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     Many people think that animals in the zoo are (1) h______ and lucky. But (2) m______ of them are sad.

Do you know why? Animals like tigers, (3) l______ and bears (4) u______ live in forests and (5) m______.

They can run, jump, play with their (6) c______ and catch small animals for food. But now they have to

(7) s______ in small rooms in the zoo. They don't have to (8) f______ food by themselves (9) b______ the

zoo keepers feed them. They do nothing but eat, walk and (10) s______ every day.

类白血病与白血病的鉴别中必不可少的一项是（）

A.血象

B.骨髓象

C.细胞化学染色

D.Ph染色体

E.组织活检