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161.
Cytomegalovirus is the main cause of congenital viral infection and amniotic fluid viral load appears to be the single nonclinical prognostic factor. However, as in other infectious diseases, host genetics may influence the severity of the disease. To test this hypothesis, we looked retrospectively at the fetal gender in cases of severe congenital cytomegalovirus infection in our database. We also analyzed the international English literature covering this subject between 1985 and 2003. The proportion of females with brain abnormalities was statistically different from that of males (62/258: 24% vs 30/251: 12%, p = 0.004). The risk of abnormal brain development in infected fetuses was twice as high in females than in males (Chi2 = 8.7; OR = 2, IC [1.26–3.21]). In our cases, amniotic fluid CMV DNA load was not significantly higher in males than in females (p = 0.06) and was also similar in severely and non-severely infected fetuses (p = 0.09). Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
162.
Dehydrated hereditary stomatocytosis (DHS) is a rare congenital hemolytic anemia. We observed that some patients had presented with different prenatal or perinatal forms of edema in some kindreds. Within weeks or months after birth, these exhibited a spontaneous, complete and definitive resorption. We assumed that some DHS patients, who were born without edema before ultrasound was available, might nonetheless have exhibited this during the prenatal period. The present report follows up the first pregnancy in a woman with overt DHS, but not herself having a known history of perinatal effusions. Ultrasound revealed that the fetus displayed ascites that disappeared prior to birth. The neonate had DHS. Prenatal edema must therefore be more frequent in DHS than known until now. DHS is another cause of prenatal edema to be considered in the differential diagnosis. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
163.
To illustrate the three-dimensional sonographic features of a rare genetic disorder, we report on prenatal diagnosis of osteogenesis imperfecta congenita associated with encephalocele at 13 weeks of gestation, using conventional and three-dimensional ultrasound. Because the parents were first-degree cousins and on the basis of the family history, a recessive autosomal inheritance was suspected. Of seven previous pregnancies, five were unaffected and two had been terminated in the second trimester owing to a similar abnormality (one affected boy and one affected girl). In the case we present, the diagnosis was made on the basis of two-dimensional ultrasound performed by physicians aware of the history; the quality of three-dimensional ultrasound imaging suggests that this technique might have contributed toward establishing a precise diagnosis in the absence of a positive family history. Besides, the global view provided by three-dimensional surface-rendering images made the parents more confident of the accuracy of the diagnosis. Although osteogenesis imperfecta congenita is generally considered as autosomal dominant, the case we report suggests that it may be inherited in a recessive autosomal fashion at least when associated with encephalocele. Three-dimensional ultrasound confirmed the conventional two-dimensional examination and was helpful in convincing the parents of the accuracy of the diagnosis. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
164.
This paper concerns the difficulty of taking long-term effects on health into account in an economic valuation. Indeed, public decision makers should incorporate the cessation lag between implementation of an abatement policy and achievement of all of the expected mortality-related benefits for any projects involving health impacts. This paper shows how this time lag problem can be handled by proposing two approaches—either in terms of deaths avoided or of life years saved—within a dynamic perspective. The main findings are that long-term health benefits calculated by standard methods and widely applied to adverse health effects should be corrected downwards when incorporated into an economic analysis. The magnitude of correction depends on the discount rate, on technical choices dealing with epidemiology and on the method chosen to assess mortality benefits.  相似文献   
165.
When assessing human health or ecosystem impacts of chemicals several calculation steps need to be addressed. Matrix algebra solving techniques are a useful approach to structure and solve the system of mass balance equations assessing chemical fate in environmental multimedia models. We suggest expanding this matrix approach towards a framework which includes the exposure, effect, and damage assessment for human health and ecosystems, also applicable to spatial modeling. Special emphasis is laid upon interpretation of the physical meaning of different elements within the matrices. The proposed framework provides several advantages such as simplified updating or extending of models to new impact pathways, possibility of covering various models within the same framework and transparency. Interpretation of intermediate and final results is facilitated, e.g., allowing for direct identification of dominating exposure pathways. Model comparability and evaluation is well supported, as the four matrices contain all intermediate results in a clear and interpretable way, independent from parameters, such as amount and place of emission. Multidisciplinary work is strongly facilitated enabling the linkage of different models from various disciplines together, since each of its modules defines a clear interface of intermediate results. This framework was reviewed by an independent expert panel within a UNEP/SETAC workshop, and adopted as starting-point for new advances in modeling environmental toxic releases within the UNEP/SETAC Life Cycle Initiative.  相似文献   
166.
Here we show that trying to rob prey (cleptobiosis) from a highly specialized predatory ant species is risky. To capture prey, Allomerus decemarticulatus workers build gallery-shaped traps on the stems of their associated myrmecophyte, Hirtella physophora. We wondered whether the frequent presence of immobilized prey on the trap attracted flying cleptoparasites. Nine social wasp species nest in the H. physophora foliage; of the six species studied, only Angiopolybia pallens rob prey from Allomerus colonies. For those H. physophora not sheltering wasps, we noted cleptobiosis by stingless bees (Trigona), social wasps (A. pallens and five Agelaia species), assassin bugs (Reduviidae), and flies. A relationship between the size of the robbers and their rate of capture by ambushing Allomerus workers was established for social wasps; small wasps were easily captured, while the largest never were. Reduviids, which are slow to extract their rostrum from prey, were always captured, while Trigona and flies often escaped. The balance sheet for the ants was positive vis-à-vis the reduviids and four out of the six social wasp species. For the latter, wasps began by cutting up parts of the prey’s abdomen and were captured (or abandoned the prey) before the entire abdomen was retrieved so that the total weight of the captured wasps exceeded that of the prey abdomens. For A. pallens, we show that the number of individuals captured during attempts at cleptobiosis increases with the size of the Allomerus’ prey.  相似文献   
167.
168.
Congenital splenic cyst (CSC) is a rare condition, and only a few cases with prenatal diagnosis and no associated malformation have been reported. Spontaneous regression is possible in case of mild CSC (under 40 mm), but enlargement or secondary complications may lead to surgical treatment. We report, herein, two cases of isolated mild CSC with complete spontaneous postnatal regression. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
169.
170.
For the past decades, growing attention has been given to aspirin use during pregnancy. It favors placentation by its proangiogenic, antithrombotic, and anti-inflammatory effects. Therefore, low doses of aspirin are prescribed in the prevention of placenta-mediated complications, mainly preeclampsia and fetal growth restriction. However, questions regarding its clinical application are still debated. Aspirin is effective in preventing preeclampsia in a high-risk population. Most guidelines recommend that risk stratification should rely on medical history. Nevertheless, screening performances dramatically improve if biochemical and biophysical markers are included. Concerning the appropriate timing and dose, latest studies suggest aspirin should be started before 16 weeks of pregnancy and at a daily dose of 100 mg or more. Further studies are needed to improve the identification of patients likely to benefit from prophylactic aspirin. Besides, the role of aspirin in the prevention of fetal growth restriction is still questioned.  相似文献   
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