Editor's Note: In this feature from Stockpickr, we highlight lists of stocks that have made new highs, lows or seen other unusual activity.

Rising on Unusual Volume: Dade Behring Holdings ( DADE) vaulted 33% on trading more than 15 times its average three-month volume Wednesday after the clinical diagnostic instrument maker agreed to be acquired by Siemens ( SI) for $77 a share in cash. Shares advanced $18.35 to $74.26.

52-Week Highs: Dade Behring also hit a 52-week high.

Biggest % Gainers: BladeLogic ( BLOG) skyrocketed 46% after the data-center automation-software company's initial public offering . The company sold 3.94 million of the 5 million shares. Underwriters have an option for another 750,000 shares. Shares advanced $8.07 to $25.07.

52-Week Lows: GPC Biotech ( GPCB) plummeted 35% after a Food and Drug Administration advisory panel recommended that the agency wait for more information before approving its prostate-cancer drug satraplatin. The news sunk shares of partner Spectrum Pharmaceuticals ( SPPI), which has some commercialization rights, as well as Germany-based GPC, which declined $7.20 to $13.16.

Biggest % Losers: GPC Biotech also hit a 52-week low.

Stocks With Unusual Option Activity: Gas pipeline operator Williams Cos. ( WMB) was experiencing unusual option activity. Senior Vice President Ralph A. Hill reported in a Securities and Exchange Commission filing Wednesday that he exercised options for 51,850 shares of common stock under a prearranged trading plan, according to the Associated Press. The shares, costing between $9.93 to $28.98 apiece, were then sold for $35.25 apiece. Shares closed up 15 cents to $33.31.

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