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1.
深圳特区土壤和建筑材料中的放射性水平   总被引:4,自引:0,他引:4       下载免费PDF全文
应用200只天鼠研究了241Am内污染时四种络合剂(Ca-DTPA, Zn-DTPA,嗤胺酸钠盐和H-73-IO)钓促排效果.实验目的是为241Am内污染治疗确定首先促排药物及制定最佳促排方案.实验结果表明:在四种结合剂中Ca-DTPA和Zn-DTPA促排效果为最佳,能使骨241Am含量降低到对照组的10%,肝241Am含量降低到对照组的5%左右.喹胺酸钠盐在降低骨、肝241Am含量方面也有效(统计上与DTPA无显著差别),但能导致肾脏241Am蓄积,甚至略高于对照组.H-73-10虽有-些效果,但远不及DTPA.  相似文献   

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应用200只天鼠研究了241Am内污染时四种络合剂(Ca-DTPA, Zn-DTPA,嗤胺酸钠盐和H-73-IO)钓促排效果.实验目的是为241Am内污染治疗确定首先促排药物及制定最佳促排方案.实验结果表明:在四种结合剂中Ca-DTPA和Zn-DTPA促排效果为最佳,能使骨241Am含量降低到对照组的10%,肝241Am含量降低到对照组的5%左右.喹胺酸钠盐在降低骨、肝241Am含量方面也有效(统计上与DTPA无显著差别),但能导致肾脏241Am蓄积,甚至略高于对照组.H-73-10虽有-些效果,但远不及DTPA.  相似文献   

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目的 比较56Fe17+12C6+重离子束与60Co γ射线对人淋巴细胞染色体畸变、周期、凋亡的影响。方法 56Fe17+12C6+重离子束和60Co γ射线分别照射人淋巴细胞系Peng-EBV,吸收剂量均为0、0.5和2.0 Gy,56Fe17+重离子束剂量率为0.26~0.55 Gy/min,12C6+重离子束剂量率为0.30~0.50 Gy/min,γ射线照射剂量率为0.75 Gy/min。研究不同射线对染色体细胞畸变率、“双+环”畸变率的影响。利用流式细胞仪检测细胞周期和细胞凋亡。结果 12C6+56Fe17+重离子与60Co γ射线照射后细胞畸变率与0 Gy相比,差异有统计学意义(χ2=12.08~322.97,P<0.05)。“双+环”畸变率与0 Gy相比,差异有统计学意义(χ2=4.06~205.37,P<0.05)。其中,12C6+重离子束诱导的细胞畸变率和“双+环”畸变率最高,其次是56Fe17+重离子束,而且二者均高于60Co γ射线。56Fe17+12C6+离子束与60Co γ射线均能诱导人淋巴细胞发生明显的G2期阻滞,差异有统计学意义(t=-80.9~0.17,P<0.05),12C6+重离子、γ射线及56Fe17+重离子诱导的G2期阻滞程度依次降低。56Fe17+12C6+离子束与60Co γ射线均能促进细胞凋亡,差异有统计学意义(t=-22.65~0.87,P<0.05),12C6+重离子、γ射线及56Fe17+重离子诱导的早期凋亡率依次降低。结论 56Fe17+12C6+离子束与60Co γ射线均能诱导人淋巴细胞发生明显的染色体畸变、G2期阻滞及细胞凋亡。12C6+离子束诱导的染色体畸变、周期阻滞和凋亡程度最高。56Fe17+12C6+离子束与γ射线的生物学效应与LET相关。  相似文献   

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目的 检测可食用野生蘑菇中人工放射性核素137Cs和天然放射性核素40K的含量及分布特点,计算野生蘑菇中放射性核素水平及其所致剂量。方法 采集了产自云南省芒市的18类33份可食用野生蘑菇样品,用实验室低本底高纯锗(HPGe)γ谱仪分析了其中放射性核素137Cs、40K的含量。结果 33份样品中,仅1份样品137Cs的含量在探测限之下,其余32份样品中均可检测出137Cs,比活度范围值为0.45~339.58 Bq/kg(干重),平均值25.47 Bq/kg(干重)。所有样品均检测出天然放射性核素40K,核素比活度最小值和最大值分别为453.4、1 882.6 Bq/kg(干重),平均值为815.1 Bq/kg(干重)。当去除只有1个样品数的蘑菇种类后,毛钉菇、美味牛肝菌、白牛肝菌、锈盖粉孢牛肝菌、香菇、茶褐牛肝菌6个种类蘑菇间137Cs含量差异有统计学意义(F=21.13,P<0.05),而40K含量差异无统计学意义。结论 6类不同蘑菇中137Cs含量不同,其中毛钉菇、香菇中人工放射性核素137Cs含量相对较高。但食入此类蘑菇对成人所致待积有效剂量极其微小,不会影响健康。  相似文献   

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目的 探讨重离子束照射对人淋巴细胞基因转录谱的改变。方法 人淋巴细胞Peng-EBV分别经0.1、0.5和2 Gy 56Fe17+12C6+重离子束照射后,提取各实验组细胞总RNA,利用Agilent人表达谱基因芯片进行基因转录谱的检测并筛选差异表达基因;对差异表达基因进行GO分析;利用KEGG数据库对差异表达基因进行通路分析。结果 Peng-EBV细胞系经56Fe17+12C6+重离子束照射后,0.1、0.5和2.0 Gy剂量组共同差异表达基因分别为101、199和229个。3个剂量组共同差异表达基因14个,其中,GPSM1、TSPYL5、WFDC2、LAD1等基因在两种离子束各剂量组呈现特征性差异表达。0.1和0.5 Gy剂量组涉及主要基因功能包括细胞粘连、胞外基质构建等,参与的显著性Pathway通路分别为3和6条,主要为细胞因子受体相互作用通路等。2 Gy剂量组主要基因功能包括细胞黏连、Rho蛋白信号转导调节等,参与的显著性Pathway通路3条,主要为p53信号通路等。结论 56Fe17+12C6+重离子束可诱导人淋巴细胞基因转录谱的改变,且不同剂量重离子可诱发不同的差异表达基因及通路。  相似文献   

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目的 提高222Rn与220Rn的累积测量水平,保证测量结果的准确性与可靠性。方法 采用中国疾病预防控制中心辐射防护与核安全医学所的氡课题组(以下简称本实验室)改进的LD-P型222Rn-220Rn分辨探测器参加日本放射线医学综合研究所(NIRS)组织的222Rn-220Rn累积探测器国际比对。将222Rn-220Rn分辨探测器寄往日本,在NIRS的222Rn室和220Rn室进行不同条件下的比对,暴露结束后再寄回本实验室进行蚀刻与分析,测量结果告知NIRS。最后NIRS将222Rn与220Rn暴露参考值回馈本实验室。结果 在高222Rn和低222Rn条件下,测量值与NIRS提供的参考值的相对百分偏差(RPD)分别为-12.0%、-11.8%;变异系数(COV)分别为3.0%、6.2%。在高220Rn和低220Rn条件下,测量值与NIRS提供的参考值的相对百分偏差(RPD)分别为-0.8%、-8.0%;变异系数(COV)分别为6.7%、4.5%。结论 本次比对LD-P型探测器222Rn与220Rn的测量结果均为NIRS规定的Ι级结果(PRD<10%),比对结果较好。  相似文献   

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目的 通过参加国际比对,提高222Rn和220Rn累积测量的水平,保证测量的质量。方法 将本实验室的LD-P型222Rn-220Rn探测器寄往日本放射线医学综合研究所(National Institute of Radiological Science,NIRS),参加222Rn-220Rn累积探测器的国际比对。222Rn比对在NIRS的标准222Rn室进行,按暴露量分低、中、高3个水平;220Rn比对在NIRS的220Rn室进行,也分低、中、高3个水平。暴露结束后将探测器寄回本实验室进行蚀刻、分析,然后把测量结果报给NIRS,最后NIRS将暴露的参考值反馈回本实验室。结果 LD-P探测器222Rn比对测量低、中、高3个暴露水平的测量值与参考值的相对偏差(RPD)分别为-13.8%、-14.4% 和-17.1%;220Rn比对测量低、中、高3个暴露水平的测量值与参考值的RPD分别为-14.4%、 8.9%和-3.2%。结论 本次比对LD-P探测器222Rn和220Rn的测量结果均在NIRS规定的RPD为20%的一级标准范围内。  相似文献   

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目的 监测与分析2017—2020年北京地区大气气溶胶中7Be和210Pb放射性活度浓度变化情况,为有效防治空气污染提供科学依据。方法 利用大流量空气气溶胶采样器(SnowWhite)采集气溶胶样品1 074份,其中春季、夏季、秋季和冬季分别采集275、266、262和271份。使用低本底高纯锗伽马谱仪(ORTEC)分析气溶胶样品中7Be和210Pb放射性活度浓度。结果 2017—2020年北京地区大气气溶胶中7Be放射性活度浓度的变化范围为0.56~14.84 mBq/m3,平均值为6.84 mBq/m3210Pb放射性活度浓度的变化范围为0.01~9.37 mBq/m3,平均值为3.19 mBq/m3。2017—2020年北京大气气溶胶7Be和210Pb放射性活度浓度在春、夏、秋、冬四季中差异均有统计学意义(F=32.66、93.93,P<0.05),其中7Be放射性活度浓度春季最高,秋季次之,夏季和冬季最低,210Pb放射性活度浓度由高到低分别为冬季、秋季、春季、夏季。结论 2017—2020年北京地区大气气溶胶中7Be和210Pb放射性活度浓度处于正常涨落水平范围内。  相似文献   

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本文叙述了环境水中低水平210Pb和210Po的分析方法。取水样40L以铅和铋作载体与碳酸钙共沉淀浓集210Pb和210Po, 在盐酸介质中, 210Po自发沉积于银片上, 用低本底计致器测量210Po的α活度将分离。210Po的沉积液放置三个月以上.再测定210Pb新生的。210Po的α活度, 从而计算210Pb的活度。  相似文献   

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目的 比较 3H-TdR与 125I-UdR掺入淋巴细胞的增殖效应。方法3H-TdR与 125I-UdR掺入法测定淋巴细胞和Daudi淋巴瘤细胞的增殖效应。结果 3H-TdR和 125I-UdR在正常淋巴细胞中的掺入率分别为20.95%±1.06%和1.00%±0.04%,在Daudi淋巴瘤细胞中的掺入率分别为29.94%±4.10%和6.02%±0.73%。 3H-TdR在细胞中的掺入率明显高于 125I-UdR;且 3H-TdR和 125I-UdR在淋巴瘤细胞中的掺入率高于正常淋巴细胞。结论 就淋巴细胞而言,作为示踪剂 125I-UdR不能替代 3H-TdR;但对于淋巴瘤细胞,能否代替 3H-TdR有待于进一步研究。  相似文献   

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The Knee injury and Osteoarthritis Outcome Score (KOOS) is a self-administered instrument measuring outcome after knee injury at impairment, disability, and handicap level in five subscales. Reliability, validity, and responsiveness of a Swedish version was assessed in 142 patients who underwent arthroscopy because of injury to the menisci, anterior cruciate ligament, or cartilage of the knee. The clinimetric properties were found to be good and comparable to the American version of the KOOS. Comparison to the Short Form-36 and the Lysholm knee scoring scale revealed expected correlations and construct validity. Item by item, symptoms and functional limitations were compared between diagnostic groups. High responsiveness was found three months after arthroscopic partial meniscectomy for all subscales but Activities of Daily Living.  相似文献   

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Objective To investigate endovascular treatment of traumatic direct carotid-cavernous fistulas (CCF) and their complications such as pseudoaneurysms. Methods: Over a five-year period, 22 patients with traumatic direct CCFs were treated endovascularly in our institution. Thirteen patients were treated once with the result of CCF occluded, 8 twice and 1 three times. Treatment modalities included balloon occlusion of the CCF, sacrifice of the ipsilateral internal carotid artery with detachable balloon, coll embolization of the cavernous sinus and secondary pseudoaneurysms, and covered-stem management of the pseudoaneurysms. Results All the direct CCFs were successfully managed endovascularly. Four patients developed a pseudoaneurysm after the occlusion of the CCF with an incidence of pseudoaneurysm formation of 18.2% (4/22). A total number of 8 patients experienced permanent occlusion of the ICA with a rate of ICA occlusion reaching 36.4% (8/22). Followed up through telephone consultation from 6 months to 5 years, all did well with no recurrence of CCF symptoms and signs. Conclusion Traumatic direct CCFs can be successfully managed with endovascular means. The pseudoaneurysms secondary to the occlusion of the CCFs can be occluded with stent-assisted coiling and implantation of covered stents.  相似文献   

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Acute limping may be the result of multiple pathologies in children. The differential diagnosis varies based on the age of the child. Irrespective of age, the initial imaging work-up includes AP and frog leg radiographs of the pelvis and ultrasound; MRI may sometimes be helpful. In children less than 3 years, infections and trauma are most frequent. MRI is the imaging modality of choice when osteomyelitis is clinically suspected. Between the ages of 3 and 10 years, transient synovitis of the hip and Legg-Calvé-Perthes disease are main considerations but infection, inflammation and focal bony lesions are also considered. In children over 10 years, slipped capital femoral epiphysis also is considered.  相似文献   

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Introduction Ankle sprains are the most common musculo-skeletal injury that occurs in athletes,particularly in sports that require jumping and landing on one foot such as soccer,and basketball(1-4).These injuries often result in significant time loss from participation,long-term disability,and have a major impact on health care costs and resources(5-8).  相似文献   

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KEY POINTS ·High-intensity interval training(HIT)is characterized by repeated sessions of relatively brief,intermittent exercise.often performed with an“a11 out”effort or at an intensity close to that which elicits peak oxygen uptake(i.e.,≥90%of VO2 peak).  相似文献   

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In response to the ENFSI and EDNAP groups’ call for new STR multiplexes for Europe, Promega® developed a suite of four new DNA profiling kits. This paper describes the developmental validation study performed on the PowerPlex® ESI 16 (European Standard Investigator 16) and the PowerPlex® ESI 17 Systems. The PowerPlex® ESI 16 System combines the 11 loci compatible with the UK National DNA Database®, contained within the AmpFlSTR® SGM Plus® PCR Amplification Kit, with five additional loci: D2S441, D10S1248, D22S1045, D1S1656 and D12S391. The multiplex was designed to reduce the amplicon size of the loci found in the AmpFlSTR® SGM Plus® kit. This design facilitates increased robustness and amplification success for the loci used in the national DNA databases created in many countries, when analyzing degraded DNA samples. The PowerPlex® ESI 17 System amplifies the same loci as the PowerPlex® ESI 16 System, but with the addition of a primer pair for the SE33 locus. Tests were designed to address the developmental validation guidelines issued by the Scientific Working Group on DNA Analysis Methods (SWGDAM), and those of the DNA Advisory Board (DAB). Samples processed include DNA mixtures, PCR reactions spiked with inhibitors, a sensitivity series, and 306 United Kingdom donor samples to determine concordance with data generated with the AmpFlSTR® SGM Plus® kit. Allele frequencies from 242 white Caucasian samples collected in the United Kingdom are also presented. The PowerPlex® ESI 16 and ESI 17 Systems are robust and sensitive tools, suitable for the analysis of forensic DNA samples. Full profiles were routinely observed with 62.5 pg of a fully heterozygous single source DNA template. This high level of sensitivity was found to impact on mixture analyses, where 54–86% of unique minor contributor alleles were routinely observed in a 1:19 mixture ratio. Improved sensitivity combined with the robustness afforded by smaller amplicons has substantially improved the quantity of data obtained from degraded samples, and the improved chemistry confers exceptional tolerance to high levels of laboratory prepared inhibitors.  相似文献   

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