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Haemolytic disease of the fetus and newborn (HDFN) due to red cell alloimmunization was a significant cause of fetal and neonatal morbidity and mortality until the introduction of anti-D immunoglobulin, which has dramatically changed the incidence of the disease. However, it is still a major problem in affected pregnancies. The emphasis of current clinical management has shifted from an invasive approach to non-invasive monitoring of the disease. The key elements of the modern management are determining which fetuses are at risk of HDFN with the use of cell-free fetal DNA in maternal plasma (fetal RHD genotype) and the follow-up of antigen positive fetuses by Doppler ultrasonography to detect anaemia severe enough to need treatment. When anaemia is suspected, an invasive approach is still required in a timely manner for confirmation of the degree of anaemia and to administer blood transfusions. This non-invasive approach prevents unnecessary administration of human-derived blood products, with the consequent ethical and cost implications and most importantly avoids iatrogenic conversion of mild to severe disease by avoiding need for techniques such as amniocentesis. The potential problem of the non-invasive approach is the reduction in the total number of invasive procedures, with the subsequent difficulty of maintaining the skills required to perform them. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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In this short review, the objectives and work of SAFE—the Special Non-invasive Advances in Fetal and Neonatal Evaluation Network, a European Union Framework VI network of excellence is described. We demonstrate how this network facilitates the implementation of non-invasive prenatal diagnosis (NIPD) for single gene disorders, fetal rhesus typing, aneuploidy and pregnancy complications. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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Illicit trafficking of fissionable material in container cargoes is recognized as a potential weakness in Nuclear Security. Triggered by the attacks of 11 September 2001, measures were undertaken to enhance maritime security in extension to the Safety Of Life At Sea Convention and in line with the US Container Security Initiatives. Effective detection techniques are needed that allow the inspector to intercept illicit trafficking of nuclear weapons components or components of other nuclear explosive devices. Many security measures focus on active interrogation of the container content by X-ray scan, which might be extended with the newly developed tagged neutron inspection system. Both active interrogation techniques can, with the current huge volume of container traffic, only be applied to a limited number of selected containers. The question arises whether a passive detection technique can offer an alternative solution. This study investigates if containers equipped with a small passive detector will register during transport the neutron irradiation by fissionable material such as plutonium in a measurable way. In practice, 4/5 of the containers are about 1/8 filled with hydrogenous material and undergo a typical 2 months route. For this reference case, it was found that the most compatible passive detector would be an activation foil of iridium. Monte-Carlo simulations showed that for the reference case the activity of a 250 μm thin foil with 6 cm2 cross-section would register 1.2 Bq when it is irradiated by a significant quantity of Reactor-Grade PuO2. However this activity drops with almost two orders of magnitude for other fillings and other isotopic compositions and forms of the Pu-source. The procedure of selecting the target material for Pu detection is detailed with the theoretical methods, in order to be useful for other applications. Moreover the value of such additional passive sensors for securing maritime container transport is situated within the global framework of the First, Second and Third Line of Defense against illicit trafficking. 相似文献