在15周到18周之间有两个极好的检查可以选择来甄别染色体异常和神经管缺损症状，比如：唐氏综合症和脊柱裂。

There are two test options available between the 15th and 18th weeks to screen for chromosomal abnormalities and neural tube defects such as Down's syndrome and spina bifida.

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日本的天文学家说，最知名星云之一的人马座三裂星云，它的壮丽景观可正是由两朵气体和尘埃云的碰撞造成的。

Astronomers in Japan say one of the best-known nebulae-the Trifid, in the constellation sagittarius-owes its splendor to a smashup between two clouds of gas and dust.

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我的鼻梁骨断了，颅骨骨折，颈部有两根骨头被高温熔化而接在一起，四根肋骨骨裂，脊椎上也有一处骨折，左肩关节脱臼，这处伤至今未曾痊愈。

I had a broken nose, a skull fracture, two fused bones in my neck, four cracked ribs, a fracture in my spine and my left shoulder is still separated.

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