Health stocks followed the broader markets into a refreshing green spell on Thursday amid medical technology and diagnostics earnings.

Big biotechs Amgen ( AMGN) and Biogen Idec ( BIIB) were up trading up more than 2% each. Also Gilead ( GILD) and Genzyme ( GENZ) added 1.4% and 1.2% respectively.

In fact, every stock on the Amex biotechnology index, which was up 2.1% at 760.94, read green midday Thursday except for biotech behemoth Genentech ( DNA). Its shares were incidentally off by 0.4%, at $67.92.

Away from biotechs, Orthopedic product maker Orthofix International NV ( OFIX) said Thursday that its first-quarter profit fell to $3.6 million, or 21 cents a share, from $6.3 million, or 37 cents a share, in the year-ago period.

Revenue rose 9% to $128 million from $117 million, beating expectations of analysts polled by Thomson Financial who expected profit of 9 cents a share on revenue of $122.5 million. The beat prompted a 14.6% rise in the stock, to $35.25.

Also up, Natus Medical ( BABY) 6.5% to $20.94 after beating first-quarter earnings estimates and raising guidance. The newborn-care product maker said it earned $2.6 million, or 11 cents a share, up 73% from $1.5 million, and 7 cents a share, in the year-ago quarter. Revenue climbed 36% to $36.9 million, analysts surveyed by Thomson Financial were looking for 10 cents a share, on $35.5 million in revenue.

Natus also upped its first-quarter expectations to 72 cents a share on revenue of $162 million, from previous guidance of 70 cents and $161 million.

And Advanced Medical Optics ( EYE) said its first-quarter net profit was $6.9 million, or 11 cents a share, down from $12.1 million, or 20 cents a share, a year earlier. Factoring out acquisition and restructuring charges, the company earned 22 cents a share, on net sales to $303.7 million.

Analysts surveyed by Thomson Financial were looking for 22 cents a share, on revenue of $294.6 million. Shares rose 11.9% to $23.50.

Heading the other direction, laser device company Palomar Technologies ( PMTI) found its shares down 16.7% at $11.75, after reporting a net loss of $1 million, or 5 cents a share, vs. a profit of $5.9 million, or 30 cents a share, a year earlier. On an adjusted basis, the company earned 9 cents a share on revenue of $23 million, which was down from $31.5 million in 2007.

Analysts surveyed by Thomson Financial were looking for 7 cents a share on revenue of $28.7 million.

Medical technology company Hologix ( HOLX), which recently completed a 2-for-1 stock split, plummeted $6.02, or 20.1%, to $23.17 Thursday after the company aired its second-quarter results. Revenue climbed to $431 million from $181.1 million. Hologic reported net income of $56 million, or 22 cents a share a share -- and adjusted profit of $76.2 million, vs. $24 million a year prior.

Analysts surveyed by Thomson Financial were looking for $70.6 million, and 28 cents a share, on revenue of $418 million.

Also on the decline, drug development services company, PharmaNet ( PDGI), missed Wall Street's first-quarter views on loss of contract revenue. The company reported a loss of $10.1 million, or 53 cents a share, vs. a profit of $6.6 million, or 35 cents a share, a year prior. Revenue was $107.4 million, actually beating its part of the Thomson Financial consensus target of profit of 30 cents a share on $94.6 million.

The company lowered its full-year guidance to revenue between $390 million and $399 million from previous guidance of $401 million to $409 million.

Jeffries and Co. downgraded the stock to hold from buy and chopped its price target to $15 from $32. Robert Baird also downgraded it, to neutral from outperform, and lowered its price target to $24 from $33.

PharmaNet shares shed $6.70, or 28%, to $17.16 on Thursday.

Another analyst action, JMP Securities upped its price target for Sangamo BioSciences ( SGMO) -- a day after its earnings -- to $24 from $18. After opening 6 cents lower than the previous close, the company added 4.7%, to $13.35 in recent regular trading.

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