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  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdjustmentsInPeriodWeightedAverageGrantDateFairValue" id="mmsi_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdjustmentsInPeriodWeightedAverageGrantDateFairValue" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ShareBasedPaymentArrangementPerformanceSharesAndRestrictedStockUnitActivityTableTextBlock" id="mmsi_ShareBasedPaymentArrangementPerformanceSharesAndRestrictedStockUnitActivityTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ScheduleOfShareBasedPaymentAwardPerformanceSharesValuationAssumptionsTableTextBlock" id="mmsi_ScheduleOfShareBasedPaymentAwardPerformanceSharesValuationAssumptionsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="TargetMember" id="mmsi_TargetMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="MaximumUnitsGrantedMember" id="mmsi_MaximumUnitsGrantedMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="MaximumPotentialSharesGrantedMember" id="mmsi_MaximumPotentialSharesGrantedMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DeferredTaxAssetsStateTaxCreditCarryforwardsResearch" id="mmsi_DeferredTaxAssetsStateTaxCreditCarryforwardsResearch" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element name="ContingentConsiderationPaymentOneMember" id="mmsi_ContingentConsiderationPaymentOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ContingentConsiderationPaymentTwoMember" id="mmsi_ContingentConsiderationPaymentTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ContingentConsiderationPaymentPeriod" id="mmsi_ContingentConsiderationPaymentPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="AssetAcquisitionContingentConsiderationNumberOfAnnualPayments" id="mmsi_AssetAcquisitionContingentConsiderationNumberOfAnnualPayments" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="DeferredTaxAssetsCapitalizedResearchAndDevelopmentExpense" id="mmsi_DeferredTaxAssetsCapitalizedResearchAndDevelopmentExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="EquityMethodInvestmentSharesOwned" id="mmsi_EquityMethodInvestmentSharesOwned" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="AdvancedRadiationTherapyLlcMember" id="mmsi_AdvancedRadiationTherapyLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AngioDynamicsIncMember" id="mmsi_AngioDynamicsIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AssetAcquisitionInProcessResearchAndDevelopmentExpense" id="mmsi_AssetAcquisitionInProcessResearchAndDevelopmentExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="SeniorUnsecuredConvertibleNotesMember" id="mmsi_SeniorUnsecuredConvertibleNotesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="DebtInstrumentRepurchasePercentage" id="mmsi_DebtInstrumentRepurchasePercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DebtInstrumentConversionRatioMultipleOfPrincipal" id="mmsi_DebtInstrumentConversionRatioMultipleOfPrincipal" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="DebtInstrumentCappedCallTransactionCost" id="mmsi_DebtInstrumentCappedCallTransactionCost" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="LineOfCreditFacilityCovenantTermsConsolidatedTotalNetLeverageRatioMaximum" id="mmsi_LineOfCreditFacilityCovenantTermsConsolidatedTotalNetLeverageRatioMaximum" type="xbrli:pureItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LineOfCreditFacilityCovenantTermsConsolidatesSeniorSecuredNetLeverageRatio" id="mmsi_LineOfCreditFacilityCovenantTermsConsolidatesSeniorSecuredNetLeverageRatio" type="xbrli:pureItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ConditionOneForConversionNumberOfDaysAfterAnyTenDaysTradingPricePerShareIsLessThan98OfProductLastReportedSalePriceOfCommonStock" id="mmsi_ConditionOneForConversionNumberOfDaysAfterAnyTenDaysTradingPricePerShareIsLessThan98OfProductLastReportedSalePriceOfCommonStock" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ConditionOneForConversionNumberOfConsecutiveTradingDaysToBeCheckedForTradingPrice" id="mmsi_ConditionOneForConversionNumberOfConsecutiveTradingDaysToBeCheckedForTradingPrice" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="MinimumPercentageOfLastReportedSalePriceOfCommonStockShouldBeForConversionAsConditionOne" id="mmsi_MinimumPercentageOfLastReportedSalePriceOfCommonStockShouldBeForConversionAsConditionOne" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ConditionTwoForConversionDurationInWhichCompanyIssuesStockAtPriceLessThanAverageClosingSalePrice" id="mmsi_ConditionTwoForConversionDurationInWhichCompanyIssuesStockAtPriceLessThanAverageClosingSalePrice" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ConditionTwoForConversionNumberOfConsecutiveTradingDaysToBeCheckedForSharesIssuePriceLessThanAverageClosingRice" id="mmsi_ConditionTwoForConversionNumberOfConsecutiveTradingDaysToBeCheckedForSharesIssuePriceLessThanAverageClosingRice" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ConditionTwoForConversionMinimumPercentageOfPreviousDaySClosingSalePriceToBeForCompanySElectionToDistributeToShareholders" id="mmsi_ConditionTwoForConversionMinimumPercentageOfPreviousDaySClosingSalePriceToBeForCompanySElectionToDistributeToShareholders" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ConditionFourForConversionPercentageOfLastReportedSalePriceExceedingConversionPrice" id="mmsi_ConditionFourForConversionPercentageOfLastReportedSalePriceExceedingConversionPrice" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ConditionFourForConversionThresholdNumberOfDaysLastReportedSalesPriceExceedingPercentageOfConversionPrice" id="mmsi_ConditionFourForConversionThresholdNumberOfDaysLastReportedSalesPriceExceedingPercentageOfConversionPrice" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ConditionFourForConversionThresholdNumberOfConsecutiveDaysLastReportedSalesPriceExceedingPercentageOfConversionPrice" id="mmsi_ConditionFourForConversionThresholdNumberOfConsecutiveDaysLastReportedSalesPriceExceedingPercentageOfConversionPrice" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LastReportedSalesPriceOfStockAsPercentageOfConversionPriceForRedemptionOfDebt" id="mmsi_LastReportedSalesPriceOfStockAsPercentageOfConversionPriceForRedemptionOfDebt" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ThresholdNumberOfDaysLastReportedSalesPriceExceedingPercentageOfConversionPriceForRedemption" id="mmsi_ThresholdNumberOfDaysLastReportedSalesPriceExceedingPercentageOfConversionPriceForRedemption" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ThresholdNumberOfConsecutiveDaysLastReportedSalesPriceExceedingPercentageOfConversionPriceForRedemption" id="mmsi_ThresholdNumberOfConsecutiveDaysLastReportedSalesPriceExceedingPercentageOfConversionPriceForRedemption" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ScholtenSurgicalInstrumentsIncMember" id="mmsi_ScholtenSurgicalInstrumentsIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ContingentConsiderationPaymentThreeMember" id="mmsi_ContingentConsiderationPaymentThreeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NeilPetersonMember" id="mmsi_NeilPetersonMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="RaulParraMember" id="mmsi_RaulParraMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="StockSurrenderedDuringPeriodSharesStockOptionsExercised" id="mmsi_StockSurrenderedDuringPeriodSharesStockOptionsExercised" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="IncreaseDecreaseLiabilityForUncertainTaxPositions" id="mmsi_IncreaseDecreaseLiabilityForUncertainTaxPositions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="CookMedicalHoldingsLlcMember" id="mmsi_CookMedicalHoldingsLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="EndoGastricSolutionsIncMember" id="mmsi_EndoGastricSolutionsIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccruedExpenses" id="mmsi_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccruedExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="EquityAdjustmentsPurchaseOfCappedCallOptions" id="mmsi_EquityAdjustmentsPurchaseOfCappedCallOptions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="AmortizationAndWriteOffOfDebtIssuanceCosts" id="mmsi_AmortizationAndWriteOffOfDebtIssuanceCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ShareBasedCompensationArrangementEmployeeStockPurchasePlanPercentageOfMarketPricePurchaseDate" id="mmsi_ShareBasedCompensationArrangementEmployeeStockPurchasePlanPercentageOfMarketPricePurchaseDate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DavidKFloydMember" id="mmsi_DavidKFloydMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="MichaelRMcdonnellMember" id="mmsi_MichaelRMcdonnellMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AccruedLiabilitiesCurrentMember" id="mmsi_AccruedLiabilitiesCurrentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BiolifeLLCMember" id="mmsi_BiolifeLLCMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PaymentsToAcquireBusinessesUpfrontPayment" id="mmsi_PaymentsToAcquireBusinessesUpfrontPayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="PaymentsToAcquireBusinessesWorkingCapitalAdjustment" id="mmsi_PaymentsToAcquireBusinessesWorkingCapitalAdjustment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="BusinessCombinationRecognizedAssetAcquiredAndGoodwill" id="mmsi_BusinessCombinationRecognizedAssetAcquiredAndGoodwill" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="BusinessCombinationRecognizedLiabilityAssumedAccruedExpensesCurrent" id="mmsi_BusinessCombinationRecognizedLiabilityAssumedAccruedExpensesCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="CashSettledRestrictedStockUnitsMember" id="mmsi_CashSettledRestrictedStockUnitsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="WellsFargoFixedRateDerivativeContractThreeMember" id="mmsi_WellsFargoFixedRateDerivativeContractThreeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BusinessCombinationRecognizedLiabilityAssumedLiabilitiesRelatedToUnrecognizedTaxBenefits" id="mmsi_BusinessCombinationRecognizedLiabilityAssumedLiabilitiesRelatedToUnrecognizedTaxBenefits" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="IncomeTaxRefundReceivables" id="mmsi_IncomeTaxRefundReceivables" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="C2CryoballoonDeviceAndRelatedTechnologyAcquisitionMember" id="mmsi_C2CryoballoonDeviceAndRelatedTechnologyAcquisitionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseLimitOnCompensationPaidToCoveredEmployeeAmount" id="mmsi_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseLimitOnCompensationPaidToCoveredEmployeeAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="EffectiveIncomeTaxRateReconciliationIncomeEarnedByControlledForeignCorporationNetOfAllowableForeignTaxCreditAmount" id="mmsi_EffectiveIncomeTaxRateReconciliationIncomeEarnedByControlledForeignCorporationNetOfAllowableForeignTaxCreditAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="EffectiveIncomeTaxReconciliationChangeInUnrecognizedTaxBenefitsAmount" id="mmsi_EffectiveIncomeTaxReconciliationChangeInUnrecognizedTaxBenefitsAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseLimitOnCompensationPaidToCoveredEmployeePercent" id="mmsi_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseLimitOnCompensationPaidToCoveredEmployeePercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="EffectiveIncomeTaxRateReconciliationIncomeEarnedByControlledForeignCorporationNetOfAllowableForeignTaxCreditPercent" id="mmsi_EffectiveIncomeTaxRateReconciliationIncomeEarnedByControlledForeignCorporationNetOfAllowableForeignTaxCreditPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="EffectiveIncomeTaxReconciliationChangeInUnrecognizedTaxBenefitsPercent" id="mmsi_EffectiveIncomeTaxReconciliationChangeInUnrecognizedTaxBenefitsPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ScheduleOfIncomeTaxesPaidNetTableTextBlock" id="mmsi_ScheduleOfIncomeTaxesPaidNetTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="IncomeTaxReconciliationTaxCreditsAdjustmentOther" id="mmsi_IncomeTaxReconciliationTaxCreditsAdjustmentOther" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="EffectiveIncomeTaxRateReconciliationTaxCreditsAdjustmentOther" id="mmsi_EffectiveIncomeTaxRateReconciliationTaxCreditsAdjustmentOther" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ContingentLiabilityMember" id="mmsi_ContingentLiabilityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="DualCapDisinfectionProtectionSystemMember" id="mmsi_DualCapDisinfectionProtectionSystemMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ProceedsFromSaleOfPropertyPlantAndEquipmentAndDivestitureOfBusinesses" id="mmsi_ProceedsFromSaleOfPropertyPlantAndEquipmentAndDivestitureOfBusinesses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
</xsd:schema>
