If I understand your question properly, here is what I would do... 
#!/usr/bin/perl

use strict;

while (<DATA>) {
    if (/^\<differentiation\>/ ... /^\<\/differentiation\>/ ) {
        s/\<.*\>/new/g if ! ( /\<differentiation\>/ || /\<\/differenti
+ation\>/ );
        print;
    }
}

__DATA__
<differentiation>
<differentiated-content differentiation="Emphasis3" xlink:type="simple
+">Dedication</differentiated-content>
</differentiation>
<differentiation>
<para differentiation="Emphasis3" xlink:type="simple">Dedication</para
+>
</differentiation>

[download]

In reply to Re: Find and replace by bichonfrise74
in thread Find and replace by Selvakumar

Title:
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