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1.
Radionuclide imaging of HER2 expression in tumours may enable stratification of patients with breast, ovarian, and gastroesophageal cancers for HER2-targeting therapies. A first-generation HER2-binding affibody molecule [99mTc]Tc-ZHER2:V2 demonstrated favorable imaging properties in preclinical studies. Thereafter, the affibody scaffold has been extensively modified, which increased its melting point, improved storage stability, and increased hydrophilicity of the surface. In this study, a second-generation affibody molecule (designated ZHER2:41071) with a new improved scaffold has been prepared and characterized. HER2-binding, biodistribution, and tumour-targeting properties of [99mTc]Tc-labelled ZHER2:41071 were investigated. These properties were compared with properties of the first-generation affibody molecules, [99mTc]Tc-ZHER2:V2 and [99mTc]Tc-ZHER2:2395. [99mTc]Tc-ZHER2:41071 bound specifically to HER2 expressing cells with an affinity of 58 ± 2 pM. The renal uptake for [99mTc]Tc-ZHER2:41071 and [99mTc]Tc-ZHER2:V2 was 25–30 fold lower when compared with [99mTc]Tc-ZHER2:2395. The uptake in tumour and kidney for [99mTc]Tc-ZHER2:41071 and [99mTc]Tc-ZHER2:V2 in SKOV-3 xenografts was similar. In conclusion, an extensive re-engineering of the scaffold did not compromise imaging properties of the affibody molecule labelled with 99mTc using a GGGC chelator. The new probe, [99mTc]Tc-ZHER2:41071 provided the best tumour-to-blood ratio compared to HER2-imaging probes for single photon emission computed tomography (SPECT) described in the literature so far. [99mTc]Tc-ZHER2:41071 is a promising candidate for further clinical translation studies.  相似文献   
2.
本文介绍了265/70R17115S规格雪地轮胎的设计,外轮廓方面,轮胎的设计外直径797 mm,充气断面宽282 mm,轮胎的行驶面宽207 mm,设计行驶面弧高度8.5 mm,胎圈着合直径取值430 mm,轮胎的胎圈着合宽度237.8 mm,轮胎的断面水平轴位置取值0.96746;轮胎的胎面花纹设计分为长型花纹(M型、L型)与短型花纹(S型),3种花纹为交替变节距呈现,花纹深度10.4 mm,花纹饱和度68.16%。轮胎的施工设计方面:胎面挤出部件为全分层设计,可更好的区分胶种,功能性更强,胎侧挤出部件为双复合设计,冠带层的1#、2#带束层材料使用3×0.30HT钢丝帘线,胎圈部位的钢丝圈为斜六角形结构,更好的保证了成品断面钢丝圈部位,切割后呈近圆形;胎胚成型使用的设备是萨驰一次法成型机,胎胚硫化使用的设备是韩国东和液压硫化机,硫化工艺为氮气硫化。生产的成品轮胎的外缘尺寸、强度性能和耐久性能等均满足国家标准要求。  相似文献   
3.
周赛  李龙  刘宜树 《同位素》2019,32(3):171-177
与裂变型99Mo-99mTc发生器相比,凝胶型99Mo-99mTc发生器制备99mTc具有工艺简单、产生的放射性废物容易处理、对环境影响小等优点。本文主要论述了凝胶型99Mo-99mTc发生器与裂变型99Mo-99mTc发生器的区别,堆照生产99Mo原料和凝胶材料的研究进展,凝胶结构以及凝胶组分等多种条件因素对凝胶型99Mo-99mTc发生器性能的影响等,并对低比活度99Mo生产99mTc的研究进展进行综述。  相似文献   
4.
Urban development has an important influence on the energy consumption of transportation. To develop public transportation is one of the important ways to decrease the energy consumption of urban transportation. It is very urgent to upgrade technology to reduce the energy consumption and emissions of the vehicles constantly. The popularization of hydrogen fuel cell vehicles is the trend of the future automobile industry, which can effectively reduce traffic energy consumption and alleviate urban pollution. This article analyzes the impact of urban development on public transport and private transportation energy consumption from 2013 to 2015; and uses hydrogen fuel cell vehicles alternatives in urban public transport as a scenario. It shows that urban economic development can effectively reduce public transport. Population growth will increase greatly energy consumption of public transport, while larger cities with reasonable spatial density can reduce traffic energy consumption. Moreover, hydrogen fuel cell vehicles can effectively reduce the energy consumption and pollution emissions of urban transportation during operating. Based on the above conclusions, this article will eventually provide targeted recommendations for the development of Chinese cities, public transport, and hydrogen fuel cell vehicles.  相似文献   
5.
α‐Melanocyte stimulating hormone (α‐MSH) derivatives target the melanocortin‐1 receptor (MC1R) specifically and selectively. In this study, the α‐MSH‐derived peptide NAP‐NS1 (Nle‐Asp‐His‐d ‐Phe‐Arg‐Trp‐Gly‐NH2) with and without linkers was conjugated with 5‐(bis(pyridin‐2‐ylmethyl)amino)pentanoic acid (DPA‐COOH) and labeled with [99mTc]Tc‐tricarbonyl by two methods. With the one‐pot method the labeling was faster than with the two‐pot method, while obtaining similarly high yields. Negligible trans‐chelation and high stability in physiological solutions was determined for the [99mTc]Tc‐tricarbonyl–peptide conjugates. Coupling an ethylene glycol (EG)‐based linker increased the hydrophilicity. The peptide derivatives displayed high binding affinity in murine B16F10 melanoma cells as well as in human MeWo and TXM13 melanoma cell homogenates. Preliminary in vivo studies with one of the [99mTc]Tc‐tricarbonyl–peptide conjugates showed good stability in blood and both renal and hepatobiliary excretion. Biodistribution was performed on healthy rats to gain initial insight into the potential relevance of the 99mTc‐labeled peptides for in vivo imaging.  相似文献   
6.
The direct Z-scheme photocatalysts for overall water decomposition have aroused much concern on account of their strong redox ability and efficient separation of photogenerated electron-hole pairs. In the present work, we have constructed the two dimensional (2D) van der Waals (vdW) MoSe2/SnS2 heterojunction and investigated its electronical and optical properties by applying hybrid functional calculations. The calculated band structures have implied that the MoSe2/SnS2 heterostructure as a direct Z-scheme photocatalyst can make the best of visible light. The induced built-in electric field can effectively improve the separation efficiency of the photoinduced carriers. Moreover, compared with the MoSe2 and SnS2 monolayers, the absorption intensity of MoSe2/SnS2 heterojunction is reinforced in the visible light range. Therefore, MoSe2/SnS2 nanocomposite shows a bright application prospect as a direct Z-scheme visible-light-driven photocatalyst for overall water splitting.  相似文献   
7.
The aim of this study is to describe the development and application of a web-based decision support tool (ViRTUE) for performing climate risk evaluations of water supply systems. The tool is designed for small-scale water utilities in the northeastern United States that may lack the resources for detailed climate change risk investigations. Development of this tool demonstrates a relatively new approach to web application development using the Shiny framework for the R programming language to create an interactive environment for stakeholders and water managers to explore climate vulnerabilities. Using a decision-scaling framework, the tool allows the user to perform a climate stress test to evaluate the performance and vulnerability to water supply shortfalls of local reservoir systems over a wide range of potential climate change scenarios using a generic systems model. Probabilities of future climate conditions derived from climate projections then help inform utility operators of impending risk.  相似文献   
8.
99mTc-TEBO为临床批准的快速心肌灌注显像药物,该药物初始摄取高,但心肌滞留不稳定,为此,本研究通过优化其硼酸结构,分别制备标记物99mTc-2SP、99mTc-4LPA及99mTc-2MDM,制备时间均为30 min,均为无色澄明液体,放化纯度均>95%,分别在健康小型猪体内进行SPECT动态显像,并与99mTc TEBO进行对比。结果表明:99mTc-TEBO注射后0~5 min,左室心肌快速摄取,但随后心肌放射性迅速洗脱,在10 min时心肌约洗脱至峰值的75%,与心血池放射性浓度比值为1.63。99mTc-2SP引入2-甲磺酰基吡啶-5-硼酸基后心肌初始摄取高,心肌滞留时间明显延长,心肌洗脱较缓慢,左室心肌均清晰显影,在第10 min时心肌摄取仍可保持峰值的95%,与心血池放射性浓度比值为3.75,明显高于99mTc-TEBO。而另外两种显像剂99mTc-4LPA和99mTc-2MDM在注射后15 min内显像不理想。因此,99mTc-2SP是有潜力的心肌灌注显像药物。  相似文献   
9.
99Mo的衰变子体99mTc是核医学领域中应用最广泛的放射性同位素,近年全球主要的99Mo生产堆面临着非计划检修及关停退役等问题,导致其供应不稳定,因此多个发达国家已在积极开发99Mo生产的替代性技术。本文介绍了多种利用粒子加速器代替反应堆生产99Mo的技术路线,总结了电子加速器生产99Mo的国内外研究进展,详细论述了加速器性能指标和照射装置与靶件设计、99mTc分离提取、100Mo回收利用以及废物管理等关键技术,为国内有关技术的基础、应用研究与电子加速器生产99Mo的商业化提出建议。  相似文献   
10.
Natural rubber nanocomposites filled with hybrid fillers of multi-walled carbon nanotubes(CNTs) and carbon black(CB) were prepared. CNTs were ultrasonically modified in mixture of hydrogen peroxide(H_2O_2) and distilled water(H_2O). The functional groups on the surface of CNTs, changes in nanotube structure and morphology were characterized by Fourier transform infrared spectroscopy(FT-IR), Raman Spectroscopy, and transmission electron microscopy(TEM). It shows that hydroxyl(OH·) is successfully introduced. The surface defects of modified CNTs were obviously higher than those of original CNTs, and the degree of agglomeration was greatly reduced. Thermal conductivity of the composites was tested by protection heat flow meter method. Compared with unmodified CNTs/CB filling system, the thermal conductivity of hybrid composites is improved by an average of 5.8% with 1.5 phr(phr is parts per hundred rubber) of hydroxyl CNTs and 40 phr of CB filled. A three-dimensional heat conduction network composed of hydroxyl CNTs and CB, as observed by TEM, contributes to the good properties. Thermal conductivity of the hybrid composites increases as temperature rises. The mechanical properties of hybrid composites are also good with hydroxyl CNTs filled nanocomposites; the tensile strength, 100% and 300% tensile stress are improved by 10.1%, 22.4% and 26.2% respectively.  相似文献   
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