1 title:Characterization of Several Clonal Lines of Cultured Ley dig Tumor Cells: Gonadotropin Receptors and Steroidogenic Responses + k! e! [+ ~, v# B6 ]. H! ?$ `Endocrinology 1981 108: 88-95; . n4 @8 S8 x5 a. A& ^) E http://endo.endojournals.org/content/108/1/88.full.pdf+html 4 y3 @8 F5 E( y7 b. N: b, W6 q1 ?6 j
2 title:Cell-Cell Interactions in the Testis 6 O6 ?4 P Z* V
Endocrine Reviews February 1991 12: 45-77; ' l. T$ m& ^. yhttp://edrv.endojournals.org/content/12/1/45.full.pdf+html . u$ H' A, N, W. T5 s. o: ~* Q; a! J/ O6 }
3 title:Secretion of activin by interstitial cells in the testis5 A y) w' H7 y1 I* B6 K1 F Z1 w
Science 20 January 1989& F0 {) U0 i; ^ http://www.sciencemag.org/content/243/4889/396.abstract