1.   If breathing stops, there is no oxygen getting to the brain and within three minutes the brains cells begin to die.

2.   At a late stage in development, these cells begin to separate.

3.   At the same time, the cells begin making too little collagenase, the enzyme that destroys excess collagen.

4.   A cell begins to reproduce uncontrollably.

5.   About half the embryos made with cumulus cells began developing normally, as did about one-fourth of the embryos created using oviduct cells.

6.   But they said it was too soon to know whether the baboon cells have begun to grow and function immunologically.

7.   But when experiences from the outside world begin to flow into the brain, cells begin to fire, and Hebbian patterns get stamped in.

8.   Deprived of oxygen and other nutrients in the blood, the brain cells begin dying.

9.   If one cell begins to move past another, the two cells will reorient themselves and try to draw closer together, checking the separation.

10.   In minutes, the starved brain cells begin to die.

n. + begin >>共 1326
company 1.92%
talk 1.47%
season 1.44%
trial 1.32%
government 1.26%
official 1.15%
people 1.01%
police 0.93%
work 0.90%
game 0.72%
cell 0.06%
cell + v. >>共 409
be 16.86%
have 5.47%
divide 3.10%
produce 2.91%
grow 2.37%
die 2.37%
become 2.23%
begin 1.65%
contain 1.55%
make 1.45%
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