γ线照射对大鼠胃酸分泌及胃泌素释放的影响

本实验观察了大鼠全身照射不同剂量(4～25Gy)及全腹部照射(10Gy)后胃酸分泌的变化并用RIA方法测定照射后胃窦及血清中胃泌素水平.结果表明,全身8～25Gy照射后第3天,腹部10Gy照射后1～6周,胃酸分泌明显抑制.主现表现为胃液中[H~+]分泌的抑制,致使照射后胃液酸度降低.10Gy以上剂量照射使胃泌素释放增加,表现为血清胃泌素明显升高,胃窦胃泌素明显减少,导致照射引起的"低胃酸、高胃泌素血症".这种表现与人的某些萎缩性胃炎或恶性贫血的状况相似.     

中医灸与人体穴位红外辐射光谱特性研究

本文通过锁相放大技术测到人体不到1cm^2面积的体表红外辐射光谱。通过对这些光谱的归一化处理后发现，不同人体和同一人体的不同穴位，尽管其红外辐射绝对光谱及强度相差很大，但归一化光谱都有相当的一致性与可比性。进一步将人体发射的平均归一化光谱与中医艾条灸、隔姜灸、隔蒜灸及隔附子饼灸点燃过程中的光谱比较发现，后面三种间隔灸与人体自发辐射的光谱有着惊人的一致性，而艾条灸等的光谱却相差甚远。     

核辐射对机体的影响

机体受到一定剂量核辐射后会出现多个器官结构和功能的改变.本文综述了机体受到低剂量核辐射后出现的免疫细胞数量和功能变化,包括淋巴细胞总数和部分亚群数量、淋巴细胞转化率、血清免疫球蛋白含量以及单核细胞功能等变化.同时还综述了核辐射对内分泌及遗传的影响.     

线扫描直接数字化X线摄影原理与应用

目的 探讨线扫描直接数字化X线摄影的工作原理与实用价值。方法 以多丝正比室线扫描X线摄影系统为基础，分析线扫描直接数字化X线摄影的适用性。结果 线扫描成像技术克服了散射线造成的干扰，且探测灵敏度和精密度分辨率高。结论 线扫描成像技术适合于除了动态摄影以外的各种数字X线摄影，对我国常规X线摄影逐步实现数字化开辟了美好的前景。     

血清内皮素-1作为早期放射性肺损伤标志物的探讨

目的:探讨内皮素-1(ET-1)作为一种早期放射性肺损伤诊断及病情变化的血清学标志物的可能性。方法:将190只雌性SD大鼠随机分为正常对照组(C组)和实验组,即:放射组(R组)、氟代他汀(Flu)干预组(Flu组)、维甲酸干预组(Ra组)及地塞米松(Dex)干预组(Dex组)。实验组大鼠麻醉固定后,用直线加速器全胸照射15Gy1次,剂量率为2Gy/min,距离为1m。从照射后次日开始,Flu组经胃灌服Flu(20mg·kg-1·d-1),Ra组灌服Ra(20mg·kg-1·d-1),Dex组灌服Dex(3.33mg·kg-1·d-1),C及R组均灌服等量的生理盐水。各组分别于照射后5、15、30、60d,将大鼠分批断头或经心内穿刺取血,分离血清;同时切取肺组织,用放射测定法(RIA)分别测定ET1,层黏连蛋白(LN)及透明质酸(HA)的水平;同时观察肺部的病理变化。结果:与C组相比较,R组大鼠血清ET-1的水平于照射后第5天开始升高(P<0.05),尔后随着放射性肺损伤的加重逐渐升高,于照射后60d检测达高峰。R组大鼠血清LN的水平于照射后30d开始升高,HA于照射后60d开始升高。R组大鼠血清ET-1水平的升高明显早于其他各组,且同放射性肺损伤的病理变化的程度相关。结论:血清ET-1可作为放射性肺损伤早期诊断及动态监测病情变化的一种标志物。     

PET脑显像及其他显像技术在放射性脑损伤诊断的对比性研究

目的 探讨^18F－脱氧葡萄糖（FDG）正电子发射型计算机断层显影（PET）脑显像和其他医学影像方法对早期诊断放射性脑损伤的价值，以达到预防、减少脑放射损伤的目的。方法 静脉注射^18F-FDG后行脑显像，获得横断面、冠状面、矢状面断层显像。所有病人均进行CT检查。结果 20例正常人脑PET显像图像可见大脑皮质各叶、基底神经节、丘脑及小脑放射性分布均匀对称。12例完成头颈部恶性肿瘤放疗后有临床症状者均检出不同程度局灶性脑组织葡萄糖代谢下降，显像阳性率100％；其中10例鼻咽癌放疗后PET结果提示放射脑损伤病灶共23处，最常见于颞叶病灶13处、脑干4处、小脑4处以及顶叶2处。2例脑胶质细胞瘤放疗病人，PET结果提示病灶：顶叶2处、颞叶1处、枕叶1处。12例放疗后病人CT检查仅10例提示放射性脑损伤。结论 PET脑显像能准确、早期诊断脑放射损伤，是头颈部恶性肿瘤肿瘤放疗后的非常重要的监测手段。     

Case of postradiation osteosarcoma with a short latency period of 3 years

Osteosarcoma is one of the neoplasms that may occur following exposure to radiation. A case of osteosarcoma arising in the craniofacial bone with a short latency period of 3 years after radiotherapy for maxillary squamous cell carcinoma is described. A 64-year-old-man underwent right partial maxillectomy and chemoradiotherapy due to squamous cell carcinoma of his right maxillary sinus. Histologically, the tumor was composed of moderately differentiated squamous cell carcinoma with a component of spindle cell carcinoma. Three years later, osteosarcoma developed in the craniofacial bone within the irradiation field of the first tumor. Detailed histological examination demonstrated that there was no component of osteosarcoma in the first tumor or squamous cell carcinoma in the second tumor. Radiation-induced osteosarcoma usually occurs after a long latency period of more than 10 years after the radiotherapy. In this case, osteosarcoma was possibly a radiation-induced osteosarcoma with a short latency period of 3 years.     

IL-2对辐射损伤后小肠上皮细胞生长影响的实验研究

目的: 观察电离辐射对体外培养的IEC -6细胞株生长的影响及IL- 2对其损伤后增殖和恢复的作用, 并进一步探讨肠黏膜免疫与肠上皮辐射损伤及修复的关系。方法: 用 4、8、12Gy的γ射线照射IEC- 6细胞株, 并于照后 3、6、9、12h及 1、2、3d, 用MTT比色法、光镜、电镜、DNA凝胶电泳和流式细胞术等, 检测受照射后IEC- 6细胞的增殖活力、形态和死亡方式的改变; 用不同浓度IL 2 ( 25×103、5×104、1×105U/L)处理 8Gyγ射线照射的IEC 6细胞, 并于照射后 3、6、9、12、24h, 采用MTT比色法检测其增殖活力的变化。结果: 在 0~12Gy的范围内, IEC 6细胞的增殖活力随γ射线照射剂量的增加而降低。8. 0γ射线照后 24h, 凋亡的IEC- 6细胞明显增多, DNA凝胶电泳显示有梯状带形成。IL- 2可促进照射后的IEC- 6细胞增殖且呈一定的剂量 效应关系, 尤以1×105U/L组的作用更明显。结论: 在一定剂量范围内, γ射线照射可降低IEC 6细胞增殖活力, 且存在剂量 效应关系;可导致IEC 6细胞发生凋亡。IL- 2可促进受照射的IEC- 6细胞增殖, 增强其抗辐射的作用。     

Chromosome neighborhood composition determines translocation outcomes after exposure to high-dose radiation in primary cells

Radiation exposure is an occupational hazard for military personnel, some health care professionals, airport security screeners, and medical patients, with some individuals at risk for acute, high-dose exposures. Therefore, the biological effects of radiation, especially the potential for chromosome damage, are major occupational and health concerns. However, the biophysical mechanisms of chromosome instability subsequent to radiation-induced DNA damage are poorly understood. It is clear that interphase chromosomes occupy discrete structural and functional subnuclear domains, termed chromosome territories (CT), which may be organized into ‘neighborhoods’ comprising groups of specific CTs. We directly evaluated the relationship between chromosome positioning, neighborhood composition, and translocation partner choice in primary lymphocytes, using a cell-based system in which we could induce multiple, concentrated DNA breaks via high-dose irradiation. We critically evaluated mis-rejoining profiles and tested whether breaks occurring nearby were more likely to fuse than breaks occurring at a distance. We show that CT neighborhoods comprise heterologous chromosomes, within which inter-CT distances directly relate to translocation partner choice. These findings demonstrate that interphase chromosome arrangement is a principal factor in genomic instability outcomes in primary lymphocytes, providing a structural context for understanding the biological effects of radiation exposure, and the molecular etiology of tumor-specific translocation patterns.     

Effect of irradiation on the formation of hemodynamic pulmonary edema

Experiments on 233 albino rats showed that large doses of ionizing radiation, causing marked leukopenia, increased the resistance of animals to pulmonary edema under the influence of adrenalin. This effect was particularly marked on the fourth day after irradiation. Relatively small doses (under 100R) and also irradiation separately of the head, thorax, or abdomen, on the other hand facilitated the development of pulmonary edema.Department of Pathological Physiology, Yaroslavl' Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR N. A. Fedorov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 86, No. 9, pp. 280–282, September, 1978.