Shares of

Impax Laboratories

(IPXLE)

were among the worst-performing health-related stocks Friday, falling 23% after the company said its stock would be delisted from the Nasdaq market Monday morning.

The pharmaceutical company, which hasn't filed its 2004 annual report or its 10-Q report for the period ending March 31, 2005, said that its inability to submit its financials with the

Securities and Exchange Commission

in a timely manner left it in violation of Nasdaq's listing rules. The delisting notice contained a provision for relisting if the company can submit its filings within 90 days and demonstrate compliance with listing requirements. "Assuming it is able to meet this schedule, Impax believes this provision will expedite the relisting process," the company said. Shares in Impax will be quoted in the Pink Sheets beginning Monday and its ticker symbol will revert back to IPXL. Shares were trading down $3.29 to $10.82.

Bio-Rad Laboratories

(BIO) - Get Report

fell 7% after the company posted a year-over-year decline in second-quarter earnings. The maker of life-science research products reported earnings from continuing operations of $18.4 million, or 69 cents a share, on sales of $291.3 million. A single-analyst estimate tracked by Thomson First Call called for earnings of 72 cents a share on sales of $293.3 million. A year ago the company reported earnings from continuing operations of $20.3 million, or 76 cents a share, on sales of $260.5 million. Shares were trading down $4.41 to $57.64.

Shares of

Microtek Medical Holdings

( MTMD) fell 11% after the company posted second-quarter results and cut its full-year outlook. The maker of infection control and safety products posted earnings of $2.2 million, or 5 cents a share, on sales of $34.5 million. Results included losses of about $156,000, which was related to the closure of its manufacturing operations in Gurnee, Illinois. A single analyst was expecting a profit of 6 cents a share on sales of $35 million. A year ago the company reported earnings of $1.7 million, or 4 cents a share, on sales of $30.2 million. Looking ahead, Microtek now expects 2005 earnings of 20 cents a share on sales of $137 million to $138 million. Previously, the company said it would earn 23 cents to 25 cents a share on sales of $137 million to $142 million. The single-analyst estimate called for earnings of 23 cents a share. Shares were trading down 43 cents to $3.56.

AtriCure

(ATRC) - Get Report

rose 19% on its first day of trading as a public company. The maker of surgical devices sold 4 million shares in its initial public offering at $12 apiece, resulting in gross proceeds of about $48 million. Thomas Weisel Partners and AG Edwards co-managed the deal. Shares, which priced at the low end of their expected range of $12 to $14, were recently trading up $2.29 to $14.29.

Other health care volume movers included

Pfizer

(PFE) - Get Report

, down 27 cents to $26.33;

Teva Pharmaceutical

(TEVA) - Get Report

, up 60 cents to $33.60;

Protein Design Labs

(PDLI) - Get Report

, up $1.63 to $27.54;

Amgen

(AMGN) - Get Report

, down 73 cents to $81.95;

Merck

(MRK) - Get Report

, up 43 cents to $30.77;

Elan

(ELN)

, down 14 cents to $7.69;

Johnson & Johnson

(JNJ) - Get Report

, down 53 cents to $63.62;

StemCells

(STEM)

, down 3 cents to $5.67; and

Schering-Plough

( SGP), down 12 cents to $21.09.