PMID-sentid	Pub_year	Sent_text		comp_official_name	comp_offsetprotein_name	organism	prot_offset
6641722-1	1983	We have used ammonium sulphate precipitation followed by affinity chromatography to partially purify the estrogen receptor from Xenopus laevis liver which may control the genes for vitellogenin, the precursor of the egg yolk proteins.	Ammonium Sulfate	13-30	a1-a	Xenopus laevis	181-193