US STOCKS-Earnings, healthcare give Wall St sixth straight gain
* S&P 500, Nasdaq on six-day winning streak
* Netflix up after results; Facebook gains on upgrade
* Allergan soars as Ackman and Valeant bid for company
* Dow up 0.4 pct; S&P 500 up 0.4 pct; Nasdaq up 1 pct (Adds Gilead earnings, updates volume)
By Chuck Mikolajczak
NEW YORK, April 22 (Reuters) - U.S. stocks rose on Tuesday as a host of solid earnings reports, along with strength in the healthcare sector, helped lift the S&P 500 and Nasdaq to their sixth straight advance.
Netflix Inc surged 7 percent to $372.90 a day after reporting strong subscriber growth, a sign the trading favorite still had room to grow despite recent valuation concerns. With the day's gain, the stock moved to the plus side for the year after a 21 percent drop in March.
The S&P healthcare index, up 1 percent, was the best performer of the 10 major S&P sectors. Allergan Inc jumped 15.2 percent to $163.65 a day after activist investor William Ackman teamed up with Canadian drugmaker Valeant Pharmaceuticals International Inc to bid for the company. U.S.-listed Valeant shares gained 7.5 percent to $135.41.
A deal between Novartis and GlaxoSmithKline , in which the two traded over $20 billion worth of assets in an effort to cope with healthcare spending cuts and generic competition, also bolstered the healthcare sector. U.S.-listed shares of Novartis gained 1.3 percent to $86.56, while Glaxo rose 4.1 percent to $55.30. Continuación...