The Blood Center of Wisconsin and Tomah Memorial Hospital need help to meet a growing demand for blood.  According to Blood Center Account Representative Dan Gordon, officials are asking residents to donate blood this Thursday, January 10 from one to six p-m at Tomah Memorial Hospital.  Gordon says the number of donors has dropped over the last couple of drives.  Gordon says the Blood Center of Wisconsin – -which is the sole provider of blood to area hospitals, including Tomah Memorial and the Tomah V-A Medical Center – -needs nearly eight-hundred donors every day statewide to help maintain supplies.  Donors can call Tomah Memorial Hospital at 374-6623 to schedule an appointment, although walk-ins are welcome.   Donors must be at least seventeen- years -old, although sixteen-year-olds can donate with parental consent.