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P-aminobenzoic acid promotes retinal regeneration through activation of Ascl1a in zebrafish 被引量:1
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作者 Meihui He Mingfang Xia +3 位作者 Qian Yang Xingyi Chen Haibo Li Xiaobo Xia 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第8期1849-1856,共8页
The retina of zebrafish can regenerate completely after injury.M ultiple studies have demonstrated that metabolic alte rations occur during retinal damage;however to date no study has identified a link between metabol... The retina of zebrafish can regenerate completely after injury.M ultiple studies have demonstrated that metabolic alte rations occur during retinal damage;however to date no study has identified a link between metabolites and retinal regeneration of zebrafish.Here,we performed an unbiased metabolome sequencing in the N-methyl-D-aspartic acid-damaged retinas of zebrafish to demonstrate the metabolomic mechanism of retinal regeneration.Among the differentially-ex pressed metabolites,we found a significant decrease in p-aminobenzoic acid in the N-methyl-D-aspartic acid-damaged retinas of zebrafish.Then,we investigated the role of p-aminobenzoic acid in retinal regeneration in adult zebrafish.Impo rtantly,p-aminobenzoic acid activated Achaetescute complex-like 1a expression,thereby promoting Müller glia reprogramming and division,as well as Müller glia-derived progenitor cell proliferation.Finally,we eliminated folic acid and inflammation as downstream effectors of PABA and demonstrated that PABA had little effect on Müller glia distribution.Taken together,these findings show that PABA contributes to retinal regeneration through activation of Achaetescute complex-like 1a expression in the N-methyl-Daspartic acid-damaged retinas of zebrafish. 展开更多
关键词 Achaetescute complex-like 1a(Ascl1a) metabolomics müller glia p-aminobenzoic acid(PABA) RETINA REGENERATION ZEBRAFISH
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PMIA树脂溶液中盐酸含量的测定
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作者 杨娜 宋志成 +3 位作者 丁新艳 王进 刘国钧 曹凯凯 《合成纤维工业》 CAS 2024年第1期90-95,共6页
分别以乙酸钠-甲醇溶液、氢氧化钾-甲醇溶液为滴定剂,采用电位滴定法测定不同中和程度的聚间苯二甲酰间苯二胺(PMIA)树脂溶液中盐酸含量,并对2种测试方法的准确度和精密度进行比较。结果表明:采用2种测试方法测定中和程度分别为0、60%、... 分别以乙酸钠-甲醇溶液、氢氧化钾-甲醇溶液为滴定剂,采用电位滴定法测定不同中和程度的聚间苯二甲酰间苯二胺(PMIA)树脂溶液中盐酸含量,并对2种测试方法的准确度和精密度进行比较。结果表明:采用2种测试方法测定中和程度分别为0、60%、95%、100%的PMIA树脂溶液中盐酸含量,2种测试方法的测定结果相近;采用F检验和t检验两种统计法验证了显著性水平为0.05、置信度为95%时2种测试方法的准确度和精密度均无显著差异,以氢氧化钾-甲醇溶液为滴定剂的测试方法的精密度更高;采用标准盐酸加入法,并以氢氧化钾-甲醇溶液为滴定剂测定不同中和程度的PMIA树脂溶液中盐酸回收率,平均回收率为96.5%~98.5%,验证了该方法的准确性;对于正常滴定过程中等当点不易识别的PMIA树脂溶液,可通过预加已知量的盐酸后再采用氢氧化钾-甲醇溶液滴定,从而确定溶液的酸碱性。 展开更多
关键词 聚间苯二甲酰间苯二胺溶液 中和程度 盐酸含量 电位滴定法
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4种消除M蛋白对血清尿酸检测干扰的方法比较分析
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作者 许冬 孟涛 +1 位作者 陈剑 李海霞 《临床检验杂志》 CAS 2024年第10期728-732,共5页
目的比较稀释法、聚乙二醇(PEG)沉淀法、超滤膜过滤法和手工计算法4种方法在清除M蛋白干扰尿酸检测中的差异,评估其在临床应用中的价值。方法对受M蛋白干扰的血清标本分别采用稀释法(去离子水和生理盐水)、PEG沉淀法、超滤膜过滤法和手... 目的比较稀释法、聚乙二醇(PEG)沉淀法、超滤膜过滤法和手工计算法4种方法在清除M蛋白干扰尿酸检测中的差异,评估其在临床应用中的价值。方法对受M蛋白干扰的血清标本分别采用稀释法(去离子水和生理盐水)、PEG沉淀法、超滤膜过滤法和手工计算法进行尿酸检测和计算,以超滤膜过滤法的结果为参考值,比较4种清除M蛋白干扰的方法的价值。结果稀释法中,去离子水和生理盐水不同倍数稀释后结果与超滤法结果的相对偏倚分别为:3倍稀释-32.38%、-60.66%,5倍稀释-26.23%、-46.72%,10倍稀释-22.13%、-30.33%。PEG沉淀法与超滤法的相对偏倚为-3.28%,10例对照样本PEG沉淀前后的偏倚在-3.80%~2.34%之间。超滤膜过滤法的结果与患者原始结果相对偏倚为687.10%。手工计算法与PEG沉淀法和超滤膜过滤法的偏倚分别为-1.64%和1.69%,10例对照样本偏倚在-4.62%~0%之间。结论4种清除M蛋白干扰尿酸检测的方法在准确性、便捷性、经济性和实用性方面各有优劣。PEG沉淀法和超滤膜过滤法检测的准确度最高,但操作较繁琐,耗材成本较高。稀释法操作简单,实用性、经济性较好,但准确度较差。手工计算法需要对尿酸的检测参数及仪器检测原理有较好的掌握,其计算结果与超滤膜过滤法接近,方便经济快捷,可作为临床常规方法。 展开更多
关键词 m蛋白 尿酸 干扰 消除方法
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基于药效团模型筛选CTX-M-14型超广谱β-内酰胺酶抑制剂
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作者 王梦帆 赵子玉 +3 位作者 王春光 刘廷玉 陈曦 张铁 《生物技术通报》 CAS CSCD 北大核心 2024年第6期319-329,共11页
【目的】开发针对头孢噻肟-水解酶-14(CTX-M-14)型超广谱β-内酰胺酶(extended-spectrumβ-lactamase,ESBLs)的抑制剂,用以缓解细菌耐药带来的严重危害。【方法】使用DiscoveryStudio Visualizer(DS Visualizer)构建基于受体结构的药效... 【目的】开发针对头孢噻肟-水解酶-14(CTX-M-14)型超广谱β-内酰胺酶(extended-spectrumβ-lactamase,ESBLs)的抑制剂,用以缓解细菌耐药带来的严重危害。【方法】使用DiscoveryStudio Visualizer(DS Visualizer)构建基于受体结构的药效团模型(structure-based pharmacophore,SBP)和基于配体共同特征的定性药效团模型(common feature pharmacophore generation,HIPHOP),并将验证后的模型作为查询条件对ZINC数据库进行以CTX-M-14蛋白为靶标的虚拟筛选,得到拟合分数良好的中药单体成分甘草酸(glycyrrhizic acid,GL),对其进行相关作用力分析、分子动力学模拟和结合自由能计算,分析甘草酸与CTX-M-14蛋白的结合模式、结合能力及稳定性;最后通过联合抑菌试验及酶动力学试验考察甘草酸的抗菌增敏活性、抑酶作用及抑酶方式。【结果】中药单体成分甘草酸主要与CTX-M-14蛋白活性中心多个氨基酸残基形成氢键和范德华作用力,两者的对接分数与结合自由能分别为-10 kcal/mol及-22.06 kcal/mol;甘草酸与头孢噻肟钠联用呈协同作用(FICI≤0.5);甘草酸可竞争性抑制β-内酰胺酶对底物抗生素的水解作用,对头孢噻肟钠的抑酶保护率可达58.53%,与克拉维酸接近(60.98%)。【结论】中药单体甘草酸可与CTX-M-14蛋白稳定结合,通过竞争性抑制β-内酰胺酶对底物抗生素的水解作用,提高多重耐药大肠杆菌E320和重组蛋白阳性菌BL-21对头孢噻肟钠的敏感性,实现抗生素的减量增效。 展开更多
关键词 甘草酸 CTX-m-14 药效团模型 分子动力学模拟 联合抑菌
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EB病毒IgM、IgG及DNA检测在儿童呼吸道感染性疾病中的诊断研究
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作者 张悦 季忠庶 申爽 《中国实用医药》 2024年第4期78-81,共4页
目的探析爱泼斯坦-巴尔病毒(EB病毒,EBV)免疫球蛋白(Ig)M、IgG及脱氧核糖核酸(DNA)检测在儿童呼吸道感染性疾病中的诊断价值。方法选取400例呼吸道感染性疾病患儿作为观察组,同时选取100例无呼吸道感染患儿作为对照组。对两组患儿EBV-Ig... 目的探析爱泼斯坦-巴尔病毒(EB病毒,EBV)免疫球蛋白(Ig)M、IgG及脱氧核糖核酸(DNA)检测在儿童呼吸道感染性疾病中的诊断价值。方法选取400例呼吸道感染性疾病患儿作为观察组,同时选取100例无呼吸道感染患儿作为对照组。对两组患儿EBV-IgM、EBV-IgG及EBV-DNA进行检测。比较观察组不同年龄段患儿EBV-IgM、EBV-IgG及EBV-DNA阳性率,两组EBV-IgM、EBV-IgG及EBV-DNA检测结果;分析各项指标的诊断价值。结果观察组不同年龄段患儿EBV-IgM、EBV-IgG阳性率比较,差异具有统计学意义(P<0.05);观察组不同年龄段患儿EBV-DNA阳性率比较无明显差异(P>0.05)。EBV-IgM检测中,观察组化学发光值(11.39±2.12)高于对照组的(9.54±1.35),阳性率50.50%(202/400)高于对照组的5.00%(5/100),差异有统计学意义(P<0.05);EBV-IgG检测中,观察组吸光度值(11.33±2.15)高于对照组的(9.03±1.06),阳性率58.00%(232/400)高于对照组的12.00%(12/100),差异有统计学意义(P<0.05);EBV-DNA检测中,观察组循环数Ct值(34.13±4.88)低于对照组的(43.75±11.62),阳性率57.00%(228/400)高于对照组的6.00%(6/100),差异均具有统计学意义(P<0.05)。EBV-DNA对呼吸道感染性疾病患儿的诊断价值最高[曲线下面积(AUC)=0.644],其次依次是EBV-IgM(AUC=0.618)、EBV-IgG(AUC=0.584),EBV-IgM对呼吸道感染性疾病患儿的诊断特异度最高,为96.12%。结论EBV-IgM、EBV-IgG、EBV-DNA检测在儿童呼吸道感染性疾病的诊断中具有重要的指导意义。 展开更多
关键词 爱泼斯坦-巴尔病毒 免疫球蛋白m 免疫球蛋白G 脱氧核糖核酸 儿童呼吸道感染性疾病
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Müller cells are activated in response to retinal outer nuclear layer degeneration in rats subjected to simulated weightlessness conditions
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作者 Yuxue Mu Ning Zhang +7 位作者 Dongyu Wei Guoqing Yang Lilingxuan Yao Xinyue Xu Yang Li Junhui Xue Zuoming Zhang Tao Chen 《Neural Regeneration Research》 SCIE CAS 2025年第7期2116-2128,共13页
A microgravity environment has been shown to cause ocular damage and affect visual acuity,but the underlying mechanisms remain unclear.Therefore,we established an animal model of weightlessness via tail suspension to ... A microgravity environment has been shown to cause ocular damage and affect visual acuity,but the underlying mechanisms remain unclear.Therefore,we established an animal model of weightlessness via tail suspension to examine the pathological changes and molecular mechanisms of retinal damage under microgravity.After 4 weeks of tail suspension,there were no notable alterations in retinal function and morphology,while after 8 weeks of tail suspension,significant reductions in retinal function were observed,and the outer nuclear layer was thinner,with abundant apoptotic cells.To investigate the mechanism underlying the degenerative changes that occurred in the outer nuclear layer of the retina,proteomics was used to analyze differentially expressed proteins in rat retinas after 8 weeks of tail suspension.The results showed that the expression levels of fibroblast growth factor 2(also known as basic fibroblast growth factor)and glial fibrillary acidic protein,which are closely related to Müller cell activation,were significantly upregulated.In addition,Müller cell regeneration and Müller cell gliosis were observed after 4 and 8 weeks,respectively,of simulated weightlessness.These findings indicate that Müller cells play an important regulatory role in retinal outer nuclear layer degeneration during weightlessness. 展开更多
关键词 glial fibrous acidic protein GLIOSIS müller cells nerve growth factor neural differentiation neurodegeneration proteomic retinal degeneration retinal outer nuclear layer simulated weightlessness
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如何消除血清中高IgM对尿酸、前白蛋白检测干扰的探讨
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作者 沈军 王弘明 《现代科学仪器》 2024年第1期20-22,共3页
目的:试图找出常规湿生化检测中,降低较高浓度的IgM对尿酸(UA)、前白蛋白(PA)干扰的较为便捷的方法。方法:聚乙二醇(25%PEG),去离子水(DH2O),生理盐水(0.9%NaCl),对标本进行稀释,分别使用3000rpm、10000rpm离心10分钟,取上清液检测,结... 目的:试图找出常规湿生化检测中,降低较高浓度的IgM对尿酸(UA)、前白蛋白(PA)干扰的较为便捷的方法。方法:聚乙二醇(25%PEG),去离子水(DH2O),生理盐水(0.9%NaCl),对标本进行稀释,分别使用3000rpm、10000rpm离心10分钟,取上清液检测,结果乘稀释倍数。结果:使用25%PEG或蒸馏水稀释离心可以有效消除高IgM对UA和PA的干扰,而使用生理盐水效果不好。结论:在高浓度IgM标本中使用25%PEG10000rpm、DH2O3000和10000rpm可消除其对UA、PA的检测。 展开更多
关键词 聚乙二醇 尿酸 前白蛋白 免疫球蛋白m
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复合氨基酸Amino M-10在化妆品中的应用研究
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作者 朱永闯 张玉霄 +2 位作者 赖子强 刘平波 郑丹阳 《广东轻工职业技术学院学报》 2024年第4期1-10,共10页
复合氨基酸Amino M-10是由10种氨基酸科学配比复配而成,总氨基酸浓度为7.5~8.5%。通过采用理化分析、细胞模型试验、人体功效评价试验、配方应用实例、消费者调查等多种方法,研究了复合氨基酸Amino M-10的基本性能、护肤功效、护发功效... 复合氨基酸Amino M-10是由10种氨基酸科学配比复配而成,总氨基酸浓度为7.5~8.5%。通过采用理化分析、细胞模型试验、人体功效评价试验、配方应用实例、消费者调查等多种方法,研究了复合氨基酸Amino M-10的基本性能、护肤功效、护发功效及其在洗护和护肤化妆品中的应用,研究结果显示,复合氨基酸Amino M-10具有很好的保湿、舒缓、抗氧化、抗衰老、祛红血丝、护发等功效。人体斑贴试验和细胞活力检测结果也显示复合氨基酸Amino M-10温和而无刺激,可广泛应用于洗护和护肤化妆品中,具有广阔的市场前景和研究价值。 展开更多
关键词 复合氨基酸 Amino m-10 功效 护肤 护发 应用
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m^(6)A-脂肪酸代谢相关lncRNA对结肠癌预后及免疫疗效的预测价值
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作者 沈超琴 刘韬韬 《中国临床医学》 2024年第1期68-77,共10页
目的 探讨结肠癌中m^(6)A-脂肪酸代谢相关lncRNA,并分析其与患者预后及肿瘤免疫微环境的相关性,为结肠癌患者诊治提供新的分子靶点。方法 从TCGA数据库中获取结肠癌患者的转录组数据及临床信息。通过Pearson相关分析筛选出m^(6)A-脂肪... 目的 探讨结肠癌中m^(6)A-脂肪酸代谢相关lncRNA,并分析其与患者预后及肿瘤免疫微环境的相关性,为结肠癌患者诊治提供新的分子靶点。方法 从TCGA数据库中获取结肠癌患者的转录组数据及临床信息。通过Pearson相关分析筛选出m^(6)A-脂肪酸代谢相关lncRNA。采用单因素、LASSO及多因素Cox回归分析构建基于lncRNA表达的风险模型;通过Kaplan-Meier生存曲线、ROC曲线及列线图验证风险模型的准确性。比较高风险组及低风险组结肠癌患者免疫细胞浸润情况。结果 从TCGA数据库中鉴定出670个m^(6)A相关lncRNA及1 011个脂肪酸代谢相关lncRNA,其中39个交叉的lncRNA具有预后意义。通过LASSO及多因素回归构建了包含5个m^(6)A-脂肪酸代谢相关lncRNA的风险模型,风险评分较高者预后较差。多因素Cox回归分析表明风险评分是影响患者预后的独立相关因素(HR=11.8,95%CI 3.6~38.7)。ROC曲线显示其预测患者1年、3年、5年生存率的曲线下面积分别为0.758 (95%CI 0.611~0.905)、0.793 (95%CI 0.708~0.877)和0.815 (95%CI 0.722~0.907)。相较于高风险组,低风险组肿瘤有更多的M1型巨噬细胞浸润(P<0.05),免疫检查点基因(CD44、TNFRSF9、CD40LG、CD48、CD244、IDO1、HAVCR2、CD27、ICOS、LAIR1、TMIGD2、CD28、TIGIT)表达增高(P<0.05)。结论 该m^(6)A-脂肪酸代谢相关lncRNA风险模型可用于预测结肠癌患者预后及免疫疗效。 展开更多
关键词 结肠癌 m^(6)A 脂肪酸代谢 lncRNA 免疫治疗
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Peripheral mechanism of inhibitory effect of centrally administrated histamine on gastric acid secretion 被引量:4
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作者 ZHANG Zhi Fang, WANG Zhu Li and LU Guang Qi 《World Journal of Gastroenterology》 SCIE CAS CSCD 1998年第3期42-44,共3页
AIM To study the peripheral mechanism of the inhibitory effect of intra third ventricular administration (icv) of histamine (HA) on gastric acid secretion in rats. METHODS Gastric acid was continuously washed wit... AIM To study the peripheral mechanism of the inhibitory effect of intra third ventricular administration (icv) of histamine (HA) on gastric acid secretion in rats. METHODS Gastric acid was continuously washed with 37℃ saline by a perfusion pump in male adrenalectomized SD rats. Drugs were injected intravenously (iv) by a syringe pump and their effect on pentagastrin induced (10μg·kg·h, iv) gastric acid secretion was observed. RESULTS The inhibitory effect of HA (1μg, icv) on gastric acid secretion was blocked by subdiaphragmatic vagotomy, and pretreatment with atropine (0 005mg·kg·h, iv). Pretreatment with somatostatin antagonist, cyclo [7 aminoheptanoyl Phe D Trp Lys Thr(Bzl)], ( 2μg - 4μg ·kg· 100min , iv) could also block the inhibitory effect of HA on gastric acid secretion in a dose dependent manner. CONCLUSION The inhibitory effect of centrally administrated HA on gastric acid secretion may be mediated by vagi, acetylcholine M receptor and somatostatin. 展开更多
关键词 GASTRIC acid/secretion HISTAmINE stomach/physiology SOmATOSTATIN ACETYLCHOLINE m receptor rats
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Mechanism and kinetics of iron extraction from high silica boehmite−kaolinite bauxite by hydrochloric acid leaching 被引量:5
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作者 Dmitry VALEEV Denis PANKRATOV +5 位作者 Andrei SHOPPERT Artem SOKOLOV Alexandr KASIKOV Alexandra MIKHAILOVA Cristian SALAZAR-CONCHA Ilia RODIONOV 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第10期3128-3149,共22页
The chemical and mineral compositions of bauxite recovered from the Severoonezhsk Bauxite Mine(Arkhangelsk region,Russia)were studied by XRD,ICP-OES,TG/DSC,SEM,TEM,and Mössbauer spectroscopy.The iron-containing m... The chemical and mineral compositions of bauxite recovered from the Severoonezhsk Bauxite Mine(Arkhangelsk region,Russia)were studied by XRD,ICP-OES,TG/DSC,SEM,TEM,and Mössbauer spectroscopy.The iron-containing minerals of the bauxites were found to comprise alumogoethite(α-Fe_(1−x)Al_(x)OOH),alumohematite(α-(Fe_(1−x)Al_(x))_(2)O_(3)),alumoakaganeite(β-Fe_(1−x)Al_(x)O(OH,Cl)),and chromite(FeCr_(2)O_(4)).The efficiency of Fe extraction from the bauxite by HCl leaching was 82.5%at 100℃,HCl concentration of 10%,solid/liquid ratio of 1:10,and the process duration of 60 min,with aluminum loss from the bauxites below 4.5%of the total Al contents in the bauxite.Analysis of the kinetics of the iron leaching process proved diffusion to be the limiting stage of the process at 90−100℃.Bauxite residue after leaching presented traces of α-Fe_(1−x)Al_(x)OOH and β-Fe_(1−x)Al_(x)O(OH,Cl),and most of the iron content was in the FeCr_(2)O_(4).In bauxite residue after HCl leaching,in addition to iron oxide,the contents of chromium and calcium oxides significantly decreased.The iron chloride liquor after leaching contained the rare earth elements(REE)of 6.8 mg/L Sc,4.1 mg/L Ce and 2.3 mg/L Ga. 展开更多
关键词 BAUXITE acid leaching iron extraction KINETICS mössbauer spectroscopy
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Mechanism of the DL-alpha-aminoadipic acid inhibitory effect on form-deprived myopia in guinea pig 被引量:5
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作者 Jun-Feng Mao Shuang-Zhen Liu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2013年第1期19-22,共4页
AIM:To investigate the effect of intravitreal injection of DL-alpha-aminoadipic acid (DL-α-AAA) on ocular refractive state and retinal dopamine, transforming growth factor-β2 (TGFβ2 ), vasoactive intestinal polypep... AIM:To investigate the effect of intravitreal injection of DL-alpha-aminoadipic acid (DL-α-AAA) on ocular refractive state and retinal dopamine, transforming growth factor-β2 (TGFβ2 ), vasoactive intestinal polypeptide (VIP) in guinea pig form-deprived myopia. METHODS:Four-week-old pigmented guinea pigs were randomly assigned to 4 groups:normal control, deprivation, deprivation plus DL-α-AAA, deprivation plus saline. Form deprivation was induced with the self-made translucent eye shields, and lasted for 14 days. 8μg DL-α-AAA was injected into the vitreous chamber of deprived eyes. The corneal radius of curvature, refraction and axial length were measured. Retinal dopamine content was evaluated by the high-performance liquid chromatography with electrochemical detection, and TGFβ2 and VIP protein were detected by Western blotting. RESULTS:Fourteen days of eye occlusion caused the axial length to elongate and become myopic in the form-deprived eyes, with the decrease of retinal dopamine and the increase of TGFβ 2 and vasoactive intestinal polypeptide (VIP) protein. Intravitreal injection of DL-α-AAA could inhibit the myopic shift from (-3.65±1.06)D to (-1.48 ±0.63)D, P 【0.01 due to goggles occluding and cause the decrease of retinal TGFβ2 protein in the deprived eyes. However, intravitreal injection of DL-α-AAA had no significant effect on retinal dopamine and VIP protein in deprived eyes. Retinal TGFβ2 protein correlated highly with the ocular refraction (y =-3.34 + 0.31/x , F =74.75, P 【0.001) and axial length (y =8.39-0.02/ x , F =48.32, P 【0.001) in different treatment groups. ·CONCLUSION:Intravitreal injection of DL-α-AAA is effectively able to suppress the development of form deprivation myopia, which may be associated with retinalTGFβ2 protein in guinea pigs. 展开更多
关键词 DL-alpha-aminoadipic acid form-deprivation myopia TGFΒ2 müller cell retina
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Luminescent Properties of Bi-Rare Earth Complexes with m-methylbenzoic Acid and 1,10-phenanthroline 被引量:4
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作者 王淑萍 王瑞芬 刘翠格 《Journal of Rare Earths》 SCIE EI CAS CSCD 2002年第5期453-456,共4页
The bi rare earth complexes EuTb( m MBA) 6(phen) 2·2H 2O, TbY( m MBA) 6(phen) 2·2H 2O were synthesized by the reaction of RECl 3 with m methylbenzoic acid and 1,10 phenanthroline in eth... The bi rare earth complexes EuTb( m MBA) 6(phen) 2·2H 2O, TbY( m MBA) 6(phen) 2·2H 2O were synthesized by the reaction of RECl 3 with m methylbenzoic acid and 1,10 phenanthroline in ethanol solution, where m MBA=m methylbenzoate and phen=1,10 phenanthroline. The luminescence properties of the title complexes were studied in comparison with the corresponding complexes Eu 2( m MBA) 6(phen) 2·2H 2O and Tb 2( m MBA) 6(phen) 2·2H 2O respectively. The results indicate that the emission intensity from europium ion can be greatly enhanced by the terbium ion, while the emission from terbium ion was strongly quenched by europium ion in EuTb( m MBA) 6(phen) 2·2H 2O; the emission intensity from terbium ion can be greatly enhanced by yttrium ion in TbY( m MBA) 6(phen) 2·2H 2O. The mechanism about the results was discussed. 展开更多
关键词 rare earths luminescence property mixed rare earth complex m methylbenzoic acid 1 10 phenanthroline
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Role of bile acids in the regulation of the metabolic pathways 被引量:11
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作者 Hiroki Taoka Yoko Yokoyama +5 位作者 Kohkichi Morimoto Naho Kitamura Tatsuya Tanigaki Yoko Takashina Kazuo Tsubota Mitsuhiro Watanabe 《World Journal of Diabetes》 SCIE CAS 2016年第13期260-270,共11页
Recent studies have revealed that bile acids(BAs)are not only facilitators of dietary lipid absorption but also important signaling molecules exerting multiple physiological functions.Some major signaling pathways inv... Recent studies have revealed that bile acids(BAs)are not only facilitators of dietary lipid absorption but also important signaling molecules exerting multiple physiological functions.Some major signaling pathways involving the nuclear BAs receptor farnesoid X receptor and the G protein-coupled BAs receptor TGR5/M-BAR have been identified to be the targets of BAs.BAs regulate their own homeostasis via signaling pathways.BAs also affect diverse metabolic pathways including glucose metabolism,lipid metabolism and energy expenditure.This paper suggests the mechanism of controlling metabolism via BA signaling and demonstrates that BA signaling is an attractive therapeutic target of the metabolic syndrome. 展开更多
关键词 BILE acidS TGR5/m-BAR Farnesoid X receptor Glucose mETABOLISm Energy mETABOLISm Lipid mETABOLISm BARIATRIC surgery mICROBIOTA INCRETIN BILE acid binding resin
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A Study of Acidic Sites in H[M]-ZSM-5 Zeolites by XPS, IR and TPD
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作者 XTAO Feng-shou , XU Ru-ren and XU Yi-hua (Department of Chemistry, Jilin University, Changchun, 130023)WEI Quan (Center of Measurement and Analysis, Jilin University, Changchun, 130023) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1992年第4期337-342,共6页
The present paper covers an X-ray photoelectron spectroscopic (XPS) method proposed for identifying Bronsted and Lewis acidic sites in zeolites and estimating acidic strength of these sites. It was found that the adso... The present paper covers an X-ray photoelectron spectroscopic (XPS) method proposed for identifying Bronsted and Lewis acidic sites in zeolites and estimating acidic strength of these sites. It was found that the adsorption of pyridine on different acidic sites of H[M]-ZSM-5 zeolites exhibited three peaks: A (402.20-401.30 eV), B (400.95-400.40 eV) and C (399. 40-399. 10 eV). The peaks A and B are assigned to the N(?) level of pyridine adsorbed on Bronsted and Lewis acidic sites, and peak C is assigned to the N(?) level of pyridine adsorbed on a weak Lewis site and/or strongly physisorbed pyridine, respectively. The comparison of the ratio of the Bronsted and Lewis acidic sites determined from the relative intensities of the N(?), peaks with IR spectroscopic data shows that there is an inhomoge-neous distribution of Bronsted and Lewis acidic sites in H[M]-ZSM-5 zeolites. The N(?), binding energies of pyridine adsorbed on these zeolites directly reflect acidic strength, and these results are in good agreement with those observed in NH3-TPD experiments. 展开更多
关键词 acidity XPS H[m]-ZSm-5 zeolites Adsorption of pyridine IR and TPD
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Inhibition Effects of Salvianolic Acid M and Rosmarinic Acid in Salvia deserta Schang on Human Aldose Reductase
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作者 Qian HE Jie WU +1 位作者 Xinling WANG Jian YANG 《Asian Agricultural Research》 2019年第8期69-70,共2页
[Objectives]This study aimed to investigate the inhibition effects of two chemical constituents in Salvia deserta Schang on human aldose reductase( AR). [Methods]The isolated salvianolic acid M and rosmarinic acid wer... [Objectives]This study aimed to investigate the inhibition effects of two chemical constituents in Salvia deserta Schang on human aldose reductase( AR). [Methods]The isolated salvianolic acid M and rosmarinic acid were prepared into different concentrations of solutions for in vitro enzyme kinetics experiments. [Results]Salvianolic acid M and rosmarinic acid had the strongest inhibition effects at the concentration of 1 g/L. [Conclusions]Salvianolic acid M and rosmarinic acid have inhibition effects on human aldose reductase. The IC50 of salvianolic acid M is 0. 79 μg/mL,and that of rosmarinic acid is 1. 13 μg/mL. 展开更多
关键词 SALVIA deserta Schang ALDOSE REDUCTASE Salvianolic acid m Rosmarinic acid
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Effect of Indole Butyric Acid on the Transportation of Stored Calcium in Malus hupehensis Rhed. Seedling
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作者 LI Jia YANG Hong-qiang +1 位作者 YAN Tian-li SHU Huai-rui 《Agricultural Sciences in China》 CAS CSCD 2006年第11期834-838,共5页
Calcium (Ca) plays an important role in the metabolism of higher plants. Recently, research on Ca^2+ in plants has been focused especially at the cellular and molecular levels. Uptake, transport, and distribution a... Calcium (Ca) plays an important role in the metabolism of higher plants. Recently, research on Ca^2+ in plants has been focused especially at the cellular and molecular levels. Uptake, transport, and distribution are also very important for Ca to accomplish its function at the whole-plant level. In this experiment, one-year-old apple seedlings (M. hupehensis Rehd.) were investigated to determine the distribution of stored Ca, the different forms of Ca, and Ca^2+-ATPase activity after treatment with indole butyric acid (IBA). The results showed that the total Ca measured in mature leaves and Ca^2+- ATPase activity in tender leaves were higher compared with those in the control (CK). Calcium nitrate and calcium chloride (ALe-Ca) and calcium phosphate and calcium carbonate (HAC-Ca) decreased in both mature leaves and shoots, whereas water-soluble calcium (H2O-Ca), calcium pectate (NaCl-Ca), and calcium oxalate (HCl-Ca) increased. The percentage of active calcium, calcium pectate, and water-soluble calcium increased, whereas the percentage of calcium phosphate and calcium carbonate decreased. When treated with IBA, calcium fractions and percentage of the different forms of Ca was enhanced in 40 part per million (ppm) IBA compared with 20 ppm IBA and water. The results indicated that IBA increased the percentage of both active calcium (NaCl-Ca and H2O-Ca) in tender shoots and boosted the transportation of stored Ca in plants. IBA promoted Ca^2+-ATPase activity and Ca^2+ uptake in tender shoots of M. hupehensis. It can improve the total Ca contents and the relative percentage of Ca. 展开更多
关键词 indole butyric acid stored calcium m. hupehensis Rehd.
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Clinical application of combined detection of SARS-CoV-2-specific antibody and nucleic acid
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作者 Qing-Bin Me ng Jing-Jing Peng +8 位作者 Xin Wei Jia-Yao Yang Peng-Cheng Li Zi-Wei Qu Yong-Fen Xiong Guang-Jiang Wu Zhi-Min Hu Jian-Chun Yu Wen Su 《World Journal of Clinical Cases》 SCIE 2020年第19期4360-4369,共10页
BACKGROUND The global outbreak of human severe acute respiratory syndrome coronavirus(SARS-CoV)-2 infection represents an urgent need for readily available,accurate and rapid diagnostic tests.Nucleic acid testing of r... BACKGROUND The global outbreak of human severe acute respiratory syndrome coronavirus(SARS-CoV)-2 infection represents an urgent need for readily available,accurate and rapid diagnostic tests.Nucleic acid testing of respiratory tract specimens for SARS-CoV-2 is the current gold standard for diagnosis of coronavirus disease 2019(COVID-19).However,the diagnostic accuracy of reverse transcription polymerase chain reaction(RT-PCR)tests for detecting SARS-CoV-2 nucleic acid may be lower than optimal.The detection of SARS-CoV-2-specific antibodies should be used as a serological non-invasive tool for the diagnosis and management of SARS-CoV-2 infection.AIM To investigate the diagnostic value of SARS-CoV-2 IgM/IgG and nucleic acid detection in COVID-19.METHODS We retrospectively analyzed 652 suspected COVID-19 patients,and 206 non-COVID-19 patients in Wuhan Integrated TCM and Western Medicine Hospital.Data on SARS-CoV-2 nucleic acid tests and serum antibody tests were collected to investigate the diagnostic value of nucleic acid RT-PCR test kits and immunoglobulin(Ig)M/IgG antibody test kits.The j2 test was used to compare differences between categorical variables.A 95%confidence interval(CI)was provided by the Wilson score method.All analyses were performed with IBM SPSS Statistics version 22.0(IBM Corp.,Armonk,NY,United States).RESULTS Of the 652 suspected COVID-19 patients,237(36.3%)had positive nucleic acid tests,311(47.7%)were positive for IgM,and 592(90.8%)were positive for IgG.There was a significant difference in the positive detection rate between the IgM and IgG test groups(P<0.001).Using the RT-PCR results as a reference,the specificity,sensitivity,and accuracy of IgM/IgG combined tests for SARS-CoV-2 infection were 98.5%,95.8%,and 97.1%,respectively.Of the 415 suspected COVID-19 patients with negative nucleic acid test results,366 had positive IgM/IgG tests with a positive detection rate of 88.2%.CONCLUSION Our data indicate that serological IgM/IgG antibody combined test had high sensitivity and specificity for the diagnosis of SARS-CoV-2 infection,and can be used in combination with RT-PCR for the diagnosis of SARS-CoV-2 infection. 展开更多
关键词 SARS-CoV-2 COVID-19 Nucleic acid detection Immunoglobulin m Immunoglobulin G DIAGNOSIS
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Preparation and biological evaluation of ^(99)Tc^m-labelled fatty acids
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作者 LIANG Jixin HU Ji CHEN Baojun LUO Lianzhe LI Hongyu SHEN Langtao LUO Zhifu 《Nuclear Science and Techniques》 SCIE CAS CSCD 2007年第3期159-163,共5页
The aim of the present work was to develop radiolabelling fatty acids based on 99Tcm carbonyl chemistry for heart imaging. Undecanoic acids functionalised with iminodiacetatic acid and cysteine were radiolabelled with... The aim of the present work was to develop radiolabelling fatty acids based on 99Tcm carbonyl chemistry for heart imaging. Undecanoic acids functionalised with iminodiacetatic acid and cysteine were radiolabelled with [99Tcm (CO)3(H2O)3]+ intermediates, and their radiolabelling conditions were carefully studied. Biodistribution of 99Tcm (CO)3-CYST FAC11 and 99Tcm (CO)3-IDA FAC11 were observed in normal mice. The results showed that two 99Tcm-labelled compounds had similar profile in terms of high initial radioactivity uptake and rapid washout of radio- tracers in the heart. 99Tcm (CO)3-IDA FAC11 was mainly excreted via hepatobiliary system in contrast to 99Tcm (CO)3-CYST FAC11, which was excreted from urinary system. It may be in part attributed to the more lipophilicity of 99Tcm (CO)3-IDA FAC11 than 99Tcm (CO)3-CYST FAC11. 展开更多
关键词 脂肪酸 放射性同位素 ^99TC^m 医学应用
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A Fluorescent Cadmium-organic Framework Constructed by m-Thioacetatebenzoic Acid
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作者 詹才宏 王晓娟 +1 位作者 姜美香 冯云龙 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第12期1864-1868,共5页
Reactions of Cd(OAC)2·2H2O with m-thioacetatebenzoic acid(H2L) and 1,10-phenanthroline(phen) give rise to a metal-organic framework,[CdL(phen)]n(1).X-ray single-crystal diffraction reveals that 1 crysta... Reactions of Cd(OAC)2·2H2O with m-thioacetatebenzoic acid(H2L) and 1,10-phenanthroline(phen) give rise to a metal-organic framework,[CdL(phen)]n(1).X-ray single-crystal diffraction reveals that 1 crystallizes in the monoclinic system,space group C2/c,with a= 25.7099(5),b=10.3872(2),c=19.1820(4),β=131.114(1)°,V=3859.4(1)3,Mr=502.80,Z= 8,F(000)=2000,μ=1.271 mm-1,Dc=1.731 g·cm-3,the final R=0.0226 and wR=0.0559 for 3817 observed reflections(Ⅰ〉 2σ(Ⅰ)).1 displays a 1D double-strand chain structure with crab-like dinuclear subunits,and extends into a 3D network by π-π interactions and C-H···O hydrogen bonds.Photoluminescence studies reveal that it displays intense structure-related fluorescent emission bands(λex=342 nm) at 370.5 and 389 nm in the solid state at room temperature. 展开更多
关键词 hydrothermal synthesis m-thioacetatebenzoic acid metal-organic framework fluorescence
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