21.   Killing the adult ticks will interrupt the reproduction cycle, scientists said.

22.   No way, say scientists, who call such thinking a folk myth.

23.   Now it appears that equally nasty ice dwells amid the fire, says planetary scientist Alfred McEwen of the University of Arizona.

24.   Only about a dozen or so cell lines have been described in the scientific literature and fewer still are widely available in this country, scientists said.

25.   Pigs have been cloned for the first time using methods that may lead to an important new source of human-like organs for transplant, scientists said Wednesday.

26.   Raising new concerns about the technology used to copy life, scientists said Thursday that cloned mice are prone to striking cases of obesity.

27.   Since the immune system loses some of its power with aging, taking extra vitamin E could in effect rejuvenate those defenses, said the scientists.

28.   Statistically, the women would have been expected to die in less than a year without such treatment, the scientists said.

29.   Testing the Altropane technique on children can come only after ethics review boards are convinced that it is safe, said the scientists.

30.   That may now change, say scientists.

v. + scientist >>共 331
say 9.35%
include 4.78%
have 2.61%
divide 2.28%
intrigue 1.96%
baffle 1.74%
lead 1.30%
leave 1.30%
take 1.20%
bring 1.09%
say + n. >>共 862
official 10.72%
police 6.88%
spokesman 3.72%
no 3.22%
analyst 2.66%
report 2.47%
source 2.45%
trader 1.74%
goodbye 1.60%
thing 1.27%
scientist 0.14%
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