<?xml version="1.0" encoding="us-ascii"?>
<!-- Prepared by IBM Cognos FSR v6.6.1.124 using Fujitsu Interstage XWand -->

<linkbase xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.xbrl.org/2003/instance http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xmlns="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xbrli="http://www.xbrl.org/2003/instance">
  <roleRef roleURI="http://nbofi.com/role/CONSOLIDATEDSTATEMENTSOFSHAREHOLDERSEQUITY" xlink:type="simple" xlink:href="nbofi-20111231.xsd#nbofi_ELRID_CONSOLIDATEDSTATEMENTSOFSHAREHOLDERSEQUITY" />
  <arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all" />
  <arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension" />
  <arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default" />
  <arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain" />
  <arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member" />
  <definitionLink xlink:type="extended" xlink:role="http://nbofi.com/role/CONSOLIDATEDSTATEMENTSOFSHAREHOLDERSEQUITY">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StatementLineItems" xlink:label="Locator_us-gaap_StatementLineItems_577" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StatementTable" xlink:label="Locator_us-gaap_StatementTable_578" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="Locator_us-gaap_StatementLineItems_577" xlink:to="Locator_us-gaap_StatementTable_578" order="-1.0" xbrldt:contextElement="segment" xbrldt:closed="true" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StatementTable" xlink:label="Locator_us-gaap_StatementTable_581" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="Locator_us-gaap_StatementEquityComponentsAxis_582" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="Locator_us-gaap_StatementTable_581" xlink:to="Locator_us-gaap_StatementEquityComponentsAxis_582" order="0.0" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="Locator_us-gaap_StatementEquityComponentsAxis_557" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="Locator_us-gaap_EquityComponentDomain_558" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="Locator_us-gaap_StatementEquityComponentsAxis_557" xlink:to="Locator_us-gaap_EquityComponentDomain_558" order="2.0" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="Locator_us-gaap_StatementEquityComponentsAxis_583" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="Locator_us-gaap_EquityComponentDomain_584" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="Locator_us-gaap_StatementEquityComponentsAxis_583" xlink:to="Locator_us-gaap_EquityComponentDomain_584" order="0.0" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="Locator_us-gaap_EquityComponentDomain_585" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_CommonStockMember" xlink:label="Locator_us-gaap_CommonStockMember_586" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="Locator_us-gaap_EquityComponentDomain_585" xlink:to="Locator_us-gaap_CommonStockMember_586" order="0.0" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="Locator_us-gaap_EquityComponentDomain_587" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_TreasuryStockMember" xlink:label="Locator_us-gaap_TreasuryStockMember_588" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="Locator_us-gaap_EquityComponentDomain_587" xlink:to="Locator_us-gaap_TreasuryStockMember_588" order="1.0" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="Locator_us-gaap_EquityComponentDomain_589" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_AdditionalPaidInCapitalMember" xlink:label="Locator_us-gaap_AdditionalPaidInCapitalMember_590" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="Locator_us-gaap_EquityComponentDomain_589" xlink:to="Locator_us-gaap_AdditionalPaidInCapitalMember_590" order="2.0" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="Locator_us-gaap_EquityComponentDomain_591" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_RetainedEarningsMember" xlink:label="Locator_us-gaap_RetainedEarningsMember_592" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="Locator_us-gaap_EquityComponentDomain_591" xlink:to="Locator_us-gaap_RetainedEarningsMember_592" order="3.0" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="Locator_us-gaap_EquityComponentDomain_593" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:label="Locator_us-gaap_AccumulatedOtherComprehensiveIncomeMember_594" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="Locator_us-gaap_EquityComponentDomain_593" xlink:to="Locator_us-gaap_AccumulatedOtherComprehensiveIncomeMember_594" order="4.0" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StatementLineItems" xlink:label="Locator_us-gaap_StatementLineItems_595" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StockholdersEquity" xlink:label="Locator_us-gaap_StockholdersEquity_596" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="Locator_us-gaap_StatementLineItems_595" xlink:to="Locator_us-gaap_StockholdersEquity_596" order="1.0" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StatementLineItems" xlink:label="Locator_us-gaap_StatementLineItems_597" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossBeforeTaxPeriodIncreaseDecreaseAbstract" xlink:label="Locator_us-gaap_OtherComprehensiveIncomeLossBeforeTaxPeriodIncreaseDecreaseAbstract_598" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="Locator_us-gaap_StatementLineItems_597" xlink:to="Locator_us-gaap_OtherComprehensiveIncomeLossBeforeTaxPeriodIncreaseDecreaseAbstract_598" order="2.0" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossBeforeTaxPeriodIncreaseDecreaseAbstract" xlink:label="Locator_us-gaap_OtherComprehensiveIncomeLossBeforeTaxPeriodIncreaseDecreaseAbstract_599" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="Locator_us-gaap_NetIncomeLoss_600" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="Locator_us-gaap_OtherComprehensiveIncomeLossBeforeTaxPeriodIncreaseDecreaseAbstract_599" xlink:to="Locator_us-gaap_NetIncomeLoss_600" order="1.0" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossBeforeTaxPeriodIncreaseDecreaseAbstract" xlink:label="Locator_us-gaap_OtherComprehensiveIncomeLossBeforeTaxPeriodIncreaseDecreaseAbstract_601" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax" xlink:label="Locator_us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax_602" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="Locator_us-gaap_OtherComprehensiveIncomeLossBeforeTaxPeriodIncreaseDecreaseAbstract_601" xlink:to="Locator_us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax_602" order="2.0" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StatementLineItems" xlink:label="Locator_us-gaap_StatementLineItems_603" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensation" xlink:label="Locator_us-gaap_AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensation_604" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="Locator_us-gaap_StatementLineItems_603" xlink:to="Locator_us-gaap_AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensation_604" order="3.0" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StatementLineItems" xlink:label="Locator_us-gaap_StatementLineItems_605" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" xlink:label="Locator_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_606" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="Locator_us-gaap_StatementLineItems_605" xlink:to="Locator_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_606" order="4.0" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StatementLineItems" xlink:label="Locator_us-gaap_StatementLineItems_607" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_TreasuryStockValueAcquiredCostMethod" xlink:label="Locator_us-gaap_TreasuryStockValueAcquiredCostMethod_608" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="Locator_us-gaap_StatementLineItems_607" xlink:to="Locator_us-gaap_TreasuryStockValueAcquiredCostMethod_608" order="5.0" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_StatementLineItems" xlink:label="Locator_us-gaap_StatementLineItems_609" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2011/elts/us-gaap-2011-01-31.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue" xlink:label="Locator_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_610" />
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="Locator_us-gaap_StatementLineItems_609" xlink:to="Locator_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_610" order="6.0" />
  </definitionLink>
</linkbase>