plpgsql - accessing field in RECORD variable by text variables

Hello!

I have the following code which does not work:

CREATE OR REPLACE FUNCTION td1(integer) RETURNS REFCURSOR AS '
DECLARE
r article%ROWTYPE;
BEGIN

SELECT INTO r * FROM article WHERE key = $1;
a := ''some_other_field'';
RAISE NOTICE ''%'', r.a;
END;
' LANGUAGE 'plpgsql';

SELECT td1(229);

I would like to access RECORD type variables fields by assigning field (attribute) name
to some text variable and then access the field in RECORD which has the same name.

Is this possible in plpgsql?

I can not use the dot notation (fully qualification). What I would like to do
is some automatic field copying from another table to table being updated
and that this field copying can be managed in DB by changing some record in
my meta table.

Damjan