. . . . . . . . . . . . "[Only radioimmunoassays (RIAs) based on labelled antigen competition reached the required sensitivity for early pregnancy PAPP-A determinations; but they have a very short shelf life due to inherent tracer half-life and, in the case of PAPP-A, instability of the labelled antigen after three weeks.]. Sentence from MEDLINE/PubMed, a database of the U.S. National Library of Medicine."@en . . . . . "2014-02-25"^^ . . "Gene-disease associations inferred from text-mining the literature."@en . "DisGeNET evidence - LITERATURE"@en . "2014-10-02T12:36:18+02:00"^^ . . . . . . . . . . . "v2.1.0.0" . "v2.1.0" .