Technology shares rebounded in the afternoon, erasing most losses from a sharp morning drop that dragged down other sectors. The Dow Jones industrial average fell 473.66, 1.4 percent decrease, to 34,269.16. The broader Standard & Poor's 500 index fell 36.34, 0.9 percent down, to 4,152.09. The technology-heavy Nasdaq composite index fell 12.43, 0.1 percent below, to 13,389.43.