Life-sciences specialist Thermo Fisher Scientific (NYSE:TMO) reported first-quarter earnings this morning that were ahead of the consensus estimates of Capital IQ analysts, but ended up issuing guidance for the full year that was a bit of a mixed bag.

Thermo Fisher reported revenues for the three months ending on March 30 of $3.19 billion, up more than 4% from the same period, when it recorded revenues of $3.06 billion and ahead of analysts' expectations of $3.17 billion. The life sciences leader recorded profits of $336.2 million, or $0.93 per share, up 24% from the $0.75-per-share profit it generated last year and firmly outpacing the $0.86 Wall Street was anticipating.

Yet when it offered up guidance for 2013, that's when Thermo Fisher had to mix things up. It tightened up its revenue range, lifting the lower end of its full-year expectations, but lowered its range of expected per share profits.

Thermo Fisher now expects to record revenues between $12.84 billion and $13.00 billion, compared with previous guidance of $12.80 billion to $13.00 billion, while per-share profits are now forecast to come in at $5.27 to $5.39 compared with its prior suggestion of $5.32 to $5.46 per share.

Noting that the guidance didn't take into account its acquisition of Life Technologies (UNKNOWN:LIFE.DL), Thermo Fisher President and CEO Marc N. Casper said:

We're pleased with our solid first quarter results, with good performance on the top line. We also extended our track record of strong adjusted EPS growth, delivering a 17% increase year over year. Although the macro environment played out at the lower end of our expectations, our teams executed well to continue our growth momentum into 2013.

With revenue of $13 billion annually, Thermo Fisher has 39,000 employees and serves the pharmaceutical and biotech industries as well as hospitals and clinical diagnostic labs, universities, research institutions, and government agencies.

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