A handful of healthcare REITs have been on the upswing, as recent improvements in occupancy rates and their ability to restructure leases with facility operators have buoyed the share prices of several companies in the subsector. Analysts are taking note of the improvements. Take a look at three healthcare REITs that have received analyst upgrades this week. Sabra Health Care REIT Inc. (NASDAQ:SBRA) is an Irvine, California-based healthcare REIT that has 426 U.S. properties in its investment por