FORT LAUDERDALE, Fla. -- One of the largest health care systems in the country plans to set up nurse-staffed health clinics in as many as six Wal-Mart Supercenters, the Miami Herald has reported. The North Broward Hospital District will operate the locations to take care of simple medical needs with nurse practitioners who can write prescriptions. According to the district‘s website, it is the country‘s fifth largest health care system. That would make it the biggest player yet in the fledgling in-store clinic business, industry observers noted. Wal-Mart has clinics in 40 stores across in the country, including six in Florida, the newspaper reported.