期刊文献+
共找到18,770篇文章
< 1 2 250 >
每页显示 20 50 100
Interfacial activation of alkaline phosphatase induced by hydrophilic metal—organic frameworks
1
作者 Dongyan Chen Yi Xu +3 位作者 Jie Wei Munetaka Oyama Quansheng Chen Xiaomei Chen 《Nano Research》 SCIE EI CSCD 2024年第11期9980-9989,共10页
Encapsulating natural enzymes in metal—organic frameworks (MOFs) can maintain the original biological functions of enzymes in harsh environments. However, the nature of interfacial interactions between a MOF and enzy... Encapsulating natural enzymes in metal—organic frameworks (MOFs) can maintain the original biological functions of enzymes in harsh environments. However, the nature of interfacial interactions between a MOF and enzyme is currently unclear, rendering effective regulation of the biocatalytic activity of the enzyme@MOF composite difficult. Differences in the hydrophilicity of MOF carriers are closely related to the conformational changes and catalytic properties of the enzyme. In this study, the catalytic activity, stability, and conformational changes of alkaline phosphatase (ALP) encapsulated in hydrophilic zeolite imidazolate framework-90 (ZIF-90) and hydrophobic ZIF-8 were systematically investigated using experimental methods and molecular dynamics simulations. The results demonstrated that hydrophilic ZIF-90-encapsulated ALP exhibited superior stability and was 2.22-fold more retained catalytically active than hydrophobic ALP@ZIF-8 after 20 cycles of utilization. Moreover, the hydrophilic interface provided by ZIF-90 effectively regulated the structure of ALP to maintain the optimal catalytic conformation of its active center. The practical application of highly bioactive ALP@ZIF-90 was demonstrated by employing it in a self-calibrated colorimetric/fluorescence dual-mode sensing method for the efficient, reliable, and accurate detection of methyl paraoxon. This study provides new insights for improving enzyme immobilization strategies and promoting the rapid development of enzyme@MOF composites for catalytic and sensing applications. 展开更多
关键词 alkaline phosphatase metal—organic frameworks enzyme immobilization HYDROPHILIC molecular dynamics simulations
原文传递
Analysis of alkaline phosphatase and γ-glutamyltransferase after radiofrequency ablation of primary liver cancer: A retrospective study
2
作者 Wen-Yu Huang Sheng Zheng +7 位作者 Dan Zhu Ying-Lang Zeng Juan Yang Xue-Li Zeng Pei Liu Shun-Ling Zhang Ming Yuan Zhi-Xia Wang 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第9期2860-2869,共10页
BACKGROUND Changes in alkaline phosphatase(ALP)andγ-glutamyltransferase(GGT)levels in patients with primary liver cancer(PLC)after radiofrequency ablation(RFA).Hepatocellular carcinoma is a malignant tumor with high ... BACKGROUND Changes in alkaline phosphatase(ALP)andγ-glutamyltransferase(GGT)levels in patients with primary liver cancer(PLC)after radiofrequency ablation(RFA).Hepatocellular carcinoma is a malignant tumor with high incidence worldwide.As a common local treatment,RFA has attracted much attention for its efficacy and influence on liver function.AIM To investigate the effect of serum ALP and GGT levels on the prognosis of patients with PLC treated by RFA.METHODS The preoperative clinical data of 165 patients who were pathologically or clinically diagnosed with PLC and who received RFA in our hospital between October 2018 and June 2023 were collected.The chi-square test was used to compare the data between groups.The Kaplan-Meier method and Cox regression were used to analyze the associ-ations between serum ALP and GGT levels and overall survival,progression-free survival(PFS)and clinical characteristics of patients before treatment.RESULTS The 1-year survival rates of patients with normal(≤135 U/L)and abnormal(>135 U/L)serum ALP before treatment were 91%and 79%,respectively;the 2-year survival rates were 90%and 68%,respectively;and the 5-year survival rates were 35%and 18%,respectively.The difference between the two groups was statistically significant(P=0.01).Before treatment,the 1-year survival rates of patients with normal serum GGT levels(≤45 U/L)and abnormal serum GGT levels(>45 U/L)were 95%and 87%,the 2-year survival rates were 85%and 71%,and the 5-year survival rates were 37%and 21%,respectively.The difference between the two groups was statist-ically significant(P<0.001).Serum ALP[hazard ratio(HR)=1.766,95%confidence interval(95%CI):1.068-2.921,P=0.027]and GGT(HR=2.312,95%CI:1.367-3.912,P=0.002)is closely related to the overall survival of PLC patients after RF ablation and is an independent prognostic factor.The 1-year PFS rates were 72%and 50%,the 2-year PFS rates were 52%and 21%,and the 5-year PFS rates were 14%and 3%,respectively.The difference between the two groups was statistically significant(P<0001).The 1-year PFS rates were 81%and 56%in patients with normal and abnormal serum GGT levels before treatment,respectively;the 2-year PFS rates were 62%and 35%,respectively;and the 5-year PFS rates were 18%and 7%,respectively,with statistical significance between the two groups(P<0.001).The serum ALP concentration(HR=1.653,95%CI:1.001-2.729,P=0.049)and GGT(HR=1.949,95%CI:1.296-2.930,P=0.001)was closely associated with PFS after RFA in patients with PLC.The proportion of male patients with abnormal ALP levels is high,the Child-Pugh grade of liver function is poor,and the incidence of ascites is high.Among GGT-abnormal patients,the Child-Pugh grade of liver function was poor,the tumor stage was late,the proportion of patients with tumors≥5 cm was high,and the incidence of hepatic encephalopathy was high.CONCLUSION Serum ALP and GGT levels before treatment can be used to predict the prognosis of patients with PLC after RFA,and they have certain guiding significance for the long-term survival of patients with PLC after radiofrequency therapy. 展开更多
关键词 alkaline phosphatase γ-glutamyltransferase Radiofrequency ablation Primary liver cancer Retrospective study
下载PDF
The coupling control of biological precursors and environmental factors onβ-carotane enrichment in alkaline lacustrine source rocks:A case study from the Fengcheng formation in the western Junggar Basin,NW China 被引量:1
3
作者 Mao-Guo Hou Ming Zha +5 位作者 Hua Liu Hai-Lei Liu Jiang-Xiu Qu Ablimit Imin Xiu-Jian Ding Zhong-Fa Jiang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期836-854,共19页
The organic-rich mudstones and dolostones of the Permian Fengcheng Formation(Fm.)are typically alkaline lacustrine source rocks,which are typified by impressively abundantβ-carotane.Abundant β-carotane has been well... The organic-rich mudstones and dolostones of the Permian Fengcheng Formation(Fm.)are typically alkaline lacustrine source rocks,which are typified by impressively abundantβ-carotane.Abundant β-carotane has been well acknowledged as an effective indicator of biological sources or depositional environments.However,the specific biological sources of β-carotane and the coupling control of biological sources and environmental factors on the enrichment of β-carotane in the Fengcheng Fm.remains obscure.Based on a comprehensive investigation of the bulk,molecular geochemistry,and organic petrology of sedimentary rocks and the biochemistry of phytoplankton in modern alkaline lakes,we proposed a new understanding of the biological precursors of β-carotane and elucidated the enrichment mechanism of β-carotane in the Fengcheng Fm.The results show that the biological precursors crucially control the enrichment of β-carotane in the Fengcheng Fm.The haloalkaliphilic cyanobacteria are the primary biological sources of β-carotane,which is suggested by a good positive correlation between the 2-methylhopane index,7-+8-methyl heptadecanes/C_(max),C_(29%),and β-carotane/C_(max)in sedimentary rocks and the predominance of cyanobacteria with abundantβ-carotene in modern alkaline lakes.The enrichment of β-carotane requires the reducing condition,and the paleoredox state that affects the enrichment of β-carotane appears to have a threshold.The paleoclimate conditions do not considerably impact the enrichment of β-carotane,but they have some influence on the water's paleosalinity by affecting evaporation and precipitation.While it does not directly affect the enrichment of β-carotane in the Fengcheng Fm.,paleosalinity does have an impact on the cyanobacterial precursor supply and the preservation conditions. 展开更多
关键词 β-carotane enrichment Cyanobacterial input Environmental impact alkaline lacustrine source rocks The Fengcheng formation
下载PDF
Recent advances and future prospects on Ni_(3)S_(2)-Based electrocatalysts for efficient alkaline water electrolysis 被引量:1
4
作者 Shiwen Wang Zhen Geng +4 位作者 Songhu Bi Yuwei Wang Zijian Gao Liming Jin Cunman Zhang 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第4期659-683,共25页
Green hydrogen(H_(2))produced by renewable energy powered alkaline water electrolysis is a promising alternative to fossil fuels due to its high energy density with zero-carbon emissions.However,efficient and economic... Green hydrogen(H_(2))produced by renewable energy powered alkaline water electrolysis is a promising alternative to fossil fuels due to its high energy density with zero-carbon emissions.However,efficient and economic H_(2) production by alkaline water electrolysis is hindered by the sluggish hydrogen evolution reaction(HER)and oxygen evolution reaction(OER).Therefore,it is imperative to design and fabricate high-active and low-cost non-precious metal catalysts to improve the HER and OER performance,which affects the energy efficiency of alkaline water electrolysis.Ni_(3)S_(2) with the heazlewoodite structure is a potential electrocatalyst with near-metal conductivity due to the Ni–Ni metal network.Here,the review comprehensively presents the recent progress of Ni_(3)S_(2)-based electrocatalysts for alkaline water electrocatalysis.Herein,the HER and OER mechanisms,performance evaluation criteria,preparation methods,and strategies for performance improvement of Ni_(3)S_(2)-based electrocatalysts are discussed.The challenges and perspectives are also analyzed. 展开更多
关键词 alkaline water electrolysis HYDROGEN ELECTROCATALYSTS Ni_(3)S_(2)
下载PDF
An efficient and mild recycling of waste melamine formaldehyde foams by alkaline hydrolysis
5
作者 Shaodi Wu Ning Zhang +7 位作者 Chizhou Wang Xianglin Hou Jie Zhao Shiyu Jia Jiancheng Zhao Xiaojing Cui Haibo Jin Tiansheng Deng 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第5期919-926,共8页
Melamine formaldehyde foam(MFF)generates many poisonous chemicals through the traditional recycling methods for organic resin wastes.Herein,a high MFF degradation ratio of ca.97 wt.%was achieved under the mild conditi... Melamine formaldehyde foam(MFF)generates many poisonous chemicals through the traditional recycling methods for organic resin wastes.Herein,a high MFF degradation ratio of ca.97 wt.%was achieved under the mild conditions(160℃)in a NaOH–H2O system with ammelide and ammeline as the main degradation products.The alkaline solvent had an obvious corrosion effect for MFF,as indicated by scanning electron microscopy(SEM).The reaction process and products distribution were studied by Fourier-transform infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS),and ^(13)C nuclear magnetic resonance(NMR).Besides,the MFF degradation products that have the similar chemical structures and bonding performances to those of melamine can be directly used as the raw material for synthesis of melamine urea-formaldehyde resins(MUFs).Moreover,the degradation system demonstrated here showed the high degradation efficiency after reusing for 7 times.The degradation process generated few harmful pollutants and no pre-or post-treatments were required,which proves its feasibility in the safe removal or recovery of waste MFF. 展开更多
关键词 Melamine formaldehyde foam Degradation alkaline hydrolysis RECYCLING
下载PDF
Soybean(Glycine max)rhizosphere organic phosphorus recycling relies on acid phosphatase activity and specific phosphorusmineralizing-related bacteria in phosphate deficient acidic soils
6
作者 Qianqian Chen Qian Zhao +9 位作者 Baoxing Xie Xing Lu Qi Guo Guoxuan Liu Ming Zhou Jihui Tian Weiguo Lu Kang Chen Jiang Tian Cuiyue Liang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1685-1702,共18页
Bacteria play critical roles in regulating soil phosphorus(P) cycling. The effects of interactions between crops and soil P-availability on bacterial communities and the feedback regulation of soil P cycling by the ba... Bacteria play critical roles in regulating soil phosphorus(P) cycling. The effects of interactions between crops and soil P-availability on bacterial communities and the feedback regulation of soil P cycling by the bacterial community modifications are poorly understood. Here, six soybean(Glycine max) genotypes with differences in P efficiency were cultivated in acidic soils with long-term sufficient or deficient P-fertilizer treatments. The acid phosphatase(AcP) activities, organic-P concentrations and associated bacterial community compositions were determined in bulk and rhizosphere soils. The results showed that both soybean plant P content and the soil AcP activity were negatively correlated with soil organic-P concentration in P-deficient acidic soils. Soil P-availability affected the ɑ-diversity of bacteria in both bulk and rhizosphere soils. However, soybean had a stronger effect on the bacterial community composition, as reflected by the similar biomarker bacteria in the rhizosphere soils in both P-treatments. The relative abundance of biomarker bacteria Proteobacteria was strongly correlated with soil organic-P concentration and AcP activity in low-P treatments. Further high-throughput sequencing of the phoC gene revealed an obvious shift in Proteobacteria groups between bulk soils and rhizosphere soils, which was emphasized by the higher relative abundances of Cupriavidus and Klebsiella, and lower relative abundance of Xanthomonas in rhizosphere soils. Among them, Cupriavidus was the dominant phoC bacterial genus, and it was negatively correlated with the soil organic-P concentration. These findings suggest that soybean growth relies on organic-P mineralization in P-deficient acidic soils, which might be partially achieved by recruiting specific phoCharboring bacteria, such as Cupriavidus. 展开更多
关键词 organic phosphorus acid phosphatase SOYBEAN bacterial community phoC-harboring bacteria RHIZOSPHERE
下载PDF
Maskless fabrication of quasi-omnidirectional V-groove solar cells using an alkaline solution-based method
7
作者 陈兴谦 王燕 +6 位作者 陈伟 刘尧平 邢国光 冯博文 李昊臻 孙纵横 杜小龙 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期236-242,共7页
Silicon passivated emitter and rear contact(PERC) solar cells with V-groove texture were fabricated using maskless alkaline solution etching with in-house developed additive. Compared with the traditional pyramid text... Silicon passivated emitter and rear contact(PERC) solar cells with V-groove texture were fabricated using maskless alkaline solution etching with in-house developed additive. Compared with the traditional pyramid texture, the V-groove texture possesses superior effective minority carrier lifetime, enhanced p–n junction quality and better applied filling factor(FF). In addition, a V-groove texture can greatly reduce the shading area and edge damage of front Ag electrodes when the V-groove direction is parallel to the gridline electrodes. Due to these factors, the V-groove solar cells have a higher efficiency(21.78%) than pyramid solar cells(21.62%). Interestingly, external quantum efficiency(EQE) and reflectance of the V-groove solar cells exhibit a slight decrease when the incident light angle(θ) is increased from 0° to 75°, which confirms the excellent quasi omnidirectionality of the V-groove solar cells. The proposed V-groove solar cell design shows a 2.84% relative enhancement of energy output over traditional pyramid solar cells. 展开更多
关键词 V-groove alkaline etching quasi omnidirectionality silicon solar cell
下载PDF
Surface Deposition of Ni(OH)_(2) and Lattice Distortion Induce the Electrochromic Performance Decay of NiO Films in Alkaline Electrolyte
8
作者 Kejun Xu Liuying Wang +5 位作者 Chaoqun Ge Long Wang Bin Wang Zhuo Wang Chuanwei Zhang Gu Liu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第3期257-267,共11页
NiO,an anodic electrochromic material,has applications in energy-saving windows,intelligent displays,and military camouflage.However,its electrochromic mechanism and reasons for its performance degradation in alkaline... NiO,an anodic electrochromic material,has applications in energy-saving windows,intelligent displays,and military camouflage.However,its electrochromic mechanism and reasons for its performance degradation in alkaline aqueous electrolytes are complex and poorly understood,making it challenging to improve NiO thin films.We studied the phases and electrochemical characteristics of NiO films in different states(initial,colored,bleached and after 8000 cycles)and identified three main reasons for performance degradation.First,Ni(OH)_(2)is generated during electrochromic cycling and deposited on the NiO film surface,gradually yielding a NiO@Ni(OH)_(2)core-shell structure,isolating the internal NiO film from the electrolyte,and preventing ion transfer.Second,the core-shell structure causes the mode of electrical conduction to change from first-to second-order conduction,reducing the efficiency of ion transfer to the surface Ni(OH)_(2)layer.Third,Ni(OH)_(2)and NiOOH,which have similar crystal structures but different b-axis lattice parameters,are formed during electrochromic cycling,and large volume changes in the unit cell reduce the structural stability of the thin film.Finally,we clarified the mechanism of electrochromic performance degradation of NiO films in alkaline aqueous electrolytes and provide a route to activation of NiO films,which will promote the development of electrochromic technology. 展开更多
关键词 alkaline electrolyte ELECTROCHROMISM NiO film performance attenuation mechanism
下载PDF
Collaborative effect between single-atom Re and S vacancy on modulating localized electronic structure of MoS_(2) catalysts for alkaline hydrogen evolution
9
作者 Yajing Zhang Xingkun Wang +1 位作者 Xiangju Song Heqing Jiang 《Nano Research》 SCIE EI CSCD 2024年第11期9507-9517,共11页
Optimizing the catalytic activity and stability of molybdenum disulfide (MoS_(2)) towards alkaline hydrogen evolution reaction (HER) is significant for sustaining green hydrogen. A moderate localized electronic struct... Optimizing the catalytic activity and stability of molybdenum disulfide (MoS_(2)) towards alkaline hydrogen evolution reaction (HER) is significant for sustaining green hydrogen. A moderate localized electronic structure of active sites plays a crucial role in determining the activity and stability of the catalysts, yet how to construct such localized electronic structure still remains indeterminacy. Enlightened by theoretical prediction, herein, the introduction of both single-atom Re and the adjacent S vacancy in MoS_(2) (denoted as Re-MoS_(2)-Vs) exhibits collaborative effect on regulating the localized electronic structure of active sites (viz. Re-(S, Vs)-Mo). Such regulated electronic structure helps to decrease the energy barrier of the water dissociation and optimize hydrogen adsorption energy for enhancing alkaline HER performance. Most importantly, Mo-S bonds in the above local Re-(S, Vs)-Mo configurations are also strengthened for preventing the leaching of Mo and S atoms and then ensuring the long-time stability. Consequently, the deliberately designed Re-MoS_(2)-Vs with a Re coordination number of ~ 5.0 is experimentally verified to exhibit a comparable electrocatalytic performance and robust operational stability over 120 h. This strategy provides a promising guidance for modulating the electronic structure of MoS_(2) based catalysts via double-tuning atomic-scale local configuration for HER applications. 展开更多
关键词 molybdenum disulfide localized electronic structure atomic Re doping S vacancy alkaline hydrogen evolution
原文传递
Protein tyrosine phosphatase non-receptor Ⅱ:A possible biomarker of poor prognosis and mediator of immune evasion in hepatocellular carcinoma
10
作者 Hui-Yuan Li Yi-Ming Jing +5 位作者 Xue Shen Ming-Yue Tang Hong-Hong Shen Xin-Wei Li Zi-Shu Wang Fang Su 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第9期3913-3931,共19页
BACKGROUND The incidence of primary liver cancer is increasing year by year.In 2022 alone,more than 900000 people were diagnosed with liver cancer worldwide,with hepatocellular carcinoma(HCC)accounting for 75%-85%of c... BACKGROUND The incidence of primary liver cancer is increasing year by year.In 2022 alone,more than 900000 people were diagnosed with liver cancer worldwide,with hepatocellular carcinoma(HCC)accounting for 75%-85%of cases.HCC is the most common primary liver cancer.China has the highest incidence and mortality rate of HCC in the world,and it is one of the malignant tumors that seriously threaten the health of Chinese people.The onset of liver cancer is occult,the early cases lack typical clinical symptoms,and most of the patients are already in the middle and late stage when diagnosed.Therefore,it is very important to find new markers for the early detection and diagnosis of liver cancer,improve the therapeutic effect,and improve the prognosis of patients.Protein tyrosine phosphatase non-receptor 2(PTPN2)has been shown to be associated with colorectal cancer,triple-negative breast cancer,non-small cell lung cancer,and prostate cancer,but its biological role and function in tumors remain to be further studied.AIM To combine the results of relevant data obtained from The Cancer Genome Atlas(TCGA)to provide the first in-depth analysis of the biological role of PTPN2 in HCC.METHODS The expression of PTPN2 in HCC was first analyzed based on the TCGA database,and the findings were then verified by immunohistochemical staining,quantitative real-time polymerase chain reaction(qRT-PCR),and immunoblotting.The value of PTPN2 in predicting the survival of patients with HCC was assessed by analyzing the relationship between PTPN2 expression in HCC tissues and clinicopathological features.Finally,the potential of PTPN2 affecting immune escape of liver cancer was evaluated by tumor immune dysfunction and exclusion and immunohistochemical staining.RESULTS The results of immunohistochemical staining,qRT-PCR,and immunoblotting in combination with TCGA database analysis showed that PTPN2 was highly expressed and associated with a poor prognosis in HCC patients.Kyoto Encyclopedia of Genes and Genomes enrichment analysis showed that PTPN2 was associated with various pathways,including cancer-related pathways,the Notch signaling pathway,and the MAPK signaling pathway.Gene Set Enrichment Analysis showed that PTPN2 was highly expressed in various immune-related pathways,such as the epithelial mesenchymal transition process.A risk model score based on PTPN2 showed that immune escape was significantly enhanced in the high-risk group compared with the low-risk group.CONCLUSION This study investigated PTPN2 from multiple biological perspectives,revealing that PTPN2 can function as a biomarker of poor prognosis and mediate immune evasion in HCC. 展开更多
关键词 Protein tyrosine phosphatase non-receptor 2 Hepatocellular carcinoma Immune evasion BIOMARKER Immunotherapy Prognosis
下载PDF
A novel multi-channel porous structure facilitating mass transport towards highly efficient alkaline water electrolysis
11
作者 Xinge Jiang Vasileios Kyriakou +6 位作者 Chen Song Xianbin Wang Sophie Costil Chunming Deng Taikai Liu Tao Jiang Hanlin Liao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期511-518,I0013,共9页
An advantageous porous architecture of electrodes is pivotal in significantly enhancing alkaline water electrolysis(AWE)efficiency by optimizing the mass transport mechanisms.This effect becomes even more pronounced w... An advantageous porous architecture of electrodes is pivotal in significantly enhancing alkaline water electrolysis(AWE)efficiency by optimizing the mass transport mechanisms.This effect becomes even more pronounced when aiming to achieve elevated current densities.Herein,we employed a rapid and scalable laser texturing process to craft novel multi-channel porous electrodes.Particularly,the obtained electrodes exhibit the lowest Tafel slope of 79 mV dec^(-1)(HER)and 49 mV dec^(-1)(OER).As anticipated,the alkaline electrolyzer(AEL)cell incorporating multi-channel porous electrodes(NP-LT30)exhibited a remarkable improvement in cell efficiency,with voltage drops(from 2.28 to 1.97 V)exceeding 300 mV under 1 A cm^(-1),compared to conventional perforated Ni plate electrodes.This enhancement mainly stemmed from the employed multi-channel porous structure,facilitating mass transport and bubble dynamics through an innovative convection mode,surpassing the traditional convection mode.Furthermore,the NP-LT30-based AEL cell demonstrated exceptional durability for 300 h under 1.0 A cm^(-2).This study underscores the capability of the novel multi-channel porous electrodes to expedite mass transport in practical AWE applications. 展开更多
关键词 alkaline water electrolysis Mass transport Bubble dynamics Innovative convection mode Multi-channel porous structure
下载PDF
Influences of different alkaline and acidic diagenetic environments on diagenetic evolution and reservoir quality of alkaline lake shales
12
作者 LI Changzhi GUO Pei +2 位作者 XU Jinghong ZHONG Kai WEN Huaguo 《Petroleum Exploration and Development》 SCIE 2024年第1期97-113,共17页
Thin section and argon-ion polishing scanning electron microscope observations were used to analyze the sedimentary and diagenetic environments and main diagenesis of the Permian Fengcheng Formation shales in differen... Thin section and argon-ion polishing scanning electron microscope observations were used to analyze the sedimentary and diagenetic environments and main diagenesis of the Permian Fengcheng Formation shales in different depositional zones of Mahu Sag in the Junggar Basin,and to reconstruct their differential diagenetic evolutional processes.The diagenetic environment of shales in the lake-central zone kept alkaline,which mainly underwent the early stage(Ro<0.5%)dominated by the authigenesis of Na-carbonates and K-feldspar and the late stage(Ro>0.5%)dominated by the replacement of Na-carbonates by reedmergnerite.The shales from the marginal zone underwent a transition from weak alkaline to acidic diagenetic environments,with the early stage dominated by the authigenesis of Mg-bearing clay and silica and the late stage dominated by the dissolution of feldspar and carbonate minerals.The shales from the transitional zone also underwent a transition from an early alkaline diagenetic environment,evidenced by the formation of dolomite and zeolite,to a late acidic diagenetic environment,represented by the reedmergnerite replacement and silicification of feldspar and carbonate minerals.The differences in formation of authigenic minerals during early diagenetic stage determine the fracability of shales.The differences in dissolution of minerals during late diagenetic stage control the content of free shale oil.Dolomitic shale in the transitional zone and siltstone in the marginal zone have relatively high content of free shale oil and strong fracability,and are favorable“sweet spots”for shale oil exploitation and development. 展开更多
关键词 shale diagenesis alkaline environment authigenic minerals dissolution Permian Fengcheng Formation Mahu Sag Junggar Basin
下载PDF
Alkaline sphingomyelinase deficiency impairs intestinal mucosal barrier integrity and reduces antioxidant capacity in dextran sulfate sodium-induced colitis
13
作者 Ye Tian Xin Li +7 位作者 Xu Wang Si-Ting Pei Hong-Xin Pan Yu-Qi Cheng Yi-Chen Li Wen-Ting Cao Jin-Dong Ding Petersen Ping Zhang 《World Journal of Gastroenterology》 SCIE CAS 2024年第10期1405-1419,共15页
BACKGROUND Ulcerative colitis is a chronic inflammatory disease of the colon with an unknown etiology.Alkaline sphingomyelinase(alk-SMase)is specifically expressed by intestinal epithelial cells,and has been reported ... BACKGROUND Ulcerative colitis is a chronic inflammatory disease of the colon with an unknown etiology.Alkaline sphingomyelinase(alk-SMase)is specifically expressed by intestinal epithelial cells,and has been reported to play an anti-inflammatory role.However,the underlying mechanism is still unclear.AIM To explore the mechanism of alk-SMase anti-inflammatory effects on intestinal barrier function and oxidative stress in dextran sulfate sodium(DSS)-induced colitis.METHODS Mice were administered 3%DSS drinking water,and disease activity index was determined to evaluate the status of colitis.Intestinal permeability was evaluated by gavage administration of fluorescein isothiocyanate dextran,and bacterial translocation was evaluated by measuring serum lipopolysaccharide.Intestinal epithelial cell ultrastructure was observed by electron microscopy.Western blotting and quantitative real-time reverse transcription-polymerase chain reaction were used to detect the expression of intestinal barrier proteins and mRNA,respectively.Serum oxidant and antioxidant marker levels were analyzed using commercial kits to assess oxidative stress levels.RESULTS Compared to wild-type(WT)mice,inflammation and intestinal permeability in alk-SMase knockout(KO)mice were more severe beginning 4 d after DSS induction.The mRNA and protein levels of intestinal barrier proteins,including zonula occludens-1,occludin,claudin-3,claudin-5,claudin-8,mucin 2,and secretory immunoglobulin A,were significantly reduced on 4 d after DSS treatment.Ultrastructural observations revealed progressive damage to the tight junctions of intestinal epithelial cells.Furthermore,by day 4,mitochondria appeared swollen and degenerated.Additionally,compared to WT mice,serum malondialdehyde levels in KO mice were higher,and the antioxidant capacity was significantly lower.The expression of the transcription factor nuclear factor erythroid 2-related factor 2(Nrf2)in the colonic mucosal tissue of KO mice was significantly decreased after DSS treatment.mRNA levels of Nrf2-regulated downstream antioxidant enzymes were also decreased.Finally,colitis in KO mice could be effectively relieved by the injection of tertiary butylhydroquinone,which is an Nrf2 activator.CONCLUSION Alk-SMase regulates the stability of the intestinal mucosal barrier and enhances antioxidant activity through the Nrf2 signaling pathway. 展开更多
关键词 alkaline sphingomyelinase Intestinal mucosal barrier Antioxidant capacity Dextran sulfate sodium-induced colitis nuclear factor erythroid 2-related factor 2
下载PDF
Experimental study on reactions between alkaline basaltic melt and orthopyroxenes: constraints on the evolution of lithospheric mantle in the North China Craton
14
作者 Hanqi He Mingliang Wang Hongfeng Tang 《Acta Geochimica》 EI CAS CSCD 2024年第2期354-365,共12页
The experimental results of the reactions between an alkaline basaltic melt and mantle orthopyroxenes under high-temperature and high-pressure conditions of 1300–1400℃ and 2.0–3.0 GPa using a six-anvil apparatus ar... The experimental results of the reactions between an alkaline basaltic melt and mantle orthopyroxenes under high-temperature and high-pressure conditions of 1300–1400℃ and 2.0–3.0 GPa using a six-anvil apparatus are reported in this paper.The reactions are proposed to simulate the interactions between melts from the asthenospheric mantle and the lithospheric mantle.The starting melt in the experiments was made from the alkaline basalt occurring in Fuxin,Liaoning Province,and the orthopyroxenes were separated from the mantle xenoliths in Damaping,Hebei Province.The results show that clinopyroxenes were formed in all the reactions between the alkaline basaltic melt and orthopyroxenes under the studied P–T conditions.The formation of clinopyroxene in the reaction zone is mainly controlled by dissolution–crystallization,and the chemical compositions of the reacted melt are primarily infl uenced by the diff usion eff ect.Temperature is the most important parameter controlling the reactions between the melt and orthopyroxenes,which has a direct impact on the melting of orthopyroxenes and the diff usion of chemical components in the melt.Temperature also directly controls the chemical compositions of the newly formed clinopyroxenes in the reaction zone and the reacted melt.The formation of clinopyroxenes from the reactions between the alkaline basaltic melt and orthopyroxenes can result in an increase of CaO and Al_(2)O_(3) contents in the rocks containing this mineral.Therefore,the reactions between the alkaline basaltic melt from the asthenospheric mantle and orthopyroxenes from the lithospheric mantle can lead to the evolution of lithospheric mantle in the North China Craton from refractory to fertile with relatively high CaO and Al 2 O 3 contents.In addition,the reacted melts in some runs were transformed from the starting alkaline basaltic into tholeiitic after reactions,indicating that tholeiitic magma could be generated from alkaline basaltic one via reactions between the latter and orthopyroxene. 展开更多
关键词 alkaline basaltic melt ORTHOPYROXENE Melt–mineral reaction High-temperature and high-pressure experiment Genesis of basalt Evolution of lithospheric mantle in the North China Craton
下载PDF
Effects of Metal Ions and Organic Solvents on Alkaline Phosphatase from Rice-field Eel 被引量:7
15
作者 黄毅 唐云明 《Agricultural Science & Technology》 CAS 2008年第2期112-115,共4页
[Objective]The mechanism of alkaline phosphatase(ALP) was studied to promote rice-field eel aquaculture industry. [ Method] The effects of effectors such as multiple metal ions and organic solvents on ALP in viscera... [Objective]The mechanism of alkaline phosphatase(ALP) was studied to promote rice-field eel aquaculture industry. [ Method] The effects of effectors such as multiple metal ions and organic solvents on ALP in viscera of rice-field eel. [ Result] Na^+ and K ^+ didn't generate big influences on enzyme activity;Mg^2+ and Ca^2+ could promote ALP while Li^+,Cu^2+ and Zn^2+ could restrain ALP enzyme activity. Both HPO4^2- and WO4^2- generated by en- zyme catalyzing disodium phenyl phosphate possessed strong inhibitory effects on emzymc, and 9.5 mmol/L HPO4^2 - would make enzyme activity decline by 13% while 9.5 mmol/L WO4^3- would make enzyme decline by 34%. The inhibition types of them were both competitive inhibition on enzyme activity. The organic solvents such as methanol, ethanol,ethylene glycol,isopropannl all generated influences on ALP and the order according to their inhibitory effects was isopropanol 〉 ethanol 〉 methanol 〉 ethylene glycol. [ Conclusion] The inflncnces of various effeetors on ALP aetivity of rice-field eel were studied from dynamics perspective to provide theoretical basis for further clarifying ALP mechanism. 展开更多
关键词 Metal ion Organic solvent alkaline phosphatase Rice-field eel
下载PDF
Digestive enzyme and alkaline phosphatase activities during the early stages of Silurus soldatovi development 被引量:1
16
作者 刘伟 张秀梅 王立波 《Zoological Research》 CAS CSCD 北大核心 2010年第6期627-632,共6页
To provide a theoretical basis to improve the survival and growth rate and optimize diet of sheatfish (Silurus soldatovi), the activities of certain digestive enzymes and alkaline phosphatases were investigated duri... To provide a theoretical basis to improve the survival and growth rate and optimize diet of sheatfish (Silurus soldatovi), the activities of certain digestive enzymes and alkaline phosphatases were investigated during larval development of one-ten day old individuals. Results indicated that sheatfish larva (~ three days after hatching) had high levels of alkaline protease activity, which peaked at five days old and dipped by eight days old, although the trend was generally upward. Acid protease activity at one-eight days old was low, after which it increased rapidly. Amylase activity reached the highest value at five days old, after which it began to decline. Lipase activity fluctuated markedly and showed two peaks at three-four days old and six-eight days old. Larval digestive enzyme activity and alkaline phosphatase activity were higher when fed live food than when fed an artificial diet. Throughout the early development process, alkaline protease activity was higher than acid protease, alkaline protease and amylase specific activity decreased significantly for eight-day-old transition larvae, while acid protease activity increased rapidly. These results indicate that the changes in digestive enzyme activity were relevant to digestive function conversion during fish larvae development. Alkaline phosphatase activity showed an upward trend over the first ten days of life, which indicated that the gastrointestinal function of sheatfish improved gradually. 展开更多
关键词 Silurus soldatovi Larva JUVENILE Digestive enzymes alkaline phosphatase
下载PDF
Construction of single chain Fv antibody against transferrin receptor and its protein fusion with alkaline phosphatase 被引量:12
17
作者 Dao-FengYang Hui-FenZhu +2 位作者 Zhi-HuaWang Guan-XinShen De-YingTian 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第21期3300-3303,共4页
AIM: To construct fusion protein of a single-chain antibody (scFv) against transferrin receptor (TfR) with alkaline phosphatase(AP). METHODS: The VH-linker-VL,namely scFv gene,was prepared by amplifying the VH and VL ... AIM: To construct fusion protein of a single-chain antibody (scFv) against transferrin receptor (TfR) with alkaline phosphatase(AP). METHODS: The VH-linker-VL,namely scFv gene,was prepared by amplifying the VH and VL genes from plasmid pGEM-T-VH and pGEM-T-VL with splicing overlap extension polymerase chain reaction (SOE PCR). After the ScFv gene was modified by 5/71 and Not I,it was subcloned into the secretory expression vector pUC19/119, and then was transformed into E.coli TG1.The positive colonies were screened by colony PCR and their expressions were induced by IPTG.ScFv gene was gained by digesting ScFv expression vector pUC19/119 with 5/71 and NotI restriction enzymes, then subcloned into expression vector pDAP2, followed by transformation in E.coli TG1.The positive colonies were selected by bacterial colony PCR.The expression of fusion protein (scFv-AP) was induced by IPTG.Its activity was detected by enzyme immunoassay. The molecular weights of scFv and scFv-AP were measured by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). RESULTS: The product of SOE PCR formed a band of 700 bp in agarose gel electrophoresis. SDS-PAGE demonstrated the molecular weight of scFv was 27 ku.Immunofluorescent assay (IFA) demonstrated its reactivity with TfR.The molecular weight of scFv-AP was 75 ku.Enzyme immunoassay showed that scFv-AP could specifically bind to human TfR and play AP activity. CONCLUSION: We have successfully prepared the anti-human TfR scFv and constructed the fusion protein of scFv and AP.It is promising for immunological experiments. 展开更多
关键词 Transferrin receptor Fusion protein Single chain Fv antibody alkaline phosphatase Primary hepatocarcinoma
下载PDF
Model based on γ-glutamyltransferase and alkaline phosphatase for hepatocellular carcinoma prognosis 被引量:9
18
作者 Xin-Sen Xu Yong Wan +9 位作者 Si-Dong Song Wei Chen Run-Chen Miao Yan-Yan Zhou Ling-Qiang Zhang Kai Qu Si-Nan Liu Yue-Lang Zhang Ya-Feng Dong Chang Liu 《World Journal of Gastroenterology》 SCIE CAS 2014年第31期10944-10952,共9页
AIM: To determine the prognostic value of alkaline phosphatase (ALP) and &#x003b3;-glutamyltransferase (GGT) for hepatocellular carcinoma (HCC) .
关键词 alkaline phosphatase γ-Glutamyltransferase PROGNOSIS Hepatocellular carcinoma
下载PDF
Interplay between intestinal alkaline phosphatase, diet, gut microbes and immunity 被引量:6
19
作者 Mehrbod Estaki Daniella DeCoffe Deanna L Gibson 《World Journal of Gastroenterology》 SCIE CAS 2014年第42期15650-15656,共7页
Intestinal alkaline phosphatase (IAP) plays an essential role in intestinal homeostasis and health through interactions with the resident microbiota, diet and the gut. IAP&#x02019;s role in the intestine is to dep... Intestinal alkaline phosphatase (IAP) plays an essential role in intestinal homeostasis and health through interactions with the resident microbiota, diet and the gut. IAP&#x02019;s role in the intestine is to dephosphorylate toxic microbial ligands such as lipopolysaccharides, unmethylated cytosine-guanosine dinucleotides and flagellin as well as extracellular nucleotides such as uridine diphosphate. IAP&#x02019;s ability to detoxify these ligands is essential in protecting the host from sepsis during acute inflammation and chronic inflammatory conditions such as inflammatory bowel disease. Also important in these complications is IAP&#x02019;s ability to regulate the microbial ecosystem by forming a complex relationship between microbiota, diet and the intestinal mucosal surface. Evidence reveals that diet alters IAP expression and activity and this in turn can influence the gut microbiota and homeostasis. IAP&#x02019;s ability to maintain a healthy gastrointestinal tract has accelerated research on its potential use as a therapeutic agent against a multitude of diseases. Exogenous IAP has been shown to have beneficial effects when administered during ulcerative colitis, coronary bypass surgery and sepsis. There are currently a handful of human clinical trials underway investigating the effects of exogenous IAP during sepsis, rheumatoid arthritis and heart surgery. In light of these findings IAP has been marked as a novel agent to help treat a variety of other inflammatory and infectious diseases. The purpose of this review is to highlight the essential characteristics of IAP in protection and maintenance of intestinal homeostasis while addressing the intricate interplay between IAP, diet, microbiota and the intestinal epithelium. 展开更多
关键词 Intestinal alkaline phosphatase Inflammation Infection LIPOPOLYSACCHARIDES Inflammatory disease Intestinal microbiota DIET
下载PDF
Intestinal alkaline phosphatase in the colonic mucosa of children with inflammatory bowel disease 被引量:7
20
作者 Kriszta Molnár dám Vannay +8 位作者 Beáta Szebeni Nóra Fanni Bánki Erna Sziksz ron Cseh Hajnalka Gyrffy Péter László Lakatos Mária Papp András Arató Gábor Veres 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第25期3254-3259,共6页
AIM: To investigate intestinal alkaline phosphatase (iAP) in the intestinal mucosa of children with inflammatory bowel disease (IBD). METHODS: Colonic biopsy samples were taken from 15 newly diagnosed IBD patien... AIM: To investigate intestinal alkaline phosphatase (iAP) in the intestinal mucosa of children with inflammatory bowel disease (IBD). METHODS: Colonic biopsy samples were taken from 15 newly diagnosed IBD patients and from 10 healthy controls. In IBD patients, specimens were obtainedboth from inflamed and non-inflamed areas. The lAP mRNA and protein expression was determined by reverse transcription-polymerase chain reaction and Western blotting analysis, respectively. Tissue localiza- tion of lAP and Toll-like receptor (TLR) 4 was investi- gated by immunofluorescent staining. RESULTS: The lAP protein level in the inflamed muco- sa of children with Crohn's disease (CD) and ulcerative colitis (UC) was significantly decreased when compared with controls (both P 〈 0.05). Similarly, we found a significantly decreased level of lAP protein in the in- flamed mucosa in CD compared with non-inflamed mucosa in CD (P 〈 0.05). In addition, the iAP protein level in inflamed colonic mucosa in patients with UC was decreased compared with non-inflamed mucosa in patients with CD (P 〈 0.05). lAP protein levels in the non-inflamed mucosa of patients with CD were similar to controls, lAP mRNA expression in inflamed colonic mucosa of children with CD and UC was not significant- ly different from that in non-inflamed colonic mucosa with CD. Expression of lAP mRNA in patients with non- inflamed mucosa and in controls were similar. Co-local- ization of lAP with TLR4 showed intense staining with a dotted-like pattern, lAP was present in the inflamed and non-inflamed mucosa of patients with CD, UC, and in control biopsy specimens, irrespective of whether it was present in the terminal ileum or in the colon. However, the fluorescent signal of TLR4 was more pro- nounced in the colon compared with the terminal ileum in all groups studied. CONCLUSION: Lower than normal lAP protein levels in inflamed mucosa of IBD patients may indicate a role for lAP in inflammatory lesions in IBD. Based on our results, administration of exogenous lAP enzyme to pa- tients with the active form of IBD may be a therapeutic option. 展开更多
关键词 Intestinal alkaline phosphatase Toll-like recep-tor Colonic biopsy CHILDREN Inflammatory bowel disease
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部