Tokyo stocks opened mixed Friday as technology shares were sold, tracking falls on Wall Street overnight, while rising oil prices boosted energy firms. In the first 15 minutes of trading, the 225-issue Nikkei Stock Average fell 150.96 points, or 0.39 percent, from Thursday to 38,656.42. The broader Topix index was up 6.88 points, or 0.26 percent, at 2,668.47. On the top-tier Prime Market, decliners were led by marine transportation and textile and apparel issues, while top gainers were mining, and oil and coal product issues. At 9 a.m., the U.S. dollar fetched 148.29-30 yen compared with 148.2…