Use SQL Variable in Database name

I am trying to run the same query on a series of databases, but T-SQL would not let me use the variable name as the name of the database to query. Consider the following query:

DECLARE db_cursor CURSOR
FOR SELECT name FROM sys.databases WHERE LEFT(name,4) = 'SBO_' AND RIGHT(name,4) <> 'TEST'

-- declare the variables that will hold values retrieved by the cursor
DECLARE @db_id CHAR(10)
OPEN db_cursor

FETCH NEXT FROM db_cursor INTO @db_id

-- loop through the results
WHILE @@FETCH_STATUS = 0
BEGIN
      SELECT CompnyName FROM [@db_id]..[OADM]
      --SELECT @db_id (this works fine, the above does not)
      FETCH NEXT FROM db_cursor INTO @db_id
      
END

-- close and deallocate the cursor
CLOSE db_cursor
DEALLOCATE db_cursor

Anybody have any idea on how to solve this?

Thanks in advance,

Joerg.