specialized list construct. suggestions?

DocBook offers seven kinds of lists, but none that quite fit this bill: 
I'm looking for a list with a content model that is a rough equivalent 
to a <em><li/></em> followed by li+. That is, a list where a processing 
application is to assume that the first list item is something to be set 
apart from the others through whatever capabilities a given platform 
offers. Has anyone ever heard of such an animal in any DTD or schema 
that might serve as a model for me?

thanks,

Bob DuCharme          www.snee.com/bob           <bob@ 
snee.com>  "The elements be kind to thee, and make thy
spirits all of comfort!" Anthony and Cleopatra, III ii