某女，31岁，葡萄胎第二次清宫术后2个月，阴道不规则流血持续存在，尿HCG(+)。B超显示：子宫肌层可见高回声团，边界清但无包膜。组织学可见绒毛退化痕迹。应首先考虑是（）
B
侵蚀性葡萄胎和绒毛膜癌患者在临床表现基本相同：葡萄胎清除后出现不规则阴道流血，血、尿HCG测定持续高水平或一度下降后又上升，子宫正常大或不同程度增大，肌层内可见高回声团，边界清但无包膜。区别为，见到绒毛结构或绒毛退变痕迹，即可诊断为侵蚀性葡萄胎;若仅见大量的滋养细胞浸润和坏死出血，未见绒毛结构者，诊断为绒癌;若原发灶和转移灶诊断不一致，只要在任一组织切片中见到绒毛结构即可诊断为侵蚀性葡萄胎。
PartIVTranslation
Bymakingvehicleslighterinweightaluminumhasgreatlyreducedtheamountoffuelneededtomovethem,(PassageTwo)
Wecanconcludefromthepassagethat________.
Passage2
Questions6to10arebasedonthefollowingpassage:
Thefoodweeatseemstohaveprofoundeffectsonourhealth.Althoughsciencehasmadeenormousstepsinmakingfoodmorefittoeat,ithas,atthesametime,mademanyfoodsunfittoeat.Someresearchhasshowntat40percentofcancerisrelatedtothedietaswell,especiallycancerofthecolon.Differentculturesatemorepronetogetcertainillnessesbecauseofthefoodthatischaracteristicinthesecultures.Thatfoodisrelatedtoillnessisnotanewdiscovery.In1945,governmentresearchersrealizedthatnitratesandnitrites,commonlyusedtopreservecolorinmeats,andotherfoodadditives,causedcancer.Yetthesecarcinogenicadditivesremaininourfood,anditbecomesmoredifficultallthetimetoknowwhichthingsonthepackaginglabelsofprocessedfoodarehelpfulorharmful.Theadditivesthatweeatarenotallsodirect.Farmersoftengivepenicillintobeefandpoultry,andbecauseofthis,penicillinhasbeenfoundinthemilkoftreatedcows.Sometimessimilardrugsareadministeredtoanimalsnotformedicinalpurposes,butforfinancialreasons.Thefarmersaresimplytryingtofattentheanimalsinordertoobtainahigherpriceonthemarket.AlthoughtheFoodandDrugAdministration(FDA)hastriedrepeatedlytocontroltheseprocedures,thepracticescontinue.
6.Howhassciencedoneadisservicetomankind?
A.Becauseofscience,mostofthefoodsweeattodayarecontaminated.
B.Ithascausedalackofinformationconcerningthevalueoffood.
C.Asaresultofscientificintervention,somepotentiallyharmfulsubstanceshasbeenaddedtoourfood.
D.Thescientistshavepreservedthecolorofmeats,butnotofvegetables.
7.Whatarenitratesusedfor?
A.Theypreservesflavorinpackagedfoods.
B.Theypreservethecolorofmeats.
C.Theyaretheobjectsofresearch.
D.Theycausetheanimalstobecomefatter.
8.TheFDAhastriedrepeatedlytocontrol.
A.theattempttofattentheanimals
B.theattempttocuresickanimals
C.theusingofdrugstoanimals
D.theusingofadditivestopreservethedoloroffood
9.Theword“carcinogenic”meansmostnearlythesameas.
A.trouble-makingB.color-retaining
C.money-savingD.cancer-causing
10.WhichofthefollowingstatementsisNOTtrue?
A.Drugsarealwaysgiventoanimalsformedicalreasons.
B.Someoftheadditivesinourfoodareaddedtothefooditselfandsomearegiventothelivinganimals.
C.Researchershaveknownaboutthepotentialhazardsofthefoodadditivesforoverthirty-fiveyears.
D.Foodmaycausefortypercentofcancerintheworld.