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741.
742.
Congenital hypophosphatasia is an autosomal recessive disorder, which usually has a fatal outcome during the neonatal period. This report presents the prenatal diagnosis of hypophosphatasia at 16 weeks of gestation. The characteristic ultrasonic findings in this abnormality demonstrate the superiority of ultrasound as compared with radiography.  相似文献   
743.
The prenatal detection of hypoxanthine phosphoribosyltransferase (HPRT, EC 2.4.2.8) deficiency, the Lesch-Nyhan syndrome, during the first trimester of an affected pregnancy through the use of chorionic villus sampling is reported. Quantitation of reaction products formed by villus cell extracts from exogenous hypoxanthine-8-[14C] or adenine-8-[14C] is used in diagnosis. We report the diagnosis of Lesch-Nyhan syndrome using a chorionic villus specimen and confirmation of that diagnosis. In addition, adenosine deaminase (ADA) and purine nucleoside phosphorylase (PNP), enzymes deficient in inherited immune disorders, are detected in chorionic villus samples. These heritable disorders also appear amenable to early prenatal diagnosis.  相似文献   
744.
Six cases of cystic hygromas detected during second trimester ultrasound examination are reported: 4 fetuses (67 per cent) had a 45, X karyotype, 1 fetus had trisomy 18, 1 fetus had a normal karyotype (46,XX) and at autopsy multiple anomalies were observed. In the latter case the family history suggested an autosomal recessive pattern of inheritance. In order to reach a definite diagnosis and give proper genetic counselling when a fetus is found to have cystic hygroma, a fetal karyotype as well as a family and reproductive history should be obtained.  相似文献   
745.
In order to accurately detect the fetal behavioural state, we simultaneously measured fetal heart rate and multiple fetal activities in 27 healthy pregnant women at 38 to 40 weeks of gestation. We ultrasonically identified gross body movements, breathing movements and micturition. Analysis of fetal heart rate allowed us to distinguish two different patterns of fetal behaviour: active and quiet phases. The frequency distribution of the analysed fetal events was significantly different in these two phases. These data suggest that a complete biophysical profile of the fetus is effective in differentiating behavioural states and may improve the predictive accuracy of fetal heart rate analysis alone.  相似文献   
746.
Prenatal diagnosis of the cerebro-hepato-renal (Zellweger) syndrome has been performed in 10 pregnancies at risk by measuring both the activity of acyl CoA: dihydroxyacetonephosphate acyltransferase (DHAP-AT) and the de novo plasmalogen biosynthesis, either in cultured amniotic fluid cells or in fibroblasts cultured from a chorionic villus biopsy. In 7 of the pregnancies both tests indicated no abnormality. All 7 continued to term and normal infants were delivered. However, in amniotic fluid cells from 2 fetuses affected by Zellweger syndrome unequivocal differences from control values were found. The activity of DHAP-AT was clearly deficient and the de novo plasmalogen biosynthesis was impaired. In one pregnancy at risk prenatal diagnosis was performed during the first trimester by measuring both the DHAP-AT activity and the de novo plasmalogen biosynthesis in fibroblasts cultured from a chorionic villi biopsy. From the deficient DHAP-AT activity and the impaired de novo plasmalogen biosynthesis it was concluded that the fetus was affected. This was confirmed biochemically after induced abortion. It can be concluded that measurement of the DHAP-AT activity and the de novo plasmalogen biosynthesis provides convenient methods for the early prenatal detection of Zellweger syndrome.  相似文献   
747.
Providing parental care is potentially costly. Costs can arise through elevated energy expenditure or from an increased risk of mortality. A cost of parental care can also occur because a parent is compromised in their ability to forage. We used pumpkinseed Lepomis gibbosus, a fish with an alternative male mating strategy, to test whether parental males differed in their feeding in comparison with females and cuckolder males. To address this question, we examined the stomach contents of female, cuckolder male, and parental male pumpkinseed during the breeding season over an entire diel cycle. We showed that parental males had a lower total weight of food in their stomachs in comparison with females, while cuckolder males did not. Parental males also had a lower weight and number of chironomids in their stomachs. The temporal pattern of feeding of parental males diverged from that of females, and they had a lower probability of pupal chironomids in their stomachs, which implies spatial segregation in foraging. Parental males had a greater probability of conspecific eggs in their stomachs than females, while the probability of egg cannibalism did not differ between cuckolder males and females. Overall, these finding meet predictions in accordance with an assumption that parental care and territoriality can compromise feeding.  相似文献   
748.
749.
750.
(E)-6,10-dimethyl-5,9-undecadien-2-ol (geranyl acetol), termed here fuscol, was identified as a male-produced pheromone emitted by Tetropium fuscum (F.) and Tetropium cinnamopterum Kirby. In field experiments, traps baited with synthetic fuscol alone were not significantly attractive, but the combination of fuscol plus host volatiles (a synthetic blend of monoterpenes plus ethanol) attracted significantly more male and female T. fuscum and female T. cinnamopterum than did host volatiles alone. This is the first homoterpenoid alcohol to be described in the Cerambycidae, and the first pheromone reported from the sub-family Spondylidinae.  相似文献   
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