Tokyo’s Topix stock index briefly climbed to an all-time high Thursday morning for the first time in 34 years on buying driven by hopes for robust earnings by Japanese exporters and financial issues. The 225-issue Nikkei Stock Average rose 86.02 points, or 0.21 percent, from Wednesday to 40,666.78. The broader Topix index was up 10.63 points, or 0.37 percent, at 2,882.81. The U.S. dollar fell slightly to the lower 161 yen range in Tokyo, after U.S. employment-related data released Wednesday indicated a potential slowdown in the labor market, raising expectations the Federal Reserve is on track…