State regulators rejected Tenet Healthcare Corp.'s plans to build a research hospital in Palm Beach Gardens that was to partner with the nearby Scripps Research Institute. The Agency for Health Care Administration denied the application by the hospital company (NYSE: THC) on Thursday. The application was initially approved, but Jupiter Medical Center and West Palm Hospital, part of HCA (NYSE: HCA), won a challenge before an administrative law judge that overturned the approval. The May ruling stated there was no need for the 80-bed Florida Regional Medical Center in the area because there is plenty of capacity at existing hospitals.