Today, dosimeters are used generally for dosimetry of the diagnostic X-ray beam. Ionization chambers are appropriate instruments for monitoring and also the dosimetry of X-ray beam in medical diagnostic equipment. The...Today, dosimeters are used generally for dosimetry of the diagnostic X-ray beam. Ionization chambers are appropriate instruments for monitoring and also the dosimetry of X-ray beam in medical diagnostic equipment. The present work introduces design and investigation of a new ring-shaped monitor chamber with a PMMA body, graphite-coated PMMA windows (0.5 mm thick), a special graphite-foil central electrode (0.1 mm thick, 0.7 g/cm3 dense) that creating two sensitive volumes and a central hole for crossing the radiation beam with less attenuation. The results of performance tests conducted at the Nuclear Science and Technology Research Institute, AEOI in Karaj- Iran proved the high short and long-term stability, the very low leakage current, the low directional dependence and very high ion collection efficiency through the special design of the collecting electrode. Moreover, the FLUKA Monte Carlo simulations certified the negligible effect of central electrode on this new ring-shaped monitor chamber. According to the results of the performance tests, the new monitor chamber can be used as a standard dosimeter in order to monitor X-ray beam in primary standard dosimetry laboratories.展开更多
目的：对经尿道针状电极行膀胱部分切除术治疗膀胱肿瘤的初步经验进行总结。方法：应用等离子针状电极对8例膀胱肿瘤患者进行经尿道膀胱部分切除术,观察术中及术后并发症,术后病理分期,总结手术操作经验。结果：所有患者在硬膜外麻醉下...目的：对经尿道针状电极行膀胱部分切除术治疗膀胱肿瘤的初步经验进行总结。方法：应用等离子针状电极对8例膀胱肿瘤患者进行经尿道膀胱部分切除术,观察术中及术后并发症,术后病理分期,总结手术操作经验。结果：所有患者在硬膜外麻醉下均可耐受手术,术中出血量极少或几乎无出血,无尿外渗,闭孔神经反射可控。术后无继发出血及尿路刺激症状。获得完整肿瘤病理分期：T1期5枚,T2a期5枚,T2 b 期2枚。随访2~3个月,患者无不适。结论：等离子针状电极能安全有效地应用于经尿道膀胱部分切除术。展开更多
文摘Today, dosimeters are used generally for dosimetry of the diagnostic X-ray beam. Ionization chambers are appropriate instruments for monitoring and also the dosimetry of X-ray beam in medical diagnostic equipment. The present work introduces design and investigation of a new ring-shaped monitor chamber with a PMMA body, graphite-coated PMMA windows (0.5 mm thick), a special graphite-foil central electrode (0.1 mm thick, 0.7 g/cm3 dense) that creating two sensitive volumes and a central hole for crossing the radiation beam with less attenuation. The results of performance tests conducted at the Nuclear Science and Technology Research Institute, AEOI in Karaj- Iran proved the high short and long-term stability, the very low leakage current, the low directional dependence and very high ion collection efficiency through the special design of the collecting electrode. Moreover, the FLUKA Monte Carlo simulations certified the negligible effect of central electrode on this new ring-shaped monitor chamber. According to the results of the performance tests, the new monitor chamber can be used as a standard dosimeter in order to monitor X-ray beam in primary standard dosimetry laboratories.
文摘目的：对经尿道针状电极行膀胱部分切除术治疗膀胱肿瘤的初步经验进行总结。方法：应用等离子针状电极对8例膀胱肿瘤患者进行经尿道膀胱部分切除术,观察术中及术后并发症,术后病理分期,总结手术操作经验。结果：所有患者在硬膜外麻醉下均可耐受手术,术中出血量极少或几乎无出血,无尿外渗,闭孔神经反射可控。术后无继发出血及尿路刺激症状。获得完整肿瘤病理分期：T1期5枚,T2a期5枚,T2 b 期2枚。随访2~3个月,患者无不适。结论：等离子针状电极能安全有效地应用于经尿道膀胱部分切除术。
