One subject term, critical expression, key phrase, abbreviation, indexing word, etc., that is associated with the whole document and can be used for identification, searching, and indexing purposes
Conversion Note: Keywords are not allowed to nest. There are a few journal Tag Sets in which keyword nesting is used to simulate a two-part list. Such a keyword list should be tagged as a Definition List instead.
<!ELEMENT kwd (#PCDATA %kwd-elements;)* >
Any combination of:
<article> <front> ... <abstract>... </abstract> <kwd-group> <kwd>DNA analysis</kwd> <kwd>gene expression</kwd> <kwd>parallel cloning</kwd> <kwd>fluid microarray</kwd> </kwd-group> </article-meta> </front> ...