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81.
顶空气相色谱法测定盐酸依匹斯汀中溶剂残留 总被引:26,自引:3,他引:26
建立顶空气相色谱法分析盐酸依匹斯汀中溶剂残留.采用DB-1大口径毛细管柱,以正丙醇为内标进行定量.甲醇、乙醚、三氯甲烷、四氢呋喃的线性范围分别为7.9 ~ 317.0μg·ml-1 (r=0.9996),0.7~35.5μg·ml-1(r=0.9998),1.5~73.5μg·ml-1 (r=0.9992),0.9~44.4μg·ml-1(r=0.9994),回收率分别为101.64%,97.18%,99.32%,101.12%,RSD分别为1.97%,1.10%,2.40%,0.84%.本方法简单、准确、灵敏度高、重现性好. 相似文献
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Dongping Chen Zhaobing Su Linsheng Weng Longbin Cao Can Chen Sufen Zeng 《Journal of biomaterials science. Polymer edition》2013,24(15):1909-1919
AbstractAs a promising candidate, biodegradable Poly-L-lactic Acid (PLLA) has been extensively used in coronary artery stents. In our previous reports, PLLA stents implanted in porcine coronary arteries showed safety without stent thrombosis. However, inflammatory responses were observed, which needed further study. In this study, human aortic endothelial cells (HAEC) were treated with different volume percentages of extract of pre-degraded PLLA (extract of PLLA) in vitro, and the cell growth curve and morphological changes were examined. The expression of inflammatory cytokines such as NF-κB, VEGF and VCAM-1 were also observed by ELISA. In addition, PLLA stent was implanted in porcine coronary artery to examine morphological changes, functional marker eNOS and inflammatory responses. The extract of PLLA caused significant growth inhibition and release of NF-κB, VEGF and VCAM-1 in HAEC with volume percentage-dependence. Although re-endothelialization and expression of eNOS was observed, expression of NF-κB and lymphocytes surrounding PLLA were also found after PLLA stents were implanted in the artery. This study demonstrated the effects of inflammation on endothelial cells induced by PLLA degradation in vitro and showed the inflammation in vivo, suggesting that anti-inflammatory strategy is necessary for PLLA stent implantation in the artery. 相似文献
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Cajal间质细胞(interstitial cells of Cajal,ICC)是一类主要分布于胃肠道的间质细胞,是胃肠道的起搏细胞(pacemaker cell)和信号传导细胞,与肌细胞以及末梢神经元有着紧密的关系,具有激发和促进胃肠蠕动的作用.借助于电子显微镜技术,清楚观察到了ICC位置分布和内部精细结构;应用免疫荧光等生化技术,发现了其特殊表达的C-kit蛋白;利用电生理技术,得知多种胃肠动力障碍疾病也与其异常有关.多年来,学者逐渐在胃肠道、胆道、膀胱、子宫等部位发现了ICC的踪迹,并试图阐述其与某些疾病的发生机制.本文就ICC的起源、形态学、受体和功能、以及与其相关的疾病等作一综述. 相似文献
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Jae Hyun Kim Casey N Ta Cong Liu Cynthia Sung Alex M Butler Latoya A Stewart Lyudmila Ena James R Rogers Junghwan Lee Anna Ostropolets Patrick B Ryan Hao Liu Shing M Lee Mitchell S V Elkind Chunhua Weng 《J Am Med Inform Assoc》2021,28(1):14
ObjectiveThis research aims to evaluate the impact of eligibility criteria on recruitment and observable clinical outcomes of COVID-19 clinical trials using electronic health record (EHR) data.Materials and MethodsOn June 18, 2020, we identified frequently used eligibility criteria from all the interventional COVID-19 trials in ClinicalTrials.gov (n = 288), including age, pregnancy, oxygen saturation, alanine/aspartate aminotransferase, platelets, and estimated glomerular filtration rate. We applied the frequently used criteria to the EHR data of COVID-19 patients in Columbia University Irving Medical Center (CUIMC) (March 2020–June 2020) and evaluated their impact on patient accrual and the occurrence of a composite endpoint of mechanical ventilation, tracheostomy, and in-hospital death.ResultsThere were 3251 patients diagnosed with COVID-19 from the CUIMC EHR included in the analysis. The median follow-up period was 10 days (interquartile range 4–28 days). The composite events occurred in 18.1% (n = 587) of the COVID-19 cohort during the follow-up. In a hypothetical trial with common eligibility criteria, 33.6% (690/2051) were eligible among patients with evaluable data and 22.2% (153/690) had the composite event.DiscussionBy adjusting the thresholds of common eligibility criteria based on the characteristics of COVID-19 patients, we could observe more composite events from fewer patients.ConclusionsThis research demonstrated the potential of using the EHR data of COVID-19 patients to inform the selection of eligibility criteria and their thresholds, supporting data-driven optimization of participant selection towards improved statistical power of COVID-19 trials. 相似文献
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Eugen Dhimolea Ricardo de Matos Simoes Dhvanir Kansara Aziz Al’Khafaji Juliette Bouyssou Xiang Weng Shruti Sharma Joseline Raja Pallavi Awate Ryosuke Shirasaki Huihui Tang Brian J. Glassner Zhiyi Liu Dong Gao Jordan Bryan Samantha Bender Jennifer Roth Michal Scheffer Constantine S. Mitsiades 《Cancer cell》2021,39(2):240-256.e11
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目的 构建个性化知识图谱技术和定性访谈法结合,进一步挖掘张忠德教授辨治间质性肺疾病临证特征与用药规律。方法 采用回顾性分析,系统收集张忠德教授广东省中医院门诊2010年8月至2020年8月治疗间质性肺疾病病历,按照诊断标准、纳入标准、排除标准,严格筛选后,通过广东省中医院大数据挖掘团队中医药大数据智能处理与知识服务系统进行数据挖掘分析,并通过多元化视觉定性访谈法,将定量与定性分析有效结合。结果 共筛选出347首方,共141味药物,常用药物频次 ≥ 84次的药物有10味,其中党参、麦芽、黄芪、紫菀、白术等为核心用药,通过症状与药物推理知识地图显示,党参、炒麦芽、黄芪、大枣、太子参、山萸肉、巴戟天等为主要治疗用药;临证遣方用药知识关联分析,得知咳嗽、耳鸣、心悸、水肿、头痛、胸闷、恶寒等为多见,针对咳嗽,首选紫苏子、橘红、桂枝等温肺降气通阳之品等;频繁聚集显示,常用药对炒麦芽-炒白术、黄芪-党参、黄精-菟丝子、前胡-紫菀、炙枇杷叶-浙贝母等;聚类分析结果得到4组关系密切的聚类新药物组合;以脾为中轴,肺肾共扶为主的“平调五脏论”,分期阶梯辨治间质性肺疾病。结论 张忠德教授认为间质性肺疾病,虚实夹杂为多见,应从肺、脾、肾着手,采用平调五脏论分期阶梯辨治,用药配伍精简,以和为贵,以平为期。 相似文献