应用X荧光分析法测定体内骨铅含量方法初探

Ahlgren等[1]于 1976年首次报道了体内骨铅测定的方法。他们采用5 7Co作为激发源 ,记录指骨铅激发后放出的X射线 ,测定得到骨中铅的含量。国内黄士斌等[2 ]曾采用 12 5I为激发源 ,以石蜡胫骨模型测定铅放出的LX射线 ,但该方法灵敏度不高。本文采用10 9Cd作为激发源 ,探讨铅作业工人的活体胫骨铅含量测定方法。1　材料和方法1 1　骨铅X荧光体内测量系统的建立以10 9Cd作为放射源 ,用高纯锗作为探测器 ,接受铅放出的KX射线 ,信号经放大处理 ,数字转换后与计算机联结进行数据分析 ,结果以每克骨中含 μg铅表示即 μg/g。铅的K系X射线中 ,…     

体内X射线荧光骨铅检测新进展

讨论了铅的危害,认为骨铅应作为铅中毒新的生物标记。介绍了体内X射线荧光(in vivo XRF)骨铅原理,比较了三类检测各类系统的优缺点,综述了检测系统新进展。     

用荧光原位杂交技术对医用诊断X射线工作者染色体畸变的研究

目的 用荧光原位杂交(RIS H)技术研究小剂量职业受照者的辐射损伤运期效应。方法用4号和7号全染色体探针，分析25名早期X射线工作者和10名对照者外周血淋巴细胞染色体畸变，并用Giemsa染色验证。结果 X射线工作者的易位占其染色体总畸变的84％，其他各种略变率分别为插入(Ins)2％，双着丝粒(Dic)5％和无着丝粒断片(Ace)10％;X射线工作者的染色体易位率和总畸变率均明显高于对照组(P＜0．01)，染色体易位随着放射工龄增加而增加。1她年前工作的x射线工作者的染色体易位与同期对照组相比，差异有非常显著性(P＜0．01)；1965年后工作的X射线工作者的染色体易位与同期对照组相比，差异无显著性(P＞0．05)。结论 医用诊断X射线工作者外周血淋巴细胞染色体畸变以易位为主。     

对X射线直接荧光胸部透视效能的评价

直接荧光透视是我区历年来在从业人员年度预防性健康体检中用以筛查“五病”中活动性肺结核的常规胸部Ｘ射线检查法。为更合理地应用Ｘ射线，现对我区１９９０～１９９８年６２３７８人次的从业人员年度预防性健康体检中活动性肺结核阳性检出率做回顾性分析，以评价直接荧光胸部透视在健康体检中的效能。１　１９９０～１９９８年从业人员年度预防性健康体检总数６２３７８人次，共检出活动性肺结核５人，总阳性率为０８×１０－４。其中４年无阳性病例发现，其余５年每年各发现１例，各年度阳性检出率均低于１０－３，详见表１。２　５例…     

便携式X线荧光分析仪用于现场油漆涂层铅含量检测的研究

目的:了解便携式X线荧光分析仪(XRF)用于测定油漆涂层铅含量的可靠性。方法:选取不同颜色的油漆涂层,分别用便携式X线荧光分析仪和原子吸收法测定其铅含量,分别作统计检验和计算灵敏度、特异度和约登指数来评价方法的可靠性。结果:分别使用XRF和FAAS法对28个油漆涂层进行了抽样检测,配对t检验两种方法的检验结果差别没有显著意义(t=-0.408,P=0.58),以大于或等于5000 mg/kg作为油漆铅超标的标准时XRF的灵敏度为80%,特异度为91%,约登指数=71%。应用XRF对广州市22间公园内的儿童游乐场所和60间幼儿园中油漆涂层进行铅含量检测,超标率38.5%。结论:XRF是一种现场筛查油漆铅含量的简单可行方法。     

用能量色散X射线荧光光谱仪测定胆结石中的钙和碘

用能量色散X射线荧光技术分析了胆结石。对病人胆结石中钙和碘的浓缩情况进行了观察。通过2π几何位置标准加入法用环形铁放射源测定了钙含量和用环形镅放射源测定了碘含量。用硅(锂)探测器测定了胆结石中的钙和碘的含量。     

水中微量砷的波长色散X射线荧光光谱测定法

目的建立水中微量砷的波长色散X射线荧光光谱测定法。方法水样在氦气的保护下直接进样,样品量为7 ml,耗时100 s,采用波长色散X射线荧光光谱法测定As Kα1谱线的强度,以确定水样中砷的含量。结果该方法在2.05~200mg/L浓度范围内的线性关系良好,r=0.999 8。该方法的检出限为0.3 mg/L,平均回收率为97.1%~107.0%,RSD1.45%。结论该方法具有快速、灵敏、准确、环保的特点,适用于对大批水样的砷进行长期、频繁监测。     

X射线荧光光谱法在法庭科学中的应用

作为物质组成分析的重要技术手段之一,X射线荧光光谱检测技术(XRF)现已运用于生物、工业、药物、食品等领域,同时,在法庭科学领域也得到了广泛的应用,可以为侦查破案提供线索,为证实犯罪提供科学的依据。     

薄样法X射线荧光光谱（XRFS）人体肾结石多组分测定

要本文应用X射线荧光光谱法(XRFS)测定了人体肾结石中多种组分的含量。针对肾结石样品量很少的特点，我们采用薄样法的制样方法。整个测定快速、简便。可一次性测定人体肾结石中的十一种组分，省去了某些方法中复杂的化学处理过程，对今后肾结石成份的测定及肾结石成因的深入研究具有实用价值。     

In vitro vs in vivo Pb effects on brain protein kinase C activity

Alteration of normal protein kinase C (PKC) function by environmental Pb exposure during neurodevelopment is hypothesized to be an important mechanism of toxicity underlying neurologic impairment. Previous studies have reported widely varying effects of Pb on PKC, possibly in part because of differences in in vitro and in vivo models used in those studies. Therefore, we tested the hypothesis that, with comparable tissue Pb levels, the effects of in vitro Pb exposure on brain PKC are the same as the effects caused by in vivo Pb exposure of intact animals. For chronic in vivo Pb exposure, female Long-Evans rats were exposed to Pb or vehicle from postnatal days 1 to 34-36 (n=10/treatment). For in vitro Pb exposure, homogenate of the frontal cortex region was exposed directly to Pb in an amount comparable to that accumulated in brain during chronic in vivo Pb exposure. Brain Pb levels were measured using ultraclean techniques and inductively coupled plasma mass spectrometry. PKC activity was subsequently determined in cytosolic and membrane subcellular fractions in the frontal cortex, hippocampus, and remaining brain regions. Results indicate that brain Pb levels following in vivo Pb exposure were increased approximately 20-fold above those of nonexposed animals (vehicle group [Pb] approximately 130ng Pb/g dry wt.). However, in vivo Pb exposure did not measurably alter brain PKC activity in the regions tested. In contrast, in vitro Pb exposure significantly increased PKC activity by approximately 20% in the frontal cortex homogenate membrane subcellular fraction. These results indicate that Pb added in vitro caused more dramatic effects than those produced by a comparable amount of Pb in the tissue from in vivo exposure. While the mechanisms underlying these outcomes are not clear, they suggest that in vitro models might not accurately reflect effects of chronic low-level in vivo Pb exposure.     

染铅大鼠骨髓NOs和NO的变化

目的 探讨染铅对大鼠骨髓一氧化氮合酶（NOS）活力、一氧化氮（NO）含量的影响及其与血铅相互关系。方法 Wistar大鼠经饮水（加0，18．4，184．0mg/L醋酸铅，分别供对照组、低剂量组、高剂量组自由饮用）染毒，测定骨髓NOS活力、NO含量。结果 NOS活力高剂量染铅组在7d、14d时均较对照组和低剂量组高（P＜0．05），其余时点各组间差异无显著性（P＞0．05），NO含量染铅高剂量组在7d、14d时均较对照组和低剂量组高（P＜0．05），60d各剂量组间差异无显著性（P＞0．05），90d高剂量组显著低于对照组（P＜0．05）。结论 染铅导致大鼠骨髓毒性，引起骨髓NOS活力、NO含量改变，表现为染铅早期骨髓NOS活力、NO含量升高，晚期骨髓NOS活力、NO含量降低；但慢性染铅对骨髓NOS活力、NO含量影响的生理机制有待进一步研究。     

云南省野生食用菌铅含量调查

目的对云南省滇中地区出的野生食用菌中铅含量进调查,为食物资源的开发和综合利用提供参考依据。方法尽可能多地收集野生食用菌品种,按GB/T5009.12-2003《食品卫生检验方法理化部分食品中铅的测定方法》石墨炉原子吸收光谱法进行分析。结果经对27种新鲜野生食用菌进行检测,最高铅含量2.4mg/kg(干巴菌,曲靖)。除干巴菌外,其余品种铅含量(平均值)均低于1.0mg/kg。结论云南省野生食用菌中铅含量除干巴菌超标外,其余食用菌中的铅含量均达到国标要求。     

铅暴露对学龄前儿童免疫球蛋白IgE影响的研究

目的 :探讨低水平铅暴露对学龄前儿童免疫球蛋白 Ig E的影响。方法 :用石墨炉原子吸收光谱法对 2 1 7名学龄前儿童进行血铅浓度筛查 ,用酶联免疫吸附试验 ( ELISA)检测不同血铅水平对学龄前儿童免疫球蛋白 Ig E的影响。结果 :高铅组 (血铅≥ 0 .48μmol/L)学龄前儿童Ig E水平与低铅组 (血铅 <0 .48μmol/L)比较具有升高趋势 ,但无统计学意义 ( P>0 .0 5 ) ;高铅组血铅浓度与 Ig E水平呈正相关 ( r=0 .5 0 ,P<0 .0 1 ) ;女童高铅组 Ig E水平与低铅组比较显著升高 ( P<0 .0 5 )。结论 :铅中毒具有刺激学龄前儿童 Ig E的产生 ;铅暴露对学龄前儿童 Ig E水平的影响具有性别差异     

温度氧分压pH在体综合测试仪的研制

本文介绍了一种新型的使用针状微型传感器的温度，氧分压和ｐＨ值在体综合测试仪。     

锌对铅亚慢性暴露小鼠脑铅含量的影响

[目的]研究微量元素锌对铅亚慢性暴露小鼠脑铅水平的影响,探索能拮抗铅毒性的锌剂量。[方法]健康昆明种小鼠随机分成6组。空白对照组灌胃蒸馏水;铅染毒组灌胃0.8 mg/10 g体重醋酸铅溶液;锌对照组灌胃高剂量醋酸锌溶液;加锌实验组分别灌胃3个剂量（低、中、高）的醋酸锌及0.8 mg/10 g体重的醋酸铅混合溶液。每3天灌胃1次,观察小鼠体重变化及死亡情况,受试3个月后处死,用石墨炉原子吸收光谱法测定小鼠的脑铅含量。[结果]各剂量锌实验组小鼠的脑铅含量低于铅染毒组,与空白对照组类似,且各锌实验组间小鼠脑铅含量类似。[结论]低、中、高剂量锌均能降低小鼠脑铅含量,锌可以拮抗铅在小鼠脑部的残留,低剂量锌可以拮抗铅的毒性。     

离体和在体消毒方法相关性的初步研究

目的:探索建立以猪皮和仿真皮作为载体代替人手的离体消毒模拟现场试验方法。方法:以金黄色葡萄球菌、铜绿假单胞菌,大肠埃希菌,粘质沙雷氏菌为试验菌,参照《消毒技术规范》方法,采用消毒剂对皮肤消毒模拟现场试验方法进行试验研究。结果:离体模型中,仿真皮消毒模拟现场试验结果和皮肤消毒模拟现场试验结果的细菌杀灭对数值均大于3.0,猪皮消毒模拟现场试验结果的细菌杀灭对数值均大于2.0,离体仿真皮消毒模拟现场试验结果与人手消毒模拟现场试验的结果一致,离体猪皮消毒模拟现场试验细菌减少率相对较低,但与在体试验结果有较好的相关性。结论:离体仿真皮消毒模拟试验与在体皮肤试验结果相近,同时仿真皮之间结果重复性良好,操作简单可控,省时,对防止交叉感染有重要意义,在消毒产品的效果评估中可以替代在体皮肤模拟现场试验。     

In vivo measurements of lead in fingerbone in active and retired lead smelters

 Object. The aim of this study was to determine the bone lead concentration in lead smelters and reference subjects, relate them to the lead concentration in blood (B-Pb) and urine (U-Pb), and to use the measured bone lead to calculate a biological half-life for lead in bone. Method and design. The lead concentration in the second phalanx of the left index finger (bone-Pb) was determined in vivo using an X-ray fluorescence technique. The study population comprised 89 smelters with a history of long-term exposure to lead (71 active and 18 retired) and 35 reference subjects (27 active and 8 retired) with no known occupational exposure to lead. Bone-Pb was related to the previous lead exposure, estimated as a time-integrated B-Pb (CBLI). Results. The retired smelters had the highest bone-Pb (median value 55 μg/g wet weight, as against 23 μg/g in active smelters) and 3 μg/g in the reference subjects. A strong positive correlation was observed between the bone-Pb and the CBLI among both active (r _s =0.73; P<0.001) and retired (r _s =0.71; P=0.001) smelters. The corresponding correlations between the bone-Pb and the period of employment were of the same magnitude. For retired workers, there were positive correlations between the bone-Pb and the B-Pb (r _s =0.58; P=0.011) and U-Pb (r _s =0.56; P=0.02). Multiple regression analyses showed that bone-Pb was best described by the CBLI, which explained 29% of the observed variance (multiple r ²) in bone-Pb in active workers and about 39% in retired workers. The estimated biological half-life of bone-Pb among active lead workers was 5.2 years (95% confidence interval 3.3–13.0 years). Conclusions. The high bone-Pb seen in retired workers can be explained by the long exposure periods, the higher exposure levels in earlier decades, and the slow excretion of lead accumulated in bone. The importance of the skeletal lead pool as an endogenous source of lead exposure in retired smelters was indicated by the associations between the B-Pb or U-Pb, on the one hand, and the bone-Pb, on the other. In active workers, the ongoing occupational exposure was dominant. The in vivo X-ray fluorescence technique is still mainly a research tool, and more work has to be done before it can be used more widely in clinical practice. However, over the next decade we can anticipate retrospective, prospective and cross-sectional epidemiological studies in which bone lead determinations reflecting the previous lead exposure in both occupationally and nonoccupationally lead exposed populations are related to various types of adverse health outcomes. Such studies will improve our knowledge of dose–response patterns and provide data that will have an impact on hygienic threshold limit values and prevention of lead-induced diseases. Received: 2 October 1995/Accepted: 8 March 1996     

南昌市卡片类玩具和文具中铅含量的调查

目的　了解南昌市市场上儿童文具和卡片类玩具中铅的含量。方法　抽检市售铅笔样品 2 4份、2种品牌蜡笔样品2 0份、卡片贴纸 16份 ,用火焰原子分光光度计测定铅含量 ,对结果进行统计分析。结果　儿童铅笔中的铅含量为(12 9.90± 5 2 .5 3 )mg/kg ,蜡笔中的铅含量为 (5 5 .15± 2 1.2 3 )mg/kg ,玩具卡片贴纸中铅含量为 (75 .2 9± 2 4.65 )mg/kg ,经过统计分析发现 2种蜡笔铅含量差异有显著性 ,铅笔、蜡笔和卡片类玩具之间差异亦均有显著性。结论　 60份儿童文具和玩具铅含量大都符合国家标准 ,仅有 1份铅笔样品超过国家标准。为保护儿童身体健康 ,国家应完善管理措施 ,尽可能降低其中铅含量。