Detection by a solid phase independent enzyme immunoassay of monoclonal anti-idiotypic antibodies against monoclonal antibodies neutralizing Semliki Forest virus and encephalomyocarditis virus

3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase (EC 1.1.1.34) is the rate limiting step in the mevalonate pathway that produces isoprenoids and cholesterol. Inhibitors of HMG-CoA reductase are teratogenic in vivo and induce neural tube defects in rat embryo culture, effects which appear unrelated to cholesterol deficiency. This study is the first to localize HMG-CoA reductase mRNA by in situ hybridization (ISH). Expression of reductase mRNA was examined in post-implantation rat embryos, and for control purposes in rat liver and UT-1 cells, using a digoxigenin-11 (dig-11) labelled cRNA probe. Eighteen-day fetal liver showed heavy but patchy hybridization, and adult rat liver showed strong hybridization only on some periportal hepatocytes, which was absent in livers of fasted animals. UT-1 cells stimulated to overexpress HMG-CoA reductase mRNA were strongly positive with the same probe. Control hybridizations with sense strand RNA probe, or with cRNA probe on pre-RNased tissue were negative. Strong hybridization signal for HMG-CoA reductase mRNA was observed in all tissues of the post-implantation rat embryo, from egg cylinder to 30 somite stages (7 to 12 days). Heavy signal was noted in primitive ectoderm and neural tube. The wide embryonic and extraembryonic distribution and abundance of HMG-CoA reductase mRNA may reflect developmental requirements for products of the mevalonate pathway, e.g., isoprenoids for post-translational farnesylation of p21ras.     

Complete physical map of the common deletion region in Williams syndrome and identification and characterization of three novel genes

Williams syndrome (WS) is a contiguous gene deletion disorder caused by haploinsufficiency of genes at 7q11.23. We have shown that hemizygosity of elastin is responsible for one feature of WS, supravalvular aortic stenosis (SVAS). We have also implicated LIM-kinase 1 hemizygosity as a contributing factor to impaired visual-spatial constructive cognition in WS. However, the common WS deletion region has not been completely characterized, and genes for additional features of WS, including mental retardation, infantile hypercalcemia, and unique personality profile, are yet to be discovered. Here, we present a physical map encompassing 1.5 Mb DNA that is commonly deleted in individuals with WS. Fluorescence in situ hybridization analysis of 200 WS individuals shows that WS individuals have the consistent deletion interval. In addition, we identify three novel genes from the common deletion region: WS-betaTRP, WS-bHLH, and BCL7B. WS-betaTRP has four putative beta-transducin (WD40) repeats, and WS-bHLH is a novel basic helix-loop-helix leucine zipper (bHLHZip) gene. BCL7B belongs to a novel family of highly conserved genes. We describe the expression profile and genomic structure for each of these genes. Hemizygous deletion of one or more of these genes may contribute to developmental defects in WS.     

贵州作为全国磷复肥建设基地磷化工产业发展前景广阔

分析国际、国内高浓度磷复肥的需求与产能形势,贵州发展磷化工产业的优势条件;提出对贵州省磷化工产业发展的若干建议,认为我国磷复肥产能虽然过剩,但作为全国磷复肥建设基地的贵州省磷化工产业仍具有广阔的发展前景.     

影响涂料耐磨性能的主要因素

研究了影响涂料耐磨性能的主要因素，试验表明，填料的种类，粒径，含量，涂料基料的种类，配比对涂层的耐磨性能影响较大，利用扫描电镜图对涂料的耐磨过程及机理进行了探讨，证明在涂层磨损过程中，有选择性磨损现象出现，这在一定程度上，减轻了涂层的磨损过程。     

炮采放顶煤工作面采空区顶板抽放瓦斯实践

文章介绍了高瓦斯炮采放顶煤工作面采空区煤层顶板抽放瓦斯的实践,通过对钻场中钻孔抽放过程的跟踪测试、观察、归纳分析,总结出提高瓦斯抽放效率的最佳顶板裂隙带高度,并对关键性技术要点和裂隙带高度的确定提供了理论判定方法。     

微机智能重量传感检测系统􀀁

本文阐述了一种微机智能重量传感检测系统的基本原理及设计方法 .其中包括 :激励信号的产生 ,信号的频谱分析 ,滤波器设计 ,PWM信号的产生等     

水热沉积电压对C-AlPO_4涂层显微结构的影响

以方石英型磷酸铝(C-A1PO4)粉体为原料,异丙醇为溶剂,碘为荷电介质,采用水热电泳沉积方法在涂有SiC涂层的碳纤维增强碳(C/C-SiC复合材料表面制备了C-A1PO4外涂层.借助X射线衍射和扫描电镜表征了涂层的晶相组成和显微结构.研究了沉积电压对C-A1PO4涂层显微结构的影响,并测试了涂层的抗氧化性能.结果表明:在180～220V范围内,水热沉积电压对涂层的显微结构有较大的影响,220V时制备的涂层致密均匀.涂层的沉积量以及涂层与基体的结合强度随着沉积电压的升高而增加;单位面积沉积量与时间的二次方根之间符合线性关系.与包埋法制备的SiC涂层相比,水热电泳沉积法制备的C-A1PO4涂层具有更好的抗氧化性能,涂层样品在1500℃的空气中氧化37h后质量损失仅为0.53%.     

稀土配合物杂化材料的制备与性能研究

综述了近年来稀土配合物杂化材料的制备和性能．按基质的不同，稀土配合物杂化材料可分为稀土配合物，无机杂化材料，稀土配合物，有机杂化材料以及稀土配合物，混合基质杂化材料。本文对以上3种杂化材料的优缺点进行了较为详细的分析，并提出一步法制备稀土配合物杂化材料，以简化合戍步骤，提高稀土配合物在基质分布的均匀性，因而该方法有望戍为制备稀土配合物杂化材料的一个重要发展方向。     

微乳液组分对体系增溶水量的影响及纳米羟基磷灰石的制备

应用电导率法研究了TritonX-100/正戊醇／环己烷体系中各组分及条件对微乳液最大增溶水量的影响。结果表明：当表面活性剂TritonX-100用量为3ml，助表面活性剂选正戊醇用量为1ml，环己烷为油相，温度为48℃，Ca（NO3）2溶液与（NH4）2HPO4溶液分别为0．24和0．14mol／L时，体系增溶水量最大，可得到较高产率的纳米羟基磷灰石。并且用XRD和TEM手段对产物进行了表征。     

Management of sternal and abdominal wounds in a pediatric heart transplant patient

A 14-year-old girl with congenital heart disease underwent ventricular assist device placement before cardiac transplantation. The inability to close her abdominal fascia necessitated the placement of Prolene mesh, which subsequently became exposed and contaminated when her incision dehisced. Stable closure was obtained with Vicryl mesh and a rectus abdominis turnover flap. Her posttransplant course was notable for compression of the donor heart, necessitating prolonged open sternotomy. She failed an attempt at delayed sternal closure due to compression of the right ventricle by the sternum. In addition to standard pectoralis advancement flaps, a pedicled osseous sternal flap based on her left internal mammary artery was developed to avoid ventricular compression yet still provide some protection to the mediastinum. Alternative uses of this vascularized bone flap to assist with chest wall reconstruction are discussed.