The Story Line for a Hypothesis Testing Paper: INTRODUCTION: - - PDF document

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The Story Line for a Hypothesis Testing Paper: INTRODUCTION: - - PDF document

Writing a Scientific Research Paper The Story Line for a Hypothesis Testing Paper: INTRODUCTION: Question asked (= hypothesis) * METHODS: Experiment(s) done to


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WritingaScientificResearchPaper

PamelaDerish ScientificPublicationsManager DepartmentofSurgery,UCSF

TheStoryLineforaHypothesisTestingPaper:

INTRODUCTION:Questionasked(=hypothesis) *METHODS:Experiment(s)donetoanswerthequestion(totest thehypothesis) RESULTS:Resultsfoundthatanswerthequestion DISCUSSION:Answertothequestion(=whetherthehypothesis istrue)

TheStoryLineforReviewArticles:

INTRODUCTION:Purposeofthereviewandwhyneededatthis time METHODS:Scopeoftheliteraturesearch(keyterms,inclusive years,etc) RESULTSandDISCUSSION:Mainresultsgatheredanddiscussion

  • fthatinformationtosynthesizethefindingsanddraw

conclusions.

TacklingtheIntroduction…focusing

  • nresearcharticles

TheIntroduction

Hastwofunctions: Awakensthereader'sinterest Preparesreaderstounderstandthepaper Likedescribingtheopeningsceneinaplay…

Introduction (Act 1: Setting the scene)

AwellwrittenIntroductionsets thesceneforthereader.

  • Startsbytellingthereader

whatishappeningorhas happened(thecontext)

  • Endswithaglimpseofwhat

followsintheremainderof thepaper(theplot).

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SLIDE 2

Background, known information Knowledge gap, unknown information Hypothesis, question, purpose statement (Approach, plan of attack, proposed solution)

Introduction flows from broad to narrow (cone or funnel) 1.Backgroundongeneraltopic

Beginbyprovidingthereaderwithbackgroundinformation

  • nthetopicofthepaper.

Describewhatisknownaboutadisease,technique,topic,or compoundandwhyitisanimportanttopic. Makesurethatthebackgroundinformationdirectlyrelates toyourspecificstudy. Example:Ifyouarereportinganewassayforurine

  • xycodone… donotdevoteunnecessarytexttothe

epidemiology,statistics,morbidity,andsocietalcostsofdrug abuseingeneral.Gettotheknowninformationaboutthe needtodetectormonitoroxycodoneassoonaspossible. Example: Ifyouarereportinganewmarkerforpancreatic cancer…donotdevoteunnecessarytexttotheepidemiology, therapy,lifeexpectancy,andmedicalcostsofcancerin general.Gettotheknowninformationaboutpancreatic cancerassoonaspossible.

2.Knowledgegap,unmetneed

Narrowtheintroduction Focusthereadersattentionon: Theimportanceofcontinuedresearch Neededbutunknowninformation Anunsolvedproblem Aknowledgegap Limitationsofpriorstudies. Examples: Appropriateanalyticaltechniqueoranimalmodelmaybelacking. Theproblemhasgoneunrecognizedorapossiblesolutionmissed. Usingtheanalogyofatheatricalproduction,youshouldsetthe scenebyputtingthenecessarybackgroundinformationintothe propercontext.

3.Hypothesis,question,purposestatement

NownarrowtheIntroductionagainbyfocusingonthegoalof yourstudy(theplot). Fromthispointon,thetextmustprovideaclearrationaleforwhyyou undertookthestudy.Youtestahypothesis,answeraquestion,solvea problem,orfulfillapurpose. Thetextshouldincludeastatementthatmakesthiscleartothereader…

3.Hypothesis,question,purposestatement

Thatstatementcanbeoneofthefollowing:

  • Ahypothesisstatement:

Wehypothesizedthat… Wetestedthehypothesisthat...

  • Aquestion:

Weaskedwhether... Toanswerthisquestion,... Thispromptedustoinvestigatewhether... Toresolvethisapparentdifference...

  • Apurposestatement:

Thepurposeofourstudywas..

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General topic or problem: Sepsis is a major cause of morbidity and mortality in individuals who share contaminated needles. Knowledge gap, unknown information: No preventive treatment has been identified. Can statins help? Animal trials suggest yes. But studies in humans are limited. Previous human trials were small, observational, with only one population based cohort study. Purpose statement: Therefore, our aim was to assess the effect of treatment on the rates of sepsis in a prospective cohort study of individuals who had a history of sharing needles.

Example

Sometimesitishelpfultogiveabriefideaofthe methodorprotocolusedinthestudy.Butsave detailsfortheMethodssection. Examples:

Inthisstudy,weasked whetherstudyparticipants understoodtheelementsofinformedconsent,as measuredby recallofthecontentsoftheinformed consentdocument. Usingarandomizedcontrolprotocol thatincludedmonthly blooddrugmeasurements,weinvestigated whether….

Importanceoftransitionphrases/words

Transitionphrasesandwordsallowtheauthortoemphasize importantpoints,andalsohelpthereaderdifferentiate the known,theunknown,thequestion,andtheexperimental approach.

Transitionphrasesandwords

Examplesthatcanbeusedtohighlighttheknown,orlinkthe knowntotheunknown:

  • Thesepriorstudiesshowthat...
  • Supportingthetheorythat...
  • Thesestudiesareimportantbecause...
  • Interestingly,...
  • Moreimportantly,...
  • Usingthisinformation,...
  • Yet,...
  • Unlike...
  • Whereasithasbeenshownthat...
  • Ontheotherhand,...
  • Itisunclear...
  • Thequestionremains,however,…
  • Althoughpriorstudiesdemonstrated...

Additionaltransitionphrases

Examplesoftransitionphrasesthatcanbeusedtoleadintothe question,hypothesisorpurpose: Wehypothesizedthat... Wetestedthehypothesisthat... Weaskedwhether... Toanswerthisquestion,... Thispromptedustoinvestigatewhether... Toresolvethisapparentdifference... Thepurposeofourstudywas... Thistypeofpresentationtellsthereadertoexpectaclearanswer by theendofthearticleregardingthestudygoalsorhypothesis i.e., true/false,yes/no,works/doesn’twork.

Introductionstendtobetoolongratherthantooshort

Alongintroductionislikeacourtroomscene,whereanattorney keepsfeedingstatementstoawitnessuntilthefrustratedjudge asks,"Counselor,isthereaquestionintheresomewhere?"

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Waystoavoidgivingtoomuchinformation

  • 1. Characterizetheaudienceoftheselectedjournal.

Howmuchinformationisreallyneedtounderstandthestudy questionandwhyitmatters? 2.Gobackintimeonlyasfarasneededtobringthereaderup tospeed. Unlessaseminalwork,ismentionofolderworkoranolder referencenecessary?

CreatetheIntroductionbyansweringquestions

Introduction: Whatistheoveralltopicofmypaper? WhatspecificaspectdidIstudy? Whatproblemneededtobeaddressed? Whatwasmyquestion,hypothesis,goal? Example: Burninjury Mechanismoftissuedamageafterthermalburn Whetherfreeradicalscontributetoinflammation Doantioxidants(e.g.,vitaminE)affectinflammation?

Introduction:WritingTips Introduction:WritingTips

Length: Asshortaspossible,consistentwithclarityand informativeness. Typicaljournalarticle:1doublespacedpage(250300words)is

  • ftensufficient.

Forlongerintroductions: 2doublespacedpages(500600 words)isaslongasitshouldbe.

Introduction:WritingTips

Backgroundstatement(s):shouldrelateonlytothespecific subjectofthepaper. Gapthatyourstudyfills:citepreliminaryreportsorabstractsor closelyrelatedpublishedwork,butavoidusingthenamesof investigators.Mentioningothersbynamedoesnthelpyou hook thereader.

Introduction:WritingTips

Biggestproblemislackoffocus,attributableto... Toomuchbackground:Literaturenotcitedselectively (briefly)enough.Focusonthefindings,notthedetailsor names/dates. Problems/flawsinpreviousstudiesnotclearlyidentified (importantifyourworkisanimprovement). Unclearwhatpreviousworkwasyours. Weakormissingpurposestatement.

Introduction:WritingTips

PreviousStudies:focusonthefindings,notnames&dates. Unhelpful:AstudybyJohnsonetal.in1998,reviewedthe medicalrecordsofNavyrecruitswhowereunabletocomplete basictraining. Helpful:Injuryratesforrecruitsundergoingbasictrainingwere 12%peryearin1997fortheAustralianArmyandRAAF,butmuch higherat47%fortheNavy(1).

Adapted from p. 53 of Peat J, Elliot E, Bauer L, Keena V. Scientific Writing: Easy When You Know How. London, UK: BMJ Books; 2002. (Anne Marie Weber-Main, PhD: U Minn)

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Introduction:WritingTips

PreviousStudies:Focusonthefindings Toodetailed:Therehavebeensixpreviousstudiesinthisarea. Henderson,inastudyofdrugusersfromFrance, found….Miller,studying45drugusersinMilwaukee, showed….Kazanfollowed211drugusersandfound… Synthesize:Previousstudiesonneedlesharinghavehad conflictingresults,somesuggestingthat…whereasothersfound that… Previousstudies:identifyflaws (ifyourresearchisan improvement).

Example Previousresearchdidnotaccountforthepossiblesideeffects of priorhistoryofstroke,orhave100%completefollowup.To addresstheseproblems,we…

Introduction:WritingTips

Previousstudies:identifyflaws

Example Moststudiesdidnotmeasuretheactualenvironment experiencedbya patient;instead,thesestudiesusedproxymeasurementsofthis environment,suchasaveragemonthlyoccupancyrates,orcompared weekendwithweekdayadmissionsasasurrogateforhighandlow workloadsperprovider,respectively.

Introduction:WritingTips Introduction:WritingTips

Statethespecifichuman(oranimal)populationstudied: Thepurposeofthisstudywastodeterminetherelative contribution ofsharedneedleusetosepsisandviral infectioninpatientswithahistoryofintravenousdrug use.

Introduction:WritingTips

Beconsistentandcontinuousinyouruseofkeyterms. Keyterms… nameimportantideasinthepaper… canbetechnical:Gprotein mitogenesis canbenontechnical:increase function shouldberepeatedexactly fromsentencetosentenceand paragraphtoparagraph,andintheTitle,Abstract,and differentsectionsofthepaper.

Classparticipation

ReadtheIntroductiononthenextslideandidentifykey termsthatarerepeated.

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Classparticipation

ReviewofSampleIntroductions 1) “BipolarDisorder”byAliza Norwood(reviewarticle) 2) “MZHepatitisB”byLeslieSheu (researcharticle)

TheResultsSection

Question: Whynotjustprovidefiguresandtableswithclear titlesandinformativelegends? Answer: Datadonotspeakforthemselves. Youmustcommunicateyourunderstandingand interpretationofyourdatatothereader.

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TheResultsSection

Statestheresultsoftheexperimentsor studies. Onlyreportsresultspertinenttothe questionraisedintheIntroduction. Directsthereadertofiguresortablesthat presentsupportingdata.

TheResultsSection

Presentingyourresultsislikeplayingacardgame. PresentingYourResults

Example:Onewinningsetofcardsisthestraight,definedas 5consecutivelysequencedcards(e.g.,1,2,3,4,5).

PresentingYourResults

Butyouwouldnotstatethatyouhavethe1,2,3,4,and5

  • fclubs.Thecardsareyourdata.Yourresultisastraight.

Yourresultisyourhandbeatsanotherhand.

Dataandresultsarenotthesame!

Data arefacts,numbers,observations… Usuallypresentedintablesandfiguresasrawdata(individualdata points)orsummarizeddata(mean,percent,medianandrange). Results arestatementsinthetextthatinterpretorexplainwhatthedata show. Authorserrmostoftenbyofferingthereaderdatabutnoresults.

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Sixmonthsafterdiagnosisandinitiationof treatment,thesurvivalrateswere95%forthe Neuroxomabgroup,91%fortheBlasteride group,and39%fortheradiationtreatedgroup (Fig.1).At12monthstherateswere83%,69%, and23%;at18months74%,17%,and15%; andat24months70%,11%,and9%.

Thisparagraphprovidesdatabutnoresults: Whatdothedatashow? Whatisthepoint? Arethetreatmentgroupsdifferentat6months?

Sixmonthsafterdiagnosisandinitiationof treatment,thesurvivalrateswerehigherin theNeuroxomabandBlasteridetreatment groupsthanintheradiationtreatmentgroup (Fig.1).At12,18,and24monthsthesurvival ratesintheNeuroxomabgroupexceeded thoseofboththeBlasterideandradiation treatmentgroups.

Thisparagraphcontainsminimalexplanationofwhatthedata show: HowmuchhigherwerethesurvivalratesfortheNeuroxomab andBlasteride groupsthantheradiationgrouporeachother?

Sixmonthsafterdiagnosisandinitiationoftreatment, the survivalratesfortheNeuroxomabandBlasteride groupswere 2.4and2.3timeshigher,respectively, thantheradiationtreatment group(bothP<0.001), butsurvivalratesdidnotdifferbetweenthe NeuroxomabandBlasteridegroups(P= 0.56)(Fig.1). By12months,however,patientsurvivalin the Neuroxomabgroupwas1.2timeshigherthaninthe Blasteride group(P=0.031),and4.3and6.4times higherat18and24 months(bothP<0.001).

Thisparagraphexplainswhatthedatashow: Themagnitude(e.g.,2.4timeshigher)ofthemost importantdifferences Whenthedifferencesoccurred Whethertheywerestatisticallysignificant

Sixmonthsafterdiagnosisandinitiationoftreatment, survivalratesintheNeuroxomabandBlasteridegroups (95%and91%,respectively)were2.4and2.3times higherthanthesurvivalratefortheradiation treatment group(bothP<0.001),butsurvivalratesdid notdifferbetweentheNeuroxomabandBlasteride groups(P=0.56)(Fig.1).By12months,however,the patientsurvivalrateintheNeuroxomabgroupwas1.2 timeshigherthanintheBlasteridegroup(83%vs69%, P=0.031),adifferencethatbecameevengreaterat18 and24months(74%vs17%and70%vs11%;bothP< 0.001).

Thisparagraphexplainswhatthedatashowandprovidessome importantdatafromthefigure: Includestheactualsurvivalrates(e.g.,95%,91%,and39%at6 months)inadditionthemagnitudeofanydifferences. Table1.Patientsurvivalratesafter3differenttreatmentregimens.

Survival,%

__________________________________________________________________________________________

Time,months Neuroxomab Blasteride Radiation 6 951,2 911 39 12 831,3 691 23 18 741,4 17 15 24 701,4 11 9

Themaintextdescribestheresults,butdoesnotduplicatethedata: Sixmonthsafterdiagnosisandinitiationoftreatment,thesurvivalratesforthe Neuroxomab andBlasteride treatmentgroupswere2.4and2.3timeshigher thanfortheradiationtreatment group,butsurvivalratesdidnotdifferbetween theNeuroxomab andBlasteride groups(P=0.56)(Table1).By12months, however,patientsurvivalintheNeuroxomab groupwas1.2timeshigherthanin theBlasteride group,adifferencethatbecameevengreaterat18and24 months.

1 P<0.001vsradiationgroup.2P=0.56vsBlasteride.3 P=0.031vsBlasteride.4 P<0.001vsBlasteride.

Dataintablesshouldnotberepeatedinthe maintext.

Oneexception: Ifatablesuppliesaverylargeamountofdata,itis acceptabletorestateakeypieceofdatainthetext,suchas the2groupsinthetablewithstatisticallysignificant differences. Onlydothisifithelpsthereaderzeroinonanimportant resultwithouthavingtoplowthroughalonglistofdata.

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SLIDE 9

TheResultsSection

Optionsforpresentationorderofresults:

  • 1. Chronologicalorderwithsubheadingsthatparallelthe

methodsandtheirsequencepresentedearlierinthepaper. Allowsreaderstomoreeasilygobackandrefertothe methodsassociatedwithagivenresult. Example: OrderofMethods OrderofResults Extractionprotocols Extractionprotocols Derivatization reagents Derivatization reagents Chromatographicmethods Chromatographicmethods

TheResultsSection

Optionsforpresentationorderofresults:

2.Mosttoleastimportant Putresultsthatanswerthequestionatthebeginning

  • fthefirstparagraphoftheResultssection.

Example: Therewasadirectcorrelationbetweenbloodmercury concentrationsandneuronalfiberunwinding(Fig.1).

TheResultsSection

Optionsforpresentationorderofresults:

3.Groupingbytopicorexperiment Example:Comparisonof3techniquesforpostmortem toxicology Groupedbytopic(technique):

  • Capillaryelectrophoresis:detectionrate,interferences,cost.
  • Liquidchromatography:detectionrate,interferences,cost.
  • Gaschromatography:detectionrate,interferences,cost.

Readercanseetheresultsforeachtechniqueasapacketof information– alogicalwaytorememberinformation.

TheResultsSection

Nodiscussion!

Thereisatemptationtocommentontheresults. TheanalysisoftheresultsbelongsintheDiscussionsection. IntheResultssectionyoudescribewhatthedatashow;inthe Discussionsectionyoudescribewhatthedatamean.

Classparticipation

Review&critiquetheResultssectionofthesamplepaper fromoneofyourcolleagues: Doesitreportonlyresultsthatarerelatedtothestudy questionattheendoftheIntroduction? Doesitemphasizeresultsratherthandata? Howareparagraphsorganized? AnswersquestionorhypothesisposedinIntroduction. Relatesfindings/conclusiontoexistingknowledge. Supportsyourpointandyourconclusions.

TheDiscussionSection

YourClosingArgument

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TheDiscussionflowsfromnarrowtobroad (invertedcone,funnel)

Answertothequestion Howanswerissupportedbyyourresults Howyourresultsrelatetootherstudies Contributionyourstudymakestothefield (Summary,conclusion)

Howdoesthisstructuredifferfrom thatoftheIntroduction?

Getstartedbyaskingthesequestions:

Whatexactlydidthestudyshow? Whatmightthatmean? Howelsecouldtheresultsbeinterpreted? Haveotherstudieshadsimilarresults,oristhere disagreementinthefield? Whatarethestudy'sstrengthsandweaknesses? What,exactly,shouldhappennext?

TheDiscussionisastory thatconsistsofthe following:

Beginning: Theanswertothestudyquestion (andthekeyevidencethatsupportstheanswer) Middle: Explaining/defendingtheanswer Explainingconflictingresults Secondaryfindings Limitations End: Conclusionandimplications

TheDiscussionpicksupwheretheIntroductionleavesoff.

EndoftheIntroduction: Wethereforeinvestigatedwhetherintravenous4methylpyrazole (fomiprazole)wouldattenuatethemetabolicacidosisandpreventthe renaltubulardamageassociatedwithethyleneglycolintoxication. BeginningoftheDiscussion: Inthisstudy,weinvestigatedwhetherintravenous4methylpyrazole (fomiprazole)wouldattenuatethemetabolicacidosisandpreventthe

  • renaltubulardamageassociatedwithethyleneglycolintoxication. Our

resultsshowthat….

ThefirstparagraphoftheDiscussionshouldbevery specificandfocused.

Getrighttothepoint,whichistoanswerthequestions(s) presentedintheIntroduction. …theanswertothequestionistheculminationofthe paper.Itdeservesthemostprominentpositioninthe Discussion—thebeginning.

Zeiger M.EssentialsofWritingBiomedical ResearchPapers.NewYork:McGrawHill;2000.

Inthisstudy,weinvestigatedwhetherintravenous4 methylpyrazole(fomiprazole)wouldattenuatethemetabolic acidosisandpreventtherenaltubulardamageassociatedwith ethyleneglycolintoxication.Ourresultsshowthat 4 methylpyrazole,whengiven3hoursafterethyleneglycol ingestion,canreducethedegreeofmetabolicacidosisbymore than85%andrenaltubulardamageby90%comparedwith dialysisalone.

Answertothequestion

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SignaltheAnswer

Thisstudyindicatesthat Theresultsofthisstudyshowthat Inthisstudy,wehaveshownthat Inthisstudy,weprovideevidencethat

LinkResultstotheAnswerTheySupport

Inourexperiments, Inourpatients, Theevidenceisthat (Answer)hasbeendemonstratedintwoways

DoNOTbegin…

Withasecondintroduction Withasummaryoftheresults Withsecondaryinformation

Support,explanationanddefenseoftheanswer Unexpectedfindings…Conflictingfindings…Secondaryfindings Subgroupfindings(effectmodifiersofsinglemostimportantfinding: menvs.women;youngvs.old) Findingsthatcontradictotherstudies,conventionalwisdom. Limitations(ofmethods,ofstudydesign),andassumptions—as needed.

ThemiddleoftheDiscussioncancovermanypoints.

Supportfortheanswerusuallycomesatthebeginningofthe Discussion,inthefirstparagraph,withtheansweritself. InthemiddleoftheDiscussion,youmayalsoneedtoexplain

  • rdefend theanswer:

Whyisitreasonable? Howdoesitfitinwithpreviousstudiesonthetopic?

Explainordefendtheanswer. Explaintheanswer.

BeginningofDiscussion:Consistentwithourhypothesis,wefound mentalillnesstobeanindependentriskfactorforunintentional injuryandinjuryrecidivism.Thementallyillwereadmittedfor unintentionalinjurytwiceasoftenasthosewhowerenotmentally

  • ill. Surprisingly, mentalillnesshadsignificantlyhigheroddsof

unintentionalinjuryrecidivismthaneithersubstanceabuseor homelessness. MiddleofDiscussion:Theexplanation forincreasedriskof unintentionalinjuryinthementallyillmaybebasedonchangesin perceptionandawareness.Thesechangesarehallmarksofmany mentalillnesses.Forinstance,….

Showhowtheanswerissupportedbyresults.

Ourfirstfindingthat 4methylpyrazoledecreasesrenaldamageis supportedbyourmeasurementsofbothurinaryoxalateexcretion andrenaltubularoxalateconcentrations.Twentyfourhoursafter infusionof4methylpyrazole,urinaryoxalateexcretionwasreduced by88%comparedwithdialysistreatment,andrenaltubularoxalate concentrationswerereducedby78%comparedwithdialysis. Our findingthat 4methylpyrazoledecreasesrenaldamageisalso supportedbyurineproteinexcretionpatterns,whichshowedno statisticallysignificantdifferencefromhealthycontrols. Oursecondfindingthat 4methylpyrazoledecreasesthedegreeof metabolicacidosisissupportedbyourinlinebloodpH measurements,whichshowedchangesoflessthan0.2pHunits duringtherapeuticintervention.

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Evidenceof acompetitiveeffectof4methylpyrazoleon ethyleneglycolmetabolismbyalcoholdehydrogenasecomes fromapreviousstudy(3).Thatstudyshowedthatinhealthy volunteers,oraldosesof4methylpyrazole(10to20mg/kg) significantlyreducedtherateofeliminationofmoderatedoses

  • fethanol,whichisalsometabolizedthroughtheactionof

alcoholdehydrogenase.Twostudies(4,5)havedemonstrated that4methylpyrazoleplasmaconcentrationsofapproximately 10µmol/L(0.82mg/L)inmonkeysaresufficienttoinhibit methanolmetabolismtoformate,whichisalsomediatedby alcoholdehydrogenase.

Showhowyourresultsrelatetothosefromotherstudies. Showthecontributionyourstudymakestothefield.

Ourdemonstrationthat4methylpyrazoleblocks ethyleneglycolmetabolismmediatedbyalcohol dehydrogenasesupportstheadditionofthiscompetitive inhibitortotheexistingrepertoireofagentsthatcan addtotheeffectivenessofdialysisforthetreatmentof solventingestion.Thefactthatnoneofthepatients whoreceived4methylpyrazoleshowedanyallergicside effectssupportsthesafetyofthiscompoundin emergencysituations.

Discusssecondaryfindings.

FirstParagraph: Inthisstudy,weshowedforthefirsttime thatthe Cul4A geneisamplifiedinhumanmesotheliomacelllines.Consistent withgeneamplification,overexpressionofCul4Aproteinwasobserved inmesotheliomacelllinesandMPMtissues.Furtherknockdownof Cul4AbyshRNA inmesotheliomaalsoinhibitedmesotheliomacell growth.Thus,ourresultsindicate thatamplificationoftheCul4A gene maybeanimportantoncogeniceventinmesotheliomadevelopment. SecondParagraph: Wealsoobserved thatdownregulationofCul4A withshRNA causescellcyclearrestandgrowthinhibitionthroughup regulationofp21andp27proteinsinap53independentmannerin mesotheliomacells.Severallinesofevidencesupportthishypothesis. First,

Discusssubgroupfindings.

Theeffectsweobserved—reducedtumorproliferation, decreasedtumorsize,andincreasedapoptoticactivityafteronly 36weeksoffluvastatin treatment—wereonlyevidentin subjectswithhighgradetumors,whichsuggeststhesignificant differencesinresponsewereprimarilyduetotumorgrade, ratherthanestrogenreceptor(ER)status. Althoughtheworstoutcomeswerepredominantlyinsubjects withERnegativetumors,somewereinsubjectswithhighgrade ERpositivetumors,furtherevidenceindicatingthatgrademay bemoreimportantthanERstatusindeterminingtumorresponse tofluvastatin.

Don’tforgetunexpectedfindings,andtry toexplainthem.

Asurprisingfinding wasthatinmicetreatedwithisoproterenol,

  • xygenextractionratiosduringseverehypoxiawerelow.Theratios

wefound werelessthan40%,whereasratiosinuntreatedmice rangefrom8090%(2).Wesuggesttwopossibleexplanations of whyextractionofoxygenfromskeletalmusclewasnotfurther increasedtominimizetheoxygendeficitinthemicetreatedwith isopreterenol.First,bloodflowmayhavebeendirected…Second, somemetaboloic autoregulatory stimulusmayhave…Ifthese explanationsarecorrect,theyimplythattheoxygendeficitislinked notonlytooxygendeliverybutalsotosometissuesignal

  • riginatingatthecellularlevel.

Discussconflictingfindings.

Themainfindingofourstudyis thatßadrenergicblockade doesnotimpairperformanceofmaximalorsubmaximal exerciseathighaltitude.Asexpected,treatmentwiththeß blockerpropanalolsignificantlydecreasedheartrateathigh altitude.However,contrarytoourhypothesis,subjects treatedwithpropanololcouldmaintainlevelsofoxygen uptakeduringmaximalandsubmaximalexerciseasgreatas thoseinsubjectstreatedwithplacebo.Thisfindingcannotbe attributed toincreasedarterialoxygensaturationor hemoglobinconcentration…Rather,itappears thatoxygen uptakewasmaintainedbyincreasingstrokevolume.

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Discussfindingsthatcontradictthose fromotherstudies.

Thoughourresultsmayseemtodiffer fromthoseof Haleyetal.(21),weusedadifferentmethodof ascertainingcompliancewiththerapythantheydid. Apparentdiscrepancies betweenourhumangrowth hormonevaluesandthoseofearlierstudiesmaybedue todifferencesinstudydesign.Inourstudy,allsubject workedatthesamerelativeintensity,etc…

UseYourWorktoSupportPreviousStudies.

Thefactthatourstudywasprospectivelendssupport totheevidenceofacausalroleofsleepdisordered breathinginhypertension.Wefoundthatthepresence

  • fsleepdisorderedbreathingwaspredictiveofhypertension

fouryearslater.

UseOthers WorktoSupportYourStudy.

Previousstudies ofthehemodynamiceffectsofintravenous andoralsildenafilinnormalmenandmen withstableischemicheartdiseasehavedemonstrated asmallbutconsistentdecreaseinsystemicandpulmonary bloodpressureafteradministrationofthedrug.(refs)The resultsofourstudyconfirmthesefindings inmenwith anatomicallyseverecoronarydisease.Inaddition,we investigatedtheeffectsofsildenafiloncoronary hemodynamics.

Findtherightword(s)toexplaintherelationship betweenyourworkandpreviouswork…

This/Ourstudy/method/result/approach… isanalogousto iscomparableto iscompatiblewith isconsistentwith contrastswith isinlinewith issignificantlydifferentfrom isthefirstofitskind is(very)similarto

Findtherightword(s)toexplaintherelationship betweenyourworkandpreviouswork…

This/Ourstudy… broadens/challenges/confirms/contradicts/correspondsto/ corroborates/differsfrom/extends/expands/goesagainst/ lendssupportto/modifies/providesinsightinto/provides supportfor/refutes/tendstorefute/verifies

Findtherightword(s)toexplaintherelationship betweenyourworkandpreviouswork…

Ourresultsareingeneralagreementwith thosefrom previousmorphometricandDNincorporationstudiesinthe rat[2,6]. Ourcurrentfindingsexpand priorwork[5]inshowing… Unlike McGowan,wedidnotidentify9cis RAinthe mouselung.

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SLIDE 14

Befairandbalanced.

Ifothers'resultshelpsupportyouranswer,mentionthemandcitethe appropriatereferences. Giveappropriatecredittoyourselfaswell,butavoidclaimingpriority (inmostcases).

Ofthe4publishedprocedures fornucleicacidinsertion, wechosetheonedescribedbyWallenburgandHughesbecause their procedureyieldsthehighestpercentageofcDNAtransfectedviruses.Other researchershavesuccessfullyusedthesameproceduretogenerateviral vectorsfortheinvivoproductionofferritinandtranscobalamin,2smaller proteinswithmolecularweightsinthesamerangeasour3proteins.We wereabletoimprovetheyield oftransfectedviruses2foldbyadding0.01% glyceroltothetrypsinEDTAsolution.

Explainlimitationsofyourstudy.

Werecognizelimitationsofourstudy… Ourstudyhassomelimitations Onelimitationofourstudyis…

Nostudyiswithoutpotentialbias Nostudyisperfectlyexecuted Nostudyisdefinitive Headcriticismoffatthepass Example:Alimitationtointerpretinglongtermsuccesswasthat30%of patientswhohadingestedethyleneglycolandreceived4methylpyrazoledid notcompletethe6monthfollowup.

Trytopresentlimitationwith“redemption”.

Oneassumptionwemadeforthemeasurementofthe pulmonarycapillaryfiltrationcoefficientwasthatisolating thelungsdidnotinjurepulmonaryvessels.Thisisa reasonableassumptionbecause weminimizedlungischemia byremovingthelungsrapidly(within5min).Inaddition,the baselineKf valuesinourstudyarelowandagreewiththose inotherreports(2).

ContinuityisEssential

Becausethemiddlecanbeseveralparagraphs,organizationand continuityareimportanttokeepthestoryflowingwell:

Organizethetopics eitheraccordingtothescienceorfrommosttoleast important. Usetopicsentencesatthebeginningofeachparagraph totellastory! Eachtopicsentencestatingthemessageorthetopicofthe paragraph;detailsinlogicallyorganizedsupportingsentences. Trytolinkeachtopicsentencelinkedtothepreviousparagraphby arepeatedkeyterm atransitionword both+theothertechniquesofcontinuityasneeded

Forcontinuity,usetopicsentencesatthebeginningof eachparagraphtotellastory.

Seriesoftopicsentencesfor1study(keytermsrepeatedtoo):

1) Inthislongterm,multicenter,randomizedtrialinvolvingpatientswith abdominalaorticaneurysm,therewasnosignificantdifferenceinthe primaryoutcomeoflongtermallcausemortalitybetweenthe endovascularrepairgroup andtheopenrepairgroup. 2) Aneurysm ruptureafterrepair wasuncommonbutoccurredonlyinthe endovascularrepairgroup,resultinginasignificantbetweengroup difference. 1) Muchoftheearlyenthusiasmforendovascularrepair focusedonthe expectedadvantageamongoldorinfirmpatientswhowerenotgood candidatesforopenrepair.

Cometoadefinite end:

  • 1. Restatetheanswertothequestion.
  • 2. Signaltheend byusingaphrasesuchas"Inconclusion",
  • r"Insummary,soreaderswillknowthisistheanswer.
  • 3. Thenindicatetheimportanceoftheworkbybriefly

statingapplications,recommendations,implications,or speculations.

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SLIDE 15

Sources(manyarealsogoodresourcesforyoutohave)

Annesley TM. Deputy Editor, Clinical Chemistry and Professor, University of Michigan– see his series covering all aspects of preparing and submitting a paper for publication at http://www.aacc.org/publications/clin_chem/ccgsw/Pages/default.aspx Browner WS. Publishing and Presenting Clinical Research. Baltimore: Lippincott Williams & Wilkins, 1999. Derish PA and Eastwood S. A Clarity Clinic for Surgical Writing. J Surg Res 2008, 147:50-58. Goodman NW, Black A. A Prescription for Clarity: A Self-Help Guide to Clearer Medical English. London/New York, Cambridge University Press, 1997. Peat J, Elliot E, Bauer L, Keena V. Scientific Writing: Easy When You Know How. London, UK: BMJ Books; 2002 (pdf version available online!) Rutherford G. Cavtat Scientific Writing Workshop, June 27-July 1, 2005 (with permission) Zeiger M. Essentials of Writing Biomedical Research Papers (second edition). New York: McGraw-Hill, 1999.