http://europepmc.org/abstract/MED/20678218
http://europepmc.org/abstract/MED/24405536
http://europepmc.org/abstract/MED/21523797
http://europepmc.org/abstract/MED/20962861
http://europepmc.org/abstract/MED/27029036
http://europepmc.org/abstract/MED/22033490
http://europepmc.org/abstract/MED/24045501
http://europepmc.org/abstract/MED/24936872
http://europepmc.org/abstract/MED/24674452
http://europepmc.org/abstract/MED/20494930
http://europepmc.org/abstract/MED/22915641
http://europepmc.org/abstract/MED/20376084
http://europepmc.org/abstract/MED/23889083
http://europepmc.org/abstract/MED/23996483
http://europepmc.org/abstract/MED/21997850
http://europepmc.org/abstract/MED/24850867
http://europepmc.org/abstract/MED/27127180
http://europepmc.org/abstract/MED/24030381
http://europepmc.org/abstract/MED/20651083
http://europepmc.org/abstract/MED/28873367
http://europepmc.org/abstract/MED/20861910
http://europepmc.org/abstract/MED/21173122
http://europepmc.org/abstract/MED/24218139
http://europepmc.org/abstract/MED/23039322
http://europepmc.org/abstract/MED/23926297
http://europepmc.org/abstract/MED/21886174
http://europepmc.org/abstract/MED/19657110