( others ( ( ( ( have ( ( no effect ) ( on attachment ) ) ) but ) ( ( inhibit ( ( ( fusion ( of ( viral ( and ( cell membranes ) ) ) ) ) and ) ( ( hence entry ) ( of virus ) ) ) ) ( into ( the cell ) ) ) ) ; ) )
(ROOT (S (NP (NNS others)) (VP (VP (VBP have) (NP (NP (DT no) (NN effect)) (PP (IN on) (NP (NN attachment))))) (CC but) (VP (VBP inhibit) (NP (NP (NP (NN fusion)) (PP (IN of) (NP (JJ viral) (CC and) (NN cell) (NNS membranes)))) (CC and) (NP (NP (RB hence) (NN entry)) (PP (IN of) (NP (NN virus))))) (PP (IN into) (NP (DT the) (NN cell))))) (: ;)))
others have no effect on attachment but inhibit fusion of viral and cell membranes and hence entry of virus into the cell;
(ROOT (S (NP (NNP Tamiflu)) (VP (VBZ inhibits) (NP (NP (NN spread)) (PP (IN of) (NP (NN virus))))) (. .)))