REV LTRs work efficiently in human lymphoid cells , and are viable alternatives to promoters commonly used for expression of cloned genes .
rev ltrs work efficiently in human lymphoid cells , and are viable alternatives to promoters commonly used for expression of cloned genes .
B-virus O O O O B-cell_type I-cell_type I-cell_type O O O O O O B-DNA_domain_or_region O O O O O B-DNA_domain_or_region I-DNA_domain_or_region O