锑元素与先天性心脏病关系的病例对照研究

采用以院为基础的病例对照研究,在福建省妇幼保健院(三级甲等医院)募集新近发生的69例胎儿先天性心脏病病例,以1∶1配对的方法设立对照组,采用电感耦合等离子体质谱仪分析方法,测定病例组和对照组孕妇孕期头发中锑、锌、铜、铁、铅等元素的含量,并问卷调查孕早期危险因素的暴露情况,用SPSS19.0 Cox比例风险模型进行流行病学多因素分析。孕妇发锑含量偏高(相对危险度的比值比(OR)=33.833;95%可信区间(CI):4.060~281.929)、孕期使用不锈钢餐具(OR=8.981,95%CI:1.085~74.327)、居所周围50 m有马路(OR=11.067,95%CI:1.025~119.521)是先天性心脏病的危险因素。孕期锑负荷增加可能是先天性心脏病的原因之一。     

孕早期超声筛查对胎儿先天性心脏病的评估作用

目的：探讨分析孕早期超声筛查对胎儿先天性心脏病的评估作用。方法：选取2020年6月至2023年6月我院接收的行产前检查的500例孕妇作为研究对象,所有孕妇均接受孕早期胎儿超声筛查,并随访了解最终确诊结果（新生儿超声/尸检）,对孕早期超声筛查在胎儿先天性心脏病中的评估作用进行观察分析。结果：孕11-13+6周,显示成功率最高的切面为胎儿四腔心切面,其后依次为左室流出道切面、右室流出道切面、三血管切面;孕13+6周各切面显示成功率较孕11周、孕12周明显更高（P<0.05）。胎儿心脏超声筛查与最终确诊结果相比无明显差异（P>0.05）。超声诊断准确11例,其中法洛四联症比例最高,占比30.77%;其次为右心室发育不良和心内膜垫缺损,占比均为15.38%;诊断准确率为99.40%、灵敏度为84.62%、特异度为99.79%。结论：孕早期超声筛查能早期显示胎儿心脏畸形,诊断准确率、灵敏度、特异度高,对胎儿先天性心脏病的评估价值高。     

连云港市病残儿童资料分析及孕前优生干预其父母再生育效果研究

目的:分析连云港市病残儿童资料,通过孕前优生健康检查干预其近五年病残儿父母再生育,预防病残儿的发生风险。方法:对连云港市2008―2012年经过医学鉴定的病残儿的资料进行分析,比较其五年间数量、地区、性别分布、疾病顺位变化等,发放调查问卷了解其在生育病残儿之前的基本情况;再次怀孕后有无优生指导、超生排畸、唐筛、妊娠结局、分娩方式等调查,分析干预效果。结果:近五年通过医学鉴定符合病残儿童标准的1 046例五年间无明显变化;城区较农村多;男性较女性多;疾病顺位排序先天性心脏病位于第一位。通过干预,收回问卷中先天性心脏病父母再生育72例均为正常儿,其次脑瘫患儿父母再生育35例均为正常儿。结论:病残儿鉴定父母通过孕前优生健康检查,完成整个孕前保健、风险评估到个性化咨询指导一系列干预后再生育均为正常儿,干预效果明显,减少了不良妊娠结局的发生,对预防和降低再次生育病残儿的发生非常重要。     

昌吉州新生儿先天性心脏病超声心动图筛查分析

目的:为保障昌吉州新生儿健康,规范先天性心脏病超声心动图筛查工作。方法:对昌吉州各医院出生的新生儿在住院期间进行体格检查和心脏听诊,对筛查出的可疑先心病患儿应做超声心动图检查或其它检查确认。结果:共调查1600例新生儿,确诊先天性心脏病的11例,先天性心脏病发生率6.87‰,男婴为6例,女婴为5例,男女发病率之比为1.2:1,无显著性差异(P0.05)。筛查出的11例先天性心脏病患儿中房间隔缺损(ASD)3例,室间隔缺损(VSD)4例,动脉导管未闭(PDA)1例,三尖瓣关闭不全2例,肺动脉狭窄1例。结论:为了预防先天性心脏病的发生,应注意母亲妊娠期特别是在妊娠早期保健。     

中孕期正常胎儿心血管系统结构超声测值的研究

建立宁夏地区妊娠中期胎儿心血管系统各解剖结构内径的正常参考值范围,探求其随孕周变化规律。对妊娠中期(22~28周)正常胎儿1 246例行超声心动图检查,测量心房、心室、卵圆孔、主动脉、肺动脉、左/右肺动脉、主动脉弓峡部、降主动脉、动脉导管内径。根据孕周对测量数据进行分组,同时对各组测量数据和孕周进行相关性研究。胎儿心脏各房室及大血管内径随孕周增加而增大,与孕周显著相关(P0.05)。建立宁夏地区妊娠中期胎儿心血管系统结构相关的正常参考值范围,可评价胎儿心血管系统发育情况,为准确识别胎儿先天性心脏病提供重要依据。     

三维超声在胎儿畸形诊断中的价值分析

目的：通过1312例孕妇产前胎儿超声检查结果,研究三维超声在产前胎儿畸形诊断中的应用价值。方法：对2010年1月至2011年12月本院孕期经超声诊断的胎儿畸形87例病例资料进行回顾性分析．比较胎儿畸形在产前三维超声诊断结论与产后检出的数量及结果。结果：87例畸形胎儿中,产前诊断与产后检查完全相符86例,漏诊1例。畸形病例中,以中枢神经系统畸形最为常见。结论：三维超声可在孕期诊察胎儿器官发育情况．在产前预先发现先天性畸形,对临床有重要的诊断价值。     

应用二维超声心动图广泛性筛查胎儿复杂先天性心脏病的临床价值

目的:探讨胎儿复杂先天性心脏病采取二维超声心动图进行筛查的效果。方法:选取984例2017年10月至2018年12月期间门诊或住院的孕17w以上的中晚孕胎儿,采用GE-VolusonE10彩超检查,对检查结果进行观察。结果:本组984例,阳性32例,发生率为3.25%,其中单纯室缺8例,单腔房室4例,心内膜垫缺损5例,法洛氏四联症3例,三尖瓣闭锁1例,大动脉转位3例,左心发育不良3例,主动脉狭窄并室间隔缺损1例,肺动脉狭窄2例,右室流出道及肺动脉闭锁1例,大型室间隔缺损1例。所有病例均经彩超复诊、引产后病理检查或产后彩超检查确认。假阴性2例,其中1例为完全性大血管转位,1例为单纯性轻型先天性心脏病。结论:二维超声心动图对于胎儿先心病的诊断具有较高的临床价值,值得于临床广泛推广。     

胎儿先天性心脏病中彩色多普勒超声诊断的应用分析

目的:分析胎儿先天性心脏病中彩色多普勒超声诊断的应用价值。方法:选择于2017年1月-2019年1月间我院妇产科接收的检查为胎儿先天性心脏病孕妇64例,所有患者均分别予以常规超声、彩色多普勒超声检查诊断,对比两种方法的临床诊断结果。结果:彩色多普勒超声诊断的检出率为93.75%,常规超声为71.88%,彩色多普勒超声的检出率明显更高。结论:临床上使用彩色多普勒超声对胎儿先天性心脏病检查诊断,具有更高的诊断准确性。     

产前超声对孕11-13周+6胎儿肢体畸形的诊断价值分析

目的:观察孕11-13+6周产前超声检查在诊断胎儿肢体畸形的意义。方法:以2015年1月1日-2017年12月31日入院行孕检的2013例孕妇为本次观察对象,所有孕妇给予行规范化超声检查,测胎儿NT厚度,观察胎儿肢体结构、形态等情况,对早期检查异常者并给予引产者行X线检查,对于继续妊娠者追踪妊娠结局,观察中期超声检查结果。结果:孕早期检出7例,误诊1例、漏诊3例,孕中期检出2例,孕11-13+6周检出率为66.6%,9例异常胎儿其中2例NT出现异常,所占比例为22.2%。结论:胎儿肢体畸形在孕11-13+6周行超声检查检出率较高。     

中孕期胎儿系统超声检查切面及临床意义

目的:浅谈中孕期胎儿系统超声检查切面及临床意义。方法:回顾分析自2013年7月到2014年3月期间,在我社区卫生服务中心进行胎儿系统超声检查的80例孕妇的临床资料。采用Siemens X300彩色多普勒超声诊断仪对胎儿的颅脑切面、颜面部切面、心脏切面和脊柱纵切面等进行中孕期胎儿筛查,待孕妇分娩后进行电话回访。结果:80例中孕期胎儿经超声筛查发现7例胎儿有异常,包括2例唇腭裂、1例消化系统畸形、1例膈疝、1例心脏畸形、1例胎儿水肿综合征和1例左下腹肿块,均为单发畸形。产前超声诊断与产后完全相符。结论:中孕期胎儿超声图像比较典型,筛查切面能有效发现异常胎儿,尽早规划治疗方案提高围产期胎儿的生存率,对优生优育有重要意义。     

Insertion of triangulated surfaces into a meccano tetrahedral discretization by means of mesh refinement and optimization procedures

In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

Flow calorimeter for enthalpy increment measurements on condensed gases

A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa.     

From Industry 4.0 to Research 4.0. Development of High Performance Fibers in the Light of Digitization

We associate a variety of innovations with the term ＂Industry 4.0＂. The pioneer of many 4.0 modifications forms the basisfor the trend towards the integrated di...     

Refrigerators Enter a New Era of Health Preservation Frestech initiates the establishment of China's first standard for household sterilization refrigerators

On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.……     

Roman iron and steel: A review

ABSTRACT

The production of ferrous metal increased during the Roman Late Republican period, Principate and Empire. The direct bloomery process was used to extract the metal from its ores using slag-tapping and slag-pit furnaces. The fuel was charcoal and an air blast was introduced by bellows-operated tuyères. Iron formed as a bloom, often as a spongy mass of metal, which contained impurities from the smelting process, including unreacted ore, fuel, slag and fragments from the furnace walls, while the metal was often inhomogeneous with varied carbon contents. Blooms were either smithed directly into bars or ingots or they were broken up, which also allowed the removal of gross impurities and a selection of pieces with similar properties to be made. These could then be forge-welded together and formed into characteristically shaped ingots. Making steel in the furnace seems to have been achieved: it depended on the ore and the furnace and conditions within it. Surface carburization was also carried out. Iron and steel were used extensively in construction and for tools and weapons. Fire welding was often used to add pieces of steel to make the edges of tools and weapons, which could be heat-treated by quenching to harden them.     

Optimum-Simulation von Ernteprozessen

Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.     

A study of centrifugal cast high boron high speed steel

In the present study a high‐boron high speed steel (HSS) roll material was designed. Many expensive alloy elements have been substituted by cheap boron alloy, and high‐boron high speed steel roll has been manufactured by centrifugal casting method. The microstructures, mechanical properties and wear resistance of centrifugal casting high‐boron high speed steel roll have been investigated by optical microscopy (OM), scanning electron microscopy (SEM), and X‐ray diffraction (XRD) analysis, hardness test, impact test and wear test. The results indicated that the solidification microstructures of high‐boron high speed steel roll consisted of M₂(B,C), (W,Mo)₂(B,C), M₃(B,C), M₂₃(B,C)₆ type borocarbides and martensite, a small amount of retained austenite. Borocarbides were continuously distributed over the grain boundary. After quenching from 1050 °C, local broken network appeared in partial borocarbides, and fine secondary borocarbide precipitated from the matrix. After tempering from 525 °C, the amount of precipitated borocarbide increased significantly. After heat treatment, the hardness of high‐boron high speed steel roll excelled 60 HRC, and its impact toughness excelled 8.0 J/cm². The single groove steel rolling amount of high‐boron high speed steel rolls increases by 500% than that of bainite cast iron roll, when the rolls are used in K₁ mill housing of bar mill.     

Thixotropy of Systems with Shear Thinning and Plastic Flow Behavior

The definition of the thixotropy is a decrease in viscosity with time in shear and a subsequent recovery of viscosity after the shear deformation is removed.We ...