Tokyo stocks opened lower Thursday as technology shares tracked overnight declines by their U.S. counterparts, while export-oriented issues were sold as the yen strengthened against the U.S. dollar. In the first 15 minutes of trading, the 225-issue Nikkei Stock Average fell 406.87 points, or 1.10 percent, from Wednesday to 36,640.74. The broader Topix index was down 15.47 points, or 0.59 percent, at 2,618.02. On the top-tier Prime Market, decliners were led by insurance, bank and transportation equipment issues. At 9 a.m., the dollar fetched 143.33-34 yen compared with 143.70-80 yen in New Yor…