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81.
Epignathi are unusual congenital tumours presenting as oropharyngeal masses, often resulting in rapid asphyxia following birth. Occasionally, intracranial extension of the tumour is present, and two such cases are described. The presence of this complication, diagnosable by ultrasound examination, indicates that aggressive surgical treatment is inappropriate.  相似文献   
82.
We report two cases of prenatal detection of lissencephaly by high-resolution ultrasound. The first case studied was referred for high-risk obstetrical management and serial antenatal ultrasounds because of a family history of lissencephaly in an unresolved chromosomal abnormality. Diagnosis of a smooth gyral pattern consistent with lissencephaly was made at 32 weeks' gestation. The second case was referred for prenatal ultrasound because of a size versus dates discrepancy. The ultrasound examination showed a smooth gyral pattern at 31.5 weeks. In light of this ultrasound finding, a fetal blood sample was obtained and a chromosomal abnormality reported, confirming the diagnosis. To our knowledge, these cases represent the first report of the sonographic prenatal diagnosis of cerebral agyria or lissencephaly.  相似文献   
83.
We have studied the opinions and attitudes of women towards prenatal diagnosis (amnio-centesis/chorionic villus sampling/ultrasound/serum AFP testing). A questionnaire was sent to 185 women who had had their first baby a few months before. The respondents have a strong positive attitude towards the diagnostic procedures, especially if treatable abnormalities can be detected. Younger women and women with a high level of education were less inclined to make use of prenatal diagnosis. If tests were made more widely available, this might lead to a significant increase in the use of prenatal diagnosis.  相似文献   
84.
Aplasia cutis congenita associated with epidermolysis bullosa and pyloric atresia is a rare congenital disease in which localized or widespread areas of skin are absent at birth. Alpha- fetoprotein (AFP) and skin biopsy have been used for prenatal diagnosis of this condition. A patient in whom normal levels of amniotic AFP at 16 weeks' gestation presumably excluded the disease and who was at risk for aplasia cutis congenita associated with epidermolysis bullosa and pyloric atresia is described. However, 10 weeks later, ultrasonographic examination revealed hydramnios, a dilated stomach, a deformed external ear, and a contracted fisted hand. All signs were confirmed postnatally. The role of ultrasonography and the value of other diagnostic methods in this congenital disease are discussed.  相似文献   
85.
A 12-month prospective population study of antenatal patients was undertaken in a large district general hospital to assess ultrasound scanning in late pregnancy for the detection of non-lethal fetal renal abnormalities. The rate of false-negative antenatal scans during the study period was also assessed. Both 18–20 and 28–32 weeks' gestational scans were performed on 6497 pregnant women. Forty fetuses with a suspected abnormality were referred for postnatal examination and 29 neonates were found to have renal abnormalities. Of these, 21 were significant and eight were likely to be extrarenal pelves. In six, there was evidence of an abnormality at the early scan. Nine children, seven with reflux, presented within the study period, all with preceding normal antenatal scans. The incidence (0·46 per cent) of structural renal abnormalities is similar to that reported previously. A late scan is necessary for the antenatal detection of non-lethal renal abnormalities.  相似文献   
86.
Intracerebral tumours of the fetus are very rare conditions, most often presenting clinically as polyhydramnios and hydrocephalus. These conditions can be diagnosed with ultrasound and clearly differentiated from hydrocephalus and other intracranial lesions. The following report is of a case of an intracerebral tumour (glioblastoma multiforme) diagnosed at 33 weeks in utero using ultrasound. The prognosis for this condition is universally poor.  相似文献   
87.
A case of low atresia of the ileum, diagnosed prenatally by real-time ultrasound scanning, is presented. The ultrasound examination showed progressive distension of intestinal loops, with strong peristaltic movements. The stomach was also distended, presenting as a large cystic area in the upper left abdomen. Real-time ultrasound technique is most advantageous in the diagnosis of fetal ileus. Prenatal diagnosis of fetal intestinal obstruction is of great importance, making early and safe treatment of the newborn possible.  相似文献   
88.
In 3 fetuses affected by congenital chloride diarrhoea there were characteristic prenatal ultrasonic findings. In all cases the fetal abdominal cavity was filled with distended loops of fetal intestine, the fetal stomach was of normal size and polyhydramnios was present. The prenatal ultrasonic findings in this metabolic inherited disease are identical to those caused by mechanical obstruction of the distal fetal intestine. Whenever these findings are encountered prenatally, the possibility of chloride diarrhoea should be considered, because therapy with electrolytes is needed rather than the surgical intervention required in mechanical intestinal obstruction.  相似文献   
89.
The prenatal diagnosis of a presacral (type IV) sacrococcygeal teratoma (SCT) is described. The initial ultrasound appearance was suggestive of a lower urinary tract obstruction, but further ultrasonic examination and radiological imaging using contrast medium led to the diagnosis of SCT. This is the first prenatal diagnosis of a totally intra-abdominal SCT.  相似文献   
90.
超声辐照对水中化学污染物的降解   总被引:12,自引:0,他引:12  
超声辐照处理水中化学污染物取得了良好的效果,受到人们的关注。论述了超声辐照降解化学污染物的反应机理、降解速度、影响因素及超声辐照对微生物的影响;同时也指出了超声技术的发展方向和实际应用中面临的问题。  相似文献   
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