Wall Street slightly higher; biotechs cap gains

Wall Street was slightly higher in volatile trading on Thursday as a decline in biotech stocks offset gains in energy shares. The Nasdaq biotech sector was down 3.5 percent, with Celgene's 4.8 percent fall weighing the most. At 11:05 a.m. ET (1605 GMT), the Dow Jones industrial average was up 33.83 points, or 0.21 percent, at 15,978.29, the S&P 500 was up 7.47 points, or 0.4 percent, at 1,890.42 and the Nasdaq Composite index was up 34.00 points, or 0.76 percent, at 4,502.17.