The Clinical Measurement Ontology (CMO), Measurement Methods Ontology (MMO), and Experimental Condition Ontology (XCO) are currently being developed at the Rat Genome Database. For more information about these vocabularies please see Shimoyama et al. Three ontologies to define phenotype measurement data. Front Genet. 2012;3:87. Epub 2012 May 28 or contact us (http://rgd.mcw.edu/contact/index.shtml).
The amount of retinol in a specified volume of plasma, the fibrinogen-containing fluid portion of the blood in which the particulate components are suspended. Retinol is a 20-carbon primary alcohol in any of several isomers that is the form of vitamin A found in mammals and that can be converted to the metabolically active forms retinal and retinoic acid.