(Clackamas, OR)  --  Police in Clackamas County are searching for a missing woman who suffers from dementia.  Authorities say 64-year-old Shirley Darlow was last seen yesterday around 4 p.m. near Jannsen Road and Southeast 90th.  Police say Darlow is about five feet tall and 100 pounds and was seen wearing a blue Adidas sweatshirt and jeans when she disappeared.  Anyone with information on her whereabouts is urged to contact police.