Your Query returns 9 Accession Numbers:

Query TermAccessionNCBI TaxonidSynonymsPhenotype (OMIM) *
ribosomal RNA operon AAF22014729459rrnA operon   
ribosomal RNA operon AAF22206535777
ribosomal RNA operon AAF19022474459
ribosomal RNA operon AAF19022641713
ribosomal RNA operon AAF190228138648
ribosomal RNA operon AAF23290840480
ribosomal RNA operon AAF32264435779
ribosomal RNA operon AAF373105179880rrnA   
ribosomal RNA operon AAF370119179881rrnA   

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* OMIM link based on symbol match for human and mouse.

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Text2Knowledge ... Yong Huang 2002