期刊文献+
共找到18,944篇文章
< 1 2 250 >
每页显示 20 50 100
Linear paired electrolysis of furfural to furoic acid at both anode and cathode in a multiple redox mediated system
1
作者 Xinxin Li Linchuan Cong +4 位作者 Haibo Lin Fangbing Liu Xiangxue Fu Hai-Chao Xu Nan Lin 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期104-113,共10页
Implementing a new energy-saving electrochemical synthesis system with high commercial value is a strategy of the sustainable development for upgrading the bulk chemicals preparation technology in the future.Here,we r... Implementing a new energy-saving electrochemical synthesis system with high commercial value is a strategy of the sustainable development for upgrading the bulk chemicals preparation technology in the future.Here,we report a multiple redox-mediated linear paired electrolysis system,combining the hydrogen peroxide mediated cathode process with the I2 mediated anode process,and realize the conversion of furfural to furoic acid in both side of the dividedflow cell simultaneously.By reasonably controlling the cathode potential,the undesired water splitting reaction and furfural reduction side reactions are avoided.Under the galvanostatic electrolysis,the two-mediated electrode processes have good compatibility,which reduce the energy consumption by about 22%while improving the electronic efficiency by about 125%.This system provides a green electrochemical synthesis route with commercial prospects. 展开更多
关键词 Multiple redox mediated system Linear paired electrolysis FURFURAL Furoic acid
下载PDF
Dynamic Non-Invasive Detection of NADH Based on Blood Flow-Mediated Skin Fluorescence (FMSF) Method
2
作者 Peng Liu Tengfei Bi +2 位作者 Gongzhi Du Long Yan Huayi Hou 《Open Journal of Applied Sciences》 2024年第6期1437-1453,共17页
Nicotinamide adenine dinucleotide (NADH/NAD+) is involved in important biochemical reactions in human metabolism, including participation in energy production by mitochondria. The changes in fluorescence intensity as ... Nicotinamide adenine dinucleotide (NADH/NAD+) is involved in important biochemical reactions in human metabolism, including participation in energy production by mitochondria. The changes in fluorescence intensity as a function of time in response to blocking and releasing of blood flow in a forearm are used as a measure of oxygen transport with blood to the tissue, which directly correlates with the skin microcirculation status. In this paper, a non-invasive dynamic monitoring system based on blood flow-mediated skin fluorescence (FMSF) technology is developed to monitor the NADH fluorescence intensity of skin tissue during the process of blocking reactive hyperemia. Simultaneously, laser speckle contrast imaging (LSCI) and laser Doppler flowmetry (LDF) were used to observe blood flow, blood oxygen saturation (SOt2) and relative amount of hemoglobin (rHb) during the measurement process, which helped to explore NADH dynamics relevant physiological changes. A variety of parameters have been derived to describe NADH fluorescence curve based on the FMSF device. The experimental results are conducive to understanding the NADH measurement and the physiological processes related to it, which help FMSF to be a great avenue for in vivo physiological, clinical and pharmacological research on mitochondrial metabolism. 展开更多
关键词 Reduced Nicotinamide Adenine Dinucleotide (NADH) Flow-mediated Skin Fluorescence (FMSF) Laser Doppler Flowmetry (LDF) Blood Flow
下载PDF
Microglia-mediated T cell infiltration drives neurodegeneration in tauopathy 被引量:2
3
作者 Xiaoying Chen 《四川生理科学杂志》 2023年第3期564-564,共1页
Extracellular deposition of amyloid-βas neuritic plaques and intracellular accumulation of hyperphosphorylated,aggregated tau as neurofibrillary tangles are two of the characteristic hallmarks of Alzheimer's dise... Extracellular deposition of amyloid-βas neuritic plaques and intracellular accumulation of hyperphosphorylated,aggregated tau as neurofibrillary tangles are two of the characteristic hallmarks of Alzheimer's disease1,2.The regional progression of brain atrophy in Alzheimer's disease highly correlates with tau accumulation but not amyloid deposition3-5,and the mechanisms of tau-mediated neurodegeneration remain elusive. 展开更多
关键词 tau mediated AMYLOID
下载PDF
Pro-resolving lipid mediator reduces amyloid-β42–induced gene expression in human monocyte–derived microglia
4
作者 Ying Wang Xiang Zhang +6 位作者 Henrik Biverstål Nicolas GBazan Shuai Tan Nailin Li Makiko Ohshima Marianne Schultzberg Xiaofei Li 《Neural Regeneration Research》 SCIE CAS 2025年第3期873-886,共14页
Specialized pro-resolving lipid mediators including maresin 1 mediate resolution but the levels of these are reduced in Alzheimer's disease brain, suggesting that they constitute a novel target for the treatment o... Specialized pro-resolving lipid mediators including maresin 1 mediate resolution but the levels of these are reduced in Alzheimer's disease brain, suggesting that they constitute a novel target for the treatment of Alzheimer's disease to prevent/stop inflammation and combat disease pathology. Therefore, it is important to clarify whether they counteract the expression of genes and proteins induced by amyloid-β. With this objective, we analyzed the relevance of human monocyte–derived microglia for in vitro modeling of neuroinflammation and its resolution in the context of Alzheimer's disease and investigated the pro-resolving bioactivity of maresin 1 on amyloid-β42–induced Alzheimer's disease–like inflammation. Analysis of RNA-sequencing data and secreted proteins in supernatants from the monocyte-derived microglia showed that the monocyte-derived microglia resembled Alzheimer's disease–like neuroinflammation in human brain microglia after incubation with amyloid-β42. Maresin 1 restored homeostasis by down-regulating inflammatory pathway related gene expression induced by amyloid-β42 in monocyte-derived microglia, protection of maresin 1 against the effects of amyloid-β42 is mediated by a re-balancing of inflammatory transcriptional networks in which modulation of gene transcription in the nuclear factor-kappa B pathway plays a major part. We pinpointed molecular targets that are associated with both neuroinflammation in Alzheimer's disease and therapeutic targets by maresin 1. In conclusion, monocyte-derived microglia represent a relevant in vitro microglial model for studies on Alzheimer's disease-like inflammation and drug response for individual patients. Maresin 1 ameliorates amyloid-β42–induced changes in several genes of importance in Alzheimer's disease, highlighting its potential as a therapeutic target for Alzheimer's disease. 展开更多
关键词 Alzheimer's disease amyloid-β maresin MICROGLIA MONOCYTE NEUROINFLAMMATION resolution RNA-sequencing specialized pro-resolving lipid mediator
下载PDF
Resilience provides mediating effect of resilience between fear of progression and sleep quality in patients with hematological malignancies
5
作者 Yuan Tian Ying-Li Wang 《World Journal of Psychiatry》 SCIE 2024年第4期541-552,共12页
BACKGROUND Hematological tumors are common malignant tumors,with high morbidity and mortality rates.Most patients with hematological malignancies develop sleep disorders that seriously affect their life and health bec... BACKGROUND Hematological tumors are common malignant tumors,with high morbidity and mortality rates.Most patients with hematological malignancies develop sleep disorders that seriously affect their life and health because of acute onset of disease,rapid progression,high recurrence rates,complex treatment methods,and treatment costs.AIM To explore the mediating effect of resilience on fear of disease progression and sleep quality in patients with hematological malignancies.METHODS A cross-sectional analysis of 100 patients with hematological malignancies,treated in the First Affiliated Hospital of Jinzhou Medical University between August 2022 and August 2023,was conducted.Patients were assessed using a general data survey,a simplified scale for the fear of progression(FoP)of disease,a resilience scale,and the Pittsburgh Sleep Quality Index.Statistical analysis was conducted to determine the relationship between various patient characteristics and FoP,resilience,and sleep quality.Spearman’s correlation analysis was used to examine the correlations between mental resilience,FoP,and sleep quality.RESULTS The total FoP score mean value in patients with hematological malignancies was 38.09±5.16;the total resilience score mean value was 40.73±7.04;and the Pittsburgh Sleep Quality Index score mean value was 10.72±1.90.FoP,resilience,and sleep quality of the patients were associated with family per capita monthly income and patient education level(P<0.05).Spearman correlation analysis revealed that FoP was negatively correlated with resilience and sleep quality scores(r=-0.560,-0.537,P<0.01),respectively,and resilience was significantly associated with sleep quality scores(r=0.688,P<0.01).Mediation analysis showed that the mediating effect of resilience between FoP and sleep quality in patients with hematological malignancies was-0.100 and accounted for 50.51%of the total effect.This indicated that FoP directly and indirectly affected sleep quality through the mesomeric effect of resilience.CONCLUSION Resilience is an intermediary variable between FoP and sleep quality in patients with hematological malignancies.Medical staff should evaluate and follow-up FoP and resilience to implement measures to improve sleep quality. 展开更多
关键词 RESILIENCE Blood tumor Fear of progression Sleep quality mediating effect
下载PDF
Association of education with cholelithiasis and mediating effects of cardiometabolic factors:A Mendelian randomization study
6
作者 Chang-Lei Li Yu-Kun Liu +1 位作者 Ying-Ying Lan Zu-Sen Wang 《World Journal of Clinical Cases》 SCIE 2024年第20期4272-4288,共17页
BACKGROUND Education,cognition,and intelligence are associated with cholelithiasis occurrence,yet which one has a prominent effect on cholelithiasis and which cardiometabolic risk factors mediate the causal relationsh... BACKGROUND Education,cognition,and intelligence are associated with cholelithiasis occurrence,yet which one has a prominent effect on cholelithiasis and which cardiometabolic risk factors mediate the causal relationship remain unelucidated.AIM To explore the causal associations between education,cognition,and intelligence and cholelithiasis,and the cardiometabolic risk factors that mediate the associations.METHODS Applying genome-wide association study summary statistics of primarily European individuals,we utilized two-sample multivariable Mendelian randomization to estimate the independent effects of education,intelligence,and cognition on cholelithiasis and cholecystitis(FinnGen study,37041 and 11632 patients,respectively;n=486484 participants)and performed two-step Mendelian randomization to evaluate 21 potential mediators and their mediating effects on the relationships between each exposure and cholelithiasis.RESULTS Inverse variance weighted Mendelian randomization results from the FinnGen consortium showed that genetically higher education,cognition,or intelligence were not independently associated with cholelithiasis and cholecystitis;when adjusted for cholelithiasis,higher education still presented an inverse effect on cholecystitis[odds ratio:0.292(95%CI:0.171-0.501)],which could not be induced by cognition or intelligence.Five out of 21 cardiometabolic risk factors were perceived as mediators of the association between education and cholelithiasis,including body mass index(20.84%),body fat percentage(40.3%),waist circumference(44.4%),waist-to-hip ratio(32.9%),and time spent watching television(41.6%),while time spent watching television was also a mediator from cognition(20.4%)and intelligence to cholelithiasis(28.4%).All results were robust to sensitivity analyses.CONCLUSION Education,cognition,and intelligence all play crucial roles in the development of cholelithiasis,and several cardiometabolic mediators have been identified for prevention of cholelithiasis due to defects in each exposure. 展开更多
关键词 CHOLELITHIASIS Mendelian randomization mediation analysis Education attainment Cardiometabolic risk factors COGNITION INTELLIGENCE
下载PDF
Mediating role of social support in dysphoria,despondency,and quality of life in patients undergoing maintenance hemodialysis
7
作者 Xiang Zhou Hong Jiang +4 位作者 Yi-Peng Zhou Xiao-Yu Wang Hai-Yan Ren Xue-Fei Tian Qing-Qing Zhang 《World Journal of Psychiatry》 SCIE 2024年第3期409-420,共12页
BACKGROUND Dysphoria and despondency are prevalent psychological issues in patients undergoing Maintenance Hemodialysis(MHD)that significantly affect their quality of life(QOL).High levels of social support can signif... BACKGROUND Dysphoria and despondency are prevalent psychological issues in patients undergoing Maintenance Hemodialysis(MHD)that significantly affect their quality of life(QOL).High levels of social support can significantly improve the physical and mental well-being of patients undergoing MHD.Currently,there is limited research on how social support mediates the relationship between dysphoria,despondency,and overall QOL in patients undergoing MHD.It is imperative to investigate this mediating effect to mitigate dysphoria and despondency in patients undergoing MHD,ultimately enhancing their overall QOL.AIM To investigate the mediating role of social support in relationships between dysphoria,despondency,and QOL among patients undergoing MHD.METHODS Participants comprised 289 patients undergoing MHD,who were selected using a random sampling approach.The Social Support Rating Scale,Self-Rating Anxiety Scale,Self-Rating Depression Scale,and QOL Scale were administered.Correlation analysis was performed to examine the associations between social support,dysphoria,despondency,and QOL in patients undergoing MHD.To assess the mediating impact of social support on dysphoria,despondency,and QOL in patients undergoing MHD,a bootstrap method was applied.RESULTS Significant correlations among social support,dysphoria,despondency,and quality in patients undergoing MHD were observed(all P<0.01).Dysphoria and despondency negatively correlated with social support and QOL(P<0.01).Dysphoria and despondency had negative predictive impacts on the QOL of patients undergoing MHD(P<0.05).The direct effect of dysphoria on QOL was statistically significant(P<0.05).Social support mediated the relationship between dysphoria and QOL,and this mediating effect was significant(P<0.05).Similarly,the direct effect of despondency on QOL was significant(P<0.05).Moreover,social support played a mediating role between despondency and QOL,with a significant mediating effect(P<0.05).CONCLUSION These findings suggest that social support plays a significant mediating role in the relationship between dysphoria,despondency,and QOL in patients undergoing MHD. 展开更多
关键词 Maintenance hemodialysis Social support DYSPHORIA Despondency Quality of life mediating effect
下载PDF
1995—2011年国际网络传播研究发展状况分析——以SSCI之Journal of Computer-Mediated Communication为例
8
作者 彭虹 肖尧中 齐向楠 《符号与传媒》 2013年第1期3-30,22+21+23-30,共28页
本文以SSCI之Journal of Computer-MediatedCommunication1995年至2011年的全部文章为分析对象,以研究主题、方法和理论为分析框架,以内容分析、定性、定量等方法为分析手段,力图在此基础上探讨国际网络传播研究的发展趋势。分析发... 本文以SSCI之Journal of Computer-MediatedCommunication1995年至2011年的全部文章为分析对象,以研究主题、方法和理论为分析框架,以内容分析、定性、定量等方法为分析手段,力图在此基础上探讨国际网络传播研究的发展趋势。分析发现:网络被传播领域认定为新媒体,但网络绝不仅仅是一种媒体,所以不能只用传播理论对其进行研究;在时间之轴上,每个研究主题的意旨都在不断流变;网络传播的研究方法正在多元化、综合化的演进中打破关于研究方法的传统归类体例;建构网络传播的理论,是一个漫长的过程,在此过程中,互动、涌现和非线性乃是建构网络传播理论大厦的重要支撑。 展开更多
关键词 JCMC 网络传播 研究主题 研究方法
下载PDF
Quinone-mediated decolorization of sulfonated azo dyes by cells and cell extracts from Sphingomonas xenophaga 被引量:4
9
作者 JIAO Ling, LU Hong, ZHOU Jiti, WANG Jing School of Environmental and Biological Science and Technology, Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), Dalian University of Technology, Dalian 116024, China. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第4期503-508,共6页
The effects of various quinone compounds on the decolorization rates of sulfonated azo dyes by Sphingomonas xenophaga QYY were investigated. The results showed that anthraquinone-2-sulfonate (AQS) was the most effec... The effects of various quinone compounds on the decolorization rates of sulfonated azo dyes by Sphingomonas xenophaga QYY were investigated. The results showed that anthraquinone-2-sulfonate (AQS) was the most effective redox mediator and AQS reduction was the rate-limited step of AQS-mediated decolorization of sulfonated azo dyes. Based on AQS biological toxicity tests, it was assumed that AQS might enter the cells and kill them. In the cytoplasmic extracts from strain QYY, AQS more effectively increased decolorization rates of sulfonated azo dyes than other quinone compounds. In addition, we found a NADH/FMN-dependent AQS reductase using nondenaturing polyacrylamide gel electrophoresis (Native-PAGE). 展开更多
关键词 redox mediator sulfonated azo dyes Sphingomonas xenophaga REDUCTASE
下载PDF
Estrogen-mediated downregulation of HIF-1αsignaling in B lymphocytes influences postmenopausal bone loss 被引量:6
10
作者 Xianyi Meng Zhen Lin +11 位作者 Shan Cao Iga Janowska Koshiro Sonomoto Darja Andreev Knab Katharina Jinming Wen Karl Xaver Knaup Michael Sean Wiesener Gerhard Krönke Marta Rizzi Georg Schett Aline Bozec 《Bone Research》 SCIE CAS CSCD 2022年第2期326-337,共12页
In the bone marrow, B cells and bone-resorbing osteoclasts colocalize and form a specific microenvironment. How B cells functionally influence osteoclasts and bone architecture is poorly understood. Using genetically ... In the bone marrow, B cells and bone-resorbing osteoclasts colocalize and form a specific microenvironment. How B cells functionally influence osteoclasts and bone architecture is poorly understood. Using genetically modified mice and highthroughput analyses, we demonstrate that prolonged HIF-1α signaling in B cells leads to enhanced RANKL production and osteoclast formation. In addition, deletion of HIF-1α in B cells prevents estrogen deficiency-induced bone loss in mice.Mechanistically, estrogen controls HIF-1α protein stabilization through HSP70-mediated degradation in bone marrow B cells.The stabilization of HIF-1α protein in HSP70-deficient bone marrow B cells promotes RANKL production and osteoclastogenesis.Induction of HSP70 expression by geranylgeranylacetone(GGA) administration alleviates ovariectomy-induced osteoporosis.Moreover, RANKL gene expression has a positive correlation with HIF1 A expression in human B cells. In conclusion, HIF-1αsignaling in B cells is crucial for the control of osteoclastogenesis, and the HSP70/HIF-1α axis may serve as a new therapeutic target for osteoporosis. 展开更多
关键词 mediated LYMPHOCYTES stabilization
下载PDF
Macrophage-derived small extracellular vesicles promote biomimetic mineralized collagen-mediated endogenous bone regeneration 被引量:5
11
作者 Anqi Liu Shanshan Jin +7 位作者 Cuicui Fu Shengji Cui Ting Zhang Lisha Zhu Yu Wang Steve G.F.Shen Nan Jiang Yan Liu 《International Journal of Oral Science》 SCIE CAS CSCD 2020年第4期317-326,共10页
Macrophages play an important role in material-related immune responses and bone formation,but the functionality of macrophage-derived extracellular vesicles(EVs)in material-mediated bone regeneration is still unclear... Macrophages play an important role in material-related immune responses and bone formation,but the functionality of macrophage-derived extracellular vesicles(EVs)in material-mediated bone regeneration is still unclear.Here,we evaluated intracellular communication through small extracellular vesicles(sEVs)and its effects on endogenous bone regeneration mediated by biomimetic intrafibrillarly mineralized collagen(IMC).After implantation in the bone defect area,IMC generated more neobone and recruited more mesenchymal stem cells(MSCs)than did extrafibrillarly mineralized collagen(EMC).More CD63+CD90+and CD63+CD163+cells were detected in the defect area in the IMC group than in the EMC group.To determine the functional roles of sEVs,extracellular vesicles from macrophages cultured on different mineralized collagen were isolated,and they showed no morphological differences.However,macrophage-derived sEVs in the IMC group showed an enhanced Young’s modulus and exerted beneficial effects on the osteogenic differentiation of bone marrow MSCs by increasing the expression of the osteoblastic differentiation markers BMP2,BGLAP,COL1,and OSX and calcium nodule formation.Mechanistically,sEVs from IMC-treated macrophages facilitated MSC osteogenesis through the BMP2/Smad5 pathway,and blocking sEV secretion with GW4869 significantly impaired MSC proliferative,immunomodulative and osteogenic potential.Taken together,these findings show that macrophage-derived sEVs may serve as an emerging functional tool in biomaterial-mediated endogenous bone regeneration. 展开更多
关键词 ENDOGENOUS CD63 mediated
下载PDF
Human survival and immune mediated mitophagy in neuroplasticity disorders 被引量:3
12
作者 Ian James Martins 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第4期735-735,共1页
Dear editors,Neurodegenerative diseases are now associated with the global obesity and diabetes epidemic in the developing and developed world.Neurodegenerative diseases are a heterogeneous group of disorders with com... Dear editors,Neurodegenerative diseases are now associated with the global obesity and diabetes epidemic in the developing and developed world.Neurodegenerative diseases are a heterogeneous group of disorders with complex factors such as neurohumoral,endocrine and environmental factors involved in induction of these neurodegenerative diseases.The future of science and medicine in neurodegenerative diseases is now dependent on nutritional genomics with insulin resistance a major factor in the induction of neurodegenerative diseases.Nutritional genomics now involves the anti-aging gene Sirtuin 1(Sirt 1)that is important to the prevention of insulin resistance with its critical involvement in the immune system(Martins,2018a,b).Sirt 1 inactivation leads to toxic immune reactions connected to the acceleration of neuron death in various communities.Appetite control with relevance to immunometabolism has become of critical importance to the treatment of neurodegeneration(Figure 1).Nutritional diets activate the heat shock gene Sirt 1 to prevent the increase in heat shock proteins connected to autoimmune disease,mitophagy(Martins,2018a,b)and irreversible programmed cell death in global populations(Figure 1). 展开更多
关键词 Human SURVIVAL IMMUNE mediated MITOPHAGY NEUROPLASTICITY DISORDERS
下载PDF
An Empirical Analysis of the Effect of Text-Based Computer-Mediated Communication on Communicative Competence
13
作者 王剑娜 《海外英语》 2016年第8期225-228,共4页
It has been suggested that text-based computer-mediated communication can help learners to use target language both in classrooms and in social contexts.It’s necessary to investigate the effect of text-based CMC on l... It has been suggested that text-based computer-mediated communication can help learners to use target language both in classrooms and in social contexts.It’s necessary to investigate the effect of text-based CMC on learners’communicative competence by conducting the method of systematic review.The findings implied that text-based CMC settings allowed learners to interact.The interaction provided learners with more opportunities to develop their communicative competence of target language. 展开更多
关键词 text-based computer-mediated communication(CMC) second language acquisition(SLA) COMMUNICATIVE compe
下载PDF
mpaired flow-mediated vasodilatation in Asian Indians with erectile dysfunction 被引量:1
14
作者 Tanuj Bhatia Aditya Kapoor +8 位作者 Jatinder Kumar Archana Sinha Priyadarshi Ranjan Sudeep Kumar Naveen Garg Satyendra-Tewari Aneesh Srivastava Rakesh Kapoor Pravin K Goel 《Asian Journal of Andrology》 SCIE CAS CSCD 2013年第5期652-657,共6页
Endothelial dysfunction is the postulated link between coronary artery disease (CAD) and erectile dysfunction (ED). Brachial artery flow-mediated vasodilatation (FMD) is a non-invasive surrogate marker for endot... Endothelial dysfunction is the postulated link between coronary artery disease (CAD) and erectile dysfunction (ED). Brachial artery flow-mediated vasodilatation (FMD) is a non-invasive surrogate marker for endothelial function assessment. Despite Asian Indians representing a considerable global CAD burden, data on FMD and ED in these patients are lacking. Of the 225 patients undergoing coronary angiography, 72% had ED (assessed using the International Index of Erectile Function (IIEF-5) questionnaire); ED was moderate to severe in 61% of the patients. ED patients had a higher incidence of severe and diffuse angiographic CAD, a greater number of coronary vessels involved and a lower mean brachial artery FMD (6.40%±4.60% vs. 9.10%±4.87%, P〈0.001) compared to non-ED patients. A progressive reduction in FMD was noted with increasing severity of ED. Impaired FMD ( ≤ 5.5%) was twice as common in ED patients (52% vs. 24% without ED). Patients with impaired FMD had higher ED prevalence (85% vs. 62%) and lower mean I IEF-5 scores compared to those with normal FMD. Impaired FMD was a significant ED predictor independent of other risk factors (odds ratio, 2.33; 95% confidence interval: 0.59-9.23; P=0.03). An inverse correlation between FMD and ED severity was observed (r=-0.22; P=0.004). ED is common among Asian Indians with angiographically documented CAD. Patients with ED have impaired FMD independent of other risk factors, suggesting that endothelial dysfunction is the underlying pathophysiology. Urologists and cardiologists need to be aware of the association between ED, CAD and endothelial dysfunction. 展开更多
关键词 Asian Indians brachial artery flow mediated vasodilatation erectile dysfunction (ED)
下载PDF
Seed-mediated synthesis of dendritic platinum nanostructures with high catalytic activity for aqueous-phase hydrogenation of acetophenone 被引量:3
15
作者 Yuan Yuan Yusuf Valentino Kaneti +5 位作者 Minsu Liu Fangzhu Jin Danielle Frances Kennedy Xuchuan Jiang Jun Huang Aibing Yu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2015年第5期660-668,共9页
This work reports a facile and efficient seed-mediated method for the synthesis of dendritic platinum (Pt) nanoparticles (NPs) at low temperatures of 55-60 ℃ in water, using L-ascorbic acid as a reducing agent an... This work reports a facile and efficient seed-mediated method for the synthesis of dendritic platinum (Pt) nanoparticles (NPs) at low temperatures of 55-60 ℃ in water, using L-ascorbic acid as a reducing agent and sodium citrate as a capping agent. It is found that the dendritic Pt NPs (10-150 nm) are composed of tiny Pt nanocrystals, which nucleate and grow through the introduced smaller Pt seeds with diameters of 3-5 nm. Further investigation shows that the dendritic Pt nanostructures display excellent catalytic performance in an aqueous-phase aromatic ketone hydrogenation reaction, including: (i) acetophenone conversion rate of 〉 90%, with smaller dendritic Pt NPs (10-46 nm) offering a higher conversion efficiency; (ii) high chemoselectivity toward carbonyl group (90.6%-91.5%), e.g., the selectivity to l-phenylethanol is -90.1% with nearly 100% acetophenone conversion for 10 nm dendritic Pt NPs within 60 rain, under mild reaction conditions (20 ℃, 1.5 bar H2 pressure, and 1.5 tool% catalyst). The high catalytic activity, selectivity and stability of the dendritic Pt nanostructures under the organic solvent-free conditions make them promising for many potential applications in green catalytic conversion of hydrophilic biomass derived compounds. 展开更多
关键词 Dendritic Pt nanoparticles Aqueous-phase hydrogenation Acetophenone conversionSeed mediated synthesis
下载PDF
Mechanical tibial loading remotely suppresses brain tumors by dopamine-mediated downregulation of CCN4 被引量:1
16
作者 Yao Fan Rongrong Zha +17 位作者 Tomohiko Sano Xinyu Zhao Shengzhi Liu Mark D.Woollam Di Wu Xun Sun Kexin Li Motoki Egi Fangjia Li Kazumasa Minami Amanda P.Siegel Takashi Horiuchi Jing Liu Mangilal Agarwal Akihiro Sudo Harikrishna Nakshatri Bai-Yan Li Hiroki Yokota 《Bone Research》 SCIE CAS CSCD 2021年第3期313-322,共10页
Mechanical loading to the bone is known to be beneficial for bone homeostasis and for suppressing tumor-induced osteolysis in the loaded bone.However,whether loading to a weight-bearing hind limb can inhibit distant t... Mechanical loading to the bone is known to be beneficial for bone homeostasis and for suppressing tumor-induced osteolysis in the loaded bone.However,whether loading to a weight-bearing hind limb can inhibit distant tumor growth in the brain is unknown.We examined the possibility of bone-to-brain mechanotransduction using a mouse model of a brain tumor by focusing on the response to Lrp5-mediated Wnt signaling and dopamine in tumor cells.The results revealed that loading the tibia with elevated levels of tyrosine hydroxylase,a rate-limiting enzyme in dopamine synthesis,markedly reduced the progression of the brain tumors.The simultaneous application of fluphenazine(FP),an antipsychotic dopamine modulator,enhanced tumor suppression.Dopamine and FP exerted antitumor effects through the dopamine receptors DRD1 and DRD2,respectively.Notably,dopamine downregulated Lrp5 via DRD1 in tumor cells.A cytokine array analysis revealed that the reduction in CCN4 was critical for loading-driven,dopamine-mediated tumor suppression.The silencing of Lrp5 reduced CCN4,and the administration of CCN4 elevated oncogenic genes such as MMP9,Runx2,and Snail.In summary,this study demonstrates that mechanical loading regulates dopaminergic signaling and remotely suppresses brain tumors by inhibiting the Lrp5-CCN4 axis via DRD1,indicating the possibility of developing an adjuvant bone-mediated loading therapy. 展开更多
关键词 DOPAMINE mediated ELEVATED
下载PDF
MYB41,MYB107,and MYC2 promote ABA-mediated primary fatty alcohol accumulation via activation of AchnFAR in wound suberization in kiwifruit 被引量:1
17
作者 Xiaopeng Wei Linchun Mao +2 位作者 Xiaobo Wei Ming Xia Changjie Xu 《Horticulture Research》 SCIE 2020年第1期1666-1675,共10页
Wound damage triggers the accumulation of abscisic acid(ABA),which induces the expression of a large number of genes involved in wound suberization in plants.Fatty acyl-CoA reductase(FAR)catalyzes the generation of pr... Wound damage triggers the accumulation of abscisic acid(ABA),which induces the expression of a large number of genes involved in wound suberization in plants.Fatty acyl-CoA reductase(FAR)catalyzes the generation of primary fatty alcohols by the reduction of fatty acids in suberin biosynthesis.However,the regulatory effects of transcription factors(TFs)on AchnFAR in response to ABA are unexplored.In this study,kiwifruit AchnFAR displayed a biological function analogous to that of FAR in transiently overexpressed tobacco(Nicotiana benthamiana)leaves.The positive role of TFs,including AchnMYB41,AchnMYB107,and AchnMYC2,in the regulation of AchnFAR was identified.The three TFs could individually bind to the AchnFAR promoter to activate gene transcription in yeast one-hybrid and dualluciferase assays.Transient overexpression of TFs in tobacco leaves resulted in the upregulation of aliphatic synthesis genes(including FAR)and the increase in aliphatics,including primary alcohols,α,ω-diacids,ω-hydroxyacids,and fatty acids.Moreover,exogenous ABA treatment elevated TF-mediated AchnFAR expression and the accumulation of primary alcohols.Conversely,fluridone,an inhibitor of ABA biosynthesis,suppressed the expression of AchnFAR and TF genes and reduced the formation of primary alcohols.The results indicate that AchnMYB41,AchnMYB107,and AchnMYC2 activate AchnFAR transcription to promote ABA-mediated primary alcohol formation in wound suberization in kiwifruit. 展开更多
关键词 WOUND mediated ELEVATED
下载PDF
Opening Moves Involved in Text-based Computer-Mediated-Communication (CMC) by Chinese Adults
18
作者 李莉华 《海外英语》 2011年第3X期257-258,260,共3页
The development of science and technology has made it not only possible but very convenient for people living in different parts of the world to communicate with each other, thus bringing forth a new form of communica... The development of science and technology has made it not only possible but very convenient for people living in different parts of the world to communicate with each other, thus bringing forth a new form of communication: computer-mediated communication (CMC). Text-based CMC is one of the most popular forms of CMC in which people send instant messages to others in different settings. Since this mode of interaction combines features of both the written and spoken language (Greenfield & Subrahmanyam, 2003), it's of great interest whether it follows the same sequential rule as the telephone conversation. However, compared to telephone conversations, computer-mediated communication has received much less attention, let alone text-based CMC. The existing body of literature mostly focuses on content analysis and linguistic features but neglects the sequential organization of such interaction (Paolillo, 1999; Greenfield and Subrahmanyam, 2003; Herring, 1999). In light of this, this paper examines the opening moves of instant message exchanges among Chinese adults in an attempt to find out the unique features characterizing the way they open an online chat. The framework that was chosen for data analysis was the sequential model proposed by Schegloff for American telephone openings. 展开更多
关键词 computer-mediated communication(CMC) Text-based CMC OPENING MOVES instant message exchanges on line chat sequential model
下载PDF
Angiogenesis in a 3D model containing adipose tissue stem cells and endothelial cells is mediated by canonical Wnt signaling 被引量:6
19
作者 Xiaoxiao Cai Jing Xie +5 位作者 Yang Yao Xiangzhu Cun Shiyu Lin Taoran Tian Bofeng Zhu Yunfeng Lin 《Bone Research》 SCIE CAS CSCD 2017年第4期330-342,共13页
Adipose-derived stromal cells (ASCs) have gained great attention in regenerative medicine. Progress in our understanding of adult neovascularization further suggests the potential of ASCs in promoting vascular regen... Adipose-derived stromal cells (ASCs) have gained great attention in regenerative medicine. Progress in our understanding of adult neovascularization further suggests the potential of ASCs in promoting vascular regeneration, although the specific cues that stimulate their angiogenic behavior remain controversial In this study, we established a three-dimensional (3D) angiogenesis model by co-culturing ASCs and endothelial cells (ECs) in collagen gel and found that ASC-EC-instructed angiogenesis was regulated by the canonical Wnt pathway. Furthermore, the angiogenesis that occurred in implants collected after injections of our collagen gel- based 3D angiogenesis model into nude mice was confirmed to be functional and also regulated by the canonical Wnt pathway. Wnt regulation of angiogenesis involving changes in vessel length, vessel density, vessel sprout, and connection numbers occurred in our system. Wnt signaling was then shown to regulate ASC- mediated paracrine signaling during angiogenesis through the nuclear translocation of β-catenin after its cytoplasmic accumulation in both ASCs and ECs. This translocation enhanced the expression of nuclear cofactor Lef-1 and cyclin D1 and activated the angiogenic transcription of vascular endothelial growth factor A (VEGFA), basic fibroblast growth factor (bFGF), and insulin-like growth factor 1 (IGF-1). The angiogenesis process in the 3D collagen model appeared to follow canonical Wnt signaling, and this model can help us understand the importance of the canonical Wnt pathway in the use of ASCs in vascular regeneration. 展开更多
关键词 Angiogenesis in a 3D model containing adipose tissue stem cells and endothelial cells is mediated by canonical Wnt signaling WNT
下载PDF
PRELIMINARY STUDY OF RETROVIRAL MEDIATED TRANSFER OF THE HUMAN mdr-1 GENE INTO MURINE AND HUMAN HEMATOPOIETIC STEM/PROGENITOR CELLS 被引量:1
20
作者 冯凯 裴雪涛 +5 位作者 王立生 高文谦 徐黎 王玉芝 李梁 吴祖泽 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1997年第4期36-39,共4页
To investigate the characteristics of multidrugresistance and transplantation of modified stem/ progenitor cells by multidrugresistant gene (mdr1 gene), we established PA317/MDR1 cell line which producing retroviruse... To investigate the characteristics of multidrugresistance and transplantation of modified stem/ progenitor cells by multidrugresistant gene (mdr1 gene), we established PA317/MDR1 cell line which producing retroviruses by transfecting the retroviral vector PHaMDR1/A into packging cell line PA317 by Lipofectin. The virus titer of the supernatants was 1.2×105 cfu/ml. We transfected the murine hematopietic cells collected from 5FU pretreated mice and they showed the ability to reconstitute the longterm hematopoiesis of preirradiated mice. After 4 months, both of bone marrow cells and peripheral blood cells of transplanted mice still contained mdr1 gene. We also transfered mdr1 gene into human bone marrow CD34+ cells selected by using magnetic cell sorting system. PCR analysis showed that transduced CD34+ cells maintained the mdr1 cDNA. A fraction of CFUGM originated from transfected CD34+ cells had the charactor of resistance to Taxol. It is indicated that mdr1 gene can be transduced into murine and human stem/proginitor cells through retroviral mediated gene transfer and it protects the transfected cells from cytotoxic drugs. 展开更多
关键词 Stem/progenitor cells mdr1 gene Gene transfer Retroviral mediated
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部