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91.
First-trimester maternal serum alpha-fetoprotein (AFP) and human chorionic gonadotropin (HCG) levels were measured in samples from 29 women with cytogenetically abnormal pregnancies and 145 women with cytogenetically normal pregnancies matched for gestational age, race, and sample storage time. All patients had a risk of fetal aneuploidy greater than or equal to that of a mother 35 years of age. AFP was significantly lower in samples from pregnancies affected with trisomy 21 (0.67 MoM;p <0.05), while HCG values were no different from those of matched controls. Trisomies 13 and 18 could not be distinguished from matched controls by AFP. However, levels of HCG were significantly lower in such pregnancy samples, with median values of 0.65 MoM in trisomy 13 and 0.32 MoM in trisomy 18 (p<0.05). Variations in AFP and HCG levels suggest that expressed differences between autosomal aneuploidies include differences in fetal and placenta! protein production in the first trimester.  相似文献   
92.
职业性肌肉骨骼疾患是园林工人的常见职业病,严重影响园林工人的工作效率和身体健康。对18名从事园林割灌作业的工人通过NMQ北欧肌肉骨骼系统问卷调查表进行调查,统计得出园林割灌作业的下背痛患病率约在60%左右,从事割灌整枝作业工人下背痛患病率为25%,从事割草作业下背痛患病率达444%,割草作业的下背痛患病率明显高于割灌整枝操作者。应用SPSS190软件进行下背痛的危害因子分析,得出下背痛的发生主要与重复动作、工龄、日提举负荷等有关。  相似文献   
93.
Fluoride (F) is mainly ingested through drinking water and food. In addition to producing dental and skeletal fluorosis, excess fluoride may affect the functioning of many organs including the thyroid gland. The present study investigated the thyroid function of subjects with dental fluorosis from F-endemic areas of Gaya region, Bihar, India and compared it with control individuals from Bodh Gaya. The mean F concentration in groundwater of F-endemic area was 2.82 ± 0.18 mg/L (range 0.62–7.2 mg/L), while that of control area was 0.49 ± 0.04 mg/L (range 0.21–0.76 mg/L). Abnormal levels of T3, T4, and TSH were found in the study subjects from both control and F-endemic areas.  相似文献   
94.
The present report describes two fetuses, one female and one male, with thus far undescribed skeletal malformations. The mother was a gravida 2, para 0. Both pregnancies were terminated in the second trimester because of multiple congenital anomalies diagnosed ultrasonographically resembling a short rib-polydactyly syndrome. Both fetuses were found to have postaxial hexadactyly of the hands and feet, marked bilateral campomelia of the forearm and shank bones, and a Dandy–Walker cyst. In addition, the fourth ventricle was dilated in the first sibling and the second sibling had an inverse intestinal malrotation. A literature search failed to reveal similar observations. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
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