NEW YORK (MarketWatch) — U.S. stocks recorded solid gains on Thursday, buoyed by a rebound in oil prices, deal news and upbeat quarterly earnings, pushing the S&P 500 and Dow industrials into positive territory for the year. Crude oil prices swung higher, gaining 4% and reclaiming the $ 50-a-barrel level. In merger news, Pfizer announced it would buy Hospira Inc. for $ 16 billion. The S&P 500 SPX, +1.03% closed 21 points, or 1%, higher at 2,062.50, with broad-based gains across all ten main sectors. A jump in oil prices lifted energy and materials stocks, while Pfizer deal news boosted healthcare stocks. The Dow Jones Industrial Average DJIA, +1.20% jumped 212 points, or 1.2%, to 17,885. The Nasdaq Composite COMP, +1.03% ended the day up 48 points, or 1%, at 4,765.