I had to run into town this morning to get some things I forgot. When you come into town you go from 70 to 45 to 35 to 25 mph. You also go across a bridge over the Missouri river, which is the 35mph section. As I was coming off the bridge into the intersection there is a Stop sign on the left and right. I saw this small silver car coming from the right, the driver did not even stop, but went right through making a left turn right in front of me! I'm driving our 1 ton truck. I literally was standing on my brake with both feet, both arms braced for impact and thinking this is going to hurt like heck. I was able to stop before impact. I was so close I could not see the window ledge on the drivers door over the hood of the truck. The other driver, an elderly woman, barely even looked at me and kept going. I was able at the last second to lay on my horn. No response. My heart was pounding so hard my chest hurt and I was pushing so hard against the steering wheel my neck hurts now. All I could think of is if I had hit her I could have caused her death. She would have gotten the full impact of the front end. Talked to a fellow EMS provider and told her what happened and she said the same thing. Scared the daylights out of me.