If an apple a day keeps the doctor away, then an Apple a quarter may well be a standing order for a bull market prescription. As Fool tech analyst Eric Bleeker noted earlier today, tech stocks across the board have helped pull the Dow Jones Industrials (INDEX: ^DJI) higher. And even though Apple isn't among its components, the Dow is following the rest of the market up, rising 46 points to 13,048 despite some choppiness related to the Fed's latest pronouncement on rates and the economy.

Virtually forgotten in the Apple haze was the fact that other companies reported earnings as well. Boeing (NYSE: BA) jumped more than 4.5% after announcing a 58% surge in profits in the first quarter, with huge aircraft sales and even a modest jump in its defense business revenue contributing to a big bottom-line beat. Even better, the aerospace giant boosted its guidance for full-year 2012 profits by $0.10 per share.

American Express (NYSE: AXP) also rose almost 2%. Although AmEx didn't have any big news today, Fool contributor Tim Beyers noted yesterday that the card company has done an excellent job tying into social-media companies to provide deals (which happen to require an AmEx card to play). If AmEx can sign up a new generation of cardholders, then its social-media moves will have been well worth the effort.

Finally, Pfizer (NYSE: PFE) rose again as investors are apparently speculating over whether the bigger-than-expected $11.85 billion windfall from the sale of its infant-nutrition unit could lead to higher dividends or share buybacks. Such a move could boost shares in the short run, but over the long haul Pfizer will need to prove that it can overcome patent-cliff challenges and boost ongoing sales through new drugs.

Earn, baby, earn
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