dropdownlist items find by partial value

To find an item (and select it) in a dropdownlist using a value we simply do

dropdownlist1.Items.FindByValue("myValue").Selected = true;

How can I find an item using partial value? Say I have 3 elements and they have values "myValue one", "myvalue two", "myValue three" respectively. I want to do something like

dropdownlist1.Items.FindByValue("three").Selected = true;

and have it select the last item.