Supporting a load bearing wall

The floor/roof loads above will be a bigger unknown than the ceiling itself. The wall MAY be replacable with properly sized beam/column combinations but you will need to have a design professional look for adauate footing size, calculate floor loads (and roof loads if any), and size the beam/column system to support ALL of the loads now carried by the wall. If you have access to the origional floor and roof framing plans they will be a great help, otherwise someone will need to do some investigating to make thoes design judgements.
In 23 years working as a building inspector I'v seen way too many structural problems caused by inadaquate beam installations, Its worth the time and money to do it right.
Good Luck.