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We report a female infant noted prenatally to have an umbilical cord mass. At birth, a labial strawberry haemangioma was noted. She subsequently developed an abdominal mass which was discovered to be a proliferating haemangioma, continuous with both the labial and the umbilical stump lesions.  相似文献   
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A therapeutic abortion was conducted on a 17-week-old male fetus with a large umbilical cord teratoma associated with an exomphalos. A review of the literature revealed ten other cases of umbilical cord teratoma and shows that these tumors have a very polymorphic presentation. Four fetuses and infants died from various causes indicating that there is a need for close follow-up of pregnancies with umbilical cord teratoma. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
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Prenatal prediction in families at risk for autosomal recessive proximal spinal muscular atrophy (SMA) mainly of type I is often requested due to the high incidence and the fatal outcome of the disease. So far, only indirect genotype analysis can be performed in SMA families, since the gene has not yet been identified. We present our experience of 109 prenatal diagnoses obtained in 91 families by use of single- and multi-locus polymorphic microsatellites of the region 5q11.2–q13.3. The marker combinations and specific features of the closest microsatellites are described in detail. From 137 requests for prenatal prediction of SMA between October 1991 and August 1994, 28 families were excluded, mostly because the clinical diagnosis was uncertain or doubtful. Others had to be classified as ‘SMA-variants’ or showed autosomal dominant transmission of SMA. Of the 109 prenatal diagnoses performed, 29 fetuses were diagnosed to be at high risk (>99 per cent) of developing the disease, while in seven additional pregnancies no exact prediction could be made due to a recombination event in one parental haplotype. Altogether, recombinations between closely flanking markers were observed in 14 cases. In 35 cases, the parents decided to terminate the pregnancy. Of the remaining pregnancies, 32 could be followed beyond term. All infants were reported to develop normally without signs of SMA. Two children were born with transverse reduction defects of one hand, which was most likely related to early chorionic villus sampling at 9 and 10 weeks' gestation. No further abnormalities could be detected. The limits of indirect genotype analysis and the problems of diagnostic accuracy and heterogeneity of proximal SMA are discussed.  相似文献   
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Objective: The aim of this study was to investigate the whole spine alignment in automotive seated postures for both genders and the effects of the spinal alignment patterns on cervical vertebral motion in rear impact using a human finite element (FE) model.

Methods: Image data for 8 female and 7 male subjects in a seated posture acquired by an upright open magnetic resonance imaging (MRI) system were utilized. Spinal alignment was determined from the centers of the vertebrae and average spinal alignment patterns for both genders were estimated by multidimensional scaling (MDS). An occupant FE model of female average size (162 cm, 62 kg; the AF 50 size model) was developed by scaling THUMS AF 05. The average spinal alignment pattern for females was implemented in the model, and model validation was made with respect to female volunteer sled test data from rear end impacts. Thereafter, the average spinal alignment pattern for males and representative spinal alignments for all subjects were implemented in the validated female model, and additional FE simulations of the sled test were conducted to investigate effects of spinal alignment patterns on cervical vertebral motion.

Results: The estimated average spinal alignment pattern was slight kyphotic, or almost straight cervical and less-kyphotic thoracic spine for the females and lordotic cervical and more pronounced kyphotic thoracic spine for the males. The AF 50 size model with the female average spinal alignment exhibited spine straightening from upper thoracic vertebra level and showed larger intervertebral angular displacements in the cervical spine than the one with the male average spinal alignment.

Conclusions: The cervical spine alignment is continuous with the thoracic spine, and a trend of the relationship between cervical spine and thoracic spinal alignment was shown in this study. Simulation results suggested that variations in thoracic spinal alignment had a potential impact on cervical spine motion as well as cervical spinal alignment in rear end impact condition.  相似文献   

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We report a case of monochorionic diamniotic twin gestation confirmed by ultrasound visualization of the thin intertwin-dividing membrane at 32 weeks' gestation. Ultrasound at 36 weeks failed to demonstrate the thin dividing membrane. The pregnancy ended a few days later with spontaneous vaginal delivery of the first twin. The second twin was in transverse lie with no membranes that could be felt around. Severe fetal heart rate deceleration developed, prompting delivery by emergency caesarean section. Cord entanglement was noted at the time of delivery, which resulted in severe perinatal morbidity of the second twin. The antepartum rupture of the dividing membrane must have happened some time between 32 and 36 weeks. The etiology for this intrauterine disruption is unknown. A review of the literature about the antepartum rupture of the intertwin-dividing membrane is described, along with its possible causes and complications. In addition, we discuss possible causes of incorrect amnionicity determination, and thus how to minimize these pitfalls. We conclude that antepartum disruption of the intertwin-dividing membrane is more common than previously thought. Moreover, prenatal ultrasonographic visualization of a dividing membrane in a diamniotic twin pregnancy does not rule out future change in this environment to a monoamniotic one, with all its perinatal morbidity and mortality complications, which result mainly from cord entanglement. This suggests a modification in the method and frequency of the prenatal fetal well-being follow-up, as well as the time and mode of delivery. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
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