谁能告诉我 nuchal translucency “颈半透明度” 究竟是什么玩意啊?谢谢! 解释最好能浅显易懂! PS: The costs of screening tests included laboratory expenses (consumables and staff), informing the women of the results (by telephone if positive, by post if negative), service costs (including processing results and monitoring the service), overheads, and (for nuchal translucency measurement) training . The costs of chorionic villus sampling and amniocentesis included counselling before the procedure, equipment and staff to do the procedure, laboratory expenses (consumables and staff, non-reagent and labour costs), and overheads. For all these costs, we assumed an existing infrastructure for antenatal screening and diagnosis of Down's syndrome. We also estimated costs of events arising from screening . All costs were adjusted to June 1998 prices