http://europepmc.org/abstract/MED/17360030
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http://europepmc.org/abstract/MED/29185262
http://europepmc.org/abstract/MED/24037752
http://europepmc.org/abstract/MED/7665253
http://europepmc.org/abstract/MED/29279289
http://europepmc.org/abstract/MED/16256179
http://europepmc.org/abstract/MED/9159349
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