Friday's Health Winners & Losers

Updated from 2:26 p.m. EST with new stock prices

Earnings, regulatory and government actions and generic-drug strategy all factored into a fairly positive day for health stocks Friday.

Medical device maker Intuitive Surgical(ISRG Quote) said Thursday post-close that fourth-quarter net income more than doubled to $49.2 million, or $1.24 a share, from $23.6 million, or 62 cents a share, a year ago. Revenue increased 68% to $189.4 million from $112.6 million in the year-ago quarter, driven by higher use and sales of the da Vinci Surgical System. Analysts polled by Thomson Financial had estimated profit would be $1.04 a share on revenue of $175.9 million. Shares were up a whopping $51.61 on Friday, or 20.3%, to $305.61.

Also on the uptick, Affymetrix(AFFX Quote) said Thursday post-close that net income climbed to $12.8 million, or 17 cents a share, from $8.7 million, or 13 cents a share, in the comparable year-ago quarter. The company reported earning 20 cents a share when restructuring charges are factored out, on revenue of $107.6 million. ...