I am developing specialized database on some desease microarray experiments. The initial data is retreived from NCBI and ArrayExpress databases. The problem is that sample attributes sometimes specify similar or same things but in different manners: as cell and tissue names, desease names, age, ethnicity of donor, ect. Where do I find conventions for naming experiment sample attributes?
It turns out that ArrayExpress itself uses various ontologies (dictionaries structured as trees) available at Ontology Lookup Service when it processes users' search queries. Experimental Factor Ontology is the precisely one I was searching for.
Medical Subject Headings (MeSH) dictionary turned out to be handy as well.