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MDCT肺动脉血管成像:以标准化的速率注入等量碘剂时血管内对比增强与碘浓度无关 被引量:4
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作者 S.Keil C.Plumhans +4 位作者 F.F.Behrendt m.das S.Stanzel G.Mühlenbruch 赵艳萍 《国际医学放射学杂志》 2008年第5期421-421,共1页
对192例已知或可疑肺栓塞病人行16层CT肺血管成像(MDCTA),使用2种不同浓度的对比剂,以标准化碘注射率(iodine delivery rate,IDR)与总碘负荷注射,比较对血管内碘浓度的影响。A组103例接受148mL浓度为300mgI/mL的对比剂(优维显3... 对192例已知或可疑肺栓塞病人行16层CT肺血管成像(MDCTA),使用2种不同浓度的对比剂,以标准化碘注射率(iodine delivery rate,IDR)与总碘负荷注射,比较对血管内碘浓度的影响。A组103例接受148mL浓度为300mgI/mL的对比剂(优维显300^TM,拜耳先灵公司),注射速率4.9mL/s;B组89例接受120mL浓度为370mgI/ZmL碘剂(优维显370TM),注射速率4.0mL/s,以形成IDR(1.5gI/s)和相同的碘剂总量(44.4g)。2种对比剂注射后均给予生理盐水。分别在肺动脉主干、升主动脉和降主动脉处测量平均密度值。肺动脉主干的平均CT值A组为(355±116)HU, 展开更多
关键词 多层螺旋CT肺血管成像 肺栓塞 对比剂浓度
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Response of C_(2)H_(2)F_(4)superheated emulsion to quasi-mono-energetic neutrons at low frequency
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作者 V.Kumar m.das +5 位作者 S.Ali N.Biswas R.Shil K.Banerjee P.Pallav M.Nandy 《Radiation Detection Technology and Methods》 CSCD 2024年第2期1202-1207,共6页
Background The response of superheated emulsion detector with different halocarbons as active liquid to poly-energetic and mono-energetic neutrons has been carried out by different workers.The C_(2)H_(2)F_(4)detectors... Background The response of superheated emulsion detector with different halocarbons as active liquid to poly-energetic and mono-energetic neutrons has been carried out by different workers.The C_(2)H_(2)F_(4)detectors have not been explored much.This liquid has shown the potentiality of sensitivity to low-mass dark matter.The previous calibration of this liquid was carried out with the poly-energetic neutrons.Purpose In the present work,to better characterize the detector with neutrons,it is irradiated with quasi-mono-energetic neutrons and the results are compared with neutrons from 241Am-Be.To run the detector for the dark matter search,it is required to calibrate it with neutrons,preferably with mono-energetic neutrons.But mono-energetic neutron is not available at all establishments;hence,it was calibrated with quasi-mono-energetic neutrons.Method The response of superheated emulsion consisting of the droplets of C_(2)H_(2)F_(4)has been studied using the quasi-mono-energetic neutrons.The superheated droplets have been fabricated in a visco-elastic gel matrix.The shock waves generated by the passage of the energetic particles are detected by the acoustic sensors coupled to the emulsion.The measurement has also been carried out for the blank target and beam-off conditions.Results and conclusion It is observed that the(Pvar)response of the emulsion in the low-frequency range is sharper for the quasi-mono-energetic neutrons from 7Li(p,n)reaction and wider for the poly-energetic neutrons from 241Am-Be.The fundamental frequency associated with bubble nucleation(FF values)is similar for the neutrons from 7Li-target and 241Am-Be source.The precise characterization of such detector is required for the application in neutron measurement as well as for the dark matter search experiment apart from the basic understanding of the radiation-induced bubble nucleation. 展开更多
关键词 Superheated emulsion Bubble nucleation-Low frequency Quasi-mono-energetic Neutrons
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