The S&P 500 rose 1.12% to 1,856.78 in afternoon trading Friday.
The Dow Jones Industrial Average was up 1.16% to 16,289.44, while the Nasdaq was up 1.02% to 4,307.01.
The yield on a 10-year Treasury bond rose 0.84% to 2.75%.
The price of gold was up 0.98% to $1,336.60 per ounce.
Anaheim drug maker Questcor Pharmaceuticals Inc. was up about 4% to $79.43, for a market value of $4.68 billion. The company is expected to report results for its fourth quarter and full year on Tuesday.
Irvine medical laser maker Biolase Technology Inc. was up about 11% to $3.39, for a market value of $118.80 million. The company announced on Monday the sale of its 25,000th dental laser. It also said last week that it signed an agreement to distribute Stratasys Inc.'s 3-D printers.