HB 4202-1989 单头带圆锥尾量头用手柄 (D=2.5~21mm)
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来源:标准资料网
基本信息
标准名称: | 单头带圆锥尾量头用手柄 (D=2.5~21mm) |
中标分类: |
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发布日期: | 1989-05-13 |
实施日期: | 1989-12-01 |
首发日期: | 1900-01-01 |
作废日期: | 1900-01-01 |
出版日期: | 1900-01-01 |
页数: | 1页 |
适用范围
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前言
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目录
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引用标准
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所属分类:
【英文标准名称】:StandardSpecificationforHeadedSteelBarsforConcreteReinforcement
【原文标准名称】:钢筋混凝土用有头钢棒的标准规范
【标准号】:ASTMA970/A970M-2007
【标准状态】:现行
【国别】:美国
【发布日期】:2007
【实施或试行日期】:
【发布单位】:美国材料与试验协会(ASTM)
【起草单位】:ASTM
【标准类型】:()
【标准水平】:()
【中文主题词】:棒材;混凝土;低合金钢;加筋;加强棒材;钢;结构钢;焊接的
【英文主题词】:Bars;Concrete;Concretes;Low-alloysteels;Reinforcement;Reinforcingbars;Steels;Structuralsteels;Welded
【摘要】:
【中国标准分类号】:H44
【国际标准分类号】:77_140_15
【页数】:6P;A4
【正文语种】:英语
【英文标准名称】:StandardGuideforPerformanceoftheChineseHamsterOvaryCell/HypoxanthineGuaninePhosphoribosylTransferaseGeneMutationAssay
【原文标准名称】:中国仓鼠卵巢细胞/次黄质鸟嘌呤转磷酸核糖基酶基因变异鉴定的操作
【标准号】:ASTME1262-1988(2003)
【标准状态】:现行
【国别】:
【发布日期】:1988
【实施或试行日期】:
【发布单位】:美国材料与试验协会(ASTM)
【起草单位】:F04.16
【标准类型】:(Guide)
【标准水平】:()
【中文主题词】:分析;遗传工程;说明书;生物化学
【英文主题词】:biological;bioassay;cell;scientific;
【摘要】:TheCHO/HGPRTassaydetectsforwardmutationsoftheX-linkedhypoxanthine-guaninephosphoribosyltransferase(hgprt)locus(codingfortheenzyme,HGPRT)inChinesehamsterovary(CHO)cells.CellsoriginallyderivedfromChinesehamsterovarytissueareexposedtoatestarticleand,followinganappropriatecellcultureregimen,descendantsoftheoriginaltreatedpopulationaremonitoredforthelossoffunctionalHGPRT,presumablyduetomutations.Resistancetoapurineanalogue,6-thioguanine(6TG)(orlessdesirably,8-azaguanine(8AG)),isemployedasthegeneticmarker.HGPRTcatalyzestheconversionofthenontoxic6TGtoitstoxicribophosphorylatedderivative.Lossoftheenzymeoritsactivitythereforeleadstocellsresistantto6TG.BecauseHGPRTisanenzymeofthepurinenucleotidesalvagepathway,lossoftheenzymeisnotalethalevent.Differenttypesofmutationalevents(basesubstitutions,frameshifts,deletions,somechromosomaltypelesions,andsoforth)shouldtheoreticallybedetectableatthehgprtlocus.TheCHO/HGPRTassayhasbeenusedtostudyawiderangeofmutagens,includingradiations(2-4),andawidevarietyofchemicals(1),andcomplexchemicalmixtures(5).1.1Thisguidehighlightssomeofthemorerelevantbiologicalconceptsastheyarecurrentlyunderstood,andsummarizesthecriticaltechnicalaspectsforacceptablebioassayperformancesastheycurrentlyareperceivedandpracticed.TheChinesehamsterovarycell/hypoxanthineguaninephosphoribosyltransferase(CHO/HGPRT)assay()hasbeenwidelyappliedtothetoxicologicalevaluationofindustrialandenvironmentalchemicals.1.2Thisguideconcentratesonthepracticalaspectsofcellculture,mutagenesisprocedures,dataanalysis,qualitycontrol,andtestingstrategy.Thesuggestedapproachrepresentsaconsensusofthepanelmembersfortheperformanceoftheassay.Itistobeunderstood,however,thatthesearemerelygeneralguidelinesandarenottobefollowedwithouttheuseofsoundscientificjudgement.Usersoftheassayshouldevaluatetheirapproachbasedonthepropertiesofthesubstancestobetestedandthequestionstobeanswered.1.3Deviationfromtheguidelinesbasedonsoundscientificjudgementshouldbynomeansinvalidatetheresultsobtained.1.4Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafetyandhealthpracticesanddeterminetheapplicabilityofregulatorylimitationspriortouse.
【中国标准分类号】:B41
【国际标准分类号】:07_080
【页数】:5P.;A4
【正文语种】: