考研英语阅读分析详解例13
<p> <span word="Until">Until</span> <span word="about">about</span> <span word="five">five</span> <span word="years">years</span> <span word="ago">ago</span>, <span word="the">the</span> <span word="very">very</span> <span word="idea">idea</span> <span word="that">that</span> <span word="peptide">peptide</span> <span word="hormones">hormones</span> <span word="might">might</span> <span word="be">be</span> <span word="made">made</span> <span word="anywhere">anywhere</span> <span word="in">in</span> <span word="the">the</span> <span word="brain">brain</span> <span word="besides">besides</span> <span word="the">the</span> <span word="hypothalamus">hypothalamus</span> <span word="was">was</span> <span word="astounding">astounding</span>. <span word="Peptide">Peptide</span> <span word="hormones">hormones</span>, <span word="scientists">scientists</span> <span word="thought">thought</span>, <span word="were">were</span> <span word="made">made</span> <span word="by">by</span> <span word="endocrine">endocrine</span> <span word="glands">glands</span> <span word="and">and</span> <span word="the">the</span> <span word="hypothalamus">hypothalamus</span> <span word="was">was</span> <span word="thought">thought</span> <span word="to">to</span> <span word="be">be</span> <span word="the">the</span> <span word="brains">brains</span> <span word="only">only</span> <span word="endocrine">endocrine</span> <span word="gland">gland</span>. <span word="What">What</span> <span word="is">is</span> <span word="more">more</span>, <span word="because">because</span> <span word="peptide">peptide</span> <span word="hormones">hormones</span> <span word="cannot">cannot</span> <span word="cross">cross</span> <span word="the">the</span> <span word="blood">blood</span>-<span word="brain">brain</span> <span word="barrier">barrier</span>, <span word="researchers">researchers</span> <span word="believed">believed</span> <span word="that">that</span> <span word="they">they</span> <span word="never">never</span> <span word="got">got</span> <span word="to">to</span> <span word="any">any</span> <span word="part">part</span> <span word="of">of</span> <span word="the">the</span> <span word="brain">brain</span> <span word="other">other</span> <span word="than">than</span> <span word="the">the</span> <span word="hypothalamus">hypothalamus</span>, <span word="where">where</span> <span word="they">they</span> <span word="were">were</span> <span word="simply">simply</span> <span word="produced">produced</span> <span word="and">and</span> <span word="then">then</span> <span word="released">released</span> <span word="into">into</span> <span word="the">the</span> <span word="bloodstream">bloodstream</span>.</p><p> <span word="But">But</span> <span word="these">these</span> <span word="beliefs">beliefs</span> <span word="about">about</span> <span word="peptide">peptide</span> <span word="hormones">hormones</span> <span word="were">were</span> <span word="questioned">questioned</span> <span word="as">as</span> <span word="laboratory">laboratory</span> <span word="after">after</span> <span word="laboratory">laboratory</span> <span word="found">found</span> <span word="that">that</span> <span word="antiserums">antiserums</span> <span word="to">to</span> <span word="peptide">peptide</span> <span word="hormones">hormones</span>, <span word="when">when</span> <span word="injected">injected</span> <span word="into">into</span> <span word="the">the</span> <span word="brain">brain</span>, <span word="bind">bind</span> <span word="in">in</span> <span word="places">places</span> <span word="other">other</span> <span word="than">than</span> <span word="the">the</span> <span word="hypothalamus">hypothalamus</span>, <span word="indicating">indicating</span> <span word="that">that</span> <span word="either">either</span> <span word="the">the</span> <span word="hormones">hormones</span> <span word="or">or</span> <span word="substances">substances</span> <span word="that">that</span> <span word="cross">cross</span>-<span word="react">react</span> <span word="with">with</span> <span word="the">the</span> <span word="antiserums">antiserums</span> <span word="are">are</span> <span word="present">present</span>. <span word="The">The</span> <span word="immunological">immunological</span> <span word="method">method</span> <span word="of">of</span> <span word="detecting">detecting</span> <span word="peptide">peptide</span> <span word="hormones">hormones</span> <span word="by">by</span> <span word="means">means</span> <span word="of">of</span> <span word="antiserums">antiserums</span>, <span word="however">however</span>, <span word="is">is</span> <span word="imprecise">imprecise</span>. <span word="Cross">Cross</span>-<span word="reactions">reactions</span> <span word="are">are</span> <span word="possible">possible</span> <span word="and">and</span> <span word="this">this</span> <span word="method">method</span> <span word="cannot">cannot</span> <span word="determine">determine</span> <span word="whether">whether</span> <span word="the">the</span> <span word="substances">substances</span> <span word="detected">detected</span> <span word="by">by</span> <span word="the">the</span> <span word="antiserums">antiserums</span> <span word="really">really</span> <span word="are">are</span> <span word="the">the</span> <span word="hormones">hormones</span>, <span word="or">or</span> <span word="merely">merely</span> <span word="close">close</span> <span word="relatives">relatives</span>. <span word="Furthermore">Furthermore</span>, <span word="this">this</span> <span word="method">method</span> <span word="cannot">cannot</span> <span word="be">be</span> <span word="used">used</span> <span word="to">to</span> <span word="determine">determine</span> <span word="the">the</span> <span word="location">location</span> <span word="in">in</span> <span word="the">the</span> <span word="body">body</span> <span word="where">where</span> <span word="the">the</span> <span word="detected">detected</span> <span word="substances">substances</span> <span word="are">are</span> <span word="actually">actually</span> <span word="produced">produced</span>.</p><p> <span word="New">New</span> <span word="techniques">techniques</span> <span word="of">of</span> <span word="molecular">molecular</span> <span word="biology">biology</span>, <span word="however">however</span>, <span word="provide">provide</span> <span word="a">a</span> <span word="way">way</span> <span word="to">to</span> <span word="answer">answer</span> <span word="these">these</span> <span word="questions">questions</span>. <span word="It">It</span> <span word="is">is</span> <span word="possible">possible</span> <span word="to">to</span> <span word="make">make</span> <span word="specific">specific</span> <span word="complementary">complementary</span> <span word="DNAs">DNAs</span> <span word="that">that</span> <span word="can">can</span> <span word="serve">serve</span> <span word="as">as</span> <span word="molecular">molecular</span> <span word="probes">probes</span> <span word="seek">seek</span> <span word="out">out</span> <span word="the">the</span> <span word="messenger">messenger</span> <span word="RNAs">RNAs</span> <span word="of">of</span> <span word="the">the</span> <span word="peptide">peptide</span> <span word="hormones">hormones</span>. <span word="If">If</span> <span word="brain">brain</span> <span word="cells">cells</span> <span word="are">are</span> <span word="making">making</span> <span word="the">the</span> <span word="hormones">hormones</span>, <span word="the">the</span> <span word="cells">cells</span> <span word="will">will</span> <span word="contain">contain</span> <span word="these">these</span> <span word="mRNAs">mRNAs</span>. <span word="If">If</span> <span word="the">the</span> <span word="products">products</span> <span word="the">the</span> <span word="brain">brain</span> <span word="cells">cells</span> <span word="make">make</span> <span word="resemble">resemble</span> <span word="the">the</span> <span word="hormones">hormones</span> <span word="but">but</span> <span word="are">are</span> <span word="not">not</span> <span word="identical">identical</span> <span word="to">to</span> <span word="them">them</span>, <span word="then">then</span> <span word="the">the</span> <span word="c">c</span> <span word="DNAs">DNAs</span> <span word="should">should</span> <span word="still">still</span> <span word="bind">bind</span> <span word="to">to</span> <span word="these">these</span> <span word="mRNAs">mRNAs</span>, <span word="but">but</span> <span word="should">should</span> <span word="not">not</span> <span word="bind">bind</span> <span word="as">as</span> <span word="tightly">tightly</span> <span word="as">as</span> <span word="they">they</span> <span word="would">would</span> <span word="to">to</span> <span word="m">m</span> <span word="RNAs">RNAs</span> <span word="for">for</span> <span word="the">the</span> <span word="true">true</span> <span word="hormones">hormones</span>. <span word="The">The</span> <span word="cells">cells</span> <span word="containing">containing</span> <span word="these">these</span> <span word="mRNAs">mRNAs</span> <span word="can">can</span> <span word="then">then</span> <span word="be">be</span> <span word="isolated">isolated</span> <span word="and">and</span> <span word="their">their</span> <span word="mRNAs">mRNAs</span> <span word="decoded">decoded</span> <span word="to">to</span> <span word="determine">determine</span> <span word="just">just</span> <span word="what">what</span> <span word="their">their</span> <span word="protein">protein</span> <span word="products">products</span> <span word="are">are</span> <span word="and">and</span> <span word="how">how</span> <span word="closely">closely</span> <span word="the">the</span> <span word="products">products</span> <span word="resemble">resemble</span> <span word="the">the</span> <span word="true">true</span> <span word="peptide">peptide</span> <span word="hormones">hormones</span>.</p>
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