The markets traded mixed during the midday as the civilian labor force contracted in January. The Dow rose 21 points to 12,671 while Nasdaq lost 2 points to 2388.

On the upside

Fourth quarter earnings for Altera (Nasdaq: ALTR) slipped due to higher costs but the results beat expectations and the chipmaker forecast first quarter results above estimates.

Intuitive Surgical (Nasdaq: ISRG) reported fourth quarter earnings that more than doubled to surpass expectations as sales rose.

CSK Auto (NYSE: CAO) received a purchase offer of approximately $350 million in stock from rival O'Reilly Automotive (Nasdaq: ORLY).

On the downside

Although Avid Technology (Nasdaq: AVID) reversed year ago losses, the company reported fourth quarter results below estimates and warned that 2008 would be a difficult year.

Fourth quarter earnings for Millipore (NYSE: MIL) rose but revenue fell short of expectations.

Digital River (Nasdaq: DRIV) reported higher fourth quarter earnings but the e-commerce software company provided first quarter guidance well below estimates.

In the broad market, advancing issues outpaced decliners by a margin of nearly 5 to 2 on the NYSE and by 7 to 5 on Nasdaq. The Russell 2000 which tracks small cap stocks rose 7 points to 720.