How to hide a listitem in dropdownlist control

Hello every one,
 
I am new to this forum,
I like to hide the listitem with text="10" and "9" and "8"
I like to do is
if the textbox1.text="MCA"
 
The listitem presentas a static in a dropodownlist could become hide (it wont visible)
if the  textbox1.text is equal to any thing except "MCA" , the listitems present in the dropdownlist could be visible
 
that's all so please send a code to hide a static listitem having the text="10" and value = "10"
 
<asp:ListItem>10</asp:ListItem> 
By
 
S.Jeevagan 
 
 
 
 
 
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