Submitted on: 20 February 1998.
Revised on: 02 April 1998.
Accepted on: 01 June 1998.
___________________Frontiers in Pharmacology---FRONTIERS MEDIA SA
http://reply.papertrans.cn/2/103/10216/10216-32.png
Submitted on: 24 February 1998.
Revised on: 17 April 1998.
Accepted on: 14 June 1998.
___________________Frontiers in Pharmacology---FRONTIERS MEDIA SA
http://reply.papertrans.cn/2/103/10216/10216-34.png
Submitted on: 01 January 2004.
Revised on: 19 April 2004.
Accepted on: 23 May 2004.
___________________Frontiers in Pharmacology---FRONTIERS MEDIA SA
http://reply.papertrans.cn/2/103/10216/10216-36.png