简介：AbstractBackground:Since the diagnostic value of aldosterone to renin ratio (ARR) calculated by plasma renin concentration (PRC) or plasma renin activity (PRA) is still inconclusive, we conducted a meta-analysis by systematically reviewing relevant literature to explore the difference in the diagnostic efficacy of ARR calculated by PRC or PRA, so as to provide guidance for clinical diagnosis.Methods:We searched PubMed, Embase, and Cochrane Library from the establishment of the database to March 2021. We included studies that report the true positive, false positive, true negative, and false negative values for the diagnosis of primary aldosteronism, and we excluded duplicate publications, research without full text, incomplete information, or inability to conduct data extraction, animal experiments, reviews, and systematic reviews. STATA 15.1 was used to analyze the data.Results:The pooled results showed that ARR (plasma aldosterone concentration [PAC]/PRC) had a sensitivity of 0.82 (95% confidence interval [CI]: 0.78-0.86), a specificity of 0.94 (95% CI: 0.92-0.95), a positive-likelihood ratio (LR) of 12.77 (95% CI: 7.04-23.73), a negative LR of 0.11 (95% CI: 0.07-0.17), and symmetric area under the curve (SAUC) of 0.982, respectively. Furthermore, the diagnostic odds ratio (DOR) of ARR (PAC/PRC) was 180.21. Additionally, the pooled results showed that ARR (PAC/PRA) had a sensitivity of 0.91 (95% CI: 0.86-0.95), a specificity of 0.91 (95% CI: 0.90-0.93), a positive LR of 7.30 (95% CI: 2.99-17.99), a negative LR of 0.10 (95% CI: 0.04-0.26), and SAUC of 0.976, respectively. The DOR of ARR (PAC/PRA) was 155.52. Additionally, we conducted a subgroup analysis for the different thresholds (<35 or ≥35) of PAC/PRC. The results showed that the DOR of the cut-off ≥35 groups was higher than the cut-off <35 groups (DOR = 340.15, 95% CI: 38.32-3019.66; DOR= 116.40, 95% CI = 23.28-581.92).Conclusions:The research results suggest that the determination of ARR (PAC/PRC) and ARR (PAC/PRA) was all effective screening tools for PA. The diagnostic accuracy and diagnostic value of ARR (PAC/PRC) are higher than ARR (PAC/PRA). In addition, within a certain range, the higher the threshold, the better the diagnostic value.

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简介：Agreenprocessfortheoxygen-freeconversionofmethanetohigh-concentrationethyleneandhydrogeninaplasina-followed-by-catalyst(PFC)reactorispresented.Withoutanycatalystsandwithpuremethaneusedasthefeedgas,astablekilohertzsparkdischargeleadstoanacetyleneyieldof64.1%,ethyleneyieldof2.5%andhydrogenyieldof59.0%with80.0%ofmethaneconversionatamethaneflowrateof50cm~3/minandaspecificinputenergyof38.4kJ/L.Intheeffluentgasfromastablekilohertzsparkdischargereactor,theconcentrationsofacetylene,ethyleneandhydrogenwere18.1%,0.7%and66.9%,respectively.WhencatalystsPd-Ag/Si02wereemployedinthesecondstagewithdischargeconditionssameasinthecaseofplasmaalone,thePFCreactorprovidesanethyleneyieldof52.1%andhydrogenyieldof43.4%.TheconcentrationsofethyleneandhydrogenintheeffluentgasfromthePFCreactorwerefoundtobeashighas17.1%and62.6%,respectively.Moreover,noacetylenewasdetectedintheeffluentgas.Thismeansthatahighconcentrationofethyleneandoxygen-freehydrogencanbeco-produceddirectlyfrommethaneinthePFCreactor.

简介：BackgroundTotheeffectofpercutaneouscoronaryintervention(PCI)onplasmalevelofN-terminalpro-Btypenatriureticpeptide(NT-proBNP)inpatientswithcoronaryheartdisease(CHD)andnormalleftventricularfunction.MethodsOnehundredandfivepatientswithCHDandnormalventricularfunctionwereenrolled.BloodsamplesforassessmentofNT-proBNPandcTn-TwerecollectedbeforeandafterPCI.ResultsThemeanleftventricularejectionfractionwas60.3±5.3%.Afterrevascularization,theleveloflgNT-proBNPwassignificantlyreduced(2.40±0.44vs2.23±0.43,P<0.001).SubgroupanalysisshowedthattheleveloflgNT-proBNPwasconsistentlydecreasedindifferentclinicalclassifications(stableangina45,unstableangina31andacutemyocardialinfarction29)andtarget-vesselrevascularization(leftanteriordescendingartery30,leftcircumflexartery26andrightcoronaryartery49),andin99patientswithoutelevationofpost-proceduralcTnT,butitshowedatrendofnon-significantincreasein6patientswithelevatedcTn-T.ConclusionsOurstudydemonstratesthatsuccessfulPCIreducesplasmaNT-proBNPconcentrationinpatientswithCHDandnormalventricularfunction.ThisimplicatesthattheimpactofPCIshouldbeconsideredintheinterpretationofNT-proBNPchangeinclinicalpractice,andfurtherstudiesarenecessarytoinvestigatethedirectand/orindirecteffectofmyocardialischemiaonBNP/NT-proBNP.

简介：Theexpressionandfunctioningrowthandapoptosisoftherenin-angiotensinsystem(RAS)wasevaluatedinhumanglioblastoma.Reninandangiotensinogen(AGT)mRNAsandproteinswerefoundbyinsituhybridisationandimmunohistochemistryinglioblastomacells.Angiotensinogenwaspresentinglioblastomacysticfluids.Thus,humanglioblastomacellsproducereninandAGTandsecreteAGT.Humanglioblastomaandglioblastomacellsexpressedrenin,AGT,reninreceptor,AT(2)and/orAT(1)mRNAsandproteinsdeterminedbyRT-PCRand/

简介：Debrisflowsinnaturegenerallyfallintothreegroupsdistinctintheirgraincomposition:water-stoneflow,orsub-viscousdebrisflow,dominatedbycoarsegrains;muddyflow,dominatedbyfinegrains;andviscousdebrisflowcomposedofgrainsinlargerange.Liquid-phasevelocityandsedimentarydeliveryresistanceofsub-viscousdebrisflowhavebeendiscussedbasedonthecompositioncharactersofsub-andhigh-viscousdebrisflows.Itisrevealedthatthepresenceoffinegrainsplaysavitalroleinaffectingresistanceandaveragevelocity,particularlywhenthevolumefractionofgrainsintheflowisrelativelyhigh,i.e.Sv＞0.45.Grain-sizedistributionofviscousdebrisflowischaracterizedbyabimodalcurve,whichexplainsthepropertieslikehighdensityandlowresistancegradientofdebrisflows.Acalculationformulaisfinallyputforward,whichhastosomeextentovercomelocalitylimitsandachievedagoodagreementwiththefieldobservationsofdebrisflowsinSouthwestChina.

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简介：血浆nitrocarburizing和血浆氧化处理被执行改进wear和SKD61钢的腐蚀抵抗。血浆nitrocarburizing在生产epsilon-Fe2_3的氮，氢和甲烷空气在540°C为12h被进行(N，C)血浆nitrocarburising生产的phase.The混合物层主要由电子阶段组成，与gamma'-Fe4的一个小比例(N，C)复合的层和扩散层的phase.The厚度是大约10亩m和大约200/^m，respectively.Plasma柱子氧化为1h.The在500°C的经常的温度与各种各样的氧/氢比率在nitrocarburized样品上被执行在在复合的层上的厚度的1-2亩m的很薄的磁铁矿(Fe3O4)层被获得。阳极极化测试表明那个血浆nitrocarburizing过程贡献了SKD61钢的腐蚀抵抗的重要改进。然而，nitrocarburized混合物层的腐蚀特征被氧化处理败坏。

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简介：AnonlinearBurgers’modelisusedtodescribeverticalinfiltrationofwaterintoanon--swellingsoilwithprescribedconcentrationconditionsattheboundary.Theexactsolutionisconstructedintermsofaseriesinvolvingcomplementaryerrorintegrals.

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简介：Insteady,solid-liquidtwo-phaseturbulentflows,thereexisttwotypicalpatternsoftheverticaldistributionofparticleconcentration.ThepatternIshowsamaximumconcentrationatanelevationabovethebed.ThepatternIIshowsanincreaseoftheparticleconcentrationdownwardoverthewholevertical,withthemaximumatthebed.MostofthetheoriesonparticleconcentrationdistributionhavebeendonewiththepatternII,anditislackofasuccessfultheorycovetingbothofthetwopatterns.Thispaperreviewstheparticledistributiontheories,includingthediffusiontheory,themixturetheory,theenergytheory,thesimilaritytheory,thestochastictheoryandthekinetictheory.Thekinetictheoryisalsoappliedtodescribetheverticaldistributionofparticleconcentrationinbothdiluteanddenseflows.