A new triterpenoid, methyl buergericate (12a), which was elucidated as 2 alpha, 3 alpha, 19 alpha, 24-tetrahydroxyl olean-12-en-28-oic acid methyl ester by spectroscopic methods, together with eleven known triterpenoi...A new triterpenoid, methyl buergericate (12a), which was elucidated as 2 alpha, 3 alpha, 19 alpha, 24-tetrahydroxyl olean-12-en-28-oic acid methyl ester by spectroscopic methods, together with eleven known triterpenoids was isolated from Rubus buergeri Miq. The isolation of the above chemical constituents from this plant was reported for the first time.展开更多
目的应用锥形束CT实时在线校正宫颈癌调强放疗的摆位误差,确定宫颈癌患者外照射治疗计划中外扩边界值的范围,并分析体质量差别对摆位的影响。方法调强放疗的宫颈癌患者按体质量指数(body mass index,BMI)分为A组(BMI≥24)和B组(BMI<2...目的应用锥形束CT实时在线校正宫颈癌调强放疗的摆位误差,确定宫颈癌患者外照射治疗计划中外扩边界值的范围,并分析体质量差别对摆位的影响。方法调强放疗的宫颈癌患者按体质量指数(body mass index,BMI)分为A组(BMI≥24)和B组(BMI<24),将所获得锥形束CT(cone-beam com-puter tomography,CBCT)与计划CT图像进行灰度自动配准,计算摆位误差并进行在线评价。结果 37例患者在X轴(左右)、Y轴(头脚)、Z轴(前后)方向摆位误差分别为(1.1±2.3)、(2.1±5.0)、(-1.1±2.2)mm,外扩边界分别为5.2、11.0、5.6mm。A组患者在Y轴方向摆位误差较B组增大,差异有统计学意义(P<0.05)。而两组在X轴、Z轴方向差异无统计学意义(P>0.05)。结论应用锥形束CT在线校正可减小宫颈癌患者摆位误差、提高放疗的精确性,可利用摆位误差估算放疗摆位外扩边界值。体质量指数大者应适当增加外扩边界。展开更多
文摘A new triterpenoid, methyl buergericate (12a), which was elucidated as 2 alpha, 3 alpha, 19 alpha, 24-tetrahydroxyl olean-12-en-28-oic acid methyl ester by spectroscopic methods, together with eleven known triterpenoids was isolated from Rubus buergeri Miq. The isolation of the above chemical constituents from this plant was reported for the first time.
