Importing 'n' number of cells in xlsread while n is not constant!

My code is given below

n=caselist(1,1);  
[num, txt] = xlsread('S:/PLOT/PLOT.xlsx', 'B4:B29');

In my data, the start cell (B4) is fixed but the final cell (B29) is not!

So, I'd like to get cells from B4 to B'n' (n: is a variable that points number of cells to be imported).

Answer 1

[Paolo]

 n = caselist(1,1);
 range = strcat('B4:B',num2str(n))
 [num, txt] = xlsread('S:/PLOT/PLOT.xlsx', range);

[ugur uresin]

Thanks in advance!