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51.
常规染色体畸变分析法对AT细胞高辐射敏感性的研究   总被引:2,自引:0,他引:2  
目的 研究毛细血管扩张性共济失调症(ataxia-telangiectasia,AT)患者皮肤的成纤维细胞系AT5BIVA(AT细胞)的高辐射敏感性。方法 以源于正常人皮肤的成纤维细胞系GM0639(GM细胞)为对照,用常规染色体畸变分析法,在AT细胞和GM细咆经60COγ射线0、1、2、3、4 Gy照射后,观察比较AT细胞和GM细胞之间染色体畸变率(CAF)的差异,并分别进行曲线拟合。结果 在0、1、2、3、4 Gy剂量下,AT细胞染色体畸变率明显高于GM细胞(P<0.05);AT和GM细胞染色体畸变率与剂量成正相关,均可拟合成剂量效应直线方程Y=a+bX,且AT细胞剂量效应直线回归方程斜率明显大于GM细胞(P<0.05)。结论 AT患者AT细胞的辐射敏感性显著高于GM细胞,具有高辐射敏感性。  相似文献   
52.
本文报道,75mGy/(12.5mGy/min)单次全身X射线照射后9小时用SRBC免疫C57BL/6小鼠,在免疫后4天和7天脾脏、胸腺和下丘脑cAMP含量均降低;而在免疫后4天脾脏去甲肾上腺素、肾上腺素和酪氨酸含量均增高,免疫后7天肾上腺素含量仍持续增高;当连接γ射线65mGy(0.015mGy/min,6h/d)全身照射小鼠后即刻或29小时后免疫,脾脏和下丘脑cAMP含量也均降低。提示,低剂量  相似文献   
53.
Background Cosmetic changes are to be expected after radiotherapy for skin tumours. Objectives This study aimed to answer the questions: How frequent are cosmetic changes after soft X‐ray therapy? Do treatment parameters, tumour thickness, localization and size of the irradiated field have a major influence? Were patients irritated by the visual appearance of the irradiated field? Methods In total, 2474 examinations of 1149 irradiated fields were performed. Results Hypopigmentation was found in 64.7% of examinations more than 90 days after therapy, teleangiectases in 43.1%, erythema in 24.8%, and hyperpigmentation in 16.8%. The frequency of hypopigmentation, teleangiectases and hyperpigmentation increased with time from X‐ray exposure; more than 4 years after therapy hypopigmentation was diagnosed in 91.8% and teleangiectases in 82.2% of examinations. Total dose, the time–dose–fractionation factor (TDF), field size and dose per fraction were significantly related to the frequency of cosmetic changes. Incidence rates of cosmetic changes differed by less than 15% if different treatment conditions were compared: thicker vs. thinner tumours, larger vs. smaller fields, higher vs. lower total doses, doses per fraction, and TDF. Frequencies of hypopigmentation, teleangiectases, erythema and hyperpigmentation differed by more than 15% between some localizations on the head. Women reported irritation by the visual appearance of the irradiated field in 12.6% of 1116 interviews, and men in 4.4% of 1284 interviews. Conclusions Cosmetic changes after soft X‐ray therapy are relatively frequent. Treatment parameters, tumour thickness and field size have only a minor influence. Few patients, but more women than men, were irritated by the visual appearance of the irradiated field.  相似文献   
54.
目的探索调强放射治疗 (IMRT)提高进展期胰腺癌局部肿瘤靶区剂量以及减少周围正常组织照射剂量的可能性。 方法 2 1例局部进展期胰腺癌患者接受同期放化疗。放射治疗分第一阶段予常规放射治疗 ,剂量30Gy/ 15次 / 3周 ;第二阶段强调放射治疗 ,肿瘤靶区分割剂量 3Gy/次 ,总剂量为 2 1~30Gy ,在 2周内分 7~10次完成。总剂量递增水平 :5 1、5 4、5 7、6 0Gy。在放射治疗过程中 ,每个治疗日 5 -FU静脉点滴。 结果 16例完成治疗计划 ,分别为 5 1Gy 3例、5 4Gy 3例、5 7Gy 3例 ,6 0Gy 7例。 13例治疗前CA19- 9值升高 ,中位值治疗前后分别为 716、2 5 5U/ml(P <0 .0 0 1)。 14例以疼痛为主的患者至少减少 1/ 3~1/ 2的麻醉药品用量 ,其中 5例疼痛症状完全消失。10例患者治疗后卡氏评分有提高。 结论局部进展期胰腺癌患者接受适形调强放疗并同期应用 5 -Fu化疗增敏 ,可获得确切的姑息治疗作用 ,肿瘤剂量 6 0Gy分 2 5次在 5周完成 ,无严重的放射治疗相关的急性毒性反应  相似文献   
55.
The management of clival chordoma remains problematic. We present the case of a 48-year-old woman with clival chordoma who underwent multiple surgeries and radiation therapy, including gamma knife stereotactic radiosurgery (GK-SRS), during a 10-year clinical course. The tumor was initially removed by gross total resection via the trans-sphenoidal approach, followed by external linac radiation therapy. The tumor recurred at the clivus 5 years after the initial operation. After repeated trans-sphenoidal removal of recurrent tumors, she twice underwent GK-SRS for a tumor remnant adjacent to the brainstem. Although this part of the tumor was controlled by GK-SRS, there was further tumor extension toward the sphenoid and maxillary sinuses. Ultimately, lower cranial nerve dysfunction developed due to tumor extension into the lower part of the clivus and the patient died of respiratory failure. Autopsy revealed the tumor to extend from the lower clivus to the bilateral middle fossae. The lower part of the tumor extended to the nasal cavity and to the posterior wall of the pharynx, resulting in compression of the upper pharyngeal region. The tumor around the jugular foramen compressed the lower cranial nerves bilaterally. Tumor cells did not, however, invade the intradural space microscopically. Although chordoma is not biologically malignant, this tumor can show massive extension with destruction of bony structures and extracranial invasion of connective tissues. Therefore, the optimal treatment strategy is to remove the tumor mass as extensively as possible, including normal bony structures and connective tissues surrounding the tumor, using skull base surgical techniques.  相似文献   
56.
The effect of single and repeated UVB radiation on rabbit cornea   总被引:1,自引:0,他引:1  
Background Cumulative effect of ultraviolet radiation (UVR) is an important aspect of UV corneal damage. The purpose of this study was to apply high resolution magic angle spinning proton nuclear magnetic resonance (HR-MAS 1H NMR) spectroscopy to evaluate the effect of single and repeated UV radiation exposure of the same overall dose on the rabbit cornea.Methods Corneal surfaces of 24 normal rabbit eyes were examined for the effects of UVB exposure (312 nm). In the first group (UVB1), animals were irradiated with a single dose (3.12 J/cm2; 21 min) of UVB radiation. The animals in the second group (UVB2) were irradiated three times for 7 min every other day (dose of 1.04 J/cm2; days 1, 3, 5) to give the same overall dose (3.12 J/cm2). The third group served as an untreated control group. One day after the last irradiation, the animals were sacrificed, and the corneas were removed and frozen. HR-MAS 1H NMR spectra from intact corneas were obtained. Special grouping patterns among the tissue samples and the relative percentage changes in particular metabolite concentrations were evaluated using modern statistical methods (multivariate analysis, one-way ANOVA).Results The metabolic profile of both groups of UVB-irradiated samples was significantly different from the control corneas. Substantial decreases in taurine, hypo-taurine and choline-derivatives concentrations and substantial elevation in glucose and betaine levels were observed following the UVR exposure. There was no significant difference between the effect of a single and repeated UVB irradiation of the same overall dose.Conclusions For the first time, the effects of single and repeated UVR doses on the metabolic profile of the rabbit cornea were analysed and compared. The combination of HR-MAS 1H NMR spectroscopy and modern statistical methods (multivariate analysis, one-way ANOVA) proved suitable to assess the overall view of the metabolic alterations in the rabbit corneal tissue following UVB radiation exposure.  相似文献   
57.
目的 :观察 Fas、Bcl- 2在 γ射线体外诱发的急性淋巴细胞白血病小鼠骨髓细胞中表达情况 ,以探讨辐射致癌的机制。方法 :采用 4次 1.75 Gyγ射线全身照射 BAL B/ c小鼠诱发白血病模型 ,通过流式细胞仪对照射后白血病组、未癌变组及对照组小鼠骨髓细胞中 Fas、Bcl- 2的表达进行检测 ;应用抗 Fas抗体诱导细胞凋亡 ,进一步观察 Fas、Bcl- 2的表达对骨髓细胞凋亡的影响。 结果 :白血病小鼠骨髓细胞 Fas表达较未癌变组及对照组明显下降 (P<0 .0 1) ,而 Bcl- 2的表达明显增强 (P<0 .0 1) ;白血病小鼠骨髓细胞明显耐受抗 Fas抗体诱导的细胞凋亡。 结论 :Fas低表达、Bcl- 2高表达导致了细胞凋亡受到抑制 ,这可能是辐射引起小鼠急性淋巴细胞白血病的机制之一。  相似文献   
58.
目的:研究不同剂量的放射性125I粒子对家兔尿道的放射性损伤。方法:麻醉下将放射性125I粒子植入雄性家兔尿道旁1.0cm处。125I粒子的放射性粒子活度分别为14.8MBq(A组)、29.6MBq(B组)和44.4MBq(C组),对照组(D组)仅尿道旁种植相当于粒子大小无放射性的无菌铅管1粒。植入后4周,摄尿道片,观察粒子位置等情况;原手术切口切开,取放射粒子周围2.0cm范围内的家兔尿道组织作肉眼、光学显微镜和电子显微镜观察,进行放射性损伤的评价。结果:术后4周,肉眼及光学显微镜观察,实验组与对照组粒子周围的尿道粘膜、粘膜下及肌层所见基本一致;C组少部分电镜视野中观察到尿道上皮胞质出现较多空泡变性、空化、嵴稀疏等超微结构的损伤。光镜下尿道入射性损伤评分,A、B、C、D组分别为(2.20±0.18)、(2.23±0.15)、(2.27±0.10)、(2.10±0.17)分,A、B、C组与D组相比,差异无显著性(P>0.05)。对线粒体作FlaMeng半定量分析,A、B、C、D各组评分分别为(1.23±0.13)、(1.34±0.25)、(1.41±0.30)、(1.12±0.13)分,A、B、C各组与D组(对照组)相比,差异无显著性(P>0.05)。结论:放射性125I粒子对尿道放射性损伤随粒子的放射性活度的增加而逐渐加重,呈明显的放射性活度效应关系;正常剂量的放射性粒子对尿道的损伤是很轻微的,是安全可行的。  相似文献   
59.
^125I放射微粒微创植入治疗前列腺癌   总被引:1,自引:0,他引:1  
目的观察^125I放射微粒植入对前列腺癌的治疗效果。方法对26例临床确诊为前列腺癌患者经皮穿刺在癌组织植入^125I放射微粒,每例平均36粒,术后复查肛诊、B超、影像学及血生化指标。结果患者植入治疗经过顺利,2例少量出血,留置导尿后愈合,3个月后经肛诊、直肠B超示结节缩小,前列腺特异性抗原(PSA)降低,多普勒超声显示结节内动脉收缩期最大血流速度(VS)、阻力指数(RI)及动脉搏动指数(PI)均明显下降。结论^125I放射微粒植入对前列腺癌的治疗安全性好、效果可靠。  相似文献   
60.
肿瘤物理治疗技术及设备   总被引:1,自引:0,他引:1  
简要介绍了肿瘤的放射治疗和热治疗的技术及设备,介绍了各种技术及设备的特点。  相似文献   
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