简介：AbstractBackground:Extra-corporeal video telescope operating monitor system provides a necessary instrument to perform high-precision neurosurgical procedures that could substitute or supplement the traditional surgical microscope. The present study was designed to evaluate a compact high-definition two-dimensional exoscope system for assisting in surgical removal of large vestibular schwannoma (VS), as an alternative to a binocular surgical microscope.Methods:Patients with Koos grade 3 and grade 4 VS undergoing surgery were enrolled in this prospective cohort study between January 2013 and June 2018. The demographics and tumor characteristics (size, Koos grade, composition [cystic or solid mass]) were matched between the two groups of patients. The following outcome measurements were compared between the two groups: duration of surgery, volume of blood loss, extent of tumor resection, number of operating field adjustments, pre- and post-operative facial and cochlear nerve function evaluated at 3 months post-surgery, complications and surgeons’ comfortability.Results:A total of 81 patients received tumor resection through the retrosigmoid approach under either an exoscope (cases, n = 39) or a surgical microscope (control, n = 42). Patients in the two groups had comparable tumor location (P = 0.439), Koos grading (P = 0.867), and composition (P = 0.891). While no significant differences in the duration of surgery (P = 0.172), extent of tumor resection (P = 0.858), facial function (P = 0.838), and hearing ability (P = 1.000), patients operated on under an exoscope had less blood loss (P = 0.036) and a fewer field adjustments (P < 0.001). Both primary and assistant surgeons reported a high level of comfort operating under the exoscope (P = 0.001 and P < 0.001, respectively).Conclusions:The compact high-definition two-dimensional exoscope system provides a safe and efficient means to assist in removing large VSs, as compared to a surgical microscope. After the acquaintance with a visual perception through a dynamic hint and stereoscopically viewing corresponding to the motion parallax, the exoscope system provided a comfortable, high-resolution visualization without compromising operational efficiency and patient safety.

简介：

简介：Thepresentstudywasdesignedtodevelopandvalidateasensitiveandreliableultrahighperformanceliquidchromatographycoupledwithquadrupoletime-of-flightmassspectrometry(UPLC-QTOF/MS)methodtoseparateandidentifythechemicalconstituentsofQixueShuangbuTincture(QXSBT),aclassictraditionalChinesemedicine(TCM)prescription.UndertheoptimizedUPLCandQTOF/MSconditions,56componentsinQXSBT,includingchalcones,triterpenoids,protopanaxatriol,flavonesandflavanoneswereidentifiedandtentativelycharacterizedwithinarunningtimeof42min.Thecomponentswereidentifiedbycomparingtheretentiontimes,accuratemass,andmassspectrometricfragmentationcharacteristicions,andmatchingempiricalmolecularformulawiththatofthepublishedcompounds.Inconclusion,theestablishedUPLC-QTOF/MSmethodwasreliableforarapididentificationofcomplicatedcomponentsintheTCMprescriptions.

简介：Duringthelasttwodecadesfractionalcalculushasbeenincreasinglyappliedtophysics,especiallytorheology.ItiswellknownthatthereareobiviousdifferencesbetweenRiemann-Liouville(R-L)definitionandCaputodefinition,whicharethetwomostcommonlyuseddefinitionsoffractionalderivatives.Themultipledefinitionsoffractionalderivativeshavehinderedtheapplicationoffractionalcalculusinrheology.Inthispaper,weclarifythattheR-LdefinitionandCaputodefinitionarebothTheolog...

简介：

简介：ＡＮＯＶＥＬＤＥＦＩＮＩＴＩＯＮＯＦＦＯＲＭＦＥＡＴＵＲＥＧａｏＦｅｉ；ＹｅＳｈａｎｇｈｕｉＡＮＯＶＥＬＤＥＦＩＮＩＴＩＯＮＯＦＦＯＲＭＦＥＡＴＵＲＥ￥ＧａｏＦｅｉ；ＹｅＳｈａｎｇｈｕｉＡｂｓｔｒａｃｔＢｅｉｎｇａｎｅｓｓｅｎｔｉａｌｃｏｎｃｅｐｔｉ...

简介：Thelongcontroversyovertheterm‘Quaternary'asachronostratigraphicunitmaybereachinganapotheosis,judgingfromrecentpapers(PillansandNaish,2004;Gibbardetal.,2005;andreferencestherein).Thedebateisnolongercenteredonwhetherthereshouldbeaplaceinthegeologicaltimescaleforaunittermed‘Quaternary'-despiteitsdubiouspast,itcannotbedeniedthatalargebodyofearth-historicalresearchisstronglyidentifiedwiththisterm.ThechallengenowconcernsanappropriaterankanddefinitionofQuaternarywithregardtootherchronostratigraphicunits.Severaloptionshavebeenproposed(PillansandNaish,2004),andGibbardetal.(2005)encourageadebateonthesebeforedecisionisreached.Inthisbriefnote,wedescribeanarrangementnotpreviouslyconsideredthatseemsadvantageous.Itisinstructive,however,tofirstreviewthePleistoceneSeriesandNeogeneSystem,thetwounitsthataredirectlyaffectedbyintroductionoftheQuaternaryintothechronostratigraphichierarchy.

简介：特征技术在设计和制造中的成功应用取决于其形式化理论的建立．本文从形式化定义和可制造性分析两个方面研究了面向制造设计中制造特征的形式化描述方法，提出了基于设计几何材料去除操作选择和规划的相关制造特征定义，给出了相应的可制造性分析算法框架．所提出的方法为基于特征的ＣＡＤ／ＣＡＭ集成，尤其是为设计自动化的实现提供了一种新的思路．

简介：破坏损害被定义为avery骨头和软纸巾的严重损坏。我们在一些破裂盒子中发现了那的Butin临床的实践，软纸巾的损坏不象“destructiveinjury”一样严重显示，而弄碎破裂stillcannot表演骨头损坏的严厉。因此我们proposeda新术语“destructivefractures”在把破坏损害的定义与典型诊所盒子相结合以后。破坏破裂指谁的破裂骨状的纸巾太严重被损坏被修理，但是软纸巾，神经和静脉是严重地伤害的更少，canbe修理。从一年2001～2010，破坏破裂的75个盒子被同意进入我们的部门。根据是否与外部环境连结的破裂和破裂地点，他们被划分成6种类型：al类型，关上的骨干破坏骨折；a2类型，开的骨干破坏骨折；bl类型，关上的包含关节的破坏骨折；b2类型，开的包含关节的destructivefracture；c1类型，关上的混合破坏骨折；c2类型，开的混合破坏骨折。相应临床的治疗为破坏骨折的新分类标准是的每type.The被进行简单、实际并且thuscan被用作一个重要指南为破坏破裂做合理treatmentplans。

简介：

简介：

简介：Likevaluechainandsupplychain,“industrialchain”becomesthefocusofattention.Theimplicationof“industrialchain”hasgainedalargerangeofextension.Itnotonlyexpressestheindustrial“chain”structureandrelationshipof“backandforward”inorderor“upanddown”indirection,butalsoitrepresentsaclusteroflargescaleoffirmsinanareaorcolony.Itisanetwork,oracommunity.Consequently,weconcludethat“industrialchain”isasynthesisofindustrialchain,industrialcluster,orindustrialnetwork.Inthisarticle,firstlywewilldistinguishindustrychainfromindustry.Anindustryisthecollectionoffirmsthathavethesameattribute,soanindustrycanbedefinedbyfirmcollectionofcertainattribute.Weindicatethatindustrialchainisakindofverticalandorderlyindustriallink.Itisdefinedaccordingtoaseriesofspecificproductorservicecreated.Secondlyweanalyzetheverticalorderlydefiinitionprocessfromtheaspectsofsocialdivisionoflaborandrequirementdivision,self-organizationsystem,andvalueanalysis.Non-symmetryanddependingonsystemorcommunityoflargescaleofindustrialunitsleadtoentireindustryto“orderly”structure.Ontheotherhand,thedraughtofdiversityandcomplexityofrequirementsimultaneouslyleadtoentireindustrytobemore“orderly”.Alongwithprocessesofself-organization,industrialwillappi'oachthestateofmoreorderlyandsteady,andconstantlymakeindustrialchainupgrade.Eachfirmorunit,whowillgainthevalue,hastoestablishchannelsofvalue,whichwecalled“industrialvaluechain”.Lastly,wediscusstheconsequenceofverticalandorderlydefinition,whichisexhibitedbyacertainrelationshipbody.Thetypicalformsofindustrialchainincludeindustrialcluster,strategyallianceandverticalintegrationetc.

简介：InEgyptologydealingwithbothhistoricalandliterarytextsoftenraisesthequestionoftheirpoliticalintention.Thealmostfixedplotofthe"Knigsnovelle”andthe“annals,"typicalformsofrecordingEgyptianhistory,seemstoreflecttherigidEgyptianviewofhistoryanchoredinideology.Thehistoricalcourseofevents,whatwemaycall“reality,”islesssignificantthanthecoursepostulated

简介：

简介：特征定义的适应性是特征技术在设计过程成功应用的关键和核心问题．本文基于提出了面向设计过程的特征定义层次结构及特征定义方法，将特征定义用应用特征、形状特征和几何表示３个相对独立的层次来表示，并分别利用特征语义解释器和改进的几何关联图实现层次间的有效连接和相互转换，这不仅消弱了特征定义对应用的依赖性而更具广泛性，也为基于特征的并行设计过程模型的建立提供了基础．

简介：

简介：

简介：

简介：

简介：极具创造性的SOMATOMDefinition，世界首台双源CT一种与您以往见过的完全不同的CT，一种将永远改变您对CT认识的CT，一种将在CT世界掀起一场革命的CT。她的问世再一次显示出了西门子在CT技术创新和临床应用创新的领导者地位。