γ射线与噪声对豚鼠听觉损伤的复合效应

研究了γ射线（２０Ｇｙ）与噪声（１０５ｄＢＡ，３０ｍｉｎ）一次联合作用及６次重复联合作用（每次γ射线０．６７Ｇｙ，噪声１００ｄＢＡ，３０ｍｉｎ），对豚鼠听觉损伤的复合效应。结果表明，先γ射线２０Ｇｙ照射后噪声暴露对听觉损伤的复合效应是协同的。６次重复联合作用时，先噪声暴露后照射组的听阈偏移小于先照射后噪声暴露组；前者的复合效应为拮抗，后者为相加。本文对γ射线与噪声对听觉损伤联合作用的机理作了初步探讨。     

Preoperative radiation therapy with sensitizers in the management of carcinoma of the rectum

There is enough evidence to show that adjuvant radiation therapy contributes to the management of patients with carcinoma of the rectum. In an effort to improve resectability and possibly survival rates, the use of chemosensitizers, combined with moderate doses of radiation used presurgically, was introduced for carcinomas larger than 5 cm in diameter requiring abdominoperineal resection. Based on our experience and that of others, it is believed that the method of administration of 5FU and mitomycin-C is an important factor in obtaining an increased therapeutic ratio. Because of the locoregional pattern of spread of rectal cancer, this adjuvant approach would appear suitable. A series of approximately 60 patients is discussed and the surgical findings and five-year survival is reported. Read at the Joint Meeting of the American Society of Colon and Rectal Surgeons with the Section of Colo-Proctology, Royal Society of Medicine, and the Section of Colonic and Rectal Surgery, Royal Australasian College of Surgeons, New Orleans, Louisiana, May 6 to 11, 1984.     

Large differences in education and training of radiographers in Europe and Central Asia: Results from an IAEA coordinated study

IntroductionEducation and training of radiographers is known to be diverse between countries and regions. Under an IAEA project, this work collected data on radiographer education for the Europe and Central Asia region with a particular focus on radiation protection gaps and potential actions.MethodsFollowing piloting, an electronic questionnaire was distributed to all national counterparts for the IAEA Technial Coopearation (TC) Europe region (n = 33 countries) and nominated national representatives. Contacts were additionally invited to a virtual workshop to discuss and rank common problems in education and training of radiographers and to propose potential solutions.ResultsResponses were received from 31 countries, including 14 from the European Union. Just over half of countries reported radiographer education being in higher education with 71% having program durations more than 3 years (range: 1 month-4 years). Programs included a spectrum of both clinical training and radiation protection hours with ten-fold variations noted across the region. Inclusion of core radiation protection topics within curricula varied similarly, as did radiographers’ clinical involvement in both justification and optimisation between countries. Workshop participants identified five common training problems, namely education availability, lack of standardisation, radiation protection course quality, teamwork problems and lack of equipment.ConclusionRadiographer education in the IAEA Europe region is heterogeneous with substantial differences in duration and quality of training programs between countries, which likely impact on quality of patient care delivered. Common problems have been identified and potential solutions proposed to focus quality improvement initiatives.Implications for practiceRadiographer education and training is diverse throughout the IAEA TC Europe region, with likely impacts on radiation protection practices applied. Clinical involvement of radiographers in justification and optimisation differs, potentially limiting adherence to radiation protection principles.     

European consensus on patient contact shielding

Patient contact shielding has been in use for many years in radiology departments in order to reduce the effects and risks of ionising radiation on certain organs. New technologies in projection imaging and CT scanning such as digital receptors and automatic exposure control (AEC) systems have reduced doses and improved image consistency. These changes and a greater understanding of both the benefits and the risks from the use of shielding have led to a review of shielding use in radiology. A number of professional bodies have already issued guidance in this regard. This paper represents the current consensus view of the main bodies involved in radiation safety and imaging in Europe: European Federation of Organisations for Medical Physics, European Federation of Radiographer Societies, European Society of Radiology, European Society of Paediatric Radiology, EuroSafe Imaging, European Radiation Dosimetry Group (EURADOS), and European Academy of DentoMaxilloFacial Radiology (EADMFR). It is based on the expert recommendations of the Gonad and Patient Shielding (GAPS) Group formed with the purpose of developing consensus in this area. The recommendations are intended to be clear and easy to use. They are intended as guidance, and they are developed using a multidisciplinary team approach. It is recognised that regulations, custom and practice vary widely on the use of patient shielding in Europe and it is hoped that these recommendations will inform a change management program that will benefit patients and staff.     

基于剂量预测的个性化放射治疗计划质量的定量评价方法

目的:提出一种基于剂量预测的放射治疗计划质量定量评价方法,并验证该方法的临床可行性和临床价值。方法:基于45例5年以上从业经验的物理师制定的直肠癌病例,训练3D U-Net网络。利用3D U-Net网络预测得到三维剂量分布后,基于剂量预测的剂量-体积直方图(DVH)指标,建立调强放射治疗(IMRT)直肠癌计划质量评估标...     

重庆市医用放射工作人员非癌发病探讨

目的 研究职业X射线暴露对放射工作人员非癌疾病的影响。方法 选取1980年普查四川省重庆市辖区内医用X射线工作者为调查对象。2020年,选取之前的91家医疗机构,分布在重庆市41个区县,其中三级医疗机构53家,运用前瞻性队列研究的方法,第5次随访1980年重庆市医用X射线放射工作人员(放射组)和同医院同时期非放射科工作人员(对照组)的个人信息、职业射线接触情况、疾病史等信息。分析该队列各系统疾病发病率、各系统疾病相对危险度(RR)及其95%置信区间。结果 该队列共计937人,共统计非癌疾病359例。放射组与对照组相比,其心血管系统、眼科和其他未分类疾病的相对危险度(RR)分别为1.50、2.03和2.64(χ²=5.97、3.97、4.25,P <0.05)。调整混杂因素的结果显示,女性放射组中心血管系统、眼科和消化系统等疾病发病率的RR普遍高于对照组(RR=2.33、2.59、7.55;χ²=7.28、4.17、8.64,P<0.05);在25~29岁参加工作人员中,放射组成员心血管系统、眼科等疾病发病率的RR普遍高于对照组(RR=2.26、5.07;χ²=8.22、4.91,P<0.05);累积剂量分组中,放射组与对照组比较,心血管系统、眼科和消化系统等疾病发病率的RR普遍较高(RR=1.86、2.91、3.59;χ²=9.83、8.21、5.58,P<0.05)。结论 受到长期职业照射的X射线工作者非癌发病危险增高,其中心血管系统、消化系统、眼科疾病等发病危险可能与这种职业照射有关。     

中子剂量测量及估算方法

随着科技的发展,中子在许多行业得到越来越广泛的应用,在医疗上应用最广泛的是硼中子俘获治疗.但在使用中子辐射的过程中,操作人员可能会受到中子辐射,因此中子剂量的测量和估算问题也就变得重要起来.目前,国内关于中子剂量的研究在有些方面还不是很深人,因此对中子剂量的测量和估算方法进行了归纳和阐述.     

血小板衍生生长因子及其受体与肿瘤细胞的辐射抗性

在多种恶性肿瘤中,存在血小板衍生生长因子(PDGF)及其受体(PDGFR)自分泌生长刺激的异常合成。PDGF是有效的有丝分裂原和化学驱动剂,PDGFR属于酪氨酸激酶受体,当PDGFR与PDGF结合后,活化-系列下游信号通路,并产生众多的生物学效应。研究表明,PDGF和PDGFR的信号通路与肿瘤细胞辐射抗性密切相关,其机制可能与促进细胞增殖、抑制凋亡、调控细胞周期阻滞有关。