A new type of crown ether cross-linked chitosan was synthesized by the reaction of chitosan with 4,4’-dibromodibenzo-18-crown-6 (Br-DBC). Its token structure was analyzed with FT-IR and NMR and the adsorption behavio...A new type of crown ether cross-linked chitosan was synthesized by the reaction of chitosan with 4,4’-dibromodibenzo-18-crown-6 (Br-DBC). Its token structure was analyzed with FT-IR and NMR and the adsorption behaviors for lead and cadmium in environmental water samples by FAAS were studied. In addition the best analysis conditions were discussed and the adsorption mechanism was explained. As the enrichment factor is above 100, both recoveries are 94%-106%, the detection limits of lead and cadmium are 0.5 μg·L -1and 0.04 μg·L -1 and the relatively standard deviations of lead and cadmium are 3.1% and 2.8% respectively, this new method was successfully applied to the determination of environmental water samples. This method is fast and simple and it greatly enhances the determination ability of FAAS for lead and cadmium.展开更多
大便失禁及排便障碍等肛直肠功能性疾病在临床上十分常见,单纯依靠症状的诊断准确率不高,熟练应用肛门直肠功能检测显得较为重要。目前临床上对于各检测方法的认识和应用尚不统一,国际肛直肠生理工作组(the international anorectal phy...大便失禁及排便障碍等肛直肠功能性疾病在临床上十分常见,单纯依靠症状的诊断准确率不高,熟练应用肛门直肠功能检测显得较为重要。目前临床上对于各检测方法的认识和应用尚不统一,国际肛直肠生理工作组(the international anorectal physiology working group,IAPWG)分别于2018和2019年颁布了《肛门直肠功能评估进展》共识意见和《肛门直肠功能障碍的标准化检测方案和伦敦分型》(简称《伦敦共识》),旨在提供各肛直肠检测方法的适应证、操作流程、临床应用、优势及局限性,并在客观检查的基础上对肛门直肠功能障碍进行了分型。IAPWG提出,肛门直肠测压主要用于评估肛门运动功能,肛内超声适用于评估肛门结构,肛直肠感觉运动检测包括球囊扩张试验等,球囊逼出试验、排粪造影则为常见的两项排便试验。单项检测尚不能完全明确大便失禁或排便障碍的原因,需综合评估患者的肛门直肠结构、感觉及运动功能。患者的异常检测结果主要包括直肠肛门抑制反射消失、肛门张力和收缩力降低、直肠低敏感和高敏感。肛门直肠功能障碍的伦敦分型主要包括4个部分:①直肠肛门抑制反射异常;②肛门张力及收缩力异常;③肛门直肠协调障碍;④直肠感觉异常。《伦敦共识》可以为肛门直肠功能检测的操作方法和结果阐释提供依据,有助于检测流程的标准化和检测结果的规范化。展开更多
文摘A new type of crown ether cross-linked chitosan was synthesized by the reaction of chitosan with 4,4’-dibromodibenzo-18-crown-6 (Br-DBC). Its token structure was analyzed with FT-IR and NMR and the adsorption behaviors for lead and cadmium in environmental water samples by FAAS were studied. In addition the best analysis conditions were discussed and the adsorption mechanism was explained. As the enrichment factor is above 100, both recoveries are 94%-106%, the detection limits of lead and cadmium are 0.5 μg·L -1and 0.04 μg·L -1 and the relatively standard deviations of lead and cadmium are 3.1% and 2.8% respectively, this new method was successfully applied to the determination of environmental water samples. This method is fast and simple and it greatly enhances the determination ability of FAAS for lead and cadmium.
文摘大便失禁及排便障碍等肛直肠功能性疾病在临床上十分常见,单纯依靠症状的诊断准确率不高,熟练应用肛门直肠功能检测显得较为重要。目前临床上对于各检测方法的认识和应用尚不统一,国际肛直肠生理工作组(the international anorectal physiology working group,IAPWG)分别于2018和2019年颁布了《肛门直肠功能评估进展》共识意见和《肛门直肠功能障碍的标准化检测方案和伦敦分型》(简称《伦敦共识》),旨在提供各肛直肠检测方法的适应证、操作流程、临床应用、优势及局限性,并在客观检查的基础上对肛门直肠功能障碍进行了分型。IAPWG提出,肛门直肠测压主要用于评估肛门运动功能,肛内超声适用于评估肛门结构,肛直肠感觉运动检测包括球囊扩张试验等,球囊逼出试验、排粪造影则为常见的两项排便试验。单项检测尚不能完全明确大便失禁或排便障碍的原因,需综合评估患者的肛门直肠结构、感觉及运动功能。患者的异常检测结果主要包括直肠肛门抑制反射消失、肛门张力和收缩力降低、直肠低敏感和高敏感。肛门直肠功能障碍的伦敦分型主要包括4个部分:①直肠肛门抑制反射异常;②肛门张力及收缩力异常;③肛门直肠协调障碍;④直肠感觉异常。《伦敦共识》可以为肛门直肠功能检测的操作方法和结果阐释提供依据,有助于检测流程的标准化和检测结果的规范化。
