The top half of the stomach is the non-glandular part--it does not contain the acid-secreting cells and doesn't have a mucus coating like the lower (glandular) part does. The top part is sort of the hopper--brings the food in and then shoves it on down to the acid bath.
The study design seems a little confusing and I'd want to know what they meant by "ulcer scores improved" because that may or may not be relevant clinically. (as opposed to on a score sheet)
Seems like a whole bunch of bicarb and other buffers with a few other natural-sounding ingredients to differentiate it from plain old baking soda. If they were having to watch the serum bicarb levels (to ensure legality on the racetrack) then the amount of sodium bicarb in the product is probably pretty high.