The spaces which contain an $S$-space

Dual Banach Spaces Which Contain an Isometric Copy of L1

A Banach space contains asymptotically isometric copies of `1 if and only if its dual space contains an isometric copy of L1.

On graphs which contain all small trees

Communicated by the Managing Editors We investigate those graphs G, with the property that any tree on N vertices occurs as subgraph of G,. In particular, we consider the problem of estimating the minimum number of edges such a graph can have. We show that this number is bounded below and above by $z log II and nl+l/log log %, respectively. A typical question in extremal graph theory1 is one wh...

On Groups which contain no HNN-Extensions

A group is called HNN-free if it has no subgroups that are nontrivial HNN-extensions. 23 We prove that finitely generated HNN-free implies virtually polycyclic for a large class of groups. We also consider finitely generated groups with no free subsemigroups of rank 2 25 and show that in many situations such groups are virtually nilpotent. Finally, as an application of our results, we determine...

On Graphs Which Contain All Sparse Graphs

Cells which contain S-100 protein in Hodgkin's disease: a quantitative study.

Paraffin sections from a series of 50 lymph nodes affected by Hodgkin's disease were examined by means of the unlabelled primary antibody peroxidase-antiperoxidase method to detect those cells which contained S-100 protein. In addition, 15 lymph nodes showing reactive follicular hyperplasia were studied. A simple enumeration procedure (eyepiece graticule) was used to count the number of such ce...