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What: Shares of medical testing solutions specialist Quidel (Nasdaq: QDEL) got a clean bill of health today, jumping 14.7% on massive volume.

So what: This is a one-two combination: Quidel reported analyst-crushing third-quarter revenues with an adequately small net loss and also announced FDA clearance to sell a new line of fluorescent flu-virus detectors.

Now what: The Sofia flu tester was approved for European sales in August, so production lines are already rolling. Fellow diagnostic-equipment expert Alere (NYSE: ALR) also reported a fine quarter on Tuesday night, so it looks like hospitals aren't shy to invest in lab equipment these days. Investors were quick to jump to this conclusion as well, as Nanosphere (Nasdaq: NSPH) shares also gained nearly 10% on no news of its own.

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