I steamed some clams seven days ago, and not all of them were eaten. I removed the shells and stored the flesh in a plastic container in the refrigerator. After seven days are they still safe to eat, since they were well cooked and refrigerated?
It's too risky for my tastes. Cooked seafoods (fin-fish and shellfish) are nearly a perfect growth medium for bacteria, so they have a particularly short shelf-life even when properly kept refrigerated -- perhaps three days. Here is a PDF from the Texas A&M Agricultural Extension Service with some useful guidelines.