5. The system of claim 1 wherein the at least one negation rule comprises a prefix negation rule comprising that a prefix negation term appear before the particular word in a same sentence as the particular word within the selected proximity.
5. The system of claim 1 wherein the at least one negation rule comprises a prefix negation rule comprising that a prefix negation term appear before the particular word in a same sentence as the particular word within the selected proximity. 6. The system of claim 5 wherein the at least one negation rule comprises a suffix negation rule comprising that a suffix negation term appear after the particular word in the same sentence without the prefix negation term within the selected proximity.