But it is active only in embryos.

可是它仅仅在晶胚中才具有活性。

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The discovery, published in the latest issue of Science, counters the traditional view that, in order to conserve energy, these animals were active only by day, leaving the night to small mammals.

这项与传统观点截然不同的发现刊登在最近一期的《科学》杂志上——传统的观点认为，为了保存能量，肉食恐龙只在白天活动，而把夜晚留给了那些小型的哺乳动物。

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Only if you take an active part in physical activity will you be able to keep fit and stay healthy.

你只有积极参加体育锻炼，才能保持身体健康。

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Professor Rauschecker says large parts of the visual cortex became active during the sound and touch tests, but only in the blind people.

VOA: special.2010.10.13

Lechuga-Ballesteros' group hunted for a recipe for dried insulin, a daunting trick because insulin is biologically active only in a liquid state.

FORBES: The Impossible Made Possible

The figure of 2.3 million which puts it at second place in our list includes active forces only - not civilian staff, like the US figure.

BBC: Which is the world's biggest employer?

Gone from last year: Lance Armstrong (our list is for active athletes only), White (now that we're a year past the 2010 Winter Games), Ohno (ditto), and NBA stars Kevin Garnett, Dwyane Wade and Kobe Bryant (probably just random, though Wade's stature decreased a tad with LeBron James joining his team, and Garnett is another year older).

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