matching on: any of a series of headers

Say I want to match on any one of these headers:

        Sender: nextppp(_at_)chinx1(_dot_)ThoughtPort(_dot_)COM
        Reply-To: bestserv-replies(_at_)antigone(_dot_)com
        X-Loop: TopTen(_at_)pobox(_dot_)com
        Subject: Read Receipt

If I save all those headers in a file, how can I use 'grep' to see  
if any of them exist in the current message?

Or is there another (better) way?

Right now I am using:

* ! ^(Sender: nextppp(_at_)chinx1(_dot_)ThoughtPort(_dot_)COM|\
        Reply-To: bestserv-replies(_at_)antigone(_dot_)com|\
        X-Loop: TopTen(_at_)pobox(_dot_)com|\
        Subject: Read Receipt)


but as it grows I desire to get it out of .procmailrc if possible.  

Thanks

TjL

--
        Tj Luoma (luomat(_at_)peak(_dot_)org)
                http://www.next.peak.org/~luomat
                        Awaiting Apple's NeXTStep