http://europepmc.org/abstract/MED/7918071
http://europepmc.org/abstract/MED/11301359
http://europepmc.org/abstract/MED/27029036
http://europepmc.org/abstract/MED/24045501
http://europepmc.org/abstract/MED/24674452
http://europepmc.org/abstract/MED/2657575
http://europepmc.org/abstract/MED/8217795
http://europepmc.org/abstract/MED/3295562
http://europepmc.org/abstract/MED/8057669
http://europepmc.org/abstract/MED/1574246
http://europepmc.org/abstract/MED/7947263
http://europepmc.org/abstract/MED/24850867
http://europepmc.org/abstract/MED/27127180
http://europepmc.org/abstract/MED/24030381
http://europepmc.org/abstract/MED/7512175
http://europepmc.org/abstract/MED/8194046
http://europepmc.org/abstract/MED/2642713
http://europepmc.org/abstract/MED/10627475
http://europepmc.org/abstract/MED/23708912
http://europepmc.org/abstract/MED/7927179
http://europepmc.org/abstract/MED/22753870
http://europepmc.org/abstract/MED/1991170
http://europepmc.org/abstract/MED/9305595
http://europepmc.org/abstract/MED/9593469
http://europepmc.org/abstract/MED/14737077
http://europepmc.org/abstract/MED/15474158
http://europepmc.org/abstract/MED/23926297
http://europepmc.org/abstract/MED/2668844
http://europepmc.org/abstract/MED/1536950
http://europepmc.org/abstract/MED/21909114
http://europepmc.org/abstract/MED/19657110
http://europepmc.org/abstract/MED/9379676