When more Vanderbilt University health clinics open next month at 100 Oaks Mall in Nashville, it could be a boon for businesses at the mall a few miles south of downtown, which has needed a shot in the arm for years. About 750 university employees will work there at least part-time, and 1,000 patients are expected to come through the 19 clinics each day. Vanderbilt's medical center agreed 18 months ago to lease 440,000 square feet of space at the mall. The university opened one clinic there last winter.