Trisomy 21 is the most common form of Down syndrome.

三体症21是最常见的唐氏综合症形式。

The doctor explained that trisomy is a genetic disorder.

医生解释说三体症是一种遗传疾病。

The research focuses on the causes and effects of trisomy.

这项研究集中在三体症的原因和影响上。

Genetic testing can help detect trisomy early in pregnancy.

基因检测可以帮助在怀孕早期检测三体症。

Parents were concerned when they learned about the possibility of trisomy.

当父母得知三体症的可能性时，他们很担心。

A short femur is associated with trisomy 21 rather than trisomy 13 and holoprosencephaly.

股骨短与21-三体而不是13-三体或全前脑畸形有关.

If this is a patient with trisomy 21, it become more complicated.

如果这病人是21三体， 可能就复杂些。

Objective To evaluate significance of prenatal ultrasonography in diagnosis of trisomy 18.

目的探讨超声在18- 三体综合征产前诊断中的意义。

Polysomy , which includes trisomy, is the condition in which one or more chromosomes are represented more than twice in the cell.

多染色体包括三染色体都是一条或多条染色体代替了正常细胞中的两条染色体形成的。

There is a weak but fairly convincing association between chromosomal abnormalities such as trisomy 21 (Down syndrome) and echogenic foci in the heart.

在染色体异常（如21-三体）和心脏内强回声间有一定联系。