On finite set-systems whose every intersection is a Kernel of a star

Let k, t be positive integers and let F be a set-system which consists of k-element sets. In this paper it is proved that one can choose a subsystem F^*@?F containing a positive proportion of the members of F, (i.e |F^*| > c(k,t) |F|) and having the property that every pairwise intersection is a kernel of a t-star in F^* (i.e. @?, F'@e F^*, FtnF' = A, @eF"1, ..., F"t @e F^* such that F"i @? F"j = A for 1 =