{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,10]],"date-time":"2026-06-10T15:39:57Z","timestamp":1781105997206,"version":"3.54.1"},"reference-count":0,"publisher":"National Academy of Sciences","issue":"4","content-domain":{"domain":["www.pnas.org"],"crossmark-restriction":true},"short-container-title":["Proc. Natl. Acad. Sci. U.S.A."],"published-print":{"date-parts":[[1974,4]]},"abstract":"<jats:p>\n                    In a very active cell-free system containing polysomes derived from human placenta and a cell-sap fraction prepared from ascites tumor cells, the synthesis of the hormone human placental lactogen (HPL) was detected. The identification was based on the following: (\n                    <jats:italic>a<\/jats:italic>\n                    ) The\n                    <jats:italic>in vitro<\/jats:italic>\n                    synthesized protein labeled with [\n                    <jats:sup>35<\/jats:sup>\n                    S]methionine migrated at the same rate as authentic HPL on sodium dodecyl sulfate-polyacrylamide gels and (\n                    <jats:italic>b<\/jats:italic>\n                    ) tryptic fingerprint analysis of the labeled protein yielded peptides having the same mobilities as seen with the same analysis of purified HPL.\n                  <\/jats:p>\n                  <jats:p>The amount of HPL synthesized in a cell-free system containing polysomes derived from term placenta was about 10% of the total proteins synthesized and in a comparable system containing first trimester ribosomes the level of synthesis was about 5%. These data suggest the potential for quantitating the HPL mRNA activity as a function of the period of gestation and for isolating the mRNA itself.<\/jats:p>","DOI":"10.1073\/pnas.71.4.1322","type":"journal-article","created":{"date-parts":[[2006,5,31]],"date-time":"2006-05-31T02:53:50Z","timestamp":1149044030000},"page":"1322-1325","update-policy":"https:\/\/doi.org\/10.1073\/pnas.cm10313","source":"Crossref","is-referenced-by-count":31,"title":["The Synthesis of Human Placental Lactogen by Ribosomes Derived from Human Placenta"],"prefix":"10.1073","volume":"71","author":[{"given":"Irving","family":"Boime","sequence":"first","affiliation":[{"name":"Department of Obstetrics, Washington University School of Medicine, 660 S. Euclid Ave., St. Louis, Missouri 63110"},{"name":"Department of Gynecology and Pharmacology, Washington University School of Medicine, 660 S. Euclid Ave., St. Louis, Missouri 63110"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sophie","family":"Boguslawski","sequence":"additional","affiliation":[{"name":"Department of Obstetrics, Washington University School of Medicine, 660 S. Euclid Ave., St. Louis, Missouri 63110"},{"name":"Department of Gynecology and Pharmacology, Washington University School of Medicine, 660 S. Euclid Ave., St. Louis, Missouri 63110"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"341","published-online":{"date-parts":[[1974,4]]},"container-title":["Proceedings of the National Academy of Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/pnas.org\/doi\/pdf\/10.1073\/pnas.71.4.1322","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,4,13]],"date-time":"2022-04-13T10:43:43Z","timestamp":1649846623000},"score":1,"resource":{"primary":{"URL":"https:\/\/pnas.org\/doi\/full\/10.1073\/pnas.71.4.1322"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1974,4]]},"references-count":0,"journal-issue":{"issue":"4","published-print":{"date-parts":[[1974,4]]}},"alternative-id":["10.1073\/pnas.71.4.1322"],"URL":"https:\/\/doi.org\/10.1073\/pnas.71.4.1322","relation":{},"ISSN":["0027-8424","1091-6490"],"issn-type":[{"value":"0027-8424","type":"print"},{"value":"1091-6490","type":"electronic"}],"subject":[],"published":{"date-parts":[[1974,4]]},"assertion":[{"value":"1974-04-01","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}