Upbeat start on Wall Street

A slew of merger news and a slide in oil prices were among the factors lifting stocks Monday morning, tempering concerns about Pfizer after it halted development of a key new drug.

The Dow Jones industrial average (up 31.64 to 12,225.77, Charts) added 0.3 percent in the early going, as did the broader Standard & Poor's 500 (up 4.23 to 1,400.94, Charts). The tech-fueled Nasdaq (up 12.80 to 2,426.01, Charts) composite added 0.5 percent.

The major gauges slipped Friday at the end of a tough week in which slowdown worries preyed on investors' confidence.

After the retreat, investors were willing to move back into stocks Monday, particularly technology, with the Nasdaq having been hit the hardest last week.

The morning brought a number of big company deals.

In the financial sector, Bank of New York (up $3.73 to $39.21, Charts) and Mellon Bank (up $2.30 to $42.35, Charts) announced a $16.5 billion deal the companies are calling a merger of equals.

Station Casinos (up $12.21 to $81.31, Charts) has received a $4.7 billion management-led buyout offer to go private.

And LSI Logic (down $1.04 to $9.52, Charts) said it will buy Agere Systems (up $2.31 to $20.10, Charts) for $4 billion.

Pfizer (down $3.78 to $24.08, Charts), a Dow stock, plunged 13 percent on news that it has stopped developing a new experimental cholesterol treatment because a study resulted in an unexpected number of deaths.

U.S. light crude oil for January delivery fell 74 cents to $62.69 a barrel in electronic trading.

The dollar recovered some after hitting a 20-month low versus the euro last week. The greenback also inched higher versus the yen.

Treasury prices fell, raising the yield on the benchmark 10-year note to 4.45 percent from 4.43 percent late Friday. Bond prices and yields move in opposite directions.

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