PubMed Central is the largest repository of biomedical literature. This community aims to bring together semantic annotation data for the open access full text subset of pubmed central. 

For the 2012 dataset please visit https://zenodo.org/record/376814#.WYhqvFN96uU

http://biotea.github.io

for the 2012 dataset please visit https://zenodo.org/record/376814#.WYhqvFN96uU