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91.
目的:探讨OCTA检查在视网膜静脉阻塞诊疗中的重要应用价值。
方法:采用回顾性病例对照研究,选取2018-01/10于大连市第三人民医院眼科门诊确诊为视网膜静脉阻塞的患者38例38眼,其患病眼为A组,对侧健康眼为B组。所有患者均接受OCTA对黄斑区视网膜行3mm×3mm范围的模式扫描,获得表层视网膜、深层视网膜、外层视网膜及脉络膜毛细血管层4个层面黄斑血流密度图,测量表层视网膜中心凹无血管区面积(FAZ),Image J软件计算4个层面黄斑区血流密度(MVD),OCT模式测量黄斑中心凹的水平厚度与垂直厚度(CFT)。
结果:A组和B组浅层视网膜FAZ、水平CFT及垂直CFT测量均有差异(P<0.01)。A组和B组表层视网膜及深层视网MVD均有差异(P<0.01),外层视网膜层MVD、脉络膜毛细血管层MVD结果无差异(P=0.542、0.489)。BCVA(LogMAR)分别与表层视网膜FAZ、水平CFT及垂直CFT呈正相关(r=0.482、0.652、0.621,均P<0.01),与表层视网膜MVD及深层视网膜MVD呈负相关(r=-0.486、-0.465,均P<0.01)。
结论:应用OCTA检查对提示视网膜静脉阻塞患者黄斑区视网膜的微循环障碍和视力预后有重要指导意义。 相似文献
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Li-Jun Deng Yan-Lin Wu Xian-Hua He Ke-Nan Xie 《Journal of biomaterials science. Polymer edition》2013,24(18):2237-2251
AbstractA strategy developed for obtaining positive cellular responses remains to be focused in the filed of functional biomimetics. In this study, a hydrogel covered simvastatin-loaded polyetheretherketone (PEEK) bio-composites was constructed with the purpose of bone tissue regeneration therapy. Briefly, a three-dimensional (3D) porous structure was fabricated on PEEK surface; then the substrate was functionalized with the poly(L-lactic acid)/simvastatin porous film and hyaluronic acid hydrogel subsequently. In vitro cell attachment, proliferation, and cytoskeletal observation experiments reveal that our scaffolds show better bio-affinity due to the layer of hyaluronic acid hydrogel compared with control. Furthermore, the alkaline phosphatase activity, calcium mineral deposition evaluation, and gene expression for osteogenic potential all exhibit that the superior osteogenic differentiation of MC3T3-E1 pre-osteoblasts on our scaffolds. Therefore, our PEEK samples loaded with simvastatin and covered with hyaluronic acid hydrogel hold great potential in clinical applications for bone repair. 相似文献
95.
Wen-Ni He Jun-Gui Dai Li-Jun Wu De-An Guo 《Journal of Asian natural products research》2013,15(9):760-764
Asiatic acid is a major pentacyclic triterpene isolated from Centella asiatica. It shows a variety of bioactivities. In order to obtain its derivatives, potentially useful for detailed pharmacological studies, the substrate was subjected to incubations with selected micro-organisms. In this work, asiatic acid was converted into three new compounds: 2α,3β,23,30-tetrahydroxyurs-12-ene-28-oic acid (1), 2α,3β,22β,23-tetrahydroxyurs-12-ene-28-oic acid (2), and 2α,3β,22β,23,30-pentahydroxyurs-12-ene-28-oic acid (3) by the fungus Alternaria longipes AS 3.2875. The structures of the three metabolites were determined by 1D and 2D NMR spectral data. 相似文献
96.
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
99.
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