RETRACTED: Swimming exercise increases the level of nerve growth factor and stimulates neurogenesis in adult rat hippocampus

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy).This article has been retracted at the request of the Editors.The authors acknowledge there are serious errors in the figures. Apologies are offered to the readers of the journal that this was not brought to the Editors' attention during the peer review process.