Tokyo stocks dropped slightly Wednesday morning as investors remained wary ahead of the release of U.S. inflation data later in the day. The 225-issue Nikkei Stock Average fell 106.89 points, or 0.27 percent, from Tuesday to 39,666.24. The broader Topix index was down 4.77 points, or 0.17 percent, at 2,749.92. The U.S. dollar moved little in the upper 151 yen range as investors refrained from active trading ahead of the U.S. consumer price index data for March, dealers said. At noon, the dollar fetched 151.75-76 yen compared with 151.72-82 yen in New York and 151.90-91 yen in Tokyo at 5 p.m. T…