<script type="text/javascript">
jQuery(function(){

var minimized_elements = $('p.minimize');


minimized_elements.each(function(){
    var t = $(this).text();
    if(t.length < 100) return;

    $(this).html(
        t.slice(0,100) + '<span>... </span><a href="#" class="more">More</a>'+
            '<span style="display:none;">' + t.slice(100,t.length) +
            ' <a href="#" class="less">Less</a></span>'
    );

});

$('a.more', minimized_elements).click(function(event){
    event.preventDefault();
    $(this).hide().prev().hide();
    $(this).next().show();
});

$('a.less', minimized_elements).click(function(event){
    event.preventDefault();
    $(this).parent().hide().prev().show().prev().show();
});
});

<p class="minimize">
    <apex:outputText value="{!Objectlist.Text__c}"/>
</p>

<apex:outputPanel id="panelTest">Above JS function{}</apex:outputPanel>

<apex:commandLink value="Show Less" rerender="panelTest"
     style="width:50%"></apex:commandLink>