Upregulation of VEGF and FGF2 in normal rat brain after experimental intraoperative radiation therapy

The expression of vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF)2 in the irradiated brain was examined to test how a single high dose radiation, similar to that used for intraoperative radiation therapy given to the normal cerebrum, can affect the vascular endothelium. After a burr hole trephination in the rat skull, the cerebral hemisphere was exposed to a single 10 Gy dose of gamma rays, and the radiation effect was assessed at 1, 2, 4, 6, and 8 weeks after irradiation. Histological changes, such as reactive gliosis, inflammation, vascular proliferation and necrosis, were correlated with the duration after irradiation. Significant VEGF and FGF2 expression in the 2- and 8-week were detected by enzyme-linked immunosorbent assay quantification in the radiation group. Immunohistochemical study for VEGF was done and the number of positive cells gradually increased over time, compared with the sham operation group. In conclusion, the radiation injuries consisted of radiation necrosis associated with the expression of VEGF and FGF2. These findings indicate that VEGF and FGF2 may play a role in the radiation injuries after intraoperative single high-dose irradiation.     

近场射频辐射条件下大白鼠共振吸收频率的研究

在Ｅ极化、辐射电平１ｍｗ／ｃｍ２条件下，在４０．６８ＭＨｚ～４ＧＨｚ频段内６个频率点上，利用红外热图术观察了６０只Ｗｉｓｔａｒ成年大白鼠，连续辐射１ｈ后，体表及各部位体表温度变化。结果表明，体表温度与肛温变化有很好的一致性，并在１．５ＧＨｚ有最大值。它表明在该频率下，实验鼠吸收射频能量最大，表现出明显的谐振吸引特性。     

Radiation therapy for pancreatic cancer: eleven year experience at the JCRT

Radiation therapy (XRT) for 41 patients with unresectable pancreatic cancer resulted in a median survival of 7.0 months. There was no difference in median survival for patients receiving external beam alone (3500 to 5600 cGy) (n = 28), intraoperative (IORT) boost plus external beam (5040 to 6750 cGy) (n = 9), or a gold-198 implant +/- external beam radiation (n = 4). A pilot study using orthovoltage IORT boost indicates no acute toxicity with doses of 1250 to 1750 cGy. Serious late damage has not been observed in any patients followed to 2 years. Local recurrence in patients treated post-operatively after "radical" surgery occurred in one of 10 (10%). This adjuvant treatment is safe and appears to improve local control rates compared to historical data, but survival is still poor. The median survival for the post-operative group is 10 months; three patients are alive without disease 8 months to 8.3 years after treatment.     

The influence of radiation therapy on T-lymphocyte subpopulations defined by monoclonal antibodies

We studied the influence of radiation therapy on lymphocyte subpopulations in 17 patients undergoing adjuvant radiation therapy for primary breast cancer, and eight patients receiving brachytherapy and external beam irradiation for primary cancer of the uterus. Radiation therapy reduced B- and T-lymphocytes in proportion to the total lymphocyte population so that their percentages remained unchanged. Determination of helper and suppressor T-lymphocytes before, during and 6 months after completion of radiotherapy revealed that in both groups of patients suppressor T-lymphocytes were more resistant to and recovered faster after radiotherapy. This resulted in a decline of the "immunoregulatory balance" (helper/suppressor ratio). Although this ratio had been higher in both groups of patients than in healthy age- and sex-matched controls before therapy, it became normal and subnormal during and after radiotherapy. The clinical significance of the differential influence of radiotherapy on T-lymphocyte subpopulations remains to be determined.     

The effect of lucanthone on sublethal radiation damage, in vivo

The capacity of the Chinese hamster jejunal crypt cell to accumulate and repair sublethal radiation damage was determined by analyzing the return of the shoulder of the radiation dose-crypt microcolony survival curve (Dr) after a priming dose of 1250 rad. The control split dose crypt cell survival curve exhibited a D0, Dr and "n" of 179 +/- 3 rad, 261 +/- 3 rad and 4.3 respectively; repair of sublethal radiation damage was completed by two hours post-irradiation. The effect of lucanthone (an antischistosomal DNA intercalating agent) on the crypt cell's capacity to accumulate and repair sublethal radiation damage was determined by injecting the drug (100 mg/kg, i.p.) at intervals before irradiation with a priming dose of 1250 rad, followed two hours later by graded doses. Injection coincident with the priming dose of radiation resulted in a 22 rad reduction of the Dr (compared to control Dr). Injection eight hours before the priming dose almost completely inhibited the accumulation and repair of sublethal radiation damage so that the resultant Dr two hours later was only 29 rad (a 232 rad reduction). At no time was the D0 of the crypt cell survival curve affected by lucanthone. These data confirm previous results from whole crypt analysis and LD50/7 analysis that non-toxic concentrations of lucanthone reversibly inhibit the accumulation and repair of sublethal radiation damage in a time-dependent manner with complete inhibition approximately eight hours post-injection. This drug is useful for the study of sublethal radiation damage in vivo and may be beneficial in radiation therapy of cancer when it is desirable to inhibit the repair of sublethal radiation damage.     

非小细胞肺癌术后放疗的临床意义

目的　观察非小细胞肺癌 (NSCLC)术后放疗的价值。材料与方法　回顾性分析我院自 1985 - 0 1～1995 - 12经手术治疗的非小细胞肺癌 170例 ,分为单纯手术组 (单术组 ) 94例 ,手术加放疗组 (术放组 ) 76例 ,单术组Ⅰ、Ⅱ期病例略多。单术组术后未再接受其他治疗 ;术放组术后 2～ 4周进行放疗 ,6MV -X线常规分割外放疗DT5 0GY～ 60GY。分别统计 2组间 5年总生存率、5年无瘤生存率、局部复发率和远处转移率 ,为了排除 2组间病期早晚对顾后的影响 ,还单独分析了Ⅲ期病例 2组间各分析指标的差别 ,统计采用X2 检验。结果　单术组和术放组的 5年总生存率分别为 31 9% (30 / 94 ) ,31 6% (2 4 / 76) ,(P >0 0 5 )。 5年无瘤生存率分别为 2 5 5 % (2 4 / 94 ) ,2 8 9% (2 6/ 76) ,(P >0 0 5 )。 2组局部复发率分别为 31 9% (30 / 94 ) ,2 3 7% (18/ 76) ,(P>0 0 5 )。远转率分别为 4 8 9% (4 6/ 94 ) ,4 4 7% (34 / 76) (P >0 0 5 )。单纯分析Ⅲ期病例 ,单术组和术放组 5年无瘤生存率分别为 2 5 % (14 / 5 6) ,38 7% (2 4 / 62 ) (P >0 0 5 )。 2组局部复发率分别为 39 3% (2 2 / 5 6) ,2 4 2 % (15 / 62 ) ,(0 0 5

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2017—2019年广西省部分医用电子直线加速器质量控制检测结果分析

目的 了解广西省医用电子直线加速器设备性能的质量控制水平,为卫生行政部门研究制定医用电子直线加速器卫生标准和质量控制检测规范提供技术支持。方法 采用随机抽样方法,对广西省部分医用电子直线加速器进行质控检测。结果 2017—2019年累计检测118台次加速器,加速器质控检测（包括X射线和电子束）总初检合格率为56.8%,总复检合格率为96.6%;二级、三级医院加速器质控检测初检合格率分别为32.0%、62.2%,差异有统计学意义（P < 0.05）,初检合格率最低的指标是辐射剂量示值误差,其次是辐射野均整度。结论 广西省医用电子直线加速器质量控制水平有待提高;卫生行政部门应进一步加强对加速器质控检测的监督,定期开展加速器质控检测。     

504名放射工作人员淋巴细胞微核率分析

目的 了解长期接触低剂量电离辐射的放射工作人员外周血淋巴细胞微核率的总体水平,为采取相应的放射防护措施提供依据。方法 以2019年1—12月504名资料完整的在岗放射工作人员为放射组,以岗前职业健康检查拟从事放射工作的105名健康成年人为对照组,2组均采用常规培养法测定周围血淋巴细胞微核率,分析比较检测结果。结果 放射组微核率高于对照组（P < 0.001）;女性放射工作人员微核率高于男性（P < 0.01）;不同年龄组微核率差异有统计学意义（P < 0.05）,其中年龄41～50岁的微核率高于21～30岁（P < 0.05）;不同工龄组微核率差异有统计学意义（P < 0.05）,其中21～30年的微核率高于0～10年（P < 0.05）;不同工种间的微核率差异有统计学意义（P < 0.01）,放射治疗岗位人员的微核率较其他岗位最高;不同级别的单位放射工作人员微核率中,市级医院最高,其中省级医院与企业（P < 0.05）、市级医院之间（P < 0.01）的微核率的差异有统计学意义。结论 放射工作人员的微核率高于非接触人员,女性的微核率高于男性,放射治疗的工作人员的微核率较高,应加强对此类人群的放射防护与日常管理。     

香烟辐射水平及所致吸烟者剂量

目的 评估我国吸烟人群因吸烟所致内照射剂量并与其他国家进行比较。方法 收集并分析国内外香烟中²¹⁰Po/²¹⁰Pb辐射水平,推荐主流烟雾中²¹⁰Po/²¹⁰Pb份额,进行我国吸烟者因吸烟所致内照射剂量估算。结果 2015年中国15岁及以上成人现在吸烟者为3.2亿,日平均吸烟量为15.2支;按文献中香烟品牌数量加权的²¹⁰Po /²¹⁰Pb活度均值分别为28.2 mBq/支和39.3 mBq/支;在剂量估算中,²¹⁰Po主流烟雾份额采用模拟装置和志愿者实验结果均值20%,²¹⁰Pb主流烟雾份额采用模拟装置实验结果10%。根据我国日平均吸烟量和现在吸烟者人数估算的我国现在吸烟者年有效剂量为126 μSv·a^-1,集体有效剂量为40746人·Sv。结论 我国香烟中²¹⁰Po/²¹⁰Pb含量约为其它国家香烟的2～3倍,但由于本文采用的主流烟雾份额和²¹⁰Po/²¹⁰Pb剂量转换系数不同于其它文献,所以本文估算的我国吸烟人员吸20支烟所受剂量低于部分国家。