病儿,女,3d。第1胎,过期剖腹产。出生体重2500g。其母孕期无疾病及服药史,仅感胎动微弱。女出生时父母年龄均为27岁,父母非近亲婚配,家族无类似病人。查体:头围33cm,体重2300g,身长43cm。头前后径长,枕骨突出,两眼及眉距宽,左耳比右耳低,腭弓高。双肺有湿啰音种复侄獭⑶⒅氐?不易伸直,左手小指二节,无通贯掌。双膝关节过伸,肌张力低,双足下垂内翻。大阴唇发育不良,小阴唇外露。外周血淋巴细胞染色体G显带核型为47,xx,+18。追查父母核型均正常。诊断:18三体综合征。论讨18三体综合征是次于先天愚型的第二种常染色体异常疾病。1960年由 Sick child, female, 3d. The first child, expired Caesarean section. Birth weight 2500g. The first trimester of disease and medication history, only feeling fetal movement weak. Parents are 27 years of age at birth, parents are non-relatives of marriage, the family has no similar patients. Physical examination: head circumference 33cm, weight 2300g, length 43cm. Long before and after the head diameter, occipital prominent, eyes and eyebrows wide, left ear lower than the right ear, palatal arch high. The lungs have wet rales  kind of complex 侄 ⒅ ⒅ 氐 ⒅ 不? Not easy to straight, the left little finger section, without palm. Double knee joint hyperextension, low muscle tension, bipedal ptosis. Labia majora dysplasia, labia minora exposed. Peripheral blood lymphocyte chromosome G band karyotype 47, xx, +18. Tracing the karyotypes were normal parents. Diagnosis: 18 Trisomy. Discussion of Trisomy 18 is second to Down’s syndrome of the second autosomal dominant disorder. 1960 by