Figure 1.
Structures of PAs. (A) Common structures of pas; (B) URM; (C) UNO and (D) senecionine (IS).
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.