The Apple of Wall St.'s eye

LONDON (CNNMoney.com) -- U.S. stock futures were stronger Tuesday after positive earnings reports, led by Apple Computer, lifted sentiment.

At 7:39 a.m. ET, Nasdaq futures were sharply higher, pointing to a positive open. The broader market, however, looked set for a tougher start.

Apple (Charts, Fortune 500) posted sharply higher revenue and earnings after the market close on Monday. The results handily beat Wall Street's estimates and shares of Apple were up more than 7 percent in pre-market trading Monday.

Chipmaker Texas Instruments (Charts, Fortune 500) also reported better than expected earnings even with a drop in revenue. But its shares lost more than 6 percent after it gave a fourth-quarter revenue target that is lower than the average analyst estimate.

But chemical maker DuPont (Charts, Fortune 500) beat forecasts as growth in all of its segments outside the United States offset weak domestic demand. Shares of the Dow component gained 2.5 percent in Frankfurt trading after the report.

Peter Cardillo, chief market economist for Avalon Partners, said so far earnings reports for the most recent quarter have shown strength, particularly in tech and industrial companies. That's helping to lift markets even in the face of rising oil prices and a sliding dollar.

"Obviously it's exporters and multinationals that are doing well due to the lower dollar," he said. "There's no question we have a murky outlook about the fourth and first quarters (of 2008), but as of now, the earnings are better than we were anticipating in terms of overall growth."

Another slew of corporate earnings is on tap Tuesday, including results Dow component AT&T (Charts, Fortune 500) before the openl, and online retail bellwether Amazon.com after the close.

In other corporate news, Countrywide Financial (Charts, Fortune 500), the nation's largest mortgage lender, announced a program Tuesday to refinance or modify up to $16 billion of its loans due to reset at higher payments through the end of next year.

Nike (Charts, Fortune 500) said it is buying British sports apparel maker Umbro for $582 million. The move is expected to help the U.S. giant expand its soccer presence.

In global trade, major markets in Asia also rebounded. Hong Kong's Hang Seng index added more than 3 percent. European stocks were higher in early trading. The dollar was lower versus the euro but it gained on the yen. BP (Charts) gained 2 percent in London trading even after the company reported lower earnings.