Tokyo stocks dropped Monday as a wide range of issues were sold on global economic uncertainty fueled by escalating conflict in the Middle East, but the downside was capped as a weakening yen spurred buying on dips. The 225-issue Nikkei Stock Average ended down 290.75 points, or 0.74 percent, from Friday at 39,232.80. The broader Topix index finished 6.44 points, or 0.23 percent, lower at 2,753.20. On the top-tier Prime Market, decliners were led by pharmaceutical, air transportation, information and communication issues. The U.S. dollar notched a fresh 34-year high in the upper 153 yen zone i…