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171.
This study sought to demonstrate the feasibility of estimating the source strength during implantation in brachytherapy. The requirement for measuring the strengths of the linked sources was investigated. The utilized sources were 125I with air kerma strengths of 8.38–8.63 U (μGy m2 h–1). Measurements were performed with a plastic scintillator (80 mm × 50 mm × 20 mm in thickness). For a source-to-source distance of 10.5 mm and at source speeds of up to 200 mm s–1, a counting time of 10 ms and a detector-to-needle distance of 5 mm were found to be the appropriate measurement conditions. The combined standard uncertainty (CSU) with the coverage factor of 1 (k = 1) was ∼15% when using a grid to decrease the interference by the neighboring sources. Without the grid, the CSU (k = 1) was ∼5%, and an 8% overestimation due to the neighboring sources was found to potentially cause additional uncertainty. In order to improve the accuracy in estimating source strength, it is recommended that the measurment conditions should be optimized by considering the tradeoff between the overestimation due to the neighboring sources and the intensity of the measured value, which influences the random error.  相似文献   
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Immature seeds of five bean cultivars (flageolet-type and those intended for dry-seed production) were assessed for changes in water-soluble carbohydrates including raffinose family oligosaccharides (RFOs) due to boiling, sterilization, and storage of the sterilized product. About 100?g fresh weight of edible portion of fresh bean seeds contained 2449.3–3182.6?mg total soluble sugars, of which RFOs comprised 44–49%. The highest amounts of these compounds were found in the seeds of the cultivars Laponia and Mona. The dominant oligosaccharide was stachyose. Boiling fresh seeds to consumption consistency reduced total soluble sugars and RFOs: average values were 57% and 55%, respectively. Sterilization in cans resulted in 65% reductions of both total soluble sugars and RFOs. In general, there were no changes in the content of soluble sugars in canned and sterilized products stored for 12?months.  相似文献   
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目的探讨彩超检测血流阻力指数(RI)联合血清CA-125对子宫内膜癌的诊断价值及影响因素。方法收集2012年1月-2013年12月,我院收治的子宫内膜癌患者65例,进行彩超声检查并检测其血清CA-125水平,分析RI值、CA-125与组织学分级、临床分级、子宫肌层浸润深度、盆腔淋巴结转移之间的关系。结果 RI随病理分级、临床分期升高、肌层浸润深度的增加及盆腔淋巴结转移而降低;CA-125随肌病理分级、临床分期升高及盆腔淋巴结转移而升高(P〈0.05)。结论子宫内膜癌患者的彩超RI值与CA-125水平与病理特征密切相关,术前进行彩超检查肿瘤血流RI以及血清CA-125水平对于子宫内膜癌的诊断及治疗方案选择具有重要指导意义。  相似文献   
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《Clinical therapeutics》2020,42(8):1612-1616
PurposeThe purpose of this case report was to investigate the clinical efficacy and tolerability of anti–programmed cell death protein (PD)-1 antibody combined with iodine (I)-125 seed brachytherapy in lung cancer treatment.MethodsThree patients with advanced PD-L1–positive non–small-cell lung cancer were treated first with I-125 seed brachytherapy and then with anti–PD-1 antibody. Clinical efficacy was evaluated with Response Evaluation Criteria in Solid Tumors.FindingsAll 3 patients had complete response or partial response. None of the 3 patients had reported obvious adverse events.ImplicationsEncouraging preliminary results provide important support for further clinical treatment of lung cancer using anti–PD-1 antibody combined with I-125 seed brachytherapy.  相似文献   
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目的研究重组融合蛋白dTMP-GH在小鼠体内的分布情况,明确其是否具有靶向分布特点。方法实验室制备dTMP-GH重组融合蛋白;用放射性125I标记融合蛋白dTMP-GH后,按100μg/kg的标准小鼠尾静脉注射125I-dTMP-GH,分别于给药后5 min、15 min、30 min、1 h、2 h、4 h、8 h、12 h、24 h取心、肝、脾、肾、股骨、甲状腺等进行放射性计数。结果制备得到纯度大于98%的重组融合蛋白dTMP-GH;125I标记率为71.53%,放化纯度为96.53%,比活度为0.22 MBq/μl;尾静脉注射125I标记的dTMPGH后30 min股骨的放射性计数占到注射总量的10%,并随时间推移经肝脏和肾脏代谢。结论融合蛋白dTMP-GH经尾静脉注射后在小鼠体内主要分布于骨髓,具有骨髓组织偏向分布特点。  相似文献   
177.
目的探讨彩色多普勒超声(CDFI)引导下125I粒子组织间植入治疗转移性浅表肿瘤的疗效。方法回顾性分析156例确诊为恶性转移性浅表肿瘤患者进行125I粒子治疗结果,利用薄层CT扫描图像进行计算机三维治疗计划系统(TPS)术前计划、术中调整、术后验证粒子分布及数量。局部浸润麻醉后,CDFI引导下植入125I粒子。结果术后3个月,16.7%(26/156)患者肿瘤完全缓解,51.3%(80/156)患者肿瘤部分缓解,21.1%(33/156)肿瘤稳定,10.9%(17/156)肿瘤进展,总有效率(CR+PR)为68%。术后6个月,18.6%(29/156)患者肿瘤完全缓解,53.2%(83/156)患者肿瘤部分缓解,22.4%(35/156)肿瘤稳定,5.8%(9/156)肿瘤进展,总有效率(CR+PR)为71.8%。无严重皮肤反应、骨髓抑制及其它并发症发生。结论 CDFI引导下125I粒子植入治疗转移性浅表肿瘤具有方法简单、定位准确、疗效确切、无严重并发症等优点,是一种安全的微创治疗手段。  相似文献   
178.
??Abstract??Objective To explore the role of miR-125b in pediatric classical APL?? in order to seek new therapeutic strategies for drug resistant APL. Methods The target genes of miR-125b were predicted online?? validated by Dual-luciferase assay and western blot assay. MiR-125b expression levels were measured in 33 matched-pair APL samples??treated in the First Affiliated Hospital of Sun Yat-sen University and other members of South China Children APL Cooperative Group from March 2007 to September2012??at initial diagnosis and complete remission ??CR?? and in 5 relapsed patients by qRT-PCR. Proliferation and apoptosis were analyzed respectively using the RNA transfection?? MTT assay and flow cytometry. Results The expression of miR-125b was up-regulated in pediatric APL at diagnosis and relapse bone marrow samples?? but returned to normal after complete remission?? miR-125b could promote leukemic cell proliferation and inhibit cell apoptosis by regulating the expression of tumor suppressor Bak1. Remarkably??it was also found to be up-regulated in leukemic drug-resistant cells??NB4-R1??NB4-R2??HL-60/DOX???? and overexpression of exogenous miR-125b could increase their resistance to therapeutic drugs. Conclusion MiR-125b can regulate pediatric classical APL cells proliferation?? apoptosis and drug resistance by repressing BAK1 protein expression.  相似文献   
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