简介：AbstractSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused many deaths and contributed to a tremendous public health concern worldwide since 2020. Angiotensin-converting enzyme 2 (ACE2) binds to the SARS-CoV-2 virus as a receptor. The challenge of different nonhuman primate (NHP) species by SARS-CoV-2 virus demonstrated different effects on virus replication and disease pathology. This study characterizes differences between host ACE2 sequences of three NHP species: Macaca mulatta, Macaca fascicularis, and Chlorocebus sabaeus. In addition, the binding affinity between the ACE2 ectodomain and the SARS-CoV-2 S receptor-binding domain (RBD) was analyzed. Variation of ACE2 sequence among NHP species and the binding affinity may account for different susceptibility and responses to SARS-CoV-2 infection.

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简介：Thispaperproposesanewtectonicpatternofthedeep-seatedstructuresinChinaanditsadjacentareas(includingtheT-A-BsystemoftheRyukyuIslands).Thisisbasedonstudiesofthegravityfieldandgravityinversioncoupledwiththesummationofthemostrecentachievementsingeophysicalstudies.Fromaplate-tectonicpointofview,themetallogeniccharacteristicsandtheirindicationsatdepth,aswellasrelevantgeophysical-geologicalcharacteristicsoffourtectonicenvironmentsoftheChinesecontinentareanalysed,andaclassificationofcompositemetallogenicprovincesandbeltsandpredictionofmetallogenicprospectsaremade.TheauthorextendstheKunlun-Qilian-QinlingtectonicbelttotheT-A-BsystemoftheRyukyuIslandsthroughtheNWdeepboundaryoftheHangzhouBay,andalsoproposesthefollowingbasicviews’themigrationandsuperpositionoftectonicenvironmentsledtotheformationofacompositemetallogenicsystem;thechangeinthetectonicenvironmentresulted

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简介：目的建立以分子生物学技术为基础的华支睾吸虫与扇棘单睾吸虫的ITS-2序列分析鉴别方法。方法在华支睾吸虫流行区采集华支睾吸虫和扇棘单睾吸虫成虫，从成虫虫体分离并收集虫卵。以蛔虫、鞭虫、钩虫、蛲虫做对照虫种，按不同虫种和虫卵数分成5个实验组，各组分别提取DNA，并扩增ITS-2序列，对扩增产物进行测序并作同源性分析以确保为目标片段，根据PCR扩增产物电泳获得的条带判定虫种。结果以华支睾吸虫和扇棘单睾吸虫虫卵DNA为模板的PCR产物电泳图谱分别在400bp、500bp左右各显示一条明显条带；在以两种虫卵DNA混合液为模板的PCR产物中，电泳图谱在400bp左右和500bp左右各显示明显条带。将测序得到的两种核苷酸序列进行Blast比对后，显示与GenBank中相应的华支睾吸虫和扇棘单睾吸虫序列高度同源。混入四种肠道线虫虫卵DNA的PCR产物中，除目的条带外，无其他条带。结论该方法可以对华支睾吸虫及扇棘单睾吸虫虫卵进行鉴别，且结果不受常见四种肠道线虫虫卵干扰，敏感性和特异性较高，可作为两虫种的鉴别检测方法。

简介：ThedensitiesofCO_2inclusionsinmineralsarecommonlyusedtodeterminethecrystallizingconditionsofthehostminerals.However,conventionalmicrothermometryisdifficulttoapplyforinclusionsofsmallsize(<5-10μm)orlowdensity.RamananalysisisanalternativemethodfordeterminingCO_2density,providedthattheCO_2density-Ramanshiftrelationisknown.ThisstudyaimstoestablishthisCO_2density-RamanshiftrelationbyusingCO_2inclusionssynthesizedinfusedsilicacapillaries.Byusingthisnewly-developedsynthetictechnique,weformedpureCO_2inclusions,andtheirdensitiesweredeterminedbymicrothermometry.TheRamananalysisshowedthattherelationbetweenCO_2density(Ding/cm3)andtheseparations(△incm~(-1))betweenthetwomainbands(i.e.Fermidiadbands)inCO_2Ramanspectracanberepresentedbyacubicequation:D(g/cm~3)=0.74203(-0.019⊿~3+5.90332⊿~2-610.79472⊿+21050.30165)-3.54278(r~2=0.99920).OurcalculatedDvalueforagiven⊿isbetweenthoseobtainedfromtwopreviously-reportedequations,whichwerederivedfromdifferentexperimentalmethods.AnexamplewasgiveninthisstudytodemonstratethatthedensitiesofnaturalCO_2inclusionsthatcouldnotbederivedfrommicrothermometrycouldbedeterminedbyusingourmethod.

简介：Thepurposeofthestudyistoestablishafluorescencequantitativereversetranscriptionpoly-merasechainresponse(FQ-RT-PCR)methodforthequantitativedeterminationofIL-2mRNAandIL-4mRNAinThcells,withwhichtheThcellsstatusofthepatientswithgynaecologicaltumorsandchronicrenalfailure(CRF)canbeanalyzed.IL-2cDNAandIL-4cDNAwereprepared,andtheplasmidpMD18carryingIL-2cDNAorIL-4cDNAfragmentwasconstructedandclonedasthetemplateforquantitativedetermination.Theprimersandprobeslabelledwith6-carboxy-fluorescein(FAM)and6-carboxy-tetrarnethylrhodamine(TAMRA)wereprepared,andtheexperimentalconditionswereoptimizedtosetuptheFQ-RT-PCRmethodforquantitativedeterminationofIL-2mRNAandEL-4mRNA.Thcellsenrichedfromperipheralbloodmononuclearcells(PBMCs)of20healthyvolunteers(HVs),16gynaecologicalbenign(GB)cases,18gynaecologicalmalignant(GM)tumorcasesand16chronicrenalfailure(CRF)patientsweretestedforIL-2mRNAandIL-4mRNAbyFQ-RT-PCR.Thehouse-keepinggeneβ-actinwasusedastheinternalcontrolgeneoftheexperiment.Thestandardcurveforlogconcentrationofseriesofquantitativetemplatesvsthresholdcycle(CT)wasestablishedbylinearregression,andthelinearrangewas102-107copies/μl.TheimprecisiontestshowedtheCVofinter-assayandintra-assayofahighcontentsamplebyFQ-RT-PCRwere7.8%and12.5%,respectively.TheCVofinter-assayandintra-assayofalowcontentsamplewere10.8%and19.5%,respectively.TheIL-2mRNAexpressionsinThofthepatientswithgynaecologicalmalignanttumor(comparedwiththeHVsandthepatientswithgynaecologicalbenigndisease)andinThoftheCRFpatients(comparedwiththeHVs)weredeclinedsignificantlyandatthesametimetheIL-4mRNAexpressionincreasedsignificantly(P<0.001).Asimple,sensitiveandaccurateFQ-RT-PCRmethodforthequantitativedetectionofIL-2mRNAandIL-4mRNAhasbeenestablished.TheIL-2mRNAandIL-4m

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简介：Jane想通过互联网买台手提电脑，体验一下网上购物，看来一切只需轻点鼠标便可轻松完成。

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简介：TheIraqwarandanti-terrorismbecamemajortopicsduringthisyear'spresidentialcampaignintheUnitedStates.Heateddebatesoverthetwoissuesaswellaslong-termandunusuallyfixed"stricthalf-and-half"divisionofU.S.mediaandsocietyalsocausedbythetwoissues,toagreatextent,havedeeplyrevealedthechangesofAmerica'spowerstatusinworldpolitics.

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