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Nissen fundoplication vs proton pump inhibitors for laryngopharyngeal reflux based on p H-monitoring and symptom-scale 被引量:15
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作者 Chao Zhang Zhi-Wei Hu +7 位作者 Chao Yan Qiong Wu Ji-Min Wu Xing Du Dian-Gang Liu Tao Luo Fei Li Zhong-Gao Wang 《World Journal of Gastroenterology》 SCIE CAS 2017年第19期3546-3555,共10页
AIM To compare the outcomes between laparoscopic Nissen fundoplication(LNF)and proton pump inhibitors(PPIs)therapy in patients with laryngopharyngeal reflux(LPR)and typeⅠhiatal hernia diagnosed by oropharyngeal p H-m... AIM To compare the outcomes between laparoscopic Nissen fundoplication(LNF)and proton pump inhibitors(PPIs)therapy in patients with laryngopharyngeal reflux(LPR)and typeⅠhiatal hernia diagnosed by oropharyngeal p H-monitoring and symptom-scale assessment.METHODS From February 2014 to January 2015,70 patients who were diagnosed with LPR and type I hiatal hernia and referred for symptomatic assessment,oropharyngeal p H-monitoring,manometry,and gastrointestinal endoscopy were enrolled in this study.All of the patients met the inclusion criteria.All of the patients underwent LNF or PPIs administration,and completed a2-year follow-up.Patients’baseline characteristics and primary outcome measures,including comprehensive and single symptoms of LPR,PPIs independence,and satisfaction,and postoperative complications were assessed.The outcomes of LNF and PPIs therapy were analyzed and compared. RESULTS There were 31 patients in the LNF group and 39patients in the PPI group.Fifty-three patients(25 in the LNF group and 28 in the PPI group)completed reviews and follow-up.Oropharyngeal p H-monitoring parameters were all abnormal with high acid exposure,a large amount of reflux,and a high Ryan score,associated reflux symptom index(RSI)score.There was a significant improvement in the RSI and LPR symptom scores after the 2-year follow-up in both groups(P<0.05),as well as typical symptoms of gastroesophageal reflux disease.Improvement in the RSI(P<0.005)and symptom scores of cough(P=0.032),mucus(P=0.011),and throat clearing(P=0.022)was significantly superior in the LNF group to that in the PPI group.After LNF and PPIs therapy,13 and 53 patients achieved independence from PPIs therapy(LNF:44.0%vs PPI:7.14%,P<0.001)during follow-up,respectively.Patients in the LNF group were more satisfied with their quality of life than those in the PPI group(LNF:62.49±28.68 vs PPI:44.36±32.77,P=0.004).Body mass index was significantly lower in the LNF group than in the PPI group(LNF:22.2±3.1kg/m^2 vs PPI:25.1±2.9 kg/m^2,P=0.001).CONCLUSION Diagnosis of LPR should be assessed with oropharyngeal p H-monitoring,manometry,and the symptom-scale.LNF achieves better improvement than PPIs for LPR with type I hiatal hernia. 展开更多
关键词 Laryngopharyngeal reflux hiatal hernia Laparoscopic Nissen fundoplication proton pump inhibitor p h-monitoring Gastroesophageal reflux disease
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Effect of Soil p H on the Growth,Photosynthesis and Mineral Element Content in Own-Rooted Saplings and Grafted Saplings of Blueberry 被引量:4
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作者 Chengxiang XU Yanping MA Feng GUO 《Asian Agricultural Research》 2017年第11期75-81,共7页
The adaptation of blueberry to higher soil p H is poor. To explore the effect and probable mechanism of the adaptation of grafted blueberry( Vaccinium spp.) saplings to the soil environment with higher p H value. We t... The adaptation of blueberry to higher soil p H is poor. To explore the effect and probable mechanism of the adaptation of grafted blueberry( Vaccinium spp.) saplings to the soil environment with higher p H value. We took three types of saplings,( i) own-rooted Wufanshu( V. bracteatum),an economical shrub belonging to the same genus and family with blueberry,also known as oriental blueberry,( ii) own-rooted‘Sharpblue',a southern highbush blueberry( V. corymbosum) cultivar,and( iii) grafted-bluebedrry as experimental materials,which were grown in quartz sand medium for 90 d,irrigated with nutrient solution of three levels of p H values,respectively,i. e. p H 4. 6,p H 5. 8 and p H7. 0. Results showed that root development,shoot growth and dry biomass accumulation of grafted blueberry were significantly better than those of own-rooted blueberry grown in higher p H medium; compared with own-rooted blueberry saplings,leaf chlorophyll content,chlorophyll a/b ratio,chlorophyll fluorescence chemical efficiency and photosynthetic efficiency of grafted blueberry saplings grown in higher p H medium were all significantly improved. Results also showed that mineral element content of leaves,especially Mg and Fe elemental content of grafted blueberry was significantly higher than that of own-rooted blueberry saplings grown in higher p H media. Grafting-propagation of blueberry saplings taking Wufanshu as rootstock significantly enhanced the adaptation of blueberry to soil environment with higher p H value. 展开更多
关键词 BLUEBERRY Wufanshu GRAFTING p h stress Adaptation
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Identifying the influence of urbanization on soil organic matter content and p H from soil magnetic characteristics 被引量:4
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作者 YANG Han XIONG Heigang +2 位作者 CHEN Xuegang WANG Yaqi ZHANG Fang 《Journal of Arid Land》 SCIE CSCD 2015年第6期820-830,共11页
Soil magnetic characteristics are correlated with soil p H and organic matter content. Analyzing soil magnetic characteristics, organic matter content and p H can indirectly evaluate soil pollution caused by human act... Soil magnetic characteristics are correlated with soil p H and organic matter content. Analyzing soil magnetic characteristics, organic matter content and p H can indirectly evaluate soil pollution caused by human activities. This study analyzed the soil magnetic characteristics, organic matter content and p H in surface soil samples from different land use types in Shihezi city, a newly and rapidly developing oasis city in Xinjiang of China. The aims of this study were to explore the possible relationships among the soil magnetic parameters and thereby improve the understanding of influence of urbanization on soil properties. Eighty surface soil samples at the depth of 0–10 cm were collected from 29 July to 4 August 2013. The results showed that the magnetic minerals in surface soil were dominated by ferromagnetic minerals. Spatially, the magnetic susceptibility(χLF), anhysteretic remanent magnetization susceptibility(χARM), saturation isothermal remanent magnetization(SIRM) and "soft" isothermal remanent magnetization(SOFT) were found to be most dominant in the new northern urban area B(N-B), followed by built-up areas(U), suburban agricultural land(F), and then the new northern urban area A(N-A). The values of χLF, χARM, SIRM and SOFT were higher in the areas with high intensities of human activities and around the main roads. Meanwhile, the property "hard" isothermal remanent magnetization(HIRM) followed the order of U〉N-B〉F〉N-A. Built-up areas had an average p H value of 7.93, which was much higher than that in the new northern urban areas as well as in suburban agricultural land, due to the increased urban pollutant emissions. The average value of soil organic matter content in the whole study area was 34.69 g/kg, and the values in the new northern urban areas were much higher than those in the suburban agricultural land and built-up areas. For suburban agricultural land, soil organic matter content was significantly negatively correlated with χLF, and had no correlation with other magnetic parameters, since the soil was frequently ploughed. In the new northern urban areas(N-A and N-B), there were significant positive correlations of soil organic matter contents with χARM, SIRM, SOFT and HIRM, because natural grasslands were not frequently turned over. For the built-up areas, soil organic matter contents were significantly positively correlated with χLF, χARM, SIRM and SOFT, but not significantly correlated with frequency-dependent susceptibility(χFD, expressed as a percentage) and HIRM, because the soil was not frequently turned over or influenced by human activities. The results showed that soil magnetic characteristics are related to the soil turnover time. 展开更多
关键词 environmental magnetism surface soil p h soil organic matter content
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Common eye drops and their implications for p H measurements in the management of chemical eye injuries
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作者 Lik Thai Lim Elliott Y.Ah-kee Cian E.Collins 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2014年第6期1067-1068,共2页
Dear Sir,Eye drops(single use)commonly used in clinics do have varying pH values.The use of such drops in the initial management of chemical eye injury may influence the accuracy of pH measurement of the eye,and subse... Dear Sir,Eye drops(single use)commonly used in clinics do have varying pH values.The use of such drops in the initial management of chemical eye injury may influence the accuracy of pH measurement of the eye,and subsequently influence its management.Chemical eye injury is an ophthalmic emergency,which may be caused by exposure to an acidic(pH【4)or an alkali(pH】10)solution to the eye.Rinsing the eye decreases the concentration of these solutions on ocular surface.The initial management would be copious irrigation with clean or sterile water or Ringer’s solution(pH 7.3-7.4)or its equivalent,of a 展开更多
关键词 ph Common eye drops and their implications for p h measurements in the management of chemical eye injuries
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Unreported complication of Bravo p H capsule dislodged into the pyriform sinus 被引量:1
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作者 Akash Kumar Elisabeth Kramer Sita Chokhavatia 《World Journal of Gastrointestinal Endoscopy》 CAS 2015年第5期573-574,共2页
We report an unexpected, previously unreported complication of Bravo p H capsule dislodgement. During Bravo p H testing of a 44-year-old man with gastroesophageal reflux disease, we were unable to endoscopically visua... We report an unexpected, previously unreported complication of Bravo p H capsule dislodgement. During Bravo p H testing of a 44-year-old man with gastroesophageal reflux disease, we were unable to endoscopically visualize the capsule attached to the esophageal wall after deployment. After multiple attempts to detect the capsule, it was visualized in the left pyriform sinus. As there was significant risk for pulmonary dislodgement, ENT and pulmonary physicians were immediately consulted to review options for safe removal. Ultimately, ENT successfully retrieved the capsule with a foreign body removal forceps. The Bravo p H test is generally a well-tolerated diagnostic tool used to confirm the presence of abnormal esophageal acid reflux. While few complications have been reported, technical difficulties can occur, including poor data reception, misplacement, and early dislodgement. Rarely, more serious complications can occur, ranging from esophageal wall trauma to capsule aspiration. Gastroenterologists performing this procedure should be aware of the low, but nontrivial, risk of complications. 展开更多
关键词 GASTROESOphAGEAL REFLUX disease Esophagealph monitoring BRAVO CApSULE Dislodgement ESOphAGOGASTRODUODENOSCOpY
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Pre-lung transplant measures of reflux on impedance are superior to p H testing alone in predicting early allograft injury
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作者 Wai-Kit Lo Robert Burakoff +2 位作者 Hilary J Goldberg Natan Feldman Walter W Chan 《World Journal of Gastroenterology》 SCIE CAS 2015年第30期9111-9117,共7页
AIM:To evaluate pre-lung transplant acid reflux on p H-testing vs corresponding bolus reflux on multichannel intraluminal impedance(MII) to predict early allograft injury.METHODS:This was a retrospective cohort study ... AIM:To evaluate pre-lung transplant acid reflux on p H-testing vs corresponding bolus reflux on multichannel intraluminal impedance(MII) to predict early allograft injury.METHODS:This was a retrospective cohort study of lung transplant recipients who underwent pretransplant combined MII-p H-testing at a tertiary care center from January 2007 to November 2012. Patients with pre-transplant fundoplication were excluded. Time-to-event analysis was performed using a Cox proportional hazards model to assess associations between measures of reflux on MII-p H testing and early allograft injury. Area under the receiver operating characteristic(ROC) curve(c-statistic) of the Cox model was calculated to assess the predictive value of each reflux parameter for early allograft injury. Six p H-testing parameters and their corresponding MIImeasures were specified a priori. The p H parameters were upright,recumbent,and overall acid reflux exposure; elevated acid reflux exposure; total acid reflux episodes; and acid clearance time. The corresponding MII measures were upright,recumbent,and overall bolus reflux exposure; elevated bolus reflux exposure; total bolus reflux episodes; and bolus clearance time.RESULTS:Thirty-two subjects(47% men,mean age:55 years old) met the inclusion criteria of the study. Idiopathic pulmonary fibrosis(46.9%) repres e n t e d t h e m o s t c o m m o n p u l m o n a r y d i a g n o s i s leading to transplantation. Baseline demographics,pre-transplant cardiopulmonary function,number of lungs transplanted(unilateral vs bilateral),and posttransplant proton pump inhibitor use were similar between reflux severity groups. The area under the ROC curve,or c-statistic,of each acid reflux parameter on pre-transplant p H-testing was lower than its bolus reflux counterpart on MII in the prediction of early allograft injury. In addition,the development of early allograft injury was significantly associated with three pre-transplant MII measures of bolus reflux:overall reflux exposure(HR = 1.18,95%CI:1.01-1.36,P = 0.03),recumbent reflux exposure(HR = 1.25,95%CI:1.04-1.50,P = 0.01) and bolus clearance(HR = 1.09,95%CI:1.01-1.17,P = 0.02),but not with any p Htesting parameter measuring acid reflux alone.CONCLUSION:Pre-transplant MII measures of bolus reflux perform better than their p H-testing counterparts in predicting early allograft injury post-lung transplantation. 展开更多
关键词 Gastroesophageal REFLUX Lung transplant Multichannel INTRALUMINAL IMpEDANCE ph-monitoring ALLOGRAFT INJURY
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钙法脱硫中浆液pH和密度控制技术应用研究
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作者 王存 夏顺堂 《华东纸业》 2024年第8期60-62,共3页
造纸行业是我国的重要工业部门之一,但其生产过程中产生的大量废气废水,特别是二氧化硫(SO2)等酸性气体的排放,对环境造成了严重污染。近年来,随着环保要求的日益严格,如何有效控制和减少二氧化硫的排放,成为造纸企业亟待解决的问题。... 造纸行业是我国的重要工业部门之一,但其生产过程中产生的大量废气废水,特别是二氧化硫(SO2)等酸性气体的排放,对环境造成了严重污染。近年来,随着环保要求的日益严格,如何有效控制和减少二氧化硫的排放,成为造纸企业亟待解决的问题。钙法脱硫技术作为一种成熟的脱硫方法,因其成本低廉、工艺简单、适用范围广等优势,已在众多行业得到广泛应用,然而,钙法脱硫技术在应用过程中,浆液的PH值和密度对脱硫效果有着显著影响,这也是目前研究的热点和难点。文章通过探讨钙法脱硫技术在造纸行业中的应用,研究浆液pH值和密度控制对脱硫效率的影响,找出最优的PH值和密度控制策略,从而提高脱硫效率,降低运行成本实现环保达标。 展开更多
关键词 钙法脱硫 浆液p h 密度控制技术 应用研究
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基于项目式学习的植物色素自制pH试纸活动设计实践探索
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作者 李芸 杨丽华 +3 位作者 陈凌凌 严德振 胡琼 黄国保 《玉林师范学院学报》 2024年第3期110-123,共14页
项目式学习是一种有助于促进育人方式转型、发展核心素养和落实新课改理念的学习方式.本文在理论研究的基础上,凝练了基于项目式学习的化学实验探究活动设计流程,根据设计流程将“植物色素自制pH试纸”学习项目拆分为“收集当下季节的... 项目式学习是一种有助于促进育人方式转型、发展核心素养和落实新课改理念的学习方式.本文在理论研究的基础上,凝练了基于项目式学习的化学实验探究活动设计流程,根据设计流程将“植物色素自制pH试纸”学习项目拆分为“收集当下季节的植物”“提取植物色素”“测试植物色素显色范围”和“制作植物色素pH试纸”四个子任务.学生通过分析问题和解决问题完成项目任务,最终获得项目产品——植物色素pH试纸,并在项目式学习的过程中,深刻体会了项目式学习的活动设计流程,培养了科学探究思维,发展了问题解决能力,理解了学科(或跨学科)实践活动的育人理念,为师范生今后开展基于项目式学习的化学实验探究活动做了很好的示范. 展开更多
关键词 项目式学习 化学实验探究活动 植物色素 p h试纸
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高温高压下P110H套管钢的Cl^(-)腐蚀行为研究 被引量:2
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作者 朱德学 谭伟 《广东化工》 CAS 2024年第5期83-86,118,共5页
套管的服役环境日益复杂,关于热采井套管在高温高压Cl^(-)溶液中的腐蚀行为需要进一步探索。为此,使用高温高压真空反应釜进行腐蚀模拟实验,并通过腐蚀失重法、扫描电镜、X射线衍射等分析技术,对P110H钢在高温高压Cl^(-)溶液中的腐蚀行... 套管的服役环境日益复杂,关于热采井套管在高温高压Cl^(-)溶液中的腐蚀行为需要进一步探索。为此,使用高温高压真空反应釜进行腐蚀模拟实验,并通过腐蚀失重法、扫描电镜、X射线衍射等分析技术,对P110H钢在高温高压Cl^(-)溶液中的腐蚀行为进行了研究。结果表明:高温高压Cl^(-)环境下,P110钢的腐蚀主要为均匀腐蚀,5 MPa时,腐蚀速率随着温度升高先降低后增高,在10 MPa时,腐蚀速率在250℃达到最高;在相同温度时,随着压力的增大,P110H钢在Cl^(-)溶液中的腐蚀越严重。 展开更多
关键词 p110h Cl^(-)溶液 高温高压 腐蚀
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NQO1 Mediates Lenvatinib Resistance by Regulating ROS-induced Apoptosis in Hepatocellular Carcinoma
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作者 Wei XUE Ting WANG +3 位作者 Wen-jing TIAN Si-qi PANG Hua-feng ZHANG Wei-dong JIA 《Current Medical Science》 SCIE CAS 2024年第1期168-179,共12页
Objective Hepatocellular carcinoma(HCC)is the third leading cause of cancer-associated death worldwide.As a first-line drug for advanced HCC treatment,lenvatinib faces a significant hurdle due to the development of bo... Objective Hepatocellular carcinoma(HCC)is the third leading cause of cancer-associated death worldwide.As a first-line drug for advanced HCC treatment,lenvatinib faces a significant hurdle due to the development of both intrinsic and acquired resistance among patients,and the underlying mechanism remains largely unknown.The present study aims to identify the pivotal gene responsible for lenvatinib resistance in HCC,explore the potential molecular mechanism,and propose combinatorial therapeutic targets for HCC management.Methods Cell viability and colony formation assays were conducted to evaluate the sensitivity of cells to lenvatinib and dicoumarol.RNA-Seq was used to determine the differences in transcriptome between parental cells and lenvatinib-resistant(LR)cells.The upregulated genes were analyzed by GO and KEGG analyses.Then,qPCR and Western blotting were employed to determine the relative gene expression levels.Afterwards,the intracellular reactive oxygen species(ROS)and apoptosis were detected by flow cytometry.Results PLC-LR and Hep3B-LR were established.There was a total of 116 significantly upregulated genes common to both LR cell lines.The GO and KEGG analyses indicated that these genes were involved in oxidoreductase and dehydrogenase activities,and reactive oxygen species pathways.Notably,NAD(P)H:quinone oxidoreductase 1(NQO1)was highly expressed in LR cells,and was involved in the lenvatinib resistance.The high expression of NQO1 decreased the production of ROS induced by lenvatinib,and subsequently suppressed the apoptosis.The combination of lenvatinib and NQO1 inhibitor,dicoumarol,reversed the resistance of LR cells.Conclusion The high NQO1 expression in HCC cells impedes the lenvatinib-induced apoptosis by regulating the ROS levels,thereby promoting lenvatinib resistance in HCC cells. 展开更多
关键词 hepatocellular carcinoma lenvatinib resistance NAD(p)h quinone oxidoreductase 1 reactive oxygen species apoptosis DICOUMAROL
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年龄对眼周NAD(P)H水平影响及一款眼霜抗皱功效评价
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作者 张小铿 施红 +3 位作者 刘玉 顾晶 许陶敏 范莹 《广东化工》 CAS 2024年第18期183-186,共4页
通过招募一批不同年龄段受试者,使用皮肤无创仪器检测方法分析眼周NAD(P)H水平与年龄、肤色和弹性参数R2之间的相关性。另招募一批受试者,使用一款眼霜评估眼部抗皱效果。研究结果表明:随着年龄增长,眼周颗粒层细胞NAD(P)H水平降低、鱼... 通过招募一批不同年龄段受试者,使用皮肤无创仪器检测方法分析眼周NAD(P)H水平与年龄、肤色和弹性参数R2之间的相关性。另招募一批受试者,使用一款眼霜评估眼部抗皱效果。研究结果表明:随着年龄增长,眼周颗粒层细胞NAD(P)H水平降低、鱼尾纹等级增大,皮肤弹性R2值减小,肤色加深,皮肤ITA°值减小。年龄、肤色、弹性与NAD(P)H水平之间存在相关性。15名受试者使用眼霜28天后,与使用前相比眼周NAD(P)H水平增加,皮肤弹性R2值增加,鱼尾纹评级下降,胶原纤维谐波强度增加。该产品具有一定的抗皱效果。 展开更多
关键词 衰老 皮肤 双光子显微镜 NAD(p)h 胶原纤维
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Novel two-step process to improve efficiency of bio-oxidation of Axi high-sulfur refractory gold concentrates 被引量:2
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作者 刘新星 王国华 +4 位作者 霍强 谢建平 李寿朋 武海艳 郭玉洁 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第12期4119-4125,共7页
In order to improve the bio-oxidation efficiency of Axi refractory gold concentrate, a two-step process including a high temperature chemical oxidation and a subsequent bio-oxidation, combined with p H control during ... In order to improve the bio-oxidation efficiency of Axi refractory gold concentrate, a two-step process including a high temperature chemical oxidation and a subsequent bio-oxidation, combined with p H control during the bio-oxidation step was used. The results revealed that the optimum mode was to maintain solution p H at 1.0-1.2 during the biological oxidation stage. Under this condition, the activity of mixed culture could be sustained and the formation of jarosite could be diminished, thus the oxidation efficiency was improved. The oxidation levels of iron and sulfur were improved by 12.50% and 15.49%, and the gold recovery was increased by 21.02%. Therefore, the two-step process combined with p H control is an effective method for oxidizing the biohydrometallurgical process of Axi gold concentrate, and it will have a broad prospect of application in dealing with complex refractory gold concentrate. 展开更多
关键词 gold concentrate BIO-OXIDATION p h control two-step oxidation
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原始蒙古语p、h辅音研究
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作者 金刚 《内蒙古社会科学(蒙文版)》 2024年第3期77-92,共16页
原始蒙古语语音系统中即存在P、h两个辅音,这两个辅音均保留于西支蒙古语族语言固有词词首。因为p辅音与蒙古语b辅音相对应,所以p辅音并非像G.J.兰司铁所提出的那样,发生了p>f>h>0的演变,而是发生了p>b的演变。h辅音虽然在... 原始蒙古语语音系统中即存在P、h两个辅音,这两个辅音均保留于西支蒙古语族语言固有词词首。因为p辅音与蒙古语b辅音相对应,所以p辅音并非像G.J.兰司铁所提出的那样,发生了p>f>h>0的演变,而是发生了p>b的演变。h辅音虽然在中古后期完全消失于蒙古语,但是在其它蒙古语族语言中都适当地保留了下来,并且在某些环境中还变成了别的辅音。大致在圆唇元音之前演变为f、p,在i元音之前演变为■等。也有在个别语言中演变为x、在个别语言中部分演变为x的现象。所以,就兰司铁所提出的p>f>h的定律而言,在原始蒙古语固有词的范围,无论其具有怎样的依据,均应视之为h>f>p之误。 展开更多
关键词 原始蒙古语 蒙古语族语言 固有ph辅音
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RP-HPLC法测定不同产地及采收期的穿心莲中穿心莲内酯、新穿心莲内酯的含量 被引量:36
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作者 陈敏武 徐德然 +2 位作者 王峥涛 徐珞珊 徐国钧 《中国药科大学学报》 CAS CSCD 北大核心 1999年第4期291-294,共4页
采用反相高效液相色谱法测定穿心莲中穿心莲内酯、新穿心莲内酯的含量。色谱柱为 Merck Lichroma R P C18 柱,流动相为乙腈水(35∶65) ,检测波长为225 nm ,流速为1 mlmin ,柱温40 ... 采用反相高效液相色谱法测定穿心莲中穿心莲内酯、新穿心莲内酯的含量。色谱柱为 Merck Lichroma R P C18 柱,流动相为乙腈水(35∶65) ,检测波长为225 nm ,流速为1 mlmin ,柱温40 ℃,穿心莲内酯和新穿心莲内酯的加样回收率分别为102 .62 % 、98 .6 % , R S D 分别为0 .48 % 、0 .47 % ,上述两成分在广东阳春和安徽临泉所产的穿心莲中含量较高,最佳采收期为开花盛期。 展开更多
关键词 穿心莲内酯 新穿心莲内酯 穿心莲 高效液相色谱
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土壤调理剂对红壤pH值及空心菜产量和品质的影响 被引量:40
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作者 李育鹏 胡海燕 +3 位作者 李兆君 孔庆波 戴春山 张永清 《中国土壤与肥料》 CAS CSCD 北大核心 2014年第6期21-26,共6页
土壤酸化是制约土壤高产稳产的重要因素,严重影响了我国农业的可持续发展。通过大田试验研究了以碳酸钙为主要原料生产的土壤调理剂对酸性土壤p H值、硅铝率及空心菜产量和品质的影响。结果表明,土壤调理剂可以增加土壤p H值和硅铝率,... 土壤酸化是制约土壤高产稳产的重要因素,严重影响了我国农业的可持续发展。通过大田试验研究了以碳酸钙为主要原料生产的土壤调理剂对酸性土壤p H值、硅铝率及空心菜产量和品质的影响。结果表明,土壤调理剂可以增加土壤p H值和硅铝率,提高空心菜的产量,改善空心菜的品质;与对照相比,土壤调理剂用量为600-1 800 kg/hm^2时,可使土壤p H值增加3.60%-21.65%,空心菜产量增加5.81%-44.45%,维生素C含量增加2.48%-23.97%,可溶性糖含量增加4.18%-26.48%;土壤调理剂对空心菜硝酸盐含量没有显著影响。研究发现,土壤调理剂用量为1 500 kg/hm^2时较为经济合理,表面撒施后旋耕是非常合理且有效的施用方法。 展开更多
关键词 土壤调理剂 p h 硅铝率 蔬菜 产量 品质
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不同pH和离子强度条件下青鱼(Mylopharyngodon piceus)肌浆蛋白IgG/IgE结合能力的变化 被引量:4
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作者 朱一丹 谢国锦 +6 位作者 高岭 杨方 高沛 余达威 姜启兴 许艳顺 夏文水 《食品与发酵工业》 CAS CSCD 北大核心 2020年第14期34-39,共6页
该文以青鱼为研究对象,研究肌浆蛋白在不同p H和离子强度条件下,Ig G/Ig E结合能力及结构的变化。通过间接酶联免疫吸附测定(indirect-enzyme linked immunosorbent assay,间接ELISA)、十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(sodium dodecy... 该文以青鱼为研究对象,研究肌浆蛋白在不同p H和离子强度条件下,Ig G/Ig E结合能力及结构的变化。通过间接酶联免疫吸附测定(indirect-enzyme linked immunosorbent assay,间接ELISA)、十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(sodium dodecylsulphate polyacrylamide gel electrophoresis,SDS-PAGE)和免疫印迹试验测定肌浆蛋白Ig G/Ig E结合能力的变化,并结合二级结构变化、表面疏水性变化和内源荧光值变化所反映的蛋白结构改变来分析其变化机理。结果表明,p H从4. 0升高到7. 0会小幅度降低肌浆蛋白Ig G/Ig E结合能力,二级结构中α-螺旋增加而不规则卷曲减少,表面疏水性大幅减小且色氨酸疏水基向极性环境暴露。离子强度从0增加到1. 0则不会对Ig G/Ig E结合能力产生显著影响。由此可知,肌浆蛋白Ig G/Ig E结合能力变化与其构象表位有关,初步判断主要由二级结构的改变引起,但仍需要进一步研究。 展开更多
关键词 p h 离子强度 Ig G/Ig E结合能力 青鱼 蛋白结构
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烟酰型辅酶NAD(P)^+和NAD(P)H再生的研究进展 被引量:20
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作者 吕陈秋 姜忠义 王姣 《有机化学》 SCIE CAS CSCD 北大核心 2004年第11期1366-1379,共14页
大部分氧化还原酶的催化反应需要烟酰型辅酶NAD(P) + 和NAD(P)H作为氧化剂或还原剂参与 ,由于氧化还原酶应用广泛而辅酶价格昂贵 ,使得辅酶再生逐渐成为研究热点 .综述了近年来NAD(P) + 和NAD(P)H酶法再生、电化学法及光化学法再生的研... 大部分氧化还原酶的催化反应需要烟酰型辅酶NAD(P) + 和NAD(P)H作为氧化剂或还原剂参与 ,由于氧化还原酶应用广泛而辅酶价格昂贵 ,使得辅酶再生逐渐成为研究热点 .综述了近年来NAD(P) + 和NAD(P)H酶法再生、电化学法及光化学法再生的研究进展 。 展开更多
关键词 烟酰型辅酶 NAD(p)^%pLUS% NAD(p)h 再生方法 氧化还原酶 酶法 电化学法 光化学法
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甘蔗NAD(P)H脱氢酶复合体O亚基基因克隆及其与甘蔗花叶病毒VPg互作 被引量:6
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作者 翟玉山 赵贺 +8 位作者 张海 邓宇晴 程光远 杨宗桃 王彤 彭磊 徐倩 董萌 徐景升 《作物学报》 CAS CSCD 北大核心 2019年第10期1478-1487,共10页
NAD(P)H脱氢酶(NDH)复合体介导循环电子传递,对于维持叶绿体高效的光合作用具有重要作用。甘蔗(Saccharum spp. hybrid)中NDH复合体应答及参与甘蔗花叶病毒(Sugarcane mosaic virus,SCMV)的侵染尚未见报道。本研究克隆了甘蔗NDH复合体的... NAD(P)H脱氢酶(NDH)复合体介导循环电子传递,对于维持叶绿体高效的光合作用具有重要作用。甘蔗(Saccharum spp. hybrid)中NDH复合体应答及参与甘蔗花叶病毒(Sugarcane mosaic virus,SCMV)的侵染尚未见报道。本研究克隆了甘蔗NDH复合体的O亚基,命名为ScNdhO,其开放读码框(open reading frame,ORF)长度为471 bp,编码长度为156 aa的蛋白。生物信息学分析表明,ScNdhO为稳定的亲水性蛋白,不存在信号肽,无跨膜结构域;蛋白二级结构元件多为无规则卷曲,具有典型的NDH复合体O亚基结构域;系统进化树分析表明,该蛋白属于NDH复合体O亚基蛋白家族。实时荧光定量 PCR分析发现,ScNdhO基因的表达具有明显的组织特异性,在成熟甘蔗叶片中的表达量最高,在茎中的表达量最低,在根中几乎不表达;ScNdhO基因在SCMV侵染早期上调表达,后期下调表达。亚细胞定位分析表明,ScNdhO定位于叶绿体。酵母双杂交(yeast two hybrid,Y2H)和双分子荧光互补(bimolecular fluorescence complementation,BiFC)实验表明,ScNdhO与SCMV-VPg互作。推测ScNdhO被SCMV选择性利用,可能参与SCMV基因组复制及花叶病症状的产生。 展开更多
关键词 甘蔗 SCMV 叶绿体 NAD(p)h脱氢酶复合体 O亚基
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pH依赖型黄芩苷纳米晶体结肠靶向微丸的制备及体外释药研究 被引量:13
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作者 程玲 郑娟 +6 位作者 沈刚 邱玲 李娟娟 张利红 武娜 韩晋 袁海龙 《中成药》 CAS CSCD 北大核心 2016年第2期298-303,共6页
目的制备pH依赖型黄芩苷纳米晶体结肠靶向微丸,并对影响其体外释药行为的包衣处方进行优化。方法采用探头超声联合高压均质技术制备黄芩苷纳米混悬剂,用流化床干燥法固化成纳米晶体微丸,并考察其再分散后的粒径、Zeta电位和多分散指数... 目的制备pH依赖型黄芩苷纳米晶体结肠靶向微丸,并对影响其体外释药行为的包衣处方进行优化。方法采用探头超声联合高压均质技术制备黄芩苷纳米混悬剂,用流化床干燥法固化成纳米晶体微丸,并考察其再分散后的粒径、Zeta电位和多分散指数。然后,将上述纳米晶体微丸进行流化床包衣,以微丸体外释放度为评价指标,对包衣处方进行优化。结果黄芩苷纳米晶体微丸再分散后,平均粒径为(281.90±10.56)nm,多分散指数(PI)为(0.195 1±0.043 2),Zeta电位为(-31.7±2.1)m V。最优包衣处方为以Eudragit S100为包衣材料,8%的柠檬酸三乙酯(TEC)为增塑剂,50%的滑石粉为抗黏剂,包衣增重量为15%。所制得的黄芩苷纳米晶体结肠靶向微丸在人工胃液2 h、小肠液4 h中的累积释药率小于13%,而在人工结肠液4 h中达93%。结论该制剂具有良好的结肠靶向释药性能。 展开更多
关键词 黄芩苷 纳米晶体 ph依赖 结肠靶向 体外释放
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卷烟主流烟气pH和粒相物pH的测定及与感官质量的关系 被引量:13
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作者 李青青 杨靖 +3 位作者 李文伟 赵海娟 王建民 程传玲 《烟草科技》 EI CAS CSCD 北大核心 2015年第10期62-66,共5页
为比较卷烟主流烟气pH及主流烟气粒相物pH与卷烟感官质量间的相关程度,检测了20个卷烟感官标准样品的两种pH以及烟丝烟碱、总糖、还原糖、总氮、钾、氯等常规化学成分的质量分数;根据20个样品的标准评吸得分,采用简单相关分析、逐步回... 为比较卷烟主流烟气pH及主流烟气粒相物pH与卷烟感官质量间的相关程度,检测了20个卷烟感官标准样品的两种pH以及烟丝烟碱、总糖、还原糖、总氮、钾、氯等常规化学成分的质量分数;根据20个样品的标准评吸得分,采用简单相关分析、逐步回归分析等方法研究了两种pH以及常规化学成分与感官质量间的关系。结果表明:1主流烟气pH与卷烟感官质量的相关性大于主流烟气粒相物pH,且大于除还原糖外的其他常规化学成分。220个卷烟感官标准样品的主流烟气pH在5.615~6.055之间变化,且表现出随感官质量得分升高而增大的变化规律。 展开更多
关键词 主流烟气 粒相物 ph 常规化学成分 感官质量
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