[目的]探讨经皮椎体成形术中骨水泥在椎体内分布范围对临床疗效的影响。[方法]对2013年6月-2014年6月确诊为骨质疏松性压缩性骨折并行经皮椎体成形术治疗的60例患者进行回顾性研究,参照术后X线片或CT重建判断骨水泥在椎体内的分布情况,...[目的]探讨经皮椎体成形术中骨水泥在椎体内分布范围对临床疗效的影响。[方法]对2013年6月-2014年6月确诊为骨质疏松性压缩性骨折并行经皮椎体成形术治疗的60例患者进行回顾性研究,参照术后X线片或CT重建判断骨水泥在椎体内的分布情况,将患者分为3组,A组：骨水泥没有弥散于骨折线区域;B组：骨水泥仅弥散于骨折线区域;C组：骨水泥弥散于整个椎体。记录术前、术后第3 d、术后3、6个月时的疼痛视觉模拟疼痛评分（VAS）及Oswestry功能障碍指数（ODI）评分,对3组患者不同时间点的疼痛程度及个人生活情况进行比较分析。[结果]所有患者均顺利完成手术,无严重并发症发生。术中骨水泥注射量为3.5-6.0 ml,平均（4.7±0.8）ml。3组患者术后疼痛及生活质量明显改善,术后第3 d,第3、6个月VAS评分及ODI与术前相比,差异有统计学意义（P〈0.05）。A组和B、C组患者术后3 d VAS评分及ODI分别对比差异均有统计学差异（P〈0.05）,B、C组患者术后第3 d VAS评分及ODI对比,差异无统计学意义（P〉0.05）,3组患者术后3、6个月VAS评分及ODI分别比较,差异均无统计学意义（P〉0.05）。B、C两组患者术后即时疗效较A组明显,随访3个月后3组患者疗效差异不明显。[结论]骨质疏松性压缩性骨折患者行经皮椎体成形术后,在疼痛及生活质量上均有明显改善,椎体内骨水泥是否弥散于骨折线区域可能是影响椎体成形术疗效的因素之一。展开更多
Roof greening can increase areas of green and improve ecological environment in city.Based on roof greening in low energy demo building of Tsinghua University,This paper analyses the temperature distributed character ...Roof greening can increase areas of green and improve ecological environment in city.Based on roof greening in low energy demo building of Tsinghua University,This paper analyses the temperature distributed character and ecological effect of roof greening.The result show that roof greening can adjust the microclimate.The cool effect of vegetation roof is very distinctness at 12:00 to 16:00.It decrease temperature 4 ℃ and reduce the duration time of high temperature in summer,with seasonal variation,the cool effect is decreased.The temperature distribution in autumn is similar with summer.The preserve heat in winter is not obvious than the cool effect in summer.The mean temperature on vegetation roof is higher than cement roof,and the effect is an accumulative process.The thermal distributions is important to relation of roof greening and environment,it can provide scientific basis for the construction and development of roof greening.展开更多
The low field nuclear magnetic resonance (NMR), as a nondestructive and noninvasive technique, was employed to investigate the water distribution and content in cement paste with different water-to-cement ratio (w/c r...The low field nuclear magnetic resonance (NMR), as a nondestructive and noninvasive technique, was employed to investigate the water distribution and content in cement paste with different water-to-cement ratio (w/c ratio) during early and later hydration stages. From the water distribution spectrum deduced from relaxation time distribution in paste, it is suggested that the water fills in the capillary pores at initial period, and then diffuses to the mesopores and gel pores in hydration products with the hydration proceeding. The decrease of peak area in water distribution spectrum reflects the transformation from physically bound water to chemically bound water. In addition, based on the connection between relaxation time and pore size, the relative content changes of water in various states and constrained in different types of pores were also measured. The results demonstrate that it is influenced by the formation of pore system and the original water-to-cement ratio in the paste. Consequently, the relative content of capillary water is dropped to less than 2% in the paste with low w/c ratio of 0.3 when being hydrated for 1 d, while the contents are still 16% and 36% in the pastes with w/c ratios of 0.4 and 0.5, respectively.展开更多
文摘[目的]探讨经皮椎体成形术中骨水泥在椎体内分布范围对临床疗效的影响。[方法]对2013年6月-2014年6月确诊为骨质疏松性压缩性骨折并行经皮椎体成形术治疗的60例患者进行回顾性研究,参照术后X线片或CT重建判断骨水泥在椎体内的分布情况,将患者分为3组,A组：骨水泥没有弥散于骨折线区域;B组：骨水泥仅弥散于骨折线区域;C组：骨水泥弥散于整个椎体。记录术前、术后第3 d、术后3、6个月时的疼痛视觉模拟疼痛评分（VAS）及Oswestry功能障碍指数（ODI）评分,对3组患者不同时间点的疼痛程度及个人生活情况进行比较分析。[结果]所有患者均顺利完成手术,无严重并发症发生。术中骨水泥注射量为3.5-6.0 ml,平均（4.7±0.8）ml。3组患者术后疼痛及生活质量明显改善,术后第3 d,第3、6个月VAS评分及ODI与术前相比,差异有统计学意义（P〈0.05）。A组和B、C组患者术后3 d VAS评分及ODI分别对比差异均有统计学差异（P〈0.05）,B、C组患者术后第3 d VAS评分及ODI对比,差异无统计学意义（P〉0.05）,3组患者术后3、6个月VAS评分及ODI分别比较,差异均无统计学意义（P〉0.05）。B、C两组患者术后即时疗效较A组明显,随访3个月后3组患者疗效差异不明显。[结论]骨质疏松性压缩性骨折患者行经皮椎体成形术后,在疼痛及生活质量上均有明显改善,椎体内骨水泥是否弥散于骨折线区域可能是影响椎体成形术疗效的因素之一。
文摘Roof greening can increase areas of green and improve ecological environment in city.Based on roof greening in low energy demo building of Tsinghua University,This paper analyses the temperature distributed character and ecological effect of roof greening.The result show that roof greening can adjust the microclimate.The cool effect of vegetation roof is very distinctness at 12:00 to 16:00.It decrease temperature 4 ℃ and reduce the duration time of high temperature in summer,with seasonal variation,the cool effect is decreased.The temperature distribution in autumn is similar with summer.The preserve heat in winter is not obvious than the cool effect in summer.The mean temperature on vegetation roof is higher than cement roof,and the effect is an accumulative process.The thermal distributions is important to relation of roof greening and environment,it can provide scientific basis for the construction and development of roof greening.
基金Project(2009CB623105) supported by the National Basic Research Program of ChinaProject(51108341) supported by the National Natural Science Foundation of ChinaProjects(20110490703, 2012T50437) supported by China Postdoctoral Science Foundation
文摘The low field nuclear magnetic resonance (NMR), as a nondestructive and noninvasive technique, was employed to investigate the water distribution and content in cement paste with different water-to-cement ratio (w/c ratio) during early and later hydration stages. From the water distribution spectrum deduced from relaxation time distribution in paste, it is suggested that the water fills in the capillary pores at initial period, and then diffuses to the mesopores and gel pores in hydration products with the hydration proceeding. The decrease of peak area in water distribution spectrum reflects the transformation from physically bound water to chemically bound water. In addition, based on the connection between relaxation time and pore size, the relative content changes of water in various states and constrained in different types of pores were also measured. The results demonstrate that it is influenced by the formation of pore system and the original water-to-cement ratio in the paste. Consequently, the relative content of capillary water is dropped to less than 2% in the paste with low w/c ratio of 0.3 when being hydrated for 1 d, while the contents are still 16% and 36% in the pastes with w/c ratios of 0.4 and 0.5, respectively.
