The Dow Jones Industrial Average Wednesday afternoon wiped away the lion's share of an opening 510-point drop as shares of Apple Inc. AAPL, +1.40% UnitedHealth Group Inc. UNH, +1.70% and International Business Machines Corp. IBM, +2.35% helped limit blue-chip losses. The Dow DJIA, +0.45% most recently was off 70 points, or 0.3%, at 23,957. Shares of Apple, UnitedHealth and IBM were among the best point gainers for the price-weighted equity gauge. The Dow had been down by as much as 2.1%, with Wall Street attributing the decline to mounting concerns about a full-fledged trade war erupting between China and the U.S. Those fears reemerged after China proposed retaliatory tariffs on 106 U.S. imports, including soybeans and airplanes, among others. The S&P 500 index SPX, +0.66% was trading in positive territory at 2,615, after also opening sharply lower, while the Nasdaq Composite Index COMP, +0.78% was up 0.3%, also erasing a sharp initial plunge.