PubMed Health⌕ Search

Biomedical subjects

S Y Ying

Publications and source records attributed to S Y Ying.

3 recordsLinked to original sources
PubMed1979

[Gonadostatin and gonadocrinin, polypeptides of ovarian origin with hypophysiotropic activity].

Crude acetic acid extract of Rat ovaries pretreated with pregnant mare serum (PMSG) contains native peptides with two types of separable biological activities: one, molecular weight greater than 10,000 dalton inhibits the secretion of both LH and FSH as stimulated by luteinizing hormone releasing factor (LRF) in a pituitary monolayer culture system and is referred to as gonadostatin; the other, less than 3,500 dalton, stimulates the secretion of gonadotropins and is designated as gonadocrinin. The biological activities of ovarian gonadocrinin can be competitively inhibited by an LRF-analog-antagonist, D-Phe2, D-Trp6-LRF. These ovarian peptides may participate in physiological control of pituitary LH/FSH secretion.

Animals↗
PubMed1979

Dried Staphylococcus aureus as a rapid immunological separating agent in radioimmunoassays.

A rapid (less than or equal to 60 seconds) immunological separation of antigen-antibody complexes from free antigen has been developed in radioimmunoassays (RIAs) of luteinizing hormone (LH), follicle stimulating hormone (FSH), prolactin (PRL) and beta-endorphin by using suspensions of dried Staphylococcus aureus rich in protein-A. In the systems tested parallel dose-response curves were obtained for protein-A and second antibody precipitations. The sensitivity of the protein-A method is equal to or higher than that of second antibody method. Tissue culture medium and serum hormone levels measured with RIAs using protein-A are similar to those detected with double antibody methods. The technique may be of general use in all RIAs utilizing antisera from species whose IgG are known to be bound by protein-A.

Antigen-Antibody Complex↗