Shares of On Assignment Inc. gained 8 percent on Friday after the specialty staffing firm said its first quarter profit jumped 54 percent on strong growth in all the health care and technology industries it serves.

After the markets closed on Thursday, the Calabasas company reported net income of $5.4 million (14 cents a share), compared with $3.5 million (9 cents) in the same period a year earlier. Revenue rose 29 percent to $167 million.

On Assignment places professionals in life science, health care, information technology and engineering positions. Last month it announced plans to buy Virginia technology staffing firm Apex Systems.

Excluding acquisition-related costs, net income was 18 cents a share. Analysts on average expected adjusted net income of 16 cents on revenue of $163 million, according to Bloomberg.

“We had an excellent first quarter of 2012 … each of our four operating segments generated double-digit revenue growth year-over-year,” said Chief Executive Peter Dameris in a statement.

On Assignment said it expects second-quarter earnings to be in the range of 20 to 22 cents a share.

Shares closed up $1.45, or 8 percent, to $18.98 on the Nasdaq.