convert from access

I have to remake PHP script (which full of Access SQL implementation) for
PostgreSQL. I have a some of strings like this:

SELECT memmod.item, memmod.oempartno, memmod.sdescr
FROM memmod WHERE (InStr(1, [item], '".$edtPartNo."'));";

How can I convert this string for PostgreSQL?

--
-----------------
Sergei A. Karasiov
serge@mediatech.ru