Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Vascular defects in E9.5 Arnt−/− placentas. H&E-stained Arnt+/+ (A,B) and Arnt−/− (C,D) sections showing the presence of a chorionic plate (short arrows in A and C) in both animals, but lack of fetal vessels (long arrows in B) in the labyrinthine layer of the Arnt−/− placenta (D). Original magnification in A,C: 80×; magnification of inset in B,D: 400×. (GC) Giant cells; (MD) maternal deciduum; (LT) labyrinthine trophoblast.
