Wall Street was narrowly mixed Monday as lingering concerns about the economy offset better-than-expected sales from Wal-Mart Stores Inc. (WMT) and a flurry of acquisition activity.

In mid afternoon trading, the Dow rose 12.90, or 0.10 percent, to 12,666.39.

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Broader stock indicators fell. The Standard & Poor's 500 index was down 1.12, or 0.08 percent, at 1,447.27, and the Nasdaq composite index fell 3.95, or 0.16 percent, to 2,471.93.

Dow Jones industrial Wal-Mart rose after the world's largest retailer said it expected January same-store sales to rise 2.2 percent. Tempering the gain was its projection that sales performance is on track to deliver the lowest growth rate in more than 25 years.

Meanwhile, Wall Street absorbed a spate of acquisition and private equity deals — the largest amount since the start of the year. Triad Hospitals Inc. and Herbalife Ltd. received offers from private equity funds, while State Street Corp. agreed to buy Investors Financial Services Corp.

Investors had little reaction to new data that suggests continued economic growth, which could disrupt the Federal Reserve's plans to ease the economy this year. The Institute of Supply Management's non-manufacturing index, which covers the service sector, increased more than analysts were forecasting.

Wall Street is in a holding pattern now that the Fed's decision to hold rates is behind it, and the quarterly earnings season is largely over. Analysts say investors are now monitoring what central bankers might have to say in upcoming speeches and any corporate or economic news to find direction.

"We're just going to have a topsy-turvy market until investors figure out which direction to take," said Todd Leone, managing director of equity trading for Cowen & Co. "We're seeing some buying come back into the market because there still is a lot of money on the sidelines. And, all these deals announced are really helping the market out."

Treasuries largely shrugged off the ISM numbers. Bonds rose, with the yield on the benchmark 10-year Treasury note down to 4.81 percent from 4.82 percent late Friday.

Also squeezing stocks was a rebound in oil prices to near $60 per gallon as a cold snap hit the Northeast. However, oil reversed course and a barrel of light sweet crude was down 11 cents at $58.91 on the New York Mercantile Exchange.

The dollar was mixed against other major currencies, while gold prices up.

Wal-Mart rose 70 cents to $48.78 after it announced same-store sales topped its prior forecast for a 1 percent to 2 percent gain. The retailer said colder temperatures in January drove sales of seasonal items.

Triad Hospitals agreed to go private in a $4.7 billion deal from affiliates of CCMP Capital Advisors and Goldman Sachs affiliate GS Capital Partners. Shares surged $6.53, or 15.1 percent, to $49.80.

Nutritional supplement maker Herbalife said it received an acquisition proposal from private investment fund Whitney V LP that values the company at about $2.7 billion. The company said it is reviewing the offer, and its shares spiked $6.80, or 20.6 percent, to $39.90.

Billionaire financier Carl Icahn made a $2.43 billion offer for auto parts supplier Lear Corp. Shares jumped $4.21, or 12.1 percent, to $39.88.

Vornado Realty Trust increased its acquisition offer for building owner and manager Equity Office Properties Trust to $23.24 billion. Vornado dipped 33 cents to $125.02, while shares of its target fell 1 cent to $55.37.

State Street shares fell $4.57, or 6.4 percent, to $67.18 after the custody bank said it would buy Investors Financial Services for about $4.5 billion in stock. The deal, which comes as rivals Mellon Financial Corp. and Bank of New York Corp. plan to combine, sent shares of IFS up $12.93, or 27.5 percent, to $59.88.

IPod maker Apple Inc. and Apple Corps, the guardian of The Beatles' music resolved their long dispute on Monday about who has the right to the Apple trademark, and could be the first step in permitting downloads of the band's music. Apple shares rose 6 cents to $84.81.

Advancing issues led decliners by 4 to 3 on the New York Stock Exchange, where volume came to 719.4 million shares.

The Russell 2000 index of smaller companies was down 3.29, or 0.41 percent, at 806.13. The index surpassed the 800 mark for the first time last week.

Overseas, Japan's Nikkei stock average closed down 1.15 percent. At the close, Britain's FTSE 100 was up 0.11 percent, Germany's DAX index fell 0.17 percent, and France's CAC-40 was up 0.07 percent.

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