Minnesota State Board of Health button, c.1930.

Charles N. Hewitt, c.1900.

Charles N. Hewitt, tintype c.1860.

Minneapolis Board of Health member giving vaccinations, 1904. Vaccinations were often supplied to local health boards by the State Board of Health.

World War II "K-ration" issued to a Minnesota soldier, c.1941-1944. The K-ration, developed by and named for University of Minnesota physiologist Ancel Keys, provided soldiers in World War II with calorie-rich foods and psychological sustenance in the form of cigarettes.

Minnesota's first two American Indian nurses, Elizabeth Sherer and Josephine Parisien, c.1925. The Minnesota Department of Health started a Chippewa Nursing Service in 1923, hiring American Indian nurses to provide public health nursing services on reservations in northern Minnesota.

Civil War surgical instruments and case, 1861-1865. This kit used by a Fifth Minnesota Infantry Regiment surgeon, with its prominent amputation saws and scarificators for bloodletting, illustrates the reliance of physicians in the era before germ theory on "heroic" medical interventions.

The Mayo Clinic treats more than half a million people each year in Rochester, Minnesota, and in facilities in Florida and Arizona. MN90 producer Marisa Helms reports that the Mayo family philosophy of team-based patient care was established early on, and continues to be a hallmark of the world-famous hospital.