Free access to biomedical literature resources including:* PubMed abstracts (about 22 million)* UKPMC full text articles (about 2.2 million of which over 400000 are Open Access)* Patent abstracts (over 4 million European US and International)* National Health Service (NHS) clinical guidelines* Agricola records (500000)* Supplemented with Chinese Biological Abstracts and the Citeseer database.UKPMC is based on PubMed Central (PMC) developed at the NCBI in the USA and is part of a network of PMC International (PMCI) repositories that also includes PMC Canada. It is supported by 18 funders of biomedical research including charities and government organizations in the UK Austria and Italy led by the Wellcome Trust. Reasons to use UKPMC as your primary biomedical information resource:* It is free comprehensive fast and reliable.* All of the abstracts and articles can be accessed through one search box.* You can sort the search results by publication date relevance or the number of times an article has been cited.* Links to public databases such as UniProt Protein Data Bank (PDBe) and the European Nucleotide Archive (ENA) are provided.* Through textmining technologies you can highlight and browse keywords such as gene names organisms and diseases.* Search 40000 biomedical research grants awarded to the 18000 PIs supported by the UKPMC funders.* Roadtest new tools based on UKPMC content in UKPMC Labs.* In UKPMC+ PIs supported by the UKPMC funders can link grants to publication information view article citation and download statistics and submit manuscripts.