__DATA__
<enhancement>
<descriptorgroup>
<descriptors type="MED" controlled="y">
<descriptor>
<mainterm weight="a">plague</mainterm>
<mainterm>disease</mainterm>
<mainterm>pestilence</mainterm>
<link>f</link>
<link>C</link>
<link>M</link>
</descriptor>
</descriptors>
<descriptors type="DRG" controlled="y">
<mainterm>panadol</mainterm>
<mainterm weight="a">zorro</mainterm>
<mainterm>xenon</mainterm>
<mainterm weight="a">aspirin</mainterm>
<link>b</link>
<link>P</link>
<link>z</link>
</descriptors>
</descriptorgroup>
</enhancement>