id	keyword
american_scientific_journal-2520	gene
american_scientific_journal-2520	pcr
american_scientific_journal-2520	shpth
american_scientific_journal-2520	primer
american_scientific_journal-2520	hormone
american_scientific_journal-2520	expression
american_scientific_journal-2520	rna
american_scientific_journal-2520	research
american_scientific_journal-2520	time
american_scientific_journal-2520	dna
american_scientific_journal-2520	figure
american_scientific_journal-2520	journal