Stock futures slipped Wednesday night after the Dow Jones Industrial Average posted a second day of losses and rising oil prices kept traders on edge. Dow futures fell 294 points, or 0.6%. S&P 500 futures lost 0.6%, while Nasdaq 100 futures also dropped 0.6%. The market came under pressure in extended trading as oil prices continued their ascent: West Texas Intermediate futures were last up about 5%. In the regular session, the S&P 500 and the 30-stock Dow declined, while the Nasdaq Composite