目的研究无痛胃肠镜检查前预防性静脉注射甲氧明对检查过程中血流动力学的影响。方法在此项前瞻性研究中,2019年12月1日至12月31日在首都医科大学附属北京友谊医院纳入拟接受无痛胃肠镜检查的患者64例,按照SPSS生成的随机数,随机分为甲...目的研究无痛胃肠镜检查前预防性静脉注射甲氧明对检查过程中血流动力学的影响。方法在此项前瞻性研究中,2019年12月1日至12月31日在首都医科大学附属北京友谊医院纳入拟接受无痛胃肠镜检查的患者64例,按照SPSS生成的随机数,随机分为甲氧明组和对照组,每组各32例。甲氧明组患者在麻醉诱导给药后立即注射盐酸甲氧明1~2 mg,对照组患者注射等量生理盐水。比较两组患者检查前、诱导给药后即刻、检查开始3 min、5 min、10min、15 min以及检查结束时的血压、心率、脉搏血氧饱和度、检查时间、苏醒时间、麻醉及血管活性药等用量和不良事件。结果与对照组相比,甲氧明组患者在诱导给药后即刻(95±11 mm Hg vs.84±11 mm Hg,P<0.001)以及检查开始3 min(84±14 mm Hg vs.78±9 mm Hg,P=0.026)、5 min(83±12 mm Hg vs.75±9 mm Hg,P=0.019)时的平均动脉压更高,差异具有统计学意义;但甲氧明组患者的心动过缓(心率<50次/分)的发生率更高(18.8%vs.0,P=0.032),差异具有统计学意义。两组的脉搏血氧饱和度、检查时间、苏醒时间、麻醉药物、血管活性药物用量等比较,差异无统计学意义(P>0.05)。结论无痛胃肠镜检查前预注甲氧明有助于维持诱导期血流动力学稳定,但需密切监测心动过缓或必要时静注阿托品处理。展开更多
Lower hybrid current drive experiments on the HT-7 device have been carried out by scanning the following parameters: central line averaged electron density (ne = 0.6 - 2.0 × 1019m-3) and toroidal magnetic field ...Lower hybrid current drive experiments on the HT-7 device have been carried out by scanning the following parameters: central line averaged electron density (ne = 0.6 - 2.0 × 1019m-3) and toroidal magnetic field (Bt = 1.62 - 2.0 T). The dependence of current drive efficiency on these parameters has been studied and the experimental curves of current drive efficiency as a function of ne and Bt have also been obtained. From these experimental results, it can be seen that current drive efficiency rises with the increase of toroidal magnetic field. As plasma density increases, the current drive efficiency first increases to a certain value, then gradually decreases, that is, there exists an optimized density regime where a better drive efficiency can be obtained. The analysis shows that the current drive efficiency is mainly affected by wave accessibility and impurity concentration, and the competition of these two factors determines the current drive efficiency.展开更多
Lower hybrid current drive(LHCD)experiments have been done on the superconducting Tokamak HT-7 by using a new developed long pulse megawatt lower hybrid wave system.An LHCD efficiency of 0.5×10^(19)A·m^(-2)/...Lower hybrid current drive(LHCD)experiments have been done on the superconducting Tokamak HT-7 by using a new developed long pulse megawatt lower hybrid wave system.An LHCD efficiency of 0.5×10^(19)A·m^(-2)/W in a pulse length of several hundreds of milliseconds has been achieved.After boronization of the tokamak vacuum vessel,considerable improvements of plasma energy confinement and particle confinement during LHCD phase have been achieved by adjusting wave spectra.An energy transfer from the lower hybrid wave to plasma bulk electrons has been demonstrated experimentally.A computer simulation of the LHCD experiments by using a ray tracing code combined with a two dimensional Fokker-Planck code is in good accordance with experimental measurements and suggests an important role of plasma current profile.展开更多
文摘目的研究无痛胃肠镜检查前预防性静脉注射甲氧明对检查过程中血流动力学的影响。方法在此项前瞻性研究中,2019年12月1日至12月31日在首都医科大学附属北京友谊医院纳入拟接受无痛胃肠镜检查的患者64例,按照SPSS生成的随机数,随机分为甲氧明组和对照组,每组各32例。甲氧明组患者在麻醉诱导给药后立即注射盐酸甲氧明1~2 mg,对照组患者注射等量生理盐水。比较两组患者检查前、诱导给药后即刻、检查开始3 min、5 min、10min、15 min以及检查结束时的血压、心率、脉搏血氧饱和度、检查时间、苏醒时间、麻醉及血管活性药等用量和不良事件。结果与对照组相比,甲氧明组患者在诱导给药后即刻(95±11 mm Hg vs.84±11 mm Hg,P<0.001)以及检查开始3 min(84±14 mm Hg vs.78±9 mm Hg,P=0.026)、5 min(83±12 mm Hg vs.75±9 mm Hg,P=0.019)时的平均动脉压更高,差异具有统计学意义;但甲氧明组患者的心动过缓(心率<50次/分)的发生率更高(18.8%vs.0,P=0.032),差异具有统计学意义。两组的脉搏血氧饱和度、检查时间、苏醒时间、麻醉药物、血管活性药物用量等比较,差异无统计学意义(P>0.05)。结论无痛胃肠镜检查前预注甲氧明有助于维持诱导期血流动力学稳定,但需密切监测心动过缓或必要时静注阿托品处理。
文摘Lower hybrid current drive experiments on the HT-7 device have been carried out by scanning the following parameters: central line averaged electron density (ne = 0.6 - 2.0 × 1019m-3) and toroidal magnetic field (Bt = 1.62 - 2.0 T). The dependence of current drive efficiency on these parameters has been studied and the experimental curves of current drive efficiency as a function of ne and Bt have also been obtained. From these experimental results, it can be seen that current drive efficiency rises with the increase of toroidal magnetic field. As plasma density increases, the current drive efficiency first increases to a certain value, then gradually decreases, that is, there exists an optimized density regime where a better drive efficiency can be obtained. The analysis shows that the current drive efficiency is mainly affected by wave accessibility and impurity concentration, and the competition of these two factors determines the current drive efficiency.
文摘Lower hybrid current drive(LHCD)experiments have been done on the superconducting Tokamak HT-7 by using a new developed long pulse megawatt lower hybrid wave system.An LHCD efficiency of 0.5×10^(19)A·m^(-2)/W in a pulse length of several hundreds of milliseconds has been achieved.After boronization of the tokamak vacuum vessel,considerable improvements of plasma energy confinement and particle confinement during LHCD phase have been achieved by adjusting wave spectra.An energy transfer from the lower hybrid wave to plasma bulk electrons has been demonstrated experimentally.A computer simulation of the LHCD experiments by using a ray tracing code combined with a two dimensional Fokker-Planck code is in good accordance with experimental measurements and suggests an important role of plasma current profile.
