Is there any way to next an "or" function within sumproduct?

I have about 1000 lines of data representing individual cases. I want to
create a formula that uses 3 columns A, B and C: Return the # of cases that
demonstrate a value greater than x in column A or y in column B. In
addition, each must also have a "1" in column C to be included. those that
have meet criteria in both column A and B should be counted only once.

anand