Jquery过滤select下拉菜单中相同value的option


html:
<select id="loanType" name="loanType" class="inputText rateTempl" onchange="checkWeighing('itemApplyNameNodePath');" validate="{required:true}" style="width:30%;">
 <option value=""></option>
 <option value="1">大额贷款</option>
 <option value="1">大额贷款</option>
 <option value="2">信托合作渠道</option>
 <option value="2">信托合作渠道</option>
</select>

jquery:
function checkWeighing(selectId){
   opts = $("#"+selectId).find("option");
   opts.each(function () {
          optVal = $(this).val();
          if(optVal == ""){
           return true;
          }
          if($("#"+selectId+" option[value='" + optVal + "']").length > 1)
                 $("#"+selectId+" option[value='" + optVal + "']:gt(0)").remove();
      })
  }