中国五个城市的中期胎儿组织中几种元素含量的PIXE分析

应用质子激发Ｘ荧光分析法（ＰＩＸＥ）对我国五个城市的近５０例流产胎儿（５－６个月）的肝、脑、肾、肺、胃组织进行了１２种元素的含量分析，结果可见，广州地区胎儿的五个器官中的钙含量几乎均显著地低于其它四个地区（Ｐ＜０．０１）；昆明地区胎儿的五个器官中的铷含量均显著地高于其它四个地区（Ｐ＜０．０１）；上海地区胎儿的大部分组织中的铅含量均显著地高于其它四个地区（Ｐ＜０．０１）。比较胎儿元素谱与空气气液胶中     

用超热中子活化法测定大鼠肝脏亚细胞组分中的砷

采用差速离心分离技术与超热中子活化分析法 (ENAA) ,测定了大鼠肝脏亚细胞组分 (细胞核、线粒体、溶酶体、微粒体、胞液 )中As的质量分数 ,并对标准参考物质作对照分析。分析结果表明 :As在各亚细胞组分中并非均匀分布。As在微粒体中的质量分数最高 ,在细胞核中最低。用t检验比较了在中毒组大鼠和正常组大鼠肝脏中各亚细胞组分中As含量的差别 ,以及中毒组大鼠肝亚细胞组分之间的差异。发现上述两组肝亚细胞组分中As存在极显著性差异 (P <0 0 0 1)。在中毒组肝亚细胞组分中 ,微粒体中As的含量与胞液无显著性差异 (P >0 0 5 ) ,但与细胞核、线粒体、溶酶体存在明显的差异 (P <0 0 5 )。     

中子活化法研究硒在人体组织中的亚细胞分布

用细胞器的差速离心分离技术和中子活化分析法研究了微量元素硒在人体重要组织中的亚细胞分布 ,并用国际标准参考物质小牛肝 (NIST 15 77a)、马肾 (IAEA H8)等检验分析结果的准确性。结果表明 :不同个体的硒水平差异较大 ;在所研究的组织中 ,肾脏中硒含量最高。不同组织中硒的亚细胞分布模式明显不同 ,硒的浓度从高到低依次为 :肝脏 ,线粒体 >细胞核 >胞液 >溶酶体、微粒体 ;肾脏 ,细胞核 >线粒体 >胞液 >溶酶体、微粒体 ;心脏 ,细胞核、线粒体 >胞液、溶酶体、微粒体     

人肝癌细胞内多种元素分布特征的分子活化研究

为探讨微量元素在原发性肝癌亚细胞组分中的分布及在肝癌发生发展中的变化,采用分子活化分析方法测定了肝癌和正常肝脏细胞亚细胞组分中的17种不同宏量和微量元素的分布,t检验比较两者之间的元素含量的差别。结果发现Br、Ca、Cd和Cs在肝癌各亚细胞组分中的含量明显高于正常人,大部分具有统计学显著性差异。肝癌微粒体Fe明显低于正常人肝,为正常人的一半(P<0.05),而其它亚细胞组分均高于正常人肝。La和Ce的分布与Fe类似。Sb和Zn在肝癌细胞核中的含量则明显低于正常人肝(P<0.05、P<0.05)。K、Na在肝癌胞浆的含量明显高于正常人(P<0.05)。Ba和Rb在肝癌和正常肝脏的分布没有显著性差异。本文还探讨了Fe、Cd和K等元素含量的变化与肝癌发生的关系。肝癌与正常肝脏的亚细胞组分之间,多数微量元素的空间分布有着显著不同,提示微量元素在肝癌发生发展中起着重要作用。     

~(60)Coγ射线对小麦、玉米和黑麦根尖细胞亚微结构的影响

本实验对小麦、玉米和黑麦萌发种子进行~(60)Coγ射线照射,取根尖分生组织作电镜制片观察。剂量:77.20 Gy、144.75 Gy和289.50 Gy;剂量率:1.42±0.019 Gy/min。结果表明:随辐照剂量的增加和辐照后时间的延长,细胞的液泡化程度逐渐加强以致呈强烈液泡化状态。内质网膨胀形成带状、环状和网状液泡。内质网和高尔基体的活动与细胞的液化有极为密切的关系。细胞核变形并形成微核。线粒体嵴减少,基质呈电子透明态,最后双层膜局部破裂形成细胞内的残损结构。高尔基体、细胞膜及细胞壁等结构没有明显损伤。本文讨论了辐射处理后细胞的液泡化过程、微核的形成及细胞器的变化等。     

WR-2721对辐射所致脂类过氧化的影响Ⅱ——照射小鼠肝与脑亚细胞各部分脂类过氧化值

小鼠经850rad照射后第1、3、5、7和10天,肝与脑的亚细胞各部分脂类过氧化率均有不同程度的增高,如微粒体>线粒体>胞核。其峰值出现于照射后第3天或第5天。腹腔注射WR-2721可使照射后亚细胞各部分的脂类过氧化程度显著减轻。     

等离子体纳米探针在细胞成像中的应用

贵金属纳米材料具有局域表面等离子共振效应,由于其独特的物理、化学和光学性质,在纳米光子学、化学传感、靶向放射治疗、生物成像等领域得到日益广泛的应用。通过调控等离子体纳米颗粒的组成、形貌和尺寸,可以得到性质各异的散射光探针,并利用暗场显微镜对其进行观测。与荧光探针相比,等离子体纳米探针具有灵敏、稳定的优势,适合活细胞成像和对单个探针进行实时追踪。本文介绍了适用于暗场显微成像的等离子体纳米探针的最新进展;总结了其在观测细胞膜受体分布、原位检测细胞内各类生物分子、追踪胞内转运过程等方面的应用;并对暗场细胞成像的前景进行了展望。     

基于SDD与DPP的X荧光分析及其在光伏硅杂质元素分析中的应用

采用硅漂移探测器(SDD)和DPP数字脉冲处理器(DPP)相结合,以及双靶X光管激发系统的X荧光分析方法,测定了光伏硅中杂质元素的含量,并采用不同含量的国家标准物质元素,对其最低检测限、精密度、准确度、稳定性等进行了实验,以检验所研制设备及所建立方法的可行性和实用性。研究结果表明,运用该设备及方法所测得的数据,可满足欧盟ARTIST计划和美国太阳能工业协会对光伏硅中杂质元素的限制要求。     

XRF法无标分析人造金刚石原料锭中Fe、Ni、Cr、Co组分及其分布

介绍了用X射线荧光光谱(XRF)法无标分析人造金刚石原料锭样品的制备和测量方法.用车加工制备出了满足XRF测量的分析试样,应用Spectraplus无标分析软件实现了对人造金刚石原料锭中Fe、Ni、Cr、Co组分及其分布的无标分析,该方法简便、快速.     

应用中子活化分析技术测定人脑肿瘤亚细胞组分中的微量元素

采用密度梯度离心分离技术结合仪器中子活化分析技术,分析测定了人脑(正常和肿瘤)亚细胞组分中11种微量元素的浓度,并对其分布进行了讨论。     

人体肝脏微量元素的亚细胞分布

将超离心分离技术与中子活化分析法相结合,分析测定了正常人肝亚细胞组分中的微量元素。介绍了样品的采集制备、微量元素的实验测定,使用标准参考物质NBS-1577a,IAEA-H8校对了方法的可靠性。报道了人肝5种亚细胞组分(核、线粒体、溶酶体、微粒体、胞液)中8种微量元素的含量,并对其分布进行了初步研究。     

Trace metal distribution studies in river water by PIXE

Proton induced X-ray Emission (PIXE) has been used to measure the trace metals especially heavy metals in Chaliyar river water samples to assess the impact of pollutants from the industrial wastes. Water samples were collected in summer and rainy seasons from three different depths along the course of the river. Measurements were carried out with 2 MeV proton beam using a 3 MV tandem pelletron accelerator at Institute of Physics, Bhubaneswar. Results from the water Samples collected in both the seasons show that the concentrations of certain heavy metals like Hg, Zn and Pb are more than the prescribed limits. This is because of pollution due to industrial wastes, indicating a need for improvement in the industrial waste treatment.     

癌和正常组织细胞中钾元素的PIXE测定

应用质子激发Ｘ荧光技术（ＰＩＸＥ）对胃癌、肠癌、肺癌和癌细胞株的钾元素进行了测定，结果发现组织中的钾浓度明显高于正常组织，提示癌细胞高钾可能与细胞分裂速度有关。     

Elemental and mineral characterisation of Coastal Antarctic Aerosols in snow using PIXE and SEM-EDAX

The chemical constituents of snow from a 3 m pit sampled at a coastal Antarctic site were characterised by means of PIXE and SEM-EDAX. Oxygen isotope dating revealed that the pit spanned an 8-year period, from 1986 to 1994. Concentrations measured by PIXE ranged from less than 1 ng g⁻¹ of H₂O for Cu, and Zn to several tens of ng g⁻¹ for Si, S and Cl. The major elements found were Si, S, Al, and Na, which contributed more than 75% of the element loading. Snow layers with elevated Cl concentration were regularly found along the pit. The mineralogy of the insoluble particles determined by SEM-EDAX analyses showed that quartz, plagioclase and clays were the prevalent minerals. The proportion of each element in the insoluble phase was comparable with that previously found in similar studies.     

山东省胃癌高低发区健康人发中微量元素的PIXE分析

用ＰＸＩＥ方法测定山东省胃癌高发区栖霞县和低发区苍山县高发年龄组（５０－６０岁）的健康人发中的微量元素,结果表明前人发中的Ａｓ,Ｃｏ,Ｆｅ,Ｃｒ显著高于后者,而Ｓｅ则相反。     

山东省胃癌高低发地区主要食物中微量元素的PIXE分析

介绍了用PIXE技术分析食物中微量元素的方法,给出了山东省胃癌高发区栖霞县和低发区苍山县当地产主要食物的微量元素谱．t检验结果显示,栖霞县食物中Sr、Ni、Cu、Mn和Fe的含量显著高于苍山县,而Se的含量则相反．     

Study by PIXE method of trace elements transferred from prostheses to soft tissues and organs

Some metallic prostheses inserted in human hip undergo physico-chemical modification, a few years after their implantation. Tissues surrounding these prostheses are damaged by metallic element transfer. Surgeons in Clermont-Ferrand Hospital (France) recover tissues of abnormal coloration that were in contact with metallic implants. PIXE technique (particles induced X-ray emission) with a 400 μm proton beam and 3 MeV of energy is an efficient technique to analyze these tissues and to detect elements, which are transferred from prosthesis to tissues. PIXE analyses were carried at the CERI-CNRS Laboratory. We have applied this method to determine qualitatively and quantitatively trace elements migration from metallic implants to surrounding tissues and organs, like kidney, spleen, liver, lymphatic gland and lung.     

Study of particulate emissions near a steel plant in Genova by continuous sampling and PIXE hourly analysis

The particulate emissions near a large steel plant located in a densely inhabited suburb of the town of Genova (Italy) have been studied for a period of six months. We have used two-stage continuous streaker samplers and subsequent PIXE analysis with hourly resolution, to follow both seasonal and daily trends. The first streaker sampler remained installed very close to the plant cokery and furnaces, while another sampler was moved to different locations. Samples have been analysed by PIXE, deducing concentrations for elements from Na to Pb. During part of the campaign, the aerosol fractions with aerodynamic diameter (D_ae) < 2.5 μm (fine fraction) and with 2.5 < D_ae < 10 μm (coarse fraction) have been separately collected. We have measured and analysed about 8500 PIXE spectra: the steel plant emissions have been identified to some extent and resolved from other aerosol sources.