英语论文文献综述(描述研究现状).pdfVIP

Generaldescriptionsoftherelevantliterature：

AconsiderableamountofliteraturehasbeenpublishedonX。Thesestudies。。。。

Thereisalargevolumeofpublishedstudiesdescribingtheroleof...。

ThefirstseriousdiscussionsandanalysesofXemergedduringthe1970swith.。。。

Thegeneralisabilityofmuchpublishedresearchonthisissueisproblematic.

WhatweknowaboutXislargelybaseduponempiricalstudiesthatinvestigate

how.。。.

Duringthepast30yearsmuchmoreinformationhasbecomeavailableon。...

Inrecentyears,therehasbeenanincreasingamountofliteratureon.。..

Alargeandgrowingbodyofliteraturehasinvestigated.。。.

Generalreferencetopreviousresearch/scholarlyactivity（usuallymorethan

oneauthor)

Manyhistorianshavearguedthat.。。.(eg。Jones,1987;Johnson，1990；Smith，

1994）

Numerousstudieshaveattemptedtoexplain。..。（forexample,Smith，1996;

Kelly,1998;Johnson,2002）

Recentevidencesuggeststhat。。.。(Smith,1996;Jones1999；Johnson,2001)

Recently,invitrostudieshaveshownthatT。thermophylusEFTucan.。。.（Patelet

al.，1997;Jonesetal。，1998）.

SurveyssuchasthatconductedbySmith(1988）haveshownthat。.。。

Severalattemptshavebeenmadeto.。.。（Smith,1996;Jones1999;Johnson，2001)

SeveralstudieshaverevealedthatitisnotjustXthatactson。（Smith，1996;

Jones。.。。

SeveralbiographiesofHarrishavebeenpublished。Smithpresentsan。..。account,

whilstJones

SeveralstudiesinvestigatingXhavebeencarriedouton.。。.

Datafromseveralsourceshaveidentifiedtheincreasedmorbidityandmortality

associatedwithobesity

Previousstudieshavereported.。..(Smith，1985；Jones，1987;Johnson,1992）。

PreviousresearchfindingsintoXhavebeeninconsistentandcontradictory（Smith,

1996；Jones1999,.。.。

Anumberofstudieshavefoundthat...。（Smith，2003;Jon