2011同等学力英语二卷班——翻译讲义(郭崇兴老师(5)

Oratleastthat’stheargumentputforwardintheNewEnglandJournalofMedicine.Ideally,sayDr.WalterWillettandDr.MeirStampferofHarvard,allvitaminsupplementswouldbeevaluatedinscientificallyrigorousclinicaltrials.Butthosestudiescantakealongtimeandoftenraisemorequestionsthantheyanswer.Atsomepoint,whileresearchersworkonfiguringoutwherethetruthlies,itjustmakessensetosaythepotentialbenefitoutweighsthecost.

Thebestevidencetodateconcernsfolate,oneoftheBvitamins.It’sbeenprovedtolimitthenumberofdefectsin

embryos(胚胎)，andarecenttrialfoundthatfolateincombinationwithvitaminB12andaformofB6alsodecreasesthere-blockageofarteriesaftersurgicalrepair.

ThenewsonvitaminEhasbeenmoremixed.Healthyfolkswhotake400internationalunitsdailyforatleasttwoyearsappearsomewhatlesslikelytodevelopheartdisease.ButwhendoctorsgivevitaminEtopatientswhoalreadyhaveheartdisease,thevitamindoesn’tseemtohelp.ItmayturnoutthatvitaminEplaysaroleinpreventionbutcannotundoseriousdamage.

DespitevitaminC’sgreatpopularity,consuminglargeamountsofitstillhasnotbeenpositivelylinkedtoanygreatbenefit.ThebodyquicklybecomessaturatedwithCandsimplyexcretes(排泄)anyexcess.

Themultivitaminsquestionboilsdowntothis:Doyouneedtowaituntilalltheevidenceisinbeforeyoutakethem,orareyouwillingtoacceptthatthere’senoughevidencethattheydon’thurtandcouldhelp?

Ifthelatter,there’rgedosescancausetrouble,includingexcessivebleedingandnervoussystemproblems.

Multivitaminsarenosubstituteforexerciseandabalanceddiet,ofcourse.Aslongasyouunderstandthatanypotentialbenefitismodestandsubjecttofurtherrefinement,takingadailymultivitaminmakesalotofsense.

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Manfirstappearedonearthhalfamillionyearsago.Thenhewaslittlemorethananimal;butearlymanhadseveralbigadvantagesovertheanimals.Hehadalargebrain,hehadanuprightbody,hehadcleverhands;andhehadinhisbrainspecialgroupsofnervecells,notpresentinanimnals,thatenabledhimtoinventalanguageanduseittocommunicatewithhisfellowmen.71)Thisabilitytospeakwasofverygreatvaluebecauseitallowedmentoshareideas,andtoplantogether,sothattasksalsoenabledideastobepassedonfromgenerationtogenerationsothatthestockofhumanknowledgeslowlyincreased.

Itwasthesespecialadvantagesthatputmenfaraheadofallotherlivingcreaturesinthestruggleforexistence.Theycanusetheirintelligenceagainsttheirdifficltiesandmasterthem.

Sincethosefar—offtimes,whenhefirstappeared,manhasachievedagreatdeal.Hehasusedanimals,steam,electricityandoiltomovehimselfmoreandmorequicklyformplacetoplace.Hehasovercomeriversandseaswithrafts,canoes,boatsandshipsofendlessManfoundthathisownmusclesweretooweakfortheworkwhichhewantedtopower—wind,water,steam,electricity—untilnowhehashishandsontheultimatesourceofphysicalenergy,thenuclearFromman’searliestdaystheflightofbirdshasraisedhiswonderanddesire.Whyshouldhenotflyastheydid?Thenhebegantoexperiment.Atlasthelearnthowtomaketherightmachinestocarryhimthroughtheair.Nowhecanflyfasterthansound.Alreadyhehasplansforconqueringspace,andaseriesofexperimentshasbeenbeforemantakesagiantstepawayfromthisplanetandvisitsthemoon,learningwhatitisliketohavenoweighttohisCommunicationalsopresentedmanwithaproblem.Notlongagoinhistoryeventhemostimprortantmessagetookweekstotravelfromonecountrytoanotherinwrittenformorbywordofmouth;nowajokeonawirelessprogrammeleapsacrosstheworldataspeedof186,000milesahundredsofmilesawayattheverymomentwhentheyoccur.