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  <element name="IncreaseDecreaseInDeferredTaxLiabilitiesDeferredExpenseReservesAndAccruals" id="md_IncreaseDecreaseInDeferredTaxLiabilitiesDeferredExpenseReservesAndAccruals" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="InterestAndPenaltiesMember" id="md_InterestAndPenaltiesMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="InternalRevenueCodeSection481Member" id="md_InternalRevenueCodeSection481Member" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LongTermDebtAndCapitalLeaseObligationsExcludingLongTermLineOfCredit" id="md_LongTermDebtAndCapitalLeaseObligationsExcludingLongTermLineOfCredit" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LongTermInvestmentsMaturityPeriod" id="md_LongTermInvestmentsMaturityPeriod" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MalpracticeLossContingencyProvisionForLosses" id="md_MalpracticeLossContingencyProvisionForLosses" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ManagementServicesReportingUnitMember" id="md_ManagementServicesReportingUnitMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MaternalFetalMedicineMember" id="md_MaternalFetalMedicineMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MedicalAndOtherEquipmentHeldUnderCapitalLeaseMember" id="md_MedicalAndOtherEquipmentHeldUnderCapitalLeaseMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MoneyMarketFundsAtFairValue" id="md_MoneyMarketFundsAtFairValue" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NeonatologyAndOtherPediatricSubspecialtiesMember" id="md_NeonatologyAndOtherPediatricSubspecialtiesMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NetOperatingLossCarryForwardsExpirationDate" id="md_NetOperatingLossCarryForwardsExpirationDate" type="xbrli:gYearItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NineteenNinetySixNonQualifiedEmployeeStockPurchasePlanAndTwoThousandFifteenNonQualifiedStockPurchasePlanMember" id="md_NineteenNinetySixNonQualifiedEmployeeStockPurchasePlanAndTwoThousandFifteenNonQualifiedStockPurchasePlanMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NineteenNinetySixNonQualifiedEmployeeStockPurchasePlanMember" id="md_NineteenNinetySixNonQualifiedEmployeeStockPurchasePlanMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NumberOfMaternalfetalMedicinePracticesAcquired" id="md_NumberOfMaternalfetalMedicinePracticesAcquired" type="xbrli:integerItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NumberOfNeonatologyPracticesAcquired" id="md_NumberOfNeonatologyPracticesAcquired" type="xbrli:integerItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NumberOfPediatricMultiSpecialtyPracticesAcquired" id="md_NumberOfPediatricMultiSpecialtyPracticesAcquired" type="xbrli:integerItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NumberOfPediatricSubspecialtyPracticesAcquired" id="md_NumberOfPediatricSubspecialtyPracticesAcquired" type="xbrli:integerItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NumberOfPhysicianGroupPracticesAcquired" id="md_NumberOfPhysicianGroupPracticesAcquired" type="xbrli:integerItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NumberOfRadiologyPracticesAcquired" id="md_NumberOfRadiologyPracticesAcquired" type="xbrli:integerItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PatentedAndOtherTechnologyMember" id="md_PatentedAndOtherTechnologyMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PaymentForPurchaseConsiderationRelatedToPriorPeriodAcquisitions" id="md_PaymentForPurchaseConsiderationRelatedToPriorPeriodAcquisitions" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PediatricCardiologyMember" id="md_PediatricCardiologyMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PercentageOfNetPatientServiceRevenueByTypeOfPayor" id="md_PercentageOfNetPatientServiceRevenueByTypeOfPayor" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PhysicianAndHospitalAgreementsMember" id="md_PhysicianAndHospitalAgreementsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PhysicianGroupMember" id="md_PhysicianGroupMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PracticeSalariesAndBenefits" id="md_PracticeSalariesAndBenefits" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PracticeSuppliesAndOtherOperatingExpenses" id="md_PracticeSuppliesAndOtherOperatingExpenses" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PriorPeriodAcquisitionsMember" id="md_PriorPeriodAcquisitionsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ProfessionalLiabilityCoveragePolicyTextBlock" id="md_ProfessionalLiabilityCoveragePolicyTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PropertyPlantAndEquipmentCapitalizedInterestCostsAbstract" id="md_PropertyPlantAndEquipmentCapitalizedInterestCostsAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ProvisionAdjustmentForLossesRelatedToCurrentYear" id="md_ProvisionAdjustmentForLossesRelatedToCurrentYear" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ProvisionAdjustmentForLossesRelatedToPriorYear" id="md_ProvisionAdjustmentForLossesRelatedToPriorYear" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RadiologyAndTeleradiologyMember" id="md_RadiologyAndTeleradiologyMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RecentlyAdoptedAccountingPronouncementsPolicyTextBlock" id="md_RecentlyAdoptedAccountingPronouncementsPolicyTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RedeemUpToThirtyFivePercentageOfAggregatePrincipalAmountMember" id="md_RedeemUpToThirtyFivePercentageOfAggregatePrincipalAmountMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RegulatoryAssetsAbstract" id="md_RegulatoryAssetsAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RestrictedAndDeferredStockUnitsMember" id="md_RestrictedAndDeferredStockUnitsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SaleOfMinorityInterestPercentage" id="md_SaleOfMinorityInterestPercentage" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfAccruedProfessionalLiabilityTableTextBlock" id="md_ScheduleOfAccruedProfessionalLiabilityTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfCapitalLeaseObligationsTableTextBlock" id="md_ScheduleOfCapitalLeaseObligationsTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfFinancingReceivablesLineItems" id="md_ScheduleOfFinancingReceivablesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShortTermInvestmentMaturityPeriod" id="md_ShortTermInvestmentMaturityPeriod" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SixPointTwoFivePercentSeniorUnsecuredNotesDueTwoThousandTwentySevenMember" id="md_SixPointTwoFivePercentSeniorUnsecuredNotesDueTwoThousandTwentySevenMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockIssuedDuringPeriodSharesRestrictedStockAcquisitionConsideration" id="md_StockIssuedDuringPeriodSharesRestrictedStockAcquisitionConsideration" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockIssuedDuringPeriodSharesStockSwaps" id="md_StockIssuedDuringPeriodSharesStockSwaps" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockIssuedDuringPeriodValueRestrictedStockAcquisitionConsideration" id="md_StockIssuedDuringPeriodValueRestrictedStockAcquisitionConsideration" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockIssuedDuringPeriodValueStockSwaps" id="md_StockIssuedDuringPeriodValueStockSwaps" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SummaryOfEstimatedFairValueOfNotesTableTextBlock" id="md_SummaryOfEstimatedFairValueOfNotesTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SummaryOfSignificantAccountingPoliciesLineItems" id="md_SummaryOfSignificantAccountingPoliciesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SummaryOfSignificantAccountingPoliciesTable" id="md_SummaryOfSignificantAccountingPoliciesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="TwoThousandFifteenNonQualifiedStockPurchasePlanMember" id="md_TwoThousandFifteenNonQualifiedStockPurchasePlanMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UnnamedCorporateJointVentureMember" id="md_UnnamedCorporateJointVentureMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UnrecognizedTaxBenefitsImpactEffectiveTaxRate" id="md_UnrecognizedTaxBenefitsImpactEffectiveTaxRate" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UnsecuredRevolvingCreditFacilityMember" id="md_UnsecuredRevolvingCreditFacilityMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
</schema>
