remove objects from stack that are only present in a single section

Hello all, Does anyone know how to remove objects from a stack that are only present in one section of the stack? What I'm doing to detect objects in a thresholded bw image is:

[Clabel,Cnumobj]=bwlabeln(C); %Calculate properties of punctae in C stats_C=regionprops(Clabel,'PixelIdxList','Area'); Cdata=[];

Please be gentle, I'm a MATLAB novice! Thank you, Tara