著者名,論文名,雑誌名,ISSN,出版者名,出版日付,巻,号,ページ,URL,URL(DOI) FANG YMV,Down syndrome screening in the United States in 2001 and 2007 : a survey of maternal-fetal medicine specialists,Am J Obstet Gynecol,,,2009,201,97,e1-e5,https://cir.nii.ac.jp/crid/1573105975603494400,