期刊文献+
共找到206,348篇文章
< 1 2 250 >
每页显示 20 50 100
PAM-PAA microgel inverse opal photonic crystal and pH response 被引量:1
1
作者 Yong Qiang He Xiao Dong Wang +3 位作者 Jian Ying Wang Yan Feng Yong Qiang Zhao Xiu Dong You 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第11期1395-1398,共4页
胶体的水晶模板或蛋白石与一包装结束以脸为中心立方(fcc ) 格子被准备从单音由垂直沉积驱散聚苯乙烯(PS ) 范围。为单体先锋的渗入的提供的空空格压克力填写了的模板从随后的 copolymerization 每硫酸盐,以及微胶化吃了酸,压克力酰... 胶体的水晶模板或蛋白石与一包装结束以脸为中心立方(fcc ) 格子被准备从单音由垂直沉积驱散聚苯乙烯(PS ) 范围。为单体先锋的渗入的提供的空空格压克力填写了的模板从随后的 copolymerization 每硫酸盐,以及微胶化吃了酸,压克力酰胺和铵。样品为完全移开 PS 范围形成 PAM 反的蛋白石水疗院胶化(IOHPAM ) 或 PAM/PAA 反的蛋白石水疗院胶化(IOHPAM/PAA ) 沉浸于 dimethylbenzene photonic 晶体。PS 范围坐飞机被代替范围,它通过窗户互连对方。对为 IOHPAM 和 IOHPAM/PAA 电影有二座山峰的 pH 表演的回答的学习,而是 IOHPAM/PAA 达到顶点到更高的 pH 的移动,和山峰与 AA 内容是独立的。 展开更多
关键词 光子学 ph 化学反应 反运算
下载PDF
mtDNA-triggered pH response signal-amplified fluorescent probe for multiple cell discrimination
2
作者 Tianping Xia Yanxian Hou +4 位作者 Zhuoran Xia Gengwen Chen Peichen Tang Jiangli Fan Xiaojun Peng 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第3期363-368,共6页
Developing fluorescence probes with multiple responses has vital significance but remains challenging.Herein,for the first time,we present a mitochondrial DNA(mtDNA)-triggered pH response signalamplified fluorescent p... Developing fluorescence probes with multiple responses has vital significance but remains challenging.Herein,for the first time,we present a mitochondrial DNA(mtDNA)-triggered pH response signalamplified fluorescent probe(QCY-DBT)for multiple cell detection.The probe exhibited a large stokes shift(229 nm),excellent DNA selectivity over RNA,and ultrasensitivity of detection limit(DL;74.0 ng/mL).Thus,QCY-DBT was successfully applied to analyze multiple human peripheral blood cells and visualize mtDNA in healthy and apoptotic cells.In the tumor acidic environment(pH 6.0–7.0),the absorbance of QCY-DBT at 436 nm increased,and the fluorescence signal(665 nm)was amplified by mtDNA,which enabled the direct observation of tumor cells.Our study provides help in designing smart probes with multiple responses for efficient abnormal cell detection. 展开更多
关键词 Fluorescence probe Mitochondrial DNA ph response Peripheral blood cells Multiple cell detection
原文传递
The physiological role of the unfolded protein response in the nervous system
3
作者 Shuangchan Wu Wensheng Lin 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第11期2411-2420,共10页
The unfolded protein response(UPR)is a cellular stress response pathway activated when the endoplasmic reticulum,a crucial organelle for protein folding and modification,encounters an accumulation of unfolded or misfo... The unfolded protein response(UPR)is a cellular stress response pathway activated when the endoplasmic reticulum,a crucial organelle for protein folding and modification,encounters an accumulation of unfolded or misfolded proteins.The UPR aims to restore endoplasmic reticulum homeostasis by enhancing protein folding capacity,reducing protein biosynthesis,and promoting protein degradation.It also plays a pivotal role in coordinating signaling cascades to determine cell fate and function in response to endoplasmic reticulum stress.Recent research has highlighted the significance of the UPR not only in maintaining endoplasmic reticulum homeostasis but also in influencing various physiological processes in the nervous system.Here,we provide an overview of recent findings that underscore the UPR’s involvement in preserving the function and viability of neuronal and myelinating cells under physiological conditions,and highlight the critical role of the UPR in brain development,memory storage,retinal cone development,myelination,and maintenance of myelin thickness. 展开更多
关键词 MYELIN NEURON OLIGODENDROCYTE Schwann cell unfolded protein response
下载PDF
Prediction of treatment response to antipsychotic drugs for precision medicine approach to schizophrenia:randomized trials and multiomics analysis
4
作者 Liang-Kun Guo Yi Su +24 位作者 Yu-Ya-Nan Zhang Hao Yu Zhe Lu Wen-Qiang Li Yong-Feng Yang Xiao Xiao Hao Yan Tian-Lan Lu Jun Li Yun-Dan Liao Zhe-Wei Kang Li-Fang Wang Yue Li Ming Li Bing Liu Hai-Liang Huang Lu-Xian Lv Yin Yao Yun-Long Tan Gerome Breen Ian Everall Hong-Xing Wang Zhuo Huang Dai Zhang Wei-Hua Yue 《Military Medical Research》 SCIE CAS CSCD 2024年第1期19-33,共15页
Background:Choosing the appropriate antipsychotic drug(APD)treatment for patients with schizophrenia(SCZ)can be challenging,as the treatment response to APD is highly variable and difficult to predict due to the lack ... Background:Choosing the appropriate antipsychotic drug(APD)treatment for patients with schizophrenia(SCZ)can be challenging,as the treatment response to APD is highly variable and difficult to predict due to the lack of effective biomarkers.Previous studies have indicated the association between treatment response and genetic and epigenetic factors,but no effective biomarkers have been identified.Hence,further research is imperative to enhance precision medicine in SCZ treatment.Methods:Participants with SCZ were recruited from two randomized trials.The discovery cohort was recruited from the CAPOC trial(n=2307)involved 6 weeks of treatment and equally randomized the participants to the Olanzapine,Risperidone,Quetiapine,Aripiprazole,Ziprasidone,and Haloperidol/Perphenazine(subsequently equally assigned to one or the other)groups.The external validation cohort was recruited from the CAPEC trial(n=1379),which involved 8 weeks of treatment and equally randomized the participants to the Olanzapine,Risperidone,and Aripiprazole groups.Additionally,healthy controls(n=275)from the local community were utilized as a genetic/epigenetic reference.The genetic and epigenetic(DNA methylation)risks of SCZ were assessed using the polygenic risk score(PRS)and polymethylation score,respectively.The study also examined the genetic-epigenetic interactions with treatment response through differential methylation analysis,methylation quantitative trait loci,colocalization,and promoteranchored chromatin interaction.Machine learning was used to develop a prediction model for treatment response,which was evaluated for accuracy and clinical benefit using the area under curve(AUC)for classification,R^(2) for regression,and decision curve analysis.Results:Six risk genes for SCZ(LINC01795,DDHD2,SBNO1,KCNG2,SEMA7A,and RUFY1)involved in cortical morphology were identified as having a genetic-epigenetic interaction associated with treatment response.The developed and externally validated prediction model,which incorporated clinical information,PRS,genetic risk score(GRS),and proxy methylation level(proxyDNAm),demonstrated positive benefits for a wide range of patients receiving different APDs,regardless of sex[discovery cohort:AUC=0.874(95%CI 0.867-0.881),R^(2)=0.478;external validation cohort:AUC=0.851(95%CI 0.841-0.861),R^(2)=0.507].Conclusions:This study presents a promising precision medicine approach to evaluate treatment response,which has the potential to aid clinicians in making informed decisions about APD treatment for patients with SCZ.Trial registration Chinese Clinical Trial Registry(https://www.chictr.org.cn/),18 Aug 2009 retrospectively registered:CAPOC-ChiCTR-RNC-09000521(https://www.chictr.org.cn/showproj.aspx?proj=9014),CAPEC-ChiCTRRNC-09000522(https://www.chictr.org.cn/showproj.aspx?proj=9013). 展开更多
关键词 SCHIZOphRENIA Antipsychotic drug Treatment response Prediction model GENETICS EPIGENETICS
原文传递
Proteomic response of Phaeocystis globosa to nitrogen limitation
5
作者 Haisu LIU Ruiwang WEI +2 位作者 Qiangyong LEI Lei CUI Songhui LÜ 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期141-149,共9页
Phaeocystis globosa is an important unicellular eukaryotic alga that can also form colonies.P.globosa can cause massive harmful algal blooms and plays an important role in the global carbon or sulfur cycling.Thus far,... Phaeocystis globosa is an important unicellular eukaryotic alga that can also form colonies.P.globosa can cause massive harmful algal blooms and plays an important role in the global carbon or sulfur cycling.Thus far,the ecophysiology of P.globosa has been investigated by numerous studies.However,the proteomic response of P.globosa to nitrogen depletion remains largely unknown.We compared four protein preparation methods of P.globosa for two-dimensional electrophoresis(2-DE)(Urea/Triton X-100 with trichloroacetic acid(TCA)/acetone precipitation;TCA/acetone precipitation;Radio Immuno Precipitation Assay(RIPA)with TCA/acetone precipitation;and Tris buffer).Results show that the combination of RIPA with TCA/acetone precipitation had a clear gel background and showed the best protein spot separation effect,based on which the proteomic response to nitrogen depletion was studied using 2-DE.In addition,we identified six differentially expressed proteins whose relative abundance increased or decreased more than 1.5-fold(P<0.05).Most proteins could not be identified,which might be attributed to the lack of genomic sequences of P.globosa.Under nitrogen limitation,replication protein-like,RNA ligase,and sn-glycerol-3-phosphate dehydrogenase were reduced,which may decrease the DNA replication level and ATP production in P.globosa cells.The increase of endonucleaseⅢand transcriptional regulator enzyme may affect the metabolic and antioxidant function of P.globosa cells and induce cell apoptosis.These findings provide a basis for further proteomic study of P.globosa and the optimization of protein preparation methods of marine microalgae. 展开更多
关键词 phaeocystis globosa nitrogen limitation proteomic response two-dimensional electrophoresis
下载PDF
Numerical Simulation of the Seismic Response of a Horizontal Storage Tank Based on a SPH-FEM Coupling Method
6
作者 Peilei Yan Endong Guo +1 位作者 HouliWu Liangchao Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1655-1678,共24页
A coupled numerical calculation method combining smooth particle hydrodynamics(SPH)and the finite element method(FEM)was implemented to investigate the seismic response of horizontal storage tanks.Anumericalmodel of a... A coupled numerical calculation method combining smooth particle hydrodynamics(SPH)and the finite element method(FEM)was implemented to investigate the seismic response of horizontal storage tanks.Anumericalmodel of a horizontal storage tank featuring a free liquid surface under seismic action was constructed using the SPH–FEM coupling method.The stored liquid was discretized using SPH particles,while the tank and supports were discretized using the FEM.The interaction between the stored liquid and the tank was simulated by using the meshless particle contact method.Then,the numerical simulation results were compared and analyzed against seismic simulation shaking table test data to validate the method.Subsequently,a series of numerical models,considering different liquid storage volumes and seismic effects,were constructed to obtain time history data of base shear and top center displacement,which revealed the seismic performance of horizontal storage tanks.Numerical simulation results and experimental data showed good agreement,with an error rate of less than 18.85%.And this conformity signifies the rationality of the SPH-FEM coupling method.The base shear and top center displacement values obtained by the coupled SPH-FEM method were only 53.3% to 69.1% of those calculated by the equivalent mass method employed in the current code.As the stored liquid volume increased,the seismic response of the horizontal storage tank exhibited a gradual upward trend,with the seismic response increasing from 73% to 388% for every 35% increase in stored liquid volume.The maximum von Mises stress of the tank and the supports remained below the steel yield strength during the earthquake.The coupled SPH-FEM method holds certain advantages in studying the seismic problems of tanks with complex structural forms,particularly due to the representation of the flow field distribution during earthquakes by involving reservoir fluid participation. 展开更多
关键词 Sph-FEM coupling method horizontal storage tank seismic response SLOSHING
下载PDF
Inflammatory responses in esophageal mucosa before and after laparoscopic antireflux surgery
7
作者 Pelin Ergun Sezgi Kipcak +2 位作者 Nur Selvi Gunel Eser Yildirim Sozmen Serhat Bor 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第3期871-881,共11页
BACKGROUND Currently,the primary treatment for gastroesophageal reflux is acid suppression with proton pump inhibitors,but they are not a cure,and some patients don’t respond well or refuse long-term use.Therefore,al... BACKGROUND Currently,the primary treatment for gastroesophageal reflux is acid suppression with proton pump inhibitors,but they are not a cure,and some patients don’t respond well or refuse long-term use.Therefore,alternative therapies are needed to understand the disease and develop better treatments.Laparoscopic anti-reflux surgery(LARS)can resolve symptoms of these patients and plays a significant role in evaluating esophageal healing after preventing harmful effects.Successful LARS improves typical gastroesophageal reflux symptoms in most patients,main-ly by reducing the exposure time to gastric contents in the esophagus.Amelio-ration of the inflammatory response and a recovery response in the esophageal epithelium is expected following the cessation of the noxious attack.AIM To explore the role of inflammatory biomolecules in LARS and assess the time required for esophageal epithelial recovery.METHODS Of 22 patients with LARS(pre-and post/5.8±3.8 months after LARS)and 25 healthy controls(HCs)were included.All subjects underwent 24-h multichannel intraluminal impedance-pH monitoring and upper gastrointestinal endoscopy,during which esophageal biopsy samples were collected using endoscopic tech-niques.Inflammatory molecules in esophageal biopsies were investigated by reverse transcription-polymerase chain reaction and multiplex-enzyme-linked immunosorbent assay.RESULTS Post-LARS samples showed significant increases in proinflammatory cytokines[interleukin(IL)-1β,interferon-γ,C-X-C chemokine ligand 2(CXCL2)],anti-inflammatory cytokines[CC chemokine ligand(CCL)11,CCL13,CCL17,CCL26,CCL1,CCL7,CCL8,CCL24,IL-4,IL-10],and homeostatic cytokines(CCL27,CCL20,CCL19,CCL23,C-CL25,CXCL12,migration inhibitory factor)compared to both HCs and pre-LARS samples.CCL17 and CCL21 levels were higher in pre-LARS than in HCs(P<0.05).The mRNA expression levels of AKT1,fibroblast growth factor 2,HRAS,and mitogen-activated protein kinase 4 were significantly decreased post-LARS vs pre-LARS.CCL2 and epidermal growth factor gene levels were significantly increased in the pre-LARS compared to the HCs(P<0.05).CONCLUSION The presence of proinflammatory proteins post-LARS suggests ongoing inflammation in the epithelium.Elevated homeostatic cytokine levels indicate cell balance is maintained for about 6 months after LARS.The anti-inflam-matory response post-LARS shows suppression of inflammatory damage and ongoing postoperative recovery. 展开更多
关键词 Anti-reflux surgery Gastroesophageal reflux disease CYTOKINE Inflammatory response ESOphAGUS
下载PDF
Computed tomography-based nomogram of Siewert type Ⅱ/Ⅲ adenocarcinoma of esophagogastric junction to predict response to docetaxel, oxaliplatin and S-1
8
作者 Chuan-Qinyuan Zhou Dan Gao +7 位作者 Yan Gui Ning-Pu Li Wen-Wen Guo Hai-Ying Zhou Rui Li Jing Chen Xiao-Ming Zhang Tian-Wu Chen 《World Journal of Radiology》 2024年第1期9-19,共11页
BACKGROUND Neoadjuvant chemotherapy(NAC)has become the standard care for advanced adenocarcinoma of esophagogastric junction(AEG),although a part of the patients cannot benefit from NAC.There are no models based on ba... BACKGROUND Neoadjuvant chemotherapy(NAC)has become the standard care for advanced adenocarcinoma of esophagogastric junction(AEG),although a part of the patients cannot benefit from NAC.There are no models based on baseline computed tomography(CT)to predict response of Siewert type II or III AEG to NAC with docetaxel,oxaliplatin and S-1(DOS).AIM To develop a CT-based nomogram to predict response of Siewert type II/III AEG to NAC with DOS.METHODS One hundred and twenty-eight consecutive patients with confirmed Siewert type II/III AEG underwent CT before and after three cycles of NAC with DOS,and were randomly and consecutively assigned to the training cohort(TC)(n=94)and the validation cohort(VC)(n=34).Therapeutic effect was assessed by disease-control rate and progressive disease according to the Response Evaluation Criteria in Solid Tumors(version 1.1)criteria.Possible prognostic factors associated with responses after DOS treatment including Siewert classification,gross tumor volume(GTV),and cT and cN stages were evaluated using pretherapeutic CT data in addition to sex and age.Univariate and multivariate analyses of CT and clinical features in the TC were performed to determine independent factors associated with response to DOS.A nomogram was established based on independent factors to predict the response.The predictive performance of the nomogram was evaluated by Concordance index(C-index),calibration and receiver operating characteristics curve in the TC and VC.RESULTS Univariate analysis showed that Siewert type(52/55 vs 29/39,P=0.005),pretherapeutic cT stage(57/62 vs 24/32,P=0.028),GTV(47.3±27.4 vs 73.2±54.3,P=0.040)were significantly associated with response to DOS in the TC.Multivariate analysis of the TC also showed that the pretherapeutic cT stage,GTV and Siewert type were independent predictive factors related to response to DOS(odds ratio=4.631,1.027 and 7.639,respectively;all P<0.05).The nomogram developed with these independent factors showed an excellent performance to predict response to DOS in the TC and VC(C-index:0.838 and 0.824),with area under the receiver operating characteristic curve of 0.838 and 0.824,respectively.The calibration curves showed that the practical and predicted response to DOS effectively coincided.CONCLUSION A novel nomogram developed with pretherapeutic cT stage,GTV and Siewert type predicted the response of Siewert type II/III AEG to NAC with DOS. 展开更多
关键词 Esophagogastric junction ADENOCARCINOMA Neoadjuvant chemotherapy response Tomography X-ray computed Predictor
下载PDF
两种调理剂对水稻土pH值和重金属吸收的影响
9
作者 张璐 文石林 +2 位作者 上官方钦 秦松 张会民 《中国土壤与肥料》 CAS CSCD 北大核心 2024年第1期79-85,共7页
探明两种调理剂对近中性水稻土pH值、重金属有效性和水稻吸收的影响,及其与土壤性质的关系,为调理剂的科学开发及合理施用提供科学依据。选取水淬高炉渣源调理剂(T1)及其腐殖质改性调理剂(T2),分别设置2个施用量梯度(T1L、T1H和T2L、T2... 探明两种调理剂对近中性水稻土pH值、重金属有效性和水稻吸收的影响,及其与土壤性质的关系,为调理剂的科学开发及合理施用提供科学依据。选取水淬高炉渣源调理剂(T1)及其腐殖质改性调理剂(T2),分别设置2个施用量梯度(T1L、T1H和T2L、T2H),通过盆栽试验分析了两种调理剂及不同用量对土壤pH值、有效硅、镉、锌、铜含量,以及水稻籽粒和秸秆镉、锌、铜含量的影响。与对照(CK)相比,2个施用T1调理剂处理土壤pH值分别升高0.64和1.02,2个施用T2调理剂处理pH值分别升高0.27和0.56(P<0.05),土壤pH值随调理剂施用量的增加而增加。T1L和T1H处理土壤有效硅含量与CK相比分别提高5和22倍(P<0.05),且显著高于施用T2调理剂处理。与CK相比,T1H处理土壤有效镉、锌、铜含量分别降低37.21%、45.57%和95.30%(P<0.05);T2L和T2H处理土壤有效锌含量分别降低31.55%和30.67%,有效铜含量分别降低6.53%和19.32%(P<0.05)。与CK相比,T1L和T1H水稻籽粒锌含量分别降低23.44%和18.12%(P<0.05);施用T2调理剂后,籽粒和秸秆锌、铜含量无显著变化。土壤pH值、有效硅含量与土壤有效镉、锌、铜含量呈显著或极显著负相关,土壤有效硅含量与籽粒、秸秆镉含量呈显著负相关。研究表明,在近中性水稻土上施用富含硅的强碱性调理剂,既有利于提高土壤p H值和有效硅含量,又可有效降低土壤重金属有效性及其水稻吸收量。 展开更多
关键词 调理剂 水稻土 ph 有效硅 重金属
下载PDF
基于逆Leidenfrost效应的多孔地聚合物微球孔结构及pH缓冲性能
10
作者 李方贤 王亚松 +2 位作者 张志博 韦江雄 余其俊 《建筑材料学报》 EI CAS CSCD 北大核心 2024年第3期267-274,共8页
以水玻璃、矿渣粉为材料,基于逆Leidenfrost效应制备了多孔地聚合物微球,研究了其孔结构及pH缓冲性能.结果表明:改变水玻璃掺量和水固比可以调控多孔地聚合物微球的孔结构和pH缓冲性能;当水固比为1.0、水玻璃掺量由4%增大至8%时,微球的... 以水玻璃、矿渣粉为材料,基于逆Leidenfrost效应制备了多孔地聚合物微球,研究了其孔结构及pH缓冲性能.结果表明:改变水玻璃掺量和水固比可以调控多孔地聚合物微球的孔结构和pH缓冲性能;当水固比为1.0、水玻璃掺量由4%增大至8%时,微球的孔隙率、中位孔径和孔比表面积均减小,pH值波动范围为1.50~1.90;当水玻璃掺量为4%、水固比由1.0增大至1.2时,微球的孔隙率、中位孔径和孔比表面积均增大,pH值波动范围超过2.00;与双氧水直接发气法制备的多孔地聚合物相比,基于逆Leidenfrost效应制备的多孔地聚合物具有更好的pH缓冲性能和更高的OH-累积浸出量. 展开更多
关键词 逆Leidenfrost效应 矿渣 地聚合物 孔结构 ph缓冲性能
下载PDF
NaCl胁迫下pH值和氮素形态对狗牙根生长及钠钾离子调控的影响
11
作者 陈静波 李丹丹 +4 位作者 郝东利 宗俊勤 姚祥 刘建秀 郭海林 《植物资源与环境学报》 CAS CSCD 北大核心 2024年第2期30-40,共11页
以狗牙根〔Cynodon dactylon(Linn.)Pers.〕品种‘阳江’(‘Yangjiang’)为实验材料、2-(N-吗啡啉)乙磺酸(MES)为pH缓冲剂,采用水培法研究NaCl胁迫下pH值和氮素形态(铵态氮和硝态氮)对狗牙根生长和钠钾离子调控的影响。结果表明:处理1周... 以狗牙根〔Cynodon dactylon(Linn.)Pers.〕品种‘阳江’(‘Yangjiang’)为实验材料、2-(N-吗啡啉)乙磺酸(MES)为pH缓冲剂,采用水培法研究NaCl胁迫下pH值和氮素形态(铵态氮和硝态氮)对狗牙根生长和钠钾离子调控的影响。结果表明:处理1周后,若不添加MES,铵态氮处理组培养液的pH值下降到pH 4.0左右,而硝态氮处理组培养液的pH值则上升到pH 9.0左右;添加20 mmol·L^(-1)MES的铵态氮处理组培养液的pH值也下降到pH 4.0左右,而硝态氮处理组培养液的pH值则接近pH 7.0。与0 mmol·L^(-1)NaCl处理组相比,300 mmol·L^(-1)NaCl处理组狗牙根的枝条长度和枝条干质量显著(P<0.05)下降,而根长度、根干质量、根和叶中Na^(+)含量和Na^(+)/K^(+)比、钠钾选择性转运系数、叶Na^(+)和K^(+)的分泌量及分泌物Na^(+)/K^(+)比总体上显著升高。300 mmol·L^(-1)NaCl胁迫下,硝态氮处理组狗牙根的枝条长度、根长度、根干质量、根冠比、根中Na^(+)含量总体上显著高于铵态氮处理组,而叶中Na^(+)和K^(+)含量及Na^(+)/K^(+)比、叶Na^(+)和K^(+)的分泌量明显低于铵态氮处理组。300 mmol·L^(-1)NaCl胁迫下,20 mmol·L^(-1)MES处理组狗牙根的多数生长指标显著高于0 mmol·L^(-1)MES处理组,而根和叶中Na^(+)和K^(+)含量及Na^(+)/K^(+)比、钠钾选择性转运系数在0和20 mmol·L^(-1)MES处理组间的差异不显著。三因素方差分析结果表明:3个因子的单一和交互作用对多数生长指标、叶中Na^(+)含量和泌盐量相关指标的影响具有统计学意义。研究结果显示:硝态氮能缓解NaCl胁迫对狗牙根的伤害,而用MES缓冲根际酸碱环境对NaCl胁迫下狗牙根生长有一定的促进作用,因此,施用硝态氮或添加MES均有利于提高狗牙根的抗盐性。 展开更多
关键词 狗牙根 NACL胁迫 氮素形态 ph 离子调控 三因素方差分析
下载PDF
pH值调控方法对剩余污泥与柑橘废渣厌氧共发酵产酸影响
12
作者 董姗燕 罗进财 +3 位作者 王欣芸 廖靖莹 孙鸿 朱易春 《中国环境科学》 EI CAS CSCD 北大核心 2024年第1期167-177,共11页
考察不同pH值调控方法对剩余污泥和柑橘废渣共发酵系统的产酸性能影响,结果表明:持续调节pH值为6可以提高共发酵系统的增溶过程,促进糖类物质水解,增强产酸和产甲烷过程,VFA产量和累积甲烷产量分别是空白组的1.36倍和1.25倍;提高共发酵... 考察不同pH值调控方法对剩余污泥和柑橘废渣共发酵系统的产酸性能影响,结果表明:持续调节pH值为6可以提高共发酵系统的增溶过程,促进糖类物质水解,增强产酸和产甲烷过程,VFA产量和累积甲烷产量分别是空白组的1.36倍和1.25倍;提高共发酵系统中水解细菌和发酵产酸细菌的菌群丰度,促使甲烷生成途径从乙酰分解途径转向氢化营养途径.调节初始pH值为10可以有效促进共发酵系统中溶解性有机物的释放和达到快速水解的目的,促进产酸性能,但对产甲烷过程有抑制作用. 展开更多
关键词 剩余污泥 柑橘废渣 共发酵 ph值调节 挥发性脂肪酸
下载PDF
星点设计-效应面法优化白及多糖pH-离子敏感原位凝胶的处方
13
作者 张忠 范依霖 +3 位作者 薛宝玉 蒋琳 仲瑞雪 涂禾 《广东药科大学学报》 CAS 2024年第2期70-75,共6页
目的优化白及多糖pH-离子敏感原位凝胶的处方。方法以去乙酰结冷胶用量、海藻酸钠用量、氯化钙用量、枸橼酸钠与氯化钙的质量比为考察变量,采用单因素实验初步确定各变量的范围。以25℃凝胶前体溶液黏度和37℃胶凝黏度为考察指标,采用... 目的优化白及多糖pH-离子敏感原位凝胶的处方。方法以去乙酰结冷胶用量、海藻酸钠用量、氯化钙用量、枸橼酸钠与氯化钙的质量比为考察变量,采用单因素实验初步确定各变量的范围。以25℃凝胶前体溶液黏度和37℃胶凝黏度为考察指标,采用星点设计-效应面法优选白及多糖pH-离子敏感原位凝胶的处方工艺,并进行预测分析。结果白及多糖pH敏感原位凝胶的最优处方为:去乙酰结冷胶用量为0.50%,海藻酸钠用量为1.10%,氯化钙用量为0.07%,枸橼酸钠与氯化钙的质量比为4∶1。该处方条件下,25℃前体溶液黏度为(704.00±3.00)mPa·s,37℃胶凝黏度为(12544.70±47.33)mPa·s。结论白及多糖pH-离子敏感原位凝胶稳定性好,前体溶液在25℃流动性良好,凝胶强度良好,可为基于白及多糖原位凝胶的后续研究提供实验基础。 展开更多
关键词 星点设计-效应面法 白及多糖 ph敏感原位凝胶 黏度测定
下载PDF
改进和优化黑果枸杞及其制品中花青素测定的pH示差法
14
作者 谭亮 杲秀珍 +2 位作者 王环 赵静 李玉林 《食品与发酵工业》 CAS CSCD 北大核心 2024年第4期267-278,共12页
建立一种基于美国官方分析化学师协会(Association of Official Analytical Chemists,AOAC)方法检测黑果枸杞及其制品中花青素含量的改进pH示差法。考察了黑果枸杞及其制品中花青素的最佳提取和检测条件,通过液相色谱-三重四级杆串联质... 建立一种基于美国官方分析化学师协会(Association of Official Analytical Chemists,AOAC)方法检测黑果枸杞及其制品中花青素含量的改进pH示差法。考察了黑果枸杞及其制品中花青素的最佳提取和检测条件,通过液相色谱-三重四级杆串联质谱法鉴别出黑果枸杞中花青素的具体化学结构,并计算出混合花青素的平均摩尔质量。通过分光光度法测得混合花青素的平均摩尔消光系数,对改进后的pH示差法进行方法学验证和花青素的含量测定。结果显示,最佳提取和检测条件如下:黑果枸杞花青素提取溶剂为盐酸-80%(体积分数)乙醇(3∶97,体积比),料液比为1∶100(g∶mL),提取温度为50℃,提取时间为30 min,缓冲溶液稀释5倍后静置平衡20 min。液相色谱-三重四级杆串联质谱法鉴别黑果枸杞中主要以矮牵牛素类花青素为主(占97.96%),黑果枸杞特有的混合花青素平均摩尔质量为912.7 g/mol,平均摩尔消光系数为29591 L/(mol·cm)。pH示差法改进后能够满足方法学验证要求,固体样品和液体样品最低检出限分别为28.2 mg/100 g、0.282 mg/100 mL。方法改进后花青素提取增长率均大于20%,静置平衡20 min后单次检测结果精密度小于0.3%。以矮牵牛素类花青素代替矢车菊素-3-O-葡萄糖苷计算花青素含量平均提高了2.41倍,能真实地反映黑果枸杞及其制品中花青素的含量。 展开更多
关键词 黑果枸杞及其制品 花青素 AOAC法 ph示差法改进 提取和检测条件优化 液相色谱-三重四级杆串联质谱法鉴别 平均摩尔质量和平均摩尔消光系数优化
下载PDF
pH值为5.5~6.0的柠檬喷雾对ICU禁食禁水患者口渴的影响
15
作者 王小艳 李海军 +2 位作者 张晓雪 张辉 陈敏 《当代护士(下旬刊)》 2024年第4期76-79,共4页
目的观察pH值为5.5~6.0的柠檬喷雾对ICU禁食禁水患者口渴的缓解程度。方法选取2020年1月—12月兰州大学第二医院普外ICU符合纳排标准的140例患者,采用随机数字表法将患者分为试验组与对照组。患者自诉口渴时开始进行干预,试验组患者使... 目的观察pH值为5.5~6.0的柠檬喷雾对ICU禁食禁水患者口渴的缓解程度。方法选取2020年1月—12月兰州大学第二医院普外ICU符合纳排标准的140例患者,采用随机数字表法将患者分为试验组与对照组。患者自诉口渴时开始进行干预,试验组患者使用柠檬水喷雾,对照组患者使用温开水喷雾,分别在干预前、干预后即刻、干预后30 min及干预后1 h对患者口渴程度进行评估,每次间隔4 h重复上述干预措施,干预措施实施前及实施48 h后研究人员对干预效果进行观察和评价,了解干预前及干预48 h后口腔黏膜分级及口腔pH值的变化。将事先配制好的柠檬水(或温开水)装入不透明的小喷壶中,配发给研究人员用于实施干预。结果两组患者的口渴评分组间差异无统计学意义(F=1.260,P>0.05);各个时间点的口渴评分差异有统计学意义(F=166.322,P<0.05);组间效应与时间效应存在交互作用(F=24.821,P<0.05)。试验组患者口腔黏膜分级明显低于对照组(P<0.05);试验组干预后口腔pH值明显升高(P<0.05)。结论使用温开水喷雾和pH值为5.5~6.0的鲜柠檬喷雾均可以缓解ICU禁食禁水患者的口渴症状,但温开水持续时间短暂,需护理人员反复操作,增加护士工作量及患者饮水量,而鲜柠檬喷雾持续时间长,口感好,患者易于接受,可降低口腔黏膜损伤程度,适当提高口腔pH值。 展开更多
关键词 ICU 柠檬喷雾 禁食禁水 口渴 ph
下载PDF
X线定时吞钡检查和24h食管pH监测在食管源性非心源性胸痛诊断中的应用研究
16
作者 赫娟 巴图尔·吐尔地 《现代医用影像学》 2024年第1期124-126,130,共4页
目的:探讨X线定时吞钡检查和24h食管pH监测在食管源性非心源性胸痛诊断中的应用效果。方法:本次研究的对象为200例主诉胸痛和(或)吞咽困难的患者,所有患者均于2020年1月至2022年1月在新疆维吾尔自治区医院消化内科及微创普外科、胸外科... 目的:探讨X线定时吞钡检查和24h食管pH监测在食管源性非心源性胸痛诊断中的应用效果。方法:本次研究的对象为200例主诉胸痛和(或)吞咽困难的患者,所有患者均于2020年1月至2022年1月在新疆维吾尔自治区医院消化内科及微创普外科、胸外科就诊。将200例受试病例分为对照组和研究组,对照组行24h食管pH监测,研究组在24h食管pH监测的基础上行X线定时吞钡检查。比较两组对于胃食管酸反流、食道裂孔疝、贲门失弛缓症和弥漫性食管痉挛的诊断结果。结果:200例食管源性非心源性胸痛患者中,胃食管酸反流93例,食道裂孔疝18例,贲门失弛缓症23例,弥漫性食管痉挛66例。24h食管pH监测方法和24h食管pH监测联合X线定时吞钡检查方法对于胃食管酸反流、食道裂孔疝以及弥漫性食管痉挛的诊断结果无明显差异(P>0.05),而对于贲门失弛缓症,24h食管pH监测方法和24h食管pH监测联合X线定时吞钡检查方法结果显示有明显差异(P<0.05)。结论:24h食管pH监测对于食管源性非心源性胸痛胃食管酸反流有较好的诊断作用,X线定时吞钡检查联合24h食管pH监测对于贲门失弛缓症有较好的诊断作用。 展开更多
关键词 X线定时吞钡检查 24H食管ph监测 食管源性非心源性胸痛 临床诊断
下载PDF
pH对大黄鱼肌原纤维蛋白结构性质及乳化性的影响
17
作者 任中阳 崔雅清 +6 位作者 陈玉峰 石林凡 郝更新 杨燊 邱绪建 刘淑集 翁武银 《水产学报》 CAS CSCD 北大核心 2024年第3期162-171,共10页
为深入探究大黄鱼肌原纤维蛋白(MP)的乳化性,以满足大黄鱼蛋白质高值化开发利用的需求。实验探究了不同pH对大黄鱼MP结构性质及其乳化性的影响。采用pH分别为2、4、6、8、10、12的低盐磷酸缓冲液处理大黄鱼MP,通过SDS-PAGE分析大黄鱼MP... 为深入探究大黄鱼肌原纤维蛋白(MP)的乳化性,以满足大黄鱼蛋白质高值化开发利用的需求。实验探究了不同pH对大黄鱼MP结构性质及其乳化性的影响。采用pH分别为2、4、6、8、10、12的低盐磷酸缓冲液处理大黄鱼MP,通过SDS-PAGE分析大黄鱼MP降解情况,利用接触角测量仪和荧光分光光度计考察其疏水性变化。将不同pH下大黄鱼MP溶液与大豆油以体积比为1∶1的比例经高速均质制备乳液,并对其乳滴电位、粒径以及乳液的乳析指数进行测定,综合分析在不同pH下乳液的稳定性。SDS-PAGE电泳结果表明,在pH 4时,大黄鱼MP条带颜色较浅,在pH 6~12时,肌球蛋白重链条带基本消失,肌动蛋白条带颜色逐渐加深,且在浓缩胶顶部出现了高分子聚集物。对接触角和荧光光谱的综合分析表明,大黄鱼MP疏水性随pH增加而增加。对不同pH下MP乳液特性分析显示,在pH 8时,乳滴带负电且Zeta电位绝对值大[(49.63±1.52)mV]、粒径较小、乳液稳定性较好,而pH 12条件下容易出现破乳,不利于乳液的稳定。在pH 8时,大黄鱼MP结构更有利于提升乳液稳定性。研究表明,在弱碱性条件下更有利于大黄鱼MP形成稳定的乳液体系。pH对大黄鱼MP结构性质和乳化性的影响探究,有望为大黄鱼MP在食品工业中的开发利用提供理论依据。 展开更多
关键词 大黄鱼 肌原纤维蛋白 ph 疏水性 乳化性
原文传递
盐度和pH对平凡舟形藻生长和油脂积累的影响
18
作者 信宏颖 梁金燕 +4 位作者 王馨彤 刘妍 范亚文 陆欣鑫 隋丰阳 《水生生物学报》 CAS CSCD 北大核心 2024年第2期222-231,共10页
为研究盐度和pH对淡水硅藻生长和油脂含量的影响,对一株分离自野外采集水样中的平凡舟形藻(Navicula trivialis)进行研究,通过设置不同盐度0、0.03、0.06、0.12、0.18和0.24 mol/L和不同pH 4.5、6.0、7.5、8.5、9.5和10.5进行胁迫,测定... 为研究盐度和pH对淡水硅藻生长和油脂含量的影响,对一株分离自野外采集水样中的平凡舟形藻(Navicula trivialis)进行研究,通过设置不同盐度0、0.03、0.06、0.12、0.18和0.24 mol/L和不同pH 4.5、6.0、7.5、8.5、9.5和10.5进行胁迫,测定各处理对平凡舟形藻的生长、叶绿素a含量、叶绿素荧光参数和油脂含量的影响。结果表明:盐浓度为0.12 mol/L、pH 7.5时,平凡舟形藻细胞密度和叶绿素a含量最高;盐浓度为0.24 mol/L、pH 7.5时,总脂含量最高,分别为34.93%和33.5%。结果表明,平凡舟形藻对不同盐度和pH的适应性不同,这在一定程度上影响其生长和油脂含量。 展开更多
关键词 盐度 ph 生长 总脂含量 平凡舟形藻
下载PDF
微环境pH值调适对糖尿病足溃疡创面康复的效果评价
19
作者 王一如 白姣姣 +2 位作者 秦雯 缪飞 贾青 《军事护理》 CSCD 北大核心 2024年第5期11-14,共4页
目的评价微环境pH值调适对糖尿病足溃疡的治疗效果。方法选取上海市某三级甲等医院糖尿病足多学科联合门诊就诊患者随机分为两组,对照组接受糖尿病足溃疡常规专科护理,干预组根据创面pH值应用酸性液进行微环境pH值调适。比较两组患者干... 目的评价微环境pH值调适对糖尿病足溃疡的治疗效果。方法选取上海市某三级甲等医院糖尿病足多学科联合门诊就诊患者随机分为两组,对照组接受糖尿病足溃疡常规专科护理,干预组根据创面pH值应用酸性液进行微环境pH值调适。比较两组患者干预前后创面pH值、压疮愈合量表评分及愈合率等。结果干预前两组创面pH值处于碱性范围,干预后第2、4、8周干预组创面pH值和创面面积小于对照组,干预组达到50%愈合所需时间短于对照组,观察期结束时干预组创面愈合率高于对照组,差异均有统计学意义(均P<0.05)。结论对糖尿病足溃疡进行微环境pH值调适可缩短创面愈合时间,改善感染程度,提高创面愈合率,对促进糖尿病足溃疡的修复具有重要作用。 展开更多
关键词 微环境 ph 糖尿病足溃疡 创面愈合
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部