Intravenousinjectionofdl-tetrahydropalmati
题型：单项选择题
问题：
Intravenousinjectionofdl-tetrahydropalmatine,corydalisLord-corydalineaffordedanalgesicactionsinrabbits．
Thefirsttwoagentshadperactionsthanthelatter．镇痛作用最弱的物质是
A．dl-tetrahydropalmatine
B．corydalisL
C．d-corydaline
D．corydalineandcorydalisL
E．d-corydalineanddl-tetrahydropalmatine