If you need to Manage grants MSSQL table or any objects you can use following method,
ADD GRANTS
USE [DATABASEUSERGROUP]GOGRANT SELECT ON [dbo].[mytable] TO [Domain\username]Go
REMOVE GRANTS
USE [DATABASEUSERGROUP]GOREVOKE SELECT ON [dbo].[mytable] FROM [Domain\username]GO
Cheers...
and Most welcome your comments and ideas...