Most people look forward to weekends. But lately, the stock market has been nervous on most Fridays, as the uncertainty in Europe raises the possibility of some new problem arising over the weekend. The latest data on the U.S. trade deficit supported fears about Europe, as exports to the European Union fell by more than 11% in April. Still, without any huge news, the markets were pretty quiet, and the Dow Jones Industrials (INDEX: ^DJI) overcame an initial drop of as much as 60 points to rise by about 14 points shortly after 10:45 a.m. EDT.

Among Dow stocks, Kraft Foods (NYSE: KFT) rose a bit after announcing that it would move its listing from the New York Stock Exchange to the Nasdaq later this month. Kraft said that listing fees on the Nasdaq were much less expensive. For now, Kraft will keep the same ticker, but after its split later this year, both its North American grocery division and its global snack foods business will take new ticker symbols.

McDonald's (NYSE: MCD) fell 1.5% after releasing May sales results that disappointed investors. Same-store sales only rose 3.3%, with a drop in Asian market results weighing on the entire company. By contrast, U.S. sales remain strong in light of new product offerings, and even Europe is holding up reasonably well, although the company cited austerity measures as potentially creating problems down the road. Rival Yum! Brands (NYSE: YUM) plunged more than 5%, as it, too, has depended increasingly on international sales for its growth.

Wal-Mart (NYSE: WMT), however, was a big winner, jumping more than 2% and hitting another 52-week high. Economic uncertainty has supported Wal-Mart stock lately, as investors apparently gravitate toward the dependable results that the retail giant has provided in past economic slowdowns. Despite the threat of ongoing fallout from its Mexican bribery scandal, Wal-Mart has proven incredibly resilient thus far even as its stock approaches all-time high levels.

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