Radiation Hazards Control in Survival Operations in the Event of a Nuclear War

The concepts of radiation protection in survival operations are explained, and procedures devised to control radiation hazards for the protection of the population and maintenance of the operating efficiency of survival operations personnel are presented.

Radiation protection is a command function. The medical responsibility is to provide advice on the probable effects of radiation exposure in the light of existing knowledge of these effects in man.

The major hazard is that of external exposure to penetrating gamma radiation. Radiation exposure guides indicate that persons may be exposed to not more than 100 r whole body radiation in a six-week period, or 200 r whole body radiation in a period in excess of six weeks, without loss of operational efficiency. Beta radiation from fallout deposited on skin or clothing may produce burns, but these injuries will not be incapacitating and can be controlled by simple procedures.

The internal hazard is mainly from ingestion of food or water contaminated with radioactive material. For protection, only canned or packaged foods and water from covered or deep wells are consumed during the early days after a nuclear attack.

     

医院PET-CT中心18F正电子放射性药物生产及使用中工作人员的辐射剂量监测

目的 研究以18F-脱氧葡萄糖（18F-FDG）为代表的正电子放射性药物在生产和使用过程中医务人员的辐射剂量,为临床辐射防护提供参考数据。方法 测量18例工作人员在制药、质控、分装、传送、注射及摆位的工作流程中手、胸部的当量剂量率（d）及操作时间（t）,并结合不同年检查工作量（w）估算各工作场所工作人员的年受照剂量。结果 估算得到年检查工作量为1000、4000、7000和10000例时,不同工作环节工作人员的累计年剂量为质控0.27mSv,分装0.02～0.20mSv,传送0.06～0.58mSv,注射2.49～24.9 mSv,摆位1.19～11.91mSv。结论 在现有防护设施和操作条件下, 分装和注射是接受剂量较高的工作环节。当年检查工作量在4000例以上时,从事分装工作的人员手部受照剂量超过国家标准关于职业个人年剂量限值的规定;当年检查工作量在10000例时,从事注射的人员年有效剂量亦超过相关国家标准的规定。     

Radiation Protection in Canada: Part VII. The Role of Industrial Hygiene in the Field of Radiation Protection

The main emphasis of a provincial radiation protection program is on ionizing radiation produced by machines, although assistance is given to the Federal Radiation Protection Division in its program relating to radioactive substances. The basis for the Saskatchewan program of radiation protection is the Radiological Health Act 1961. An important provision of the Act is annual registration of radiation equipment. The design of the registration form encourages a “do-it-yourself” radiation and electrical safety inspection.

Installations are inspected every two years by a radiation health officer. Two hundred and twenty-one deficiencies were found during inspection of 224 items of radiation equipment, the commonest being failure to use personal film badges. Insufficient filtration of the beam, inadequate limitation of the beam, and unnecessary exposure of operators were other common faults.

Physicians have a responsibility to weigh the potential advantages against the hazards when requesting radiographic or fluoroscopic procedures.

     

放射事故外照射对人体剂量分布的研究

目的 研究各种放射照射条件下人体内剂量分布及剂理学参数的特点。方法 考虑各种参数在计算中的影响后,用组织－空气比方法计算得出人体内的剂量分布,进而计算出各剂量学参数,并利用组织等效仿真人体模型进行了实验验证。结果 人体内剂量分布越均匀,干细胞剂量与平均剂理直接近;干细胞剂理可大于平均剂量;全身干细胞剂理计算值与实验值之差小于５％。理论 所用计算方法与程度是可靠的。该计算程序已在实际事故处理中得到了     

阳江高本底放射地区1979～1995年恶性肿瘤死亡调查分析

目的 探索平均年有效剂量为６．４ｍＳｖ的广东省阳江地区天然高本底放射的致癌危险,方法 对１９７９￣１９８６年的恶性肿瘤死亡资料通过前瞻性调查从一个动脉队列来收集,对１９８７￣１９９５年资料通过回顾性调查和（或）前瞻性调查从一个固定人群队列获得。恶性肿瘤死亡资料现场调查分队列成员追踪和死因确认两步骤。个人累积剂量估算包括内照射和外照射。按以坟平均的居民年外照射剂量水平,将研究人群分为４个剂量组进行比     

产前糖皮质激素应用对胎鼠脑发育的影响

目的:探讨产前应用不同剂量糖皮质激素(antenatal corticorsteriod theray,ACT)对胎鼠脑发育的影响.方法:对怀孕第17天的SD大鼠每天肌注地塞米松0.8 mg/kg,肌注1次的为1剂组、肌注3次的为3剂组和肌注4次的为4剂组,没有使用地塞米松的为对照组.对各组孕鼠所生的胎鼠,分别于生后第1、第7和第14天测量体重、全脑重量、脑细胞凋亡情况并与对照组作比较.结果:实验组胎鼠的体重、全脑重量较对照组明显下降,尤以4剂组最明显;脑细胞凋亡数3剂组、4剂组与对照组在第1天有差别,第7天和第14天差别减弱.结论:ACT对胎鼠的体重、全脑重量、脑细胞凋亡等产生不良影响,剂量越大副作用越明显.     

回旋加速器运行期间的环境监测及辐射影响分析

目的：通过监测回旋加速器周围环境辐射剂量水平,评价其对环境、公众及相关工作人员的辐射安全性。方法：根据污染因子分析,用专用的辐射剂量监测仪器对回旋加速器开机状态下,机房外围环境进行γ、中子辐射剂量率监测。结果：在开机状态下回旋加速器机房门外周围环境γ辐射剂量率为(27~53) ×10-8Gy/h,中子辐射剂量为(0.009~0.019)uSv/h。结论：回旋加速器在开机状态下,不会对周围环境产生辐射影响,工作人员受到的年辐射剂量也远小于国家规定的个人年辐射剂量限制。     

^131I标记抗肝癌单克隆抗体HAb18生物动力学及器官吸收剂量

考察＾１３１Ｉ－ＨＡｂ１８在正常人体内的生物学分布和器官辐射吸收剂量、为临床用提供必需的依据。一健康志愿者静脉给药后没时间用γ相机行全身及局部并采取血样本及留全尿，按医学内照射剂量纲要计算器官吸收剂量。     

低剂量电离辐射对松果腺细胞凋亡的影响

目的：通过低剂量辐射兴奋效应的动物模型,进一步探讨低剂量X射线全身照射对小鼠松果腺细胞凋亡的影响。方法：采用0．075Gy X射线全身照射后不同时间间隔取松果腺,采用流式细胞术（FCM）检测照射后不同时间松果腺细胞凋亡百分率的时程变化。结果：低剂量电离辐射全身照射12h、24h、48h后松果腺细胞凋亡百分率降低（P〈0．01）。结论：低剂量辐射可抑制松果腺细胞的凋亡。     

Multiple fluoroscopy of the chest: carcinogenicity for the female breast and implications for breast cancer screening programs.

The risk of radiation carcinogenesis has been established for breast tissue from experience with total body irradiation and multiple fluoroscopy of the chest with the patient prone. The doubling dose has been estimated to lie between 20 and 50 rads. Before undertaking radiologic screening programs for breast cancer, therefore, it is necessary to determine whether exposures below this range are safe. Of 792 women who had had tuberculosis and were followed for a minimum of 20 years, 451 had had multiple fluoroscopy while supine; 341 had not had fluoroscopy. The first group received a total radiation dose to the breast averaging 17 rads (141.5 fluoroscopies); the incidence of breast cancer in this group was not increased. Had fluoroscopy been performed with the patient prone the total radiation dose would have averaged 308 rads. The difference is thought to explain the increased incidence of breast cancer attributable to fluoroscopy given with the patient prone. Mid-breast exposure with mammography or xeroradiography varies between 3 and 6 rads. Repetitive screening would, therefore, appear safe provided total exposure did not exceed 20 rads. With this restriction there would appear to be no reason to curtail screening of women for breast cancer.     

茶儿茶素对小鼠的辐射防护作用

目的探讨儿茶素对小鼠的辐射防护作用。方法采用6MVX直线加速器一次性全身照射小鼠,儿茶素加照射组以200mg/kg.d儿茶素灌服动物10d后施行照射。比较两组小鼠体质量变化、外周血白细胞总数、平均存活时间及30d生存率。结果儿茶素加照射组小鼠体质量减轻低于照射组,平均生存时间明显长于照射组,30d存活率比对照组明显升高,而且儿茶素能加快单纯受照射小鼠外周血白细胞的恢复。结论儿茶素对受照射小鼠有明显的辐射防护作用。     

Objective evaluation of ERCP procedures: a simple grading scale for evaluating technical difficulty

Background and objective: Endoscopic retrograde cholangiopancreatography (ERCP) is a technically demanding endoscopic procedure that varies from a simple diagnostic to a highly complex therapeutic procedure. Simple outcome measures such as success and complication rates do not reflect the competence of the operator or endoscopy unit, as case mix is not taken into account. A grading scale to assess the technical difficulty of ERCP can improve the objectivity of outcome data. Methods: A I to IV technical difficulty grading scale was constructed and applied prospectively to all ERCPs over a 12 month period at a single centre. The procedures were performed by two senior trainees and two experienced consultants (trainers). The grading scale was validated for construct validity and inter-rater reliability at the end of the study using the χ² test and κ statistics. Results: There were 305 ERCPs in 259 patients over the 12 months study period (males: 112, females: 147, age range 17–97, mean 70.3 years). There was overall success in 244 (80%) procedures with complications in 13 (4%): bleeding in five (1.6%), cholangitis in one (0.3%), pancreatitis in five (1.6%), and perforation in two (0.7%). Success rate was highest for grade I, 49/55 (89%), compared with grade IV procedures, 8/11 (73%). There was a significant linear trend towards a lower success rate from grade I to IV (p=0.021) for trainees, but not for trainers. Complications were low in grade I, II, and III procedures, 12/295(4%), compared with grade IV procedures, 1/11(9%). The inter-rater reliability for the grading scale was good with a substantial agreement between the raters (κ=0.68, p<0.001). Conclusion: Success and complications of ERCP by trainees are influenced by the technical difficulty of the procedure. Outcome data incorporating a grading scale can give accurate information when auditing the qualitative outcomes. This can provide a platform for structured objective evaluation.     

乳腺癌保留乳房术后应用图像引导放射治疗效果探讨

目的:评价乳腺癌保留乳房手术(保乳术)后调强放射治疗剂量学优势,评估图像引导技术在乳腺癌保乳术后调强放射治疗的摆位误差和计划靶体积边界。方法:6例早期乳腺癌接受保乳手术的患者,实施全乳腺图像引导调强放疗50 Gy,瘤床电子线加量10 Gy。评价乳腺靶区的剂量分布均匀性和周围正常组织的照射剂量和体积,观察临床毒性反应,统计摆位误差。结果:靶区剂量均匀,正常组织受量在允许范围内,摆位误差左右方向≤0.3 cm,其他方向≤0.5 cm。结论:乳腺癌保乳术后全乳腺调强靶区剂量均匀性好,正常组织受量小,临床毒性反应小,摆位重复性差,采用锥形束CT图像引导放疗可减少摆位误差。     

电离辐射对小鼠淋巴结皮质细胞凋亡的影响

目的：研究不同剂量Ｘ射线全身照射对小鼠淋巴结皮质细胞凋亡的影响。方法：采用原位末端标记（ＴＵＮＥＬ）法检测高、低剂量电离辐射后肠系膜淋巴结皮质中细胞凋亡情况。结果：淋巴结皮质的不同区域对高、低剂量电离辐射的敏感性均不同。结论：低剂量辐射所致的小结间区及深皮质区凋亡细胞数减少,是低水平辐射兴奋效应的一种表现。     

Radiation Protection in Canada: Part IV Factors of Importance in Minimizing Radiation Exposure of Patients, Operators and Others Involved in Diagnostic and Therapeutic Radiology

Factors that may reduce the dose of radiation, from diagnostic and therapeutic x-ray procedures, to the patient and to the occupational and non-occupational worker are outlined. Suitable basic radiation measuring apparatus is described. It is recommended that, in diagnostic radiography, relatively high kilovoltage, proper cones, collimation and adequate filtration be used. Some specific recommendations are made concerning fluoroscopic, photoroentgen and portable x-ray examinations. Film monitoring of personnel is advisable. Examples are given of protective devices to lessen the dosage to the occupational worker. It is the responsibility of the radiologist or physician in charge to ensure that the x-ray equipment is safe to operate and the radiation dose to the patient is kept to a minimum. The roentgen output for all radiographic examinations should be known by the responsible user.     

顽固性癫痫的低剂量放射外科治疗

目的 利用PET致痫灶定位，研究放射外科治疗顽固性癫痫的靶区设定原则，确定最佳周边剂量范围，方法 176例病人经^18F-FDGPET显像致痫灶定位后，行直线加速器放射外科治疗，按所采用周边剂量的不同（9-11Gy;11-13Gy;≥13Gy)分为三组，随访3-16个月，观察各组不同随访时间的癫痫发作频率变化。评价治疗效果。结果 每组病例在3个时间段均可观察到癫痫发作频率较治疗前明显降低。与放射治疗前相比具有显著性差异；在各时间段不同病例组间比较无显著性差异。治疗后疗效Ⅰ-Ⅱ级和Ⅲ-Ⅳ级的病人分别占46.9%和41.5%。所有病例均未见明显并发症发生。结论 PET引导下的低剂量放射外科治疗顽固性癫痫具有较高的有效率，无明显并发症，是一种有效的癫痫微侵外科治疗新方法；采用9-11Gy的周边剂量照射PET提示的致痫灶和可疑致痫灶即可取得良好效果。     

螺旋断层放疗全身照射剂量的分布评价及不良反应

目的：观察螺旋断层放疗系统进行骨髓移植前全身照射的剂量评价及急性毒副反应。方法：2011年8月至2012年8月采用螺旋断层放疗对6例白血病患者在异基因造血干细胞移植预处理期间实施全身照射,其中4例为急性淋巴细胞白血病（ ALL）、1例为急性混合细胞白血病（ MAL）、1例为T细胞性淋巴细胞白血病/T淋巴母细胞性淋巴瘤（ T-LBL）。毒副反应的评价按CTCAE v3.0。结果：全部患者按计划完成全身照射。截至2013年12月1日,2例生存、4例死亡。急性毒副反应：腹泻4例,口腔黏膜炎4例,恶心、呕吐6例,未发现放射性肺炎和皮肤毒性。结论：应用螺旋断层放疗技术进行全身照射的剂量分布评价直观简便。肺的剂量限制对胸部和上腹部器官的剂量分布有明显影响。胃肠道3级或3级以上副反应常见。     

Occupational Radiation Exposure and Changes in Thyroid Hormones in a Cohort of Chinese Medical Radiation Workers

Objective This study aimed to evaluate the association between occupational radiation exposure and changes in thyroid hormone levels among medical radiation workers. Methods This retrospective cohort study included 2,946 radiation workers from 20 Guangzhou hospitals. Data on general characteristics, participant radiation dosimetry, and thyroid function test results [thyroid-stimulating hormone (TSH), triiodothyronine (T3), and thyroid hormone (T4)] were extracted from dosimetry and medical records. The generalized estimating equation was used to evaluate the trend of changes in thyroid hormone levels over time and was adjusted for age, gender, and occupation. Results The average annual effective dose was very low and showed a general downward trend. During the follow-up period, changes in T3 and T4 levels among radiation workers were –0.015 [95％confidence interval (CI) –0.018 to –0.012] nmol/L per year and –2.294 (95％ CI –2.426 to –2.162) nmol/L per year, respectively. Thyroid hormone levels were significantly different between males and females. T3 levels in the group of upper quartile of dose were significantly higher than in the lower quartile group (P = 0.006). No significant decreased trend in thyroid hormone levels was observed with increasing average effective doses. Conclusion Thyroid hormone secretion might be affected even in low-dose radiation exposure environments.     

低剂量电离辐射对小鼠脾脏细胞凋亡的影响

目的：研究不同剂量 Ｘ 射线全身照射对小鼠脾脏细胞凋亡的影响。方法：采用透射电镜术定性及原位末端标记（ Ｔ Ｕ Ｎ Ｅ Ｌ）术半定量地观察了电离辐射对小鼠脾脏细胞凋亡影响的时程变化及量效关系。结果：透射电镜观察到２ Ｇｙ Ｘ 射线全身照射后脾脏出现较多典型的凋亡的淋巴细胞,００７５ Ｇｙ 照射后细胞超微结构无显著变化。 Ｔ Ｕ Ｎ Ｅ Ｌ 法观察到高剂量电离辐射使脾细胞凋亡增多,而低剂量电离辐射则使脾细胞凋亡减少,剂量效应关系曲线呈“ Ｊ”型。结论：不同剂量电离辐射对脾细胞凋亡的影响不同;低剂量电离辐射使脾脏细胞凋亡减少为辐射兴奋效应的一种表现。     

Analysis of Data from a System of Assessment of the Gonadal Radiation Dose During Radiographic Procedures

The radiation hazard, if any, from diagnostic x-ray examinations was assessed in a study divided into three phases: (1) the gathering of data to allow estimation of the total gonadal dose received by each patient; (2) the accumulation of the individual and accumulative gonadal-dose totals on a large group of patients; (3) the examination and follow-up of patients who had received a substantial gonadal dose to determine any relationship between small recurring doses of ionizing radiation and various indices of somatic and genetic damage.

The mean gonadal dose received by females was much higher than that received by males—1012 mr. as compared to 310 mr. Of 7021 individuals in this study, only 428 (6.1%) received 2 r. or more during the three-year test period. No definite conclusions as to radiation hazard could be made. A system, however, has been developed which, if continued, could eventually produce this basic information.