(Portland, OR)  --  A bicyclist is hospitalized with critical injuries after being struck by a car near Hillsboro.  Police say the 28-year-old man was riding his bike in the middle of the roadway on Tualatin Valley Highway east of Southwest 331st Avenue last night when the vehicle struck him.  The driver reportedly stayed at the scene to cooperate with investigators.  Police say the bicyclist was not wearing a helmet.