Background Intrathecal anesthesia is commonly used for cesarean section. Bupivacaine and ropivacaine have all been used as intrathecal drugs. The minimum effective local anesthetic dose （MLAD） of intrathecal ropivac...Background Intrathecal anesthesia is commonly used for cesarean section. Bupivacaine and ropivacaine have all been used as intrathecal drugs. The minimum effective local anesthetic dose （MLAD） of intrathecal ropivacaine for nonobstetric patients has been reported. However, few data are available on the MLAD of hyperbaric ropivacine for obstetric patients and the relative potency to bupivacaine has not been fully determined. In this study, we sought to determine the MLAD of intrathecal ropivacaine and bupivacaine for elective cesarean section and to define their relative potency ratio.Methods We enrolled forty parturients undergoing elective cesarean section under combined spinal-epidural anesthesia and randomized them to one of two groups to receive intrathecal 0.5% hyperbaric ropivacaine or bupivacaine.The initial dose was 10 mg, and was increased in increments of 1 mg, using the technique of up-down sequential allocation. Efficacy was accepted if adequate sensory dermatomal anesthesia to pin prick to T7 or higher was attained within 20 minutes after intrathecal injection, and required no supplementary epidural injection for procedure until at least 50 minutes after the intrathecal injection.Results The intrathecal MLAD was 9.45 mg （95%confidence interval （CI）, 8.45-10.56 mg） for ropivacaine and 7.53 mg （95%CI, 7.00-8.10 mg） for bupivacaine. The relative potency ratio was 0.80 （95% Cl, 0.74-0.85） for ropivacaine/bupivacaine when given intrathecally in cesarean section.Conclusion Ropivacaine is 20% less potent than bupivacaine during intrathecal anesthesia for cesarean delivery.展开更多
Based on the high frequency （HF） integrated radar cross section （RCS） calculation approach, a technique of detecting major scattering source is developed by using an appropriate arithmetic for scattering distribut...Based on the high frequency （HF） integrated radar cross section （RCS） calculation approach, a technique of detecting major scattering source is developed by using an appropriate arithmetic for scattering distribution and scattering source detection. For the perfect adaptability to targets and the HF of the HF integrated RCS calculation platform, this technique is suitable to solve large complex targets and has lower requirement to the target modeling. A comparison with the result of 2-D radar imaging confirms the accuracy and reliability of this technique in recognition of the major scattering source on complex targets. This technique provides the foundation for rapid integrated evaluation of the scattering performance and 3-D scattering model reconstruction of large complex targets.展开更多
Objective:The morphology analysis of whole-mount mouse embryos was observed using an improved paraffin section technique.Methods:Mouse embryos of varying embryonic ages were collected and whole-mount embryo paraffin s...Objective:The morphology analysis of whole-mount mouse embryos was observed using an improved paraffin section technique.Methods:Mouse embryos of varying embryonic ages were collected and whole-mount embryo paraffin sections were prepared using PFA-intravenously injected fixation,prolonged dehydration,and paraffin embedding.Hematoxylin and eosin(H&E)staining and immunohistochemical staining were employed to evaluate the quality of sections,with different tissues being observed labeled by CD34.Results:Following a series of tissue processing and staining procedures,the structure of the whole-mount mouse embryo was well-preserved,and the staining was clear and easily distinguishable.Embryos of different embryonic ages were treated differently,yet the quality of tissue processing remained highly consistent.Conclusion:Tissue processing and staining have been significantly improved,allowing for the easy acquisition of whole-mount mouse embryos of different ages through simplified methods of tissue fixation and dehydration duration.The staining results are clear and stable,providing technical support for the study of mouse embryo development.展开更多
文摘Background Intrathecal anesthesia is commonly used for cesarean section. Bupivacaine and ropivacaine have all been used as intrathecal drugs. The minimum effective local anesthetic dose （MLAD） of intrathecal ropivacaine for nonobstetric patients has been reported. However, few data are available on the MLAD of hyperbaric ropivacine for obstetric patients and the relative potency to bupivacaine has not been fully determined. In this study, we sought to determine the MLAD of intrathecal ropivacaine and bupivacaine for elective cesarean section and to define their relative potency ratio.Methods We enrolled forty parturients undergoing elective cesarean section under combined spinal-epidural anesthesia and randomized them to one of two groups to receive intrathecal 0.5% hyperbaric ropivacaine or bupivacaine.The initial dose was 10 mg, and was increased in increments of 1 mg, using the technique of up-down sequential allocation. Efficacy was accepted if adequate sensory dermatomal anesthesia to pin prick to T7 or higher was attained within 20 minutes after intrathecal injection, and required no supplementary epidural injection for procedure until at least 50 minutes after the intrathecal injection.Results The intrathecal MLAD was 9.45 mg （95%confidence interval （CI）, 8.45-10.56 mg） for ropivacaine and 7.53 mg （95%CI, 7.00-8.10 mg） for bupivacaine. The relative potency ratio was 0.80 （95% Cl, 0.74-0.85） for ropivacaine/bupivacaine when given intrathecally in cesarean section.Conclusion Ropivacaine is 20% less potent than bupivacaine during intrathecal anesthesia for cesarean delivery.
基金supported by the National Natural Science Foundation of China (Grant No.90305026)
文摘Based on the high frequency （HF） integrated radar cross section （RCS） calculation approach, a technique of detecting major scattering source is developed by using an appropriate arithmetic for scattering distribution and scattering source detection. For the perfect adaptability to targets and the HF of the HF integrated RCS calculation platform, this technique is suitable to solve large complex targets and has lower requirement to the target modeling. A comparison with the result of 2-D radar imaging confirms the accuracy and reliability of this technique in recognition of the major scattering source on complex targets. This technique provides the foundation for rapid integrated evaluation of the scattering performance and 3-D scattering model reconstruction of large complex targets.
基金the funding of Department of Education of Guangdong Province,China(Grant No.2020KTSCX036Grant No.2023A1515010544)Health Commission of Guangdong Province(A2023342).
文摘Objective:The morphology analysis of whole-mount mouse embryos was observed using an improved paraffin section technique.Methods:Mouse embryos of varying embryonic ages were collected and whole-mount embryo paraffin sections were prepared using PFA-intravenously injected fixation,prolonged dehydration,and paraffin embedding.Hematoxylin and eosin(H&E)staining and immunohistochemical staining were employed to evaluate the quality of sections,with different tissues being observed labeled by CD34.Results:Following a series of tissue processing and staining procedures,the structure of the whole-mount mouse embryo was well-preserved,and the staining was clear and easily distinguishable.Embryos of different embryonic ages were treated differently,yet the quality of tissue processing remained highly consistent.Conclusion:Tissue processing and staining have been significantly improved,allowing for the easy acquisition of whole-mount mouse embryos of different ages through simplified methods of tissue fixation and dehydration duration.The staining results are clear and stable,providing technical support for the study of mouse embryo development.
