U.S. stocks are mostly higher in midday trading as negotiators continue to work toward a solution to Greece's debt problems.
Chinese stocks dropped 7 percent Friday as fears spread that a yearlong rally there has gotten overheated. The market is still up more double over the past year.
Nike jumped 5 percent after reporting results that beat analysts' estimates. Chipmaker Micron plunged 18 percent after its results fell far short.
The Dow Jones industrial average was up 90 points, or 0.5 percent, at 17,980 as of 11:45 a.m. Friday on Wall Street.
The Standard & Poor's 500 was up two points, or 0.1 percent, to 2,104.
The Nasdaq gave up 19 points, or 0.4 percent, to 5,092.
Bond prices fell. The yield on the 10-year Treasury note rose to 2.47 percent.