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Spencer TE, Gray A, Johnson GA, Taylor KM, Gertler A, Gootwine E, Ott TL, Bazer FW.Spencer TE, et al. Among authors: johnson ga.Biol Reprod. 1999 Dec;61(6):1409-18. doi: 10.1095/biolreprod61.6.1409.Biol Reprod. 1999.PMID: 10569983