Shares of

Martek Biosciences

( MATK) were among the best-performing health-related stocks Wednesday, jumping 14% after the maker of nutritional oils posted better-than-expected second-quarter results.

The company reported late Tuesday that it earned $6.3 million, or 19 cents a share, on revenue of $70.2 million. Analysts polled by Thomson First Call expected earnings of 16 cents a share on revenue of $67.9 million. During the year-earlier quarter, the company earned $3.4 million, or 11 cents a share, on revenue of $55.8 million. "Martek is rolling again with record revenues and cash generation, as well as near-record profits," the company said. "The future looks bright with strong interest from food companies and expanded international infant-formula sales." Shares were trading up $3.63 to $28.84.

Advanced Medical Optics

(EYE) - Get Report

rose 3% after the eye-surgery products company announced a

notes offering and stock-buyback plan. The company, which plans to sell up to $500 million in convertible senior subordinated notes due 2026, will use proceeds from the notes offering -- along with borrowings under its senior credit facility -- to fund a $500 million share-repurchase plan. The company also plans to purchase up to $100 million of its outstanding convertible notes. Shares were trading up $1.36 to $45.33.

Shares of

Vical

(VICL)

rose 4% after the biopharmaceutical company said it received accelerated access to a $2.6 million grant from the National Institute of Allergy and Infectious Diseases. The company plans to use the money for the continued preclinical development of its avian flu vaccine program. The company said it's also seeking additional funding that will be used to support human testing in a phase I trial. Shares were trading up 26 cents to $6.90.

Other health care volume movers included

Pfizer

(PFE) - Get Report

, up 31 cents to $24.15;

Elan

(ELN)

, up 28 cents to $16.11;

Charles River Labs

(CRL) - Get Report

, up 20 cents to $40.15;

Boston Scientific

(BSX) - Get Report

, down 24 cents to $20.29;

Amgen

(AMGN) - Get Report

, down 8 cents to $67.53;

UnitedHealth Group

(UNH) - Get Report

, up 44 cents to $46.62;

Merck

(MRK) - Get Report

, up 47 cents to $34.37;

Johnson & Johnson

(JNJ) - Get Report

, up 43 cents to $61.37;

Teva Pharmaceutical

(TEVA) - Get Report

, up 12 cents to $37.17; and

Bristol-Myers Squibb

(BMY) - Get Report

, up 10 cents to $24.96.