MEDecision ( MEDE) shares tumbled more than 40% after it issued disappointing guidance. The Wayne, Pa.-based company, which makes health care software, expects to bring in fourth-quarter revenue between $10.3 million and $10.6 million, which reflects lower-than-expected license revenue. Shares were losing $3.97 to $5.71.

Therma-Wave, ( TWAV), which makes systems for semiconductor manufacturing, soared nearly 29% after KLA-Tencor ( KLAC) agreed to buy it for $75 million, or $1.65 a share -- a premium to the Fremont, Calif.-based company's $1.25 closing price Friday. Therma-Wave shares were rising 36 cents to $1.61. KLA was up 20 cents to $50.35.

Seattle Genetics ( SGEN) surged after the drugmaker struck a deal with biotech giant Genentech ( DNA) to develop a blood cancer drug called SGN-40. Genentech will pay the Bothell, Wa., company $60 million upfront, as well as potential milestone payments of more than $800 million and royalties. Seattle Genetics shares were up $1.43, or 27%, to $6.72. Genentech shares were dipping 18 cents to $83.50.

8x8 ( EGHT) jumped after the VoIP company said the subscriber base for its Packet8 services grew by more than 1,000 businesses in the fourth quarter, taking the total to more than 6,000. The Santa Clara, Calif., company also unveiled new technology at the Las Vegas Consumer Electronics Show -- a phone adaptor with an embedded LCD screen that can turn standard landline phones into videophones. Shares were gaining 27 cents, or 21.6%, to $1.52.

Signalife ( SGN) shot up after the Greenville, S.C.-based company said it had completed its cardiac vest product, which allows for precise ECG monitoring. The company will now submit the vest for accelerated FDA approval. Shares were up 22 cents, or 20.8%, to $1.28.

Bodison Biotech ( BBC) gained after the China-based maker of pesticides and fertilizers estimated it had earned about $12.9 million on $43 million in revenue last year, up from a profit of $7.4 million on sales of $31 million in 2005. Shares were adding 74 cents, or 16.4%, to $5.26.

IntraLase ( ILSE) a maker of equipment for laser-eye surgery, was up after it agreed to be bought by rival Advanced Medical Optics ( EYE) for $808 million, or $25 a share. The Irvine, Calif., company was rising $2.24, or 10.1%, to $24.47. Advanced Medical shares were essentially unchanged.

CanArgo ( CNR) dropped after the oil-drilling company announced delays for two of its Georgian test sites. Shares were off 20 cents, or 15.4%, to $1.10.

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