{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2022,4,4]],"date-time":"2022-04-04T06:58:10Z","timestamp":1649055490091},"reference-count":0,"publisher":"Akademiai Kiado Zrt.","issue":"28","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Orvosi Hetilap"],"published-print":{"date-parts":[[2018,7]]},"abstract":"<jats:p> Abstract: <\/jats:p><jats:p> Down syndrome is the most common autosomal chromosomal abnormality. According to the classical interpretation, it is the result of meiotic nondisjunction. Its occurrence is more common in advanced maternal age. Despite intensive research, pathophysiology of this genetic disorder is not fully understood. According to recent studies, a different kind of mechanism may be found in the background of trisomy 21 than was previously considered. Based on the ovarian mosaicism model, the cause of trisomy 21 (or any common trisomy) is a segregation error of a chromosome in premeiotic mitosis. The cell entering meiosis will be an oocyte with preexisting trisomy, where its (so-called \u201csecondary\u201d) nondisjunction is essential. Maturation of the trisomic oocytes appears to fall behind the disomic oocytes, resulting in their relative accumulation in the ovaries as time progresses. The ratio of trisomic\/disomic cells becomes less favorable in maternal maturity. If ovulation is inhibited \u2013 although the number of oocytes will continue to decline due to apoptosis \u2013 it can be assumed that the trisomic\/disomic oocyte ratio remains more favorable with the progression of age. In our summary report, presenting and updating our previous data, we would like to propose that \u2013 according to ovarian mosaicism model \u2013 long-term oral contraception in the anamnesis may be beneficial in pregnancies with advanced maternal age. Orv Hetil. 2018; 159(28): 1146\u20131152. <\/jats:p>","DOI":"10.1556\/650.2018.31094","type":"journal-article","created":{"date-parts":[[2018,7,8]],"date-time":"2018-07-08T08:49:56Z","timestamp":1531039796000},"page":"1146-1152","source":"Crossref","is-referenced-by-count":0,"title":["A terhess\u00e9get megel\u0151z\u0151en alkalmazott hosszabb t\u00e1v\u00fa                     or\u00e1lis fogamz\u00e1sg\u00e1tl\u00e1s mint a magzati 21-es trisz\u00f3mia lehets\u00e9ges                     kock\u00e1zatcs\u00f6kkent\u0151 t\u00e9nyez\u0151je id\u0151s anyai \u00e9letkorban v\u00e1llalt                     terhess\u00e9gben"],"prefix":"10.1556","volume":"159","author":[{"given":"D\u00e1niel","family":"Hor\u00e1nyi","sequence":"first","affiliation":[{"name":"Sz\u00fcl\u00e9szeti \u00e9s N\u0151gy\u00f3gy\u00e1szati Oszt\u00e1ly,                         P\u00e9terfy S\u00e1ndor Utcai K\u00f3rh\u00e1z-Rendel\u0151int\u00e9zet \u00e9s Baleseti K\u00f6zpont Budapest, P\u00e9terfy S. u. 8\u201320., 1076"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lilla \u00c9va","family":"Babay","sequence":"additional","affiliation":[{"name":"Sz\u00fcl\u00e9szeti \u00e9s N\u0151gy\u00f3gy\u00e1szati Oszt\u00e1ly, Uzsoki Utcai K\u00f3rh\u00e1z Budapest"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bal\u00e1zs","family":"Gy\u0151rffy","sequence":"additional","affiliation":[{"name":"II. Gyermekgy\u00f3gy\u00e1szati Klinika, Semmelweis Egyetem, \u00c1ltal\u00e1nos Orvostudom\u00e1nyi Kar Budapest"},{"name":"Enzimol\u00f3giai Int\u00e9zet, MTA Term\u00e9szettudom\u00e1nyi Kar Budapest"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gyula Rich\u00e1rd","family":"Nagy","sequence":"additional","affiliation":[{"name":"I. Sz\u00fcl\u00e9szeti \u00e9s N\u0151gy\u00f3gy\u00e1szati Klinika,                         Semmelweis Egyetem, \u00c1ltal\u00e1nos Orvostudom\u00e1nyi Kar Budapest"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"425","container-title":["Orvosi Hetilap"],"original-title":[],"language":"hu","link":[{"URL":"https:\/\/www.akademiai.com\/doi\/pdf\/10.1556\/650.2018.31094","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2019,2,19]],"date-time":"2019-02-19T17:48:28Z","timestamp":1550598508000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.akademiai.com\/doi\/10.1556\/650.2018.31094"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2018,7]]},"references-count":0,"journal-issue":{"issue":"28","published-print":{"date-parts":[[2018,7]]}},"alternative-id":["10.1556\/650.2018.31094"],"URL":"https:\/\/doi.org\/10.1556\/650.2018.31094","relation":{},"ISSN":["0030-6002","1788-6120"],"issn-type":[{"value":"0030-6002","type":"print"},{"value":"1788-6120","type":"electronic"}],"subject":[],"published":{"date-parts":[[2018,7]]}}}