北京市乡镇级集中式饮用水总放射性监测分析

目的 调查2018—2019年北京市乡镇级集中式饮用水中的总放射性水平及分布特点,以便更好的开展水质放射性监测和评价工作。方法 抽查北京市12个行政区共215 件乡镇地下饮用水样品,依据EJ/T 1075—1998《水中总α放射性浓度的测定 厚样法》、EJ/T 900—1994《水中总β放射性测定 蒸发法》进行监测分析。结果 2018—2019年北京市乡镇级集中式饮用水总α放射性水平为0.050（0.052）Bq/L,范围为（0.001～0.210）Bq/L,总β放射性水平为0.048（0.038）Bq/L,范围为（0.002～0.261）Bq/L,所有样品的总放射性水平皆低于我国生活饮用水卫生标准的放射性指标指导值。所有行政区地下水总α、总β放射性水平在2018—2019年分布差异无统计学意义（P > 0.05）;同一时期不同行政区的总α、总β放射性水平分布差异有统计学意义（P < 0.05）,潮白河水系的密云、怀柔和顺义较高。结论 北京市乡镇饮用水中放射性本底分布水平,处于正常范围。     

高传能线密度辐射对人眼晶状体的危害

眼晶状体是人体对辐射最敏感的组织之一,电离辐射的生物效应因其传能线密度（linear energy transfer, LET）的不同而不同,同等吸收剂量条件下,高LET辐射生物效应比低LET辐射更强,尽管目前辐射对眼晶状体的影响这一领域已经有了较多研究,但对于高LET对眼晶状体的影响知之甚少。本文简述人眼晶状体剂量限值的历史变化情况,综述各种高LET粒子的生物学实验,调查高LET辐射眼晶状体的流行病学,简要分析高原白内障高患病率的原因,并初步讨论未来研究高LET需要考虑的因素,旨在为国内今后开展高LET辐射对人眼晶状体的研究提供有价值的信息。     

A 2-year review of recent Nuclear Regulatory Commission events: What errors occur in the modern brachytherapy era?

PurposeTo perform a retrospective analysis of recently reported brachytherapy errors to the Nuclear Regulatory Commission and to compare with historical trends.MethodsAll events reported in the 2-year period from January 1, 2009 to December 31, 2010 were categorized and analyzed. The 4 main areas of dose delivery were Gamma Knife radiosurgery, therapeutic radiopharmaceutical administration, high-dose-rate brachytherapy, and low-dose-rate brachytherapy. The different types of errors were wrong site, wrong dose, unintended exposure, lost or leaking source, or other. The causes of events were specified as the following: communication errors, equipment malfunction, human error, lack of training, or miscellaneous.ResultsOne hundred and forty-seven events were found in the 2-year period. This error reporting rate far surpasses previous reports. The greatest number of events reported was for low-dose-rate brachytherapy, and the most common cause of error was human error. Wrong dose was the error that occurred most often, followed by wrong site.ConclusionsVery simple treatment errors, such as wrong patient, or wrong side of patient treated, are still occurring. Newer, complex deliveries such as high-dose-rate partial breast irradiation and low-dose-rate prostate brachytherapy also had a large number of events reported in this sampling. This report can help institutions establish needs for quality assessment and quality control processes.     

某大学放射性同位素32P应用项目辐射环境监测与评价

目的 评价某大学放射性同位素³²P应用项目对周围环境的辐射影响。方法 依据国家相关标准规定的限值及监测方法作为评价标准和监测手段。结果 该放射性同位素³²P应用项目γ空气吸收剂量率为62.8~108 nGy/h，处于该市天然本底水平范围内。该³²P应用项目工作间，控制区β表面污染监测结果为0.057~0.235 Bq/cm²，符合《电离辐射防护与辐射源安全基本标准》（GB 18871-2002）。该³²P应用项目衰变池水中总α放射性为0.039 Bq/L，低于《医疗机构水污染物排放标准》（GB 18466-2005）中规定的1 Bq/L的标准限值；总β放射性为9.37 Bq/L，低于《医疗机构水污染物排放标准》（GB 18466-2005）中规定的10 Bq/L的标准限值。结论 该项目对职业工作人员和公众是安全的，对周围环境产生的影响较小。     

Preparation and first biological evaluation of novel Re-188/Tc-99m peptide conjugates with substance-P

IntroductionNew ¹⁸⁸Re and ^99mTc peptide conjugates with substance- P (SP) were prepared and biologically evaluated. The radiopharmaceuticals have been labelled with the [M≡N]²⁺ (M=^99mTc, ¹⁸⁸Re) core using a combination of π-donor tridentate and π-acceptor monodentate ancillary ligands.MethodsThe new radiopharmaceuticals have been prepared through a two-step reaction by simultaneous addition of the tridentate and monodentate ligands to a vial containing a preformed [M≡N]²⁺ core. The tridentate ligand was formed by linking two cysteine residues to the terminal arginine of the undecapeptide SP, whereas the monodentate ligand was a tertiary phosphine. The preparation of the corresponding Re-188 derivative required developing a more complex chemical procedure to obtain the [Re≡N]²⁺ core in satisfactory yields. Characterization of the resulting products was obtained by chromatographic methods. Biological evaluation was performed for both Tc-99m and Re-188 derivatives by in-vitro studies on isolated cells expressing NK1-receptors. In-vivo imaging in mice was carried out using a small-animal YAP(S)PET tomograph.ConclusionNew Tc-99m and Re-188 peptide radiopharmaceuticals with SP have been prepared in high-yield and with high-specific activity. Both Tc-99m and Re-188 peptide radioconjugates exhibit high affinity for NK1 receptors, thus giving further evidence to the empirical rule that structurally related Tc-99m and Re-188 radiopharmaceuticals exhibit identical biological properties.     

ACR CT Accreditation Program and the Lung Cancer Screening Program Designation

The ACR recognizes that low-dose CT for lung cancer screening has the potential to significantly reduce mortality from lung cancer in the appropriate high-risk population. The ACR supports the recommendations of the US Preventive Services Task Force and the National Comprehensive Cancer Network for screening patients. To be effective, lung cancer screening should be performed at sites providing high-quality low-dose CT examinations overseen and interpreted by qualified physicians using a structured reporting and management system. The ACR has developed a set of tools necessary for radiologists to take the lead on the front lines of lung cancer screening. The ACR Lung Cancer Screening Center designation is built upon the ACR CT accreditation program and requires use of Lung-RADS or a similar structured reporting and management system. This designation provides patients and referring providers with the assurance that they will receive high-quality screening with appropriate follow-up care.