Appendix.

Ontological and terminological resources mentioned in this article (all URLs are valid as of 9 July, 2006).

BFO	Basic Formal Ontology http://ontology.buffalo.edu/bfo/
ChEBI	Chemical Entities of Biological Interest http://www.ebi.ac.uk/chebi/
CPT	Current Procedural Terminology http://www.ama-assn.org/ama/pub/category/3113.html
CTV3	Clinical Terms Version 3 (formerly known as the Read Codes) http://www.nhsia.nhs.uk/terms/pages/readcodes_intro.asp
DM&D	Dictionary of Medicines and Devices http://www.dmd.nhs.uk/
DOLCE	Descriptive Ontology for Linguistic and Cognitive Engineering http://www.loa-cnr.it/DOLCE.html
EMTREE	EMTREE is Elsevier’s Life Science Thesaurus http://www.info.embase.com/emtree/about/
FMA	Foundational Model of Anatomy http://fma.biostr.washington.edu/
GALEN	Generalized Architecture for Languages, Encyclopedias and Nomenclatures in medicine http://www.opengalen.org/
GO	Gene Ontology http://www.geneontology.org/
ICD	International Classification of Diseases http://www.who.int/classifications/icd/en/
ICPC	International Classification of Primary Care http://www.globalfamilydoctor.com/wicc/
MeSH	Medical Subject Headings http://www.nlm.nih.gov/mesh/
MGED	Microarray Gene Expression Data Ontology http://mged.sourceforge.net/ontologies/MGEDontology.php
NCI Thesaurus.	NCI Thesaurus http://cancer.gov/cancerinfo/terminologyresources/
OBO	Open Biomedical Ontologies http://obo.sourceforge.net/
OPCS	Office of Population Censuses and Surveys Intervention Classification http://www.connectingforhealth.nhs.uk/interventionclassification
SNOMED	Systematized Nomenclature of Medicine http://www.snomed.org/
SNOP	Systematized Nomenclature of Pathology (superseded by SNOMED)
SUMO	Suggested Upper Merged Ontology http://ontology.teknowledge.com/
UMLS	Unified Medical Language System http://umlsks.nlm.nih.gov/ (cost-free license required)