The top after-market NASDAQ stock market gainers on Thursday are: Immucor, Opnext, Ardea Biosciences, Audiovox Corp and United Community Banks. The top after-market NASDAQ stock market losers on Thursday are: Saba Software, XOMA, Xyratex, Conceptus and QuickLogic.

Gainers

Immucor, Inc. (NASDAQ:BLUD) shares surged 6.16 percent to $20.50 in post market trading, following better-than-expected second quarter earnings as lower costs and expenses offset a slight decrease in revenue. Net income rose to $21.1 million or $0.30 per share from $19.7 million or $0.28 per share in the same quarter last year.

 Opnext, Inc. (NASDAQ:OPXT) shares advanced 4.02 percent to $2.07 in aftermarket trading session. The stock has a 52 week low of $1.29 and 52 week high of $2.76 and has 89.89M outstanding shares.

Ardea Biosciences, Inc. (NASDAQ:RDEA) shares advanced 3.45 percent to $26.99 in aftermarket trading session. The company reported that it has achieved the primary and key secondary endpoints in a Phase 2b study of RDEA594 in combination with the current standard of care for the treatment of gout, allopurinol.

Audiovox Corp (NASDAQ:VOXX) shares advanced 3.02 percent to $8.40 in aftermarket trading hours. Its shares fell 4.12 percent to $8.15 in regular trading session.

United Community Banks, Inc. (NASDAQ:UCBI) shares advanced 2.97 percent to $2.08 in post market trading session. Its shares reiterated a “neutral” rating at Zacks Investment Research.

Losers

Saba Software, Inc. (NASDAQ:SABA) shares plunged 12.12 percent to $5.51 in aftermarket trading session as the company reported second quarter net loss and lowered its outlook for fiscal 2011.

XOMA Ltd. (NASDAQ:XOMA) shares declined 10.91 percent to $6.04 in aftermarket trading hours. The stock has a 52 week low of $2.24 and 52 week high of $12.60 and has 21.80M outstanding shares.

Xyratex Ltd. (NASDAQ:XRTX) shares declined 9.46 percent to $15.50 in post market trading session, following weaker-than-expected fourth quarter earnings and first quarter profit forecast.

Conceptus, Inc. (NASDAQ:CPTS) shares declined 5.59 percent to $12.50 in afterhours trading session. The company lowered its fourth quarter revenue guidance in the range of $36.3 million to $36.6 million from its earlier view of $39.0 million to $41.0 million.

QuickLogic Corp (NASDAQ:QUIK) shares declined 5.56 percent to $6.28 in after market trading session.