1 5 0 http://purl.obolibrary.org/obo/OGMS_0000020 symptom 'symptom' SubClassOf 'data item' 'symptom' SubClassOf 'clinical history' http://purl.org/ELECTRICA/000000072 Computerized tomography (CT) 'Computerized tomography (CT)' SubClassOf 'Imaging study' http://purl.org/ELECTRICA/000000073 CT head 'CT head' SubClassOf 'Computerized tomography (CT)' http://purl.org/ELECTRICA/000000074 Magnetic resonance imaging (MRI) 'Magnetic resonance imaging (MRI)' SubClassOf 'Imaging study' http://purl.org/ELECTRICA/000000075 MRI head 'MRI head' SubClassOf 'Magnetic resonance imaging (MRI)' http://purl.org/ELECTRICA/000000076 MRI spine 'MRI spine' SubClassOf 'Magnetic resonance imaging (MRI)'