepmc.org/abstract/MED/8395678
http://europepmc.org/abstract/MED/14688025
http://europepmc.org/abstract/MED/7698570
http://europepmc.org/abstract/MED/10639144
http://europepmc.org/abstract/MED/1566048
http://europepmc.org/abstract/MED/20102718
http://europepmc.org/abstract/MED/23204322
http://europepmc.org/abstract/MED/11215737
http://europepmc.org/abstract/MED/9155713
http://europepmc.org/abstract/MED/2841597
http://europepmc.org/abstract/MED/22609129
http://europepmc.org/abstract/MED/9014854
http://europepmc.org/abstract/MED/10612810
http://europepmc.org/abstract/MED/20196079
http://europepmc.org/abstract/MED/7578594
http://europepmc.org/abstract/MED/20233436
http://europepmc.org/abstract/MED/12190185
http://europepmc.org/abstract/MED/7914949
http://europepmc.org/abstract/MED/7493139
http://europepmc.org/abstract/MED/12117880
http://europepmc.org/abstract/MED/16456810
http://europepmc.org/abstract/MED/11487539
http://europepmc.org/abstract/MED/19026650
http://europepmc.org/abstract/MED/9777951
http://europepmc.org/abstract/MED/12438234
http://europepmc.org/abstract/MED/7923189
http://europepmc.org/abstract/MED/8150541
http://europepmc.org/abstract/MED/27656095
http://europepmc.org/abstract/MED/9663597
http://europepmc.org/abstract/MED/10661623