The Dow Jones Industrial Average on Thursday came off its worst levels of the session and turned positive in afternoon trade. The Dow was up about 23 points, or 0.1%, at 23,952, after sinking by as many as 394 points in late-morning trade. The S&P 500 index was down by less than 0.1% at 2,634, at last check, after hitting a low at 2,594, while the Nasdaq Composite Index was trading flat at 7,100, after touching a nadir at 6,991. Both the S&P 500 and the Dow retreated below their long-term, 200-day moving averages, which technical analysts tend to use as a gauge of an assets momentum. However, market participants say some opportunistic buying may occur after breaching such technical levels. There were few other catalysts powering the stock market’s attempt at a midday turnaround.