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Unveiling DNA methylation in Alzheimer’s disease:a review of array-based human brain studies 被引量:1
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作者 Victoria Cunha Alves Eva Carro Joana Figueiro-Silva 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第11期2365-2376,共12页
The intricacies of Alzheimer’s disease pathogenesis are being increasingly illuminated by the exploration of epigenetic mechanisms,particularly DNA methylation.This review comprehensively surveys recent human-centere... The intricacies of Alzheimer’s disease pathogenesis are being increasingly illuminated by the exploration of epigenetic mechanisms,particularly DNA methylation.This review comprehensively surveys recent human-centered studies that investigate whole genome DNA methylation in Alzheimer’s disease neuropathology.The examination of various brain regions reveals distinctive DNA methylation patterns that associate with the Braak stage and Alzheimer’s disease progression.The entorhinal cortex emerges as a focal point due to its early histological alterations and subsequent impact on downstream regions like the hippocampus.Notably,ANK1 hypermethylation,a protein implicated in neurofibrillary tangle formation,was recurrently identified in the entorhinal cortex.Further,the middle temporal gyrus and prefrontal cortex were shown to exhibit significant hypermethylation of genes like HOXA3,RHBDF2,and MCF2L,potentially influencing neuroinflammatory processes.The complex role of BIN1 in late-onset Alzheimer’s disease is underscored by its association with altered methylation patterns.Despite the disparities across studies,these findings highlight the intricate interplay between epigenetic modifications and Alzheimer’s disease pathology.Future research efforts should address methodological variations,incorporate diverse cohorts,and consider environmental factors to unravel the nuanced epigenetic landscape underlying Alzheimer’s disease progression. 展开更多
关键词 Alzheimer’s disease ANK1 BIN1 DNA methylation epigenome-wide association studies HOXA3 MCF2L RHBDF2
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Pretreatment and analysis techniques development of TKIs in biological samples for pharmacokinetic studies and therapeutic drug monitoring
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作者 Lan Chen Yuan Zhang +5 位作者 Yi-Xin Zhang Wei-Lai Wang De-Mei Sun Peng-Yun Li Xue-Song Feng Yue Tan 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第4期439-459,共21页
Tyrosine kinase inhibitors(TKIs)have emerged as the first-line small molecule drugs in many cancer therapies,exerting their effects by impeding aberrant cell growth and proliferation through the modulation of tyrosine... Tyrosine kinase inhibitors(TKIs)have emerged as the first-line small molecule drugs in many cancer therapies,exerting their effects by impeding aberrant cell growth and proliferation through the modulation of tyrosine kinase-mediated signaling pathways.However,there exists a substantial inter-individual variability in the concentrations of certain TKIs and their metabolites,which may render patients with compromised immune function susceptible to diverse infections despite receiving theoretically efficacious anticancer treatments,alongside other potential side effects or adverse reactions.Therefore,an urgent need exists for an up-to-date review concerning the biological matrices relevant to bioanalysis and the sampling methods,clinical pharmacokinetics,and therapeutic drug monitoring of different TKIs.This paper provides a comprehensive overview of the advancements in pretreatment methods,such as protein precipitation(PPT),liquid-liquid extraction(LLE),solid-phase extraction(SPE),micro-SPE(μ-SPE),magnetic SPE(MSPE),and vortex-assisted dispersive SPE(VA-DSPE)achieved since 2017.It also highlights the latest analysis techniques such as newly developed high performance liquid chromatography(HPLC)and high-resolution mass spectrometry(HRMS)methods,capillary electrophoresis(CE),gas chromatography(GC),supercritical fluid chromatography(SFC)procedures,surface plasmon resonance(SPR)assays as well as novel nanoprobes-based biosensing techniques.In addition,a comparison is made between the advantages and disadvantages of different approaches while presenting critical challenges and prospects in pharmacokinetic studies and therapeutic drug monitoring. 展开更多
关键词 TKIs Microextraction technique HRMS methods Pharmacokinetic studies Therapeutic drug monitoring
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Recent advances and key perspectives of in-situ studies for oxygen evolution reaction in water electrolysis
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作者 Yi Wang Zichen Xu +1 位作者 Xianhong Wu Zhong-Shuai Wu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第10期1497-1517,共21页
Electricity-driven water splitting to produce hydrogen is one of the most efficient ways to alleviate energy crisis and environmental pollution problems,in which the anodic oxygen evolution reaction(OER)is the key hal... Electricity-driven water splitting to produce hydrogen is one of the most efficient ways to alleviate energy crisis and environmental pollution problems,in which the anodic oxygen evolution reaction(OER)is the key half-reaction of performance-limiting in water splitting.Given the complicated reaction process and surface reconstruction of the involved catalysts under actual working conditions,unraveling the real active sites,probing multiple reaction intermediates and clarifying catalytic pathways through in-situ characterization techniques and theoretical calculations are essential.In this review,we summarize the recent advancements in understanding the catalytic process,unlocking the water oxidation active phase and elucidating catalytic mechanism of water oxidation by various in-situ characterization techniques.Firstly,we introduce conventionally proposed traditional catalytic mechanisms and novel evolutionary mechanisms of OER,and highlight the significance of optimal catalytic pathways and intrinsic stability.Next,we provide a comprehensive overview of the fundamental working principles,different detection modes,applicable scenarios,and limitations associated with the in-situ characterization techniques.Further,we exemplified the in-situ studies and discussed phase transition detection,visualization of speciation evolution,electronic structure tracking,observation of reaction active intermediates,and monitoring of catalytic products,as well as establishing catalytic structure-activity relationships and catalytic mechanism.Finally,the key challenges and future perspectives for demystifying the water oxidation process are briefly proposed. 展开更多
关键词 In-situ studies Water splitting Oxygen evolution reaction Catalytic mechanism
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Epistasis-aware genome-wide association studies provide insights into the efficient breeding of high-yield and high-quality rice
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作者 Xiaogang He Zirong Li +6 位作者 Sicheng Guo Xingfei Zheng Chunhai Liu Zijie Liu Yongxin Li Zheming Yuan Lanzhi Li 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第8期2541-2556,共16页
Marker-assisted selection(MAS)and genomic selection(GS)breeding have greatly improved the efficiency of rice breeding.Due to the influences of epistasis and gene pleiotropy,ensuring the actual breeding effect of MAS a... Marker-assisted selection(MAS)and genomic selection(GS)breeding have greatly improved the efficiency of rice breeding.Due to the influences of epistasis and gene pleiotropy,ensuring the actual breeding effect of MAS and GS is still a difficult challenge to overcome.In this study,113 indica rice varieties(V)and their 565 testcross hybrids(TC)were used as the materials to investigate the genetic basis of 12 quality traits and nine agronomic traits.The original traits and general combining ability of the parents,as well as the original traits and midparent heterosis of TC,were subjected to genome-wide association analysis.In total,381 primary significantly associated loci(SAL)and 1,759 secondary SALs that had epistatic interactions with these primary SALs were detected.Among these loci,322 candidate genes located within or nearby the SALs were screened,204 of which were cloned genes.A total of 39 MAS molecular modules that are beneficial for trait improvement were identified by pyramiding the superior haplotypes of candidate genes and desirable epistatic alleles of the secondary SALs.All the SALs were used to construct genetic networks,in which 91 pleiotropic loci were investigated.Additionally,we estimated the accuracy of genomic prediction in the parent V and TC by incorporating either no SALs,primary SALs,secondary SALs or epistatic effect SALs as covariates.Although the prediction accuracies of the four models were generally not significantly different in the TC dataset,the incorporation of primary SALs,secondary SALs,and epistatic effect SALs significantly improved the prediction accuracies of 5(26%),3(16%),and 11(58%)traits in the V dataset,respectively.These results suggested that SALs and epistatic effect SALs identified based on an additive genotype can provide considerable predictive power for the parental lines.They also provide insights into the genetic basis of complex traits and valuable information for molecular breeding in rice. 展开更多
关键词 rice genome-wide association study EPISTASIS gene pleiotropy maker-associated selection genome selection
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Gut microbiota changes associated with frailty in older adults:A systematic review of observational studies
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作者 Na-Na Wen Li-Wei Sun +1 位作者 Qian Geng Guo-Hua Zheng 《World Journal of Clinical Cases》 SCIE 2024年第35期6815-6825,共11页
BACKGROUND Frailty is a complex aging-related syndrome characterized by a cumulative loss of physiological reserve and increased vulnerability to adverse clinical outcomes,including falls,disability,incapacity and dea... BACKGROUND Frailty is a complex aging-related syndrome characterized by a cumulative loss of physiological reserve and increased vulnerability to adverse clinical outcomes,including falls,disability,incapacity and death.While an increasing number of studies suggest that the gut microbiota may play a key role in the pathophy-siology of frailty,direct evaluation of the association between gut microbiome alterations and frailty in older adults remains limited.AIM Seven electronic databases(China National Knowledge Infrastructure,VIP,SinoMed,Wanfang,PubMed,Web of Science and EMBASE)were searched for articles published before October 31,2023 to identify observational studies that compared the microbiomes of older adults with and without frailty.The diversity and composition of the gut microbiota were the main outcomes used to analyze the associations of changes in the gut microbiota with frailty in older adults.The quality of the included studies was assessed via the Newcastle-Ottawa Scale and the Agency for Healthcare Research and Quality.RESULTS Eleven observational studies with 912 older adults were included in this review.Consistent results revealed a significant difference in the gut microbiota composition between frail and non-frail older adults,with a significant decrease inαdiversity and a significant increase inβdiversity in frail older adults.The pooled results revealed that at the phylum level,four microbiota(Actinobacteria,Proteo-bacteria,Verrucomicrobia and Synergistetes)were significantly enriched,and two microbiota(Firmicutes and Fusobacteria)were significantly depleted in frail older adults.At the family level,the results consistently revealed that the abundances of 6 families,most of which belong to the Actinobacteria or Proteo-bacteria phylum,were greater in frail than in non-frail older adults.At the genus or species level,consistent results from more than two studies revealed that the abundances of the genera Prevotella,Faecalibacterium,and Roseburia were significantly lower in frail older adults;individual studies revealed that the abundances of some genera or species(e.g.,Megamonas,Blautia,and Megasphaera)were significantly lower,whereas those of other genera or species(e.g.,Bifidobacterium,Oscillospira,Ruminococcus and Pyramidobacter)were significantly greater in frail older adults.CONCLUSION This systematic review suggests that changes in the gut microbiota are associated with frailty in older adults,which is commonly reflected by a reduction in beneficial species and an increase in pathogenic species.However,further studies are needed to confirm these findings. 展开更多
关键词 FRAILTY Gut microbiota Observational study Older adults Systematic review
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A Research Conception on Indigenous Chinese Leadership:Based on Comparative Case Studies on Political Elites in Ancient China
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作者 LI Yongrui HUANG Shiqing 《Chinese Business Review》 2024年第3期95-113,共19页
Due to the complexity of leadership and its variability across situations,it is suggested that research on leadership should focus on attempts to understand leadership in specific situations or roles,and develop local... Due to the complexity of leadership and its variability across situations,it is suggested that research on leadership should focus on attempts to understand leadership in specific situations or roles,and develop local knowledge about leadership in each situation or role.This paper validates the possibility and importance of building indigenous leadership theories from historical perspective.We demonstrated how to carry out research on indigenous Chinese leadership from a historical perspective by comparative case studies using historical data.Based on the principles of typicalness,representativeness,and comparativeness,we selected six counterparts of political elites in ancient China as comparative cases,which includes Guan Zhong&Shang Yang(organizational reformer),Liu Bang&Xiang Yu(entrepreneur),Li Shimin&Qin Shihuang(intergenerational transition successor),Zhuge Liang&Zeng Guofan(professional manager),Lu Su&Zhang Juzheng(mess-to-order maker),and Zuo Zongtang&Wang Anshi(national dream driver).The paper aims to develop indigenous leadership theory specific to Chinese mental states and culture. 展开更多
关键词 historical perspective indigenous leadership political elites in ancient China comparative case study qualitative study
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Exploring the Path of Shantytown Renewal Based on the Theory of Environment-behavior Studies: A Case Study of the Northwest Area of Saihantala in Baotou City
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作者 ZHANG Miao TIAN Jiaqi GONG Rui 《Journal of Landscape Research》 2024年第2期61-65,68,共6页
The application of environment-behavior studies plays an important role in studying the renewal of shantytowns.One of the most humane ways of renewal is designing and constructing the necessary urban spatial environme... The application of environment-behavior studies plays an important role in studying the renewal of shantytowns.One of the most humane ways of renewal is designing and constructing the necessary urban spatial environment from the perspective of human daily behavior.Most of the shantytown renovation projects currently carried out in China are mainly focused on demolition and reconstruction,which not only incurs high costs but also damages the original social structure and economic model.During the process of shantytown renewal,it should improve the urban landscape,living environment,and life quality of residents,and ensure the daily life of shantytown residents without increasing their economic burden,and preserve the traces of urban development.In order to achieve this goal,it should explore the renewal strategies of shantytowns from the perspective of environment-behavior studies through behavior maps,on-site research,and literature review.Updating and design from a human perspective often achieve faster and better development;the renewal of shantytowns should be a bottom-up approach and start from a grassroots perspective,completing the renovation design through the composition of the population and behavioral patterns. 展开更多
关键词 Environment-behavior studies Shantytown renewal Economic type Bottom view BOTTOM-UP
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Genetic Parameters and Genome-Wide Association Studies for Body Size Traits of Shuxuan Cattle in China
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作者 Wei WANG Maozhong FU +12 位作者 Donghui FANG Yi SHI Fang HE Yueda AG Zhimin LIAO Xiaodong DENG Xiaoqin MA Liqiong LI Ling ZENG Meixu FU Hongchuan CHEN Jia GAN Jun YI 《Asian Agricultural Research》 2024年第11期44-48,共5页
In domestic cattle,the body size traits have important implications in terms of breed characteristics and production performance.Shuxuan cattle is a dual-purpose breed mainly raised in Sichuan province,China,for which... In domestic cattle,the body size traits have important implications in terms of breed characteristics and production performance.Shuxuan cattle is a dual-purpose breed mainly raised in Sichuan province,China,for which we have known less about the genetic parameters and underlying candidate genes in relation to the body size traits.In this study,we obtained the genome-wide single nucleotide polymorphisms(SNPs)using the Illumina Bovine BeadChip in 275 Shuxuan cattle.These SNPs were first used for estimating genetic parameters for the withers height(WH)and diagonal body length(BL).Using the bivariate animal model,the estimates(±standard error)of heritabilities were 0.71±0.22 and 0.49±0.29 for BL,and their genetic correlation was 0.64±0.37.Second,the genome-wide association study(GWAS)was performed.However,these did not result into genome-wide significant SNPs for both WH and BL traits.According to a less stringent suggestive significance,some positional candidate genes were found,and some of them(such as FAM110B,TAS1R2,PAX3,and FHIT)were previously reported in literature to be associated with body size traits in cattle.In conclusion,we estimated the genetic parameters in Shuxuan cattle using genomic information for the first time,which are required for implementing the genomic selection programs in the future. 展开更多
关键词 HERITABILITY Genetic correlation Genomic evaluation Genome-wide association study(GWAS)
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Genome-wide and candidate gene association studies identify BnPAP17 as conferring the utilization of organic phosphorus in oilseed rape
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作者 Ping Xu Hao Li +6 位作者 Haiyuan Li Ge Zhao Shengjie Dai Xiaoyu Cui Zhenning Liu Lei Shi Xiaohua Wang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1134-1149,共16页
Phosphorus(P)is essential for living plants,and P deficiency is one of the key factors limiting the yield in rapeseed production worldwide.As the most important organ for plants,root morphology traits(RMTs)play a key ... Phosphorus(P)is essential for living plants,and P deficiency is one of the key factors limiting the yield in rapeseed production worldwide.As the most important organ for plants,root morphology traits(RMTs)play a key role in P absorption.To investigate the genetic variability of RMT under low P availability,we dissected the genetic structure of RMTs by genome-wide association studies(GWAS),linkage mapping and candidate gene association studies(CGAS).A total of 52 suggestive loci were associated with RMTs under P stress conditions in 405 oilseed rape accessions.The purple acid phosphatase gene BnPAP17 was found to control the lateral root number(LRN)and root dry weight(RDW)under low P stress.The expression of BnPAP17 was increased in shoot tissue in P-efficient cultivars compared to root tissue and P-inefficient cultivars in response to low P stress.Moreover,the haplotype of BnPAP17^(Hap3)was detected for the selective breeding of P efficiency in oilseed rape.Over-expression of the BnPAP17^(Hap3)could promote the shoot and root growth with enhanced tolerance to low P stress and organic phosphorus(Po)utilization in oilseed rape.Collectively,these findings increase our understanding of the mechanisms underlying BnPAP17-mediated low P stress tolerance in oilseed rape. 展开更多
关键词 genome-wide association studies(GWAS) root morphology traits(RMTs) organic phosphorus(Po) oilseed rape BnPAP17
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The Islamic Studies in China:Research in the Field of History
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作者 Alimtohte Shiho 《Cultural and Religious Studies》 2024年第6期329-337,共9页
A history of the Islamic studies in China,not only includes studies on world Islam,it also includes research on Islam and Muslims in China.Before the Reform and Opening Up,China did not achieve much in this field,sinc... A history of the Islamic studies in China,not only includes studies on world Islam,it also includes research on Islam and Muslims in China.Before the Reform and Opening Up,China did not achieve much in this field,since then,the research field of Islam and Muslim in China has been expanding and the results have been published,forming a new trend.In this field,scholars such as Jin Yijiu,Li Xinghua,Qin Huibin,Zhou Guoli,Sha Qiuzhen,Zhou Xiefan,Wu Yungui,and Yang Huaizhong have made the most outstanding achievements.Especially in the collation of reference books and historical materials,in the past 20 years,The Encyclopedia of the history of Islam,The Chinese Encyclopedia of Islam have emerged,and the Chinese and World Encyclopedia of Islamic Law and other important historical books have been published.This paper focuses on the field of historical research and divided into academic research history at home and abroad,which is discussed from several fields such as general history,special history,national history,and regional history. 展开更多
关键词 Islamic studies China the field of history Chinese Islam world Islam
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Exploration of Interdisciplinary Integration in Teaching Reform of Legal Studies and Auditing
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作者 Lili Hao 《Journal of Contemporary Educational Research》 2024年第9期69-76,共8页
This paper attempts to explore interdisciplinary integration from four aspects:the necessity of interdisciplinary integration between legal studies and auditing,the difficulties and challenges encountered in this inte... This paper attempts to explore interdisciplinary integration from four aspects:the necessity of interdisciplinary integration between legal studies and auditing,the difficulties and challenges encountered in this integration,the ideas for teaching reform in the context of interdisciplinary integration,and the expected outcomes.The aim is to achieve an organic integration of legal studies and auditing through systematic teaching reforms,thereby providing students with comprehensive and integrated knowledge and skills training,ensuring the quality of talent cultivation,and adapting to the needs of social development. 展开更多
关键词 INTERDISCIPLINARY Legal studies AUDITING Teaching reform
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Longitudinal Studies on Illness Perceptions in Cancer Patients: A Scoping Review
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作者 Yanfei Zhang Min Yang +1 位作者 Jie Yao Baohua Cao 《Journal of Clinical and Nursing Research》 2024年第8期37-45,共9页
Objective:To conduct a scoping review of longitudinal studies related to disease perception in cancer patients and to provide a reference for the improvement of disease perception in cancer patients.Methods:Using the ... Objective:To conduct a scoping review of longitudinal studies related to disease perception in cancer patients and to provide a reference for the improvement of disease perception in cancer patients.Methods:Using the scoping method,PubMed,Web of Science,The Cochrane Library,Medline,CNKI,Wanfang Database,VIP Chinese Scientific and Technical Journals Database,and China Biomedical Literature Database were searched up to July 2023 for analysis and discussion of the included literature.Results:A total of 19 articles were included,distributed across 9 countries including China,the Netherlands,and the United Kingdom,with 8 articles published in China.The study subjects included patients with breast cancer,colorectal cancer,laryngeal cancer,lung cancer,esophageal cancer,and bladder cancer.The content covered dynamic changes in disease perception,the impact of disease perception,and the influencing factors of disease perception.Conclusion:The number of longitudinal studies on disease perception in cancer patients is gradually increasing and becoming more diverse.However,issues such as a small total number of studies,single research methods,and short observation periods persist.In the future,it is necessary to conduct in-depth longitudinal research on disease perception in cancer patients,expand the scope of research fields,and provide more comprehensive theories to guide clinical treatment and nursing practices,ultimately improving the treatment outcomes and quality of life for cancer patients. 展开更多
关键词 Illness perception CANCER Longitudinal studies Scoping review
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In Vivo Studies and Flow Cytometric Investigation on Anticancer Potential of Selenium Nanoparticles Synthesized via Aqueous Extract of Clerodendron phlomidis
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作者 Veeramani Subha Kirubanandan Shanmugam Renganathan Sahadevan 《Proceedings of Anticancer Research》 2024年第1期71-81,共11页
Nowadays,doctors and nutritionists recommend individuals incorporate selenium-rich foods such as nuts,cereals,and mushrooms into their regular diet to maintain fitness and overall health.Selenium nanoparticles(SeNPs)e... Nowadays,doctors and nutritionists recommend individuals incorporate selenium-rich foods such as nuts,cereals,and mushrooms into their regular diet to maintain fitness and overall health.Selenium nanoparticles(SeNPs)exhibit strong chemopreventive capabilities.The anticipations for SeNPs with enhanced and tunable bioactive activities have led to a keen interest in phytofabrication.In this study,the aqueous extract of Clerodendron phlomidis plant leaves was utilized for the synthesis of SeNPs.In traditional Indian medicine,this plant extract is recognized as a significant anti-diabetic agent.The flavonoids tetrahydroxylflavone,7-hydroxyflavanone,and 6,4’-dimethyl-7-acetoxy-scutellarein present in this plant leaf extract demonstrate excellent anticancer activity.These secondary metabolites exhibit the ability to reduce sodium selenite into SeNPs.At a concentration of 13μg/mL,the synthesized SeNPs effectively inhibited the proliferation of the HepG2 cell line.The results suggest that the SeNPs possess promising anti-cancer potential against liver cancer and can be considered as a therapeutic agent for liver cancer treatment.Additionally,the cell cycle arrest induced by SeNPs was further confirmed by the fluorescence-activated cell sorting(FACS)method,indicating that SeNPs could efficiently differentiate cancer cells from normal cells.Notably,it showed a significant improvement in diethylnitrosamine(DEN)-induced Swiss Wistar rat groups.This scientific investigation highlights the high anti-cancer potential of SeNPs,positioning them as a promising therapeutic agent for liver cancer treatment. 展开更多
关键词 Selenium nanoparticles Green synthesis Liver cancer Clerodendron phlomidis Flow cytometry In vivo studies
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Additive-multiplicative Hazards Model for Case-Cohort Studies with Multiple Disease Outcomes 被引量:2
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作者 Jun-e LIU Jie ZHOU 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2017年第1期183-192,共10页
Case-cohort design is an efficient and economical design to study risk factors for diseases with expensive measurements, especially when the disease rate is low. When several diseases are of interest, multiple case-co... Case-cohort design is an efficient and economical design to study risk factors for diseases with expensive measurements, especially when the disease rate is low. When several diseases are of interest, multiple case-cohort design studies may be conducted using the same subcohort. To study the association between risk factors and each disease occurrence or death, we consider a general additive-multiplicative hazards model for case-cohort designs with multiple disease outcomes. We present an estimation procedure for the regression parameters of the additive-multiplicative hazards model, and show that the proposed estimator is consistent and asymptotically normal. Large sample approximation works well in finite sample studies in simulation. Finally, we apply the proposed method to a real data example for illustration. 展开更多
关键词 case-cohort studies additive-multiplicative model marginal hazards model multiple disease out-comes
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A Class of Weighted Estimators for Additive Hazards Model in Case-cohort Studies 被引量:3
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作者 Cai-lin DONG Jie ZHOU Liu-quan SUN 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2014年第4期1153-1168,共16页
Case-cohort sampling is a commonly used and efficient method for studying large cohorts. In many situations, some covariates are easily measured on all cohort subjects, and surrogate measurements of the expensive cova... Case-cohort sampling is a commonly used and efficient method for studying large cohorts. In many situations, some covariates are easily measured on all cohort subjects, and surrogate measurements of the expensive covariates also may be observed. In this paper, to make full use of the covariate data collected outside the case-cohort sample, we propose'a class of weighted estimators with general time-varying weights for the additive hazards model, and the estimators are shown to be consistent and asymptotically normal. We also identify the estimator within this class that maximizes efficiency, and simulation studies show that the efficiency gains of the proposed estimator over the existing ones can be substantial in practical situations. A real example is provided. 展开更多
关键词 additive hazards case-cohort study stratified sampling survival data two-phase design
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“Blind men and an elephant”:The need for animals in research,drug safety studies,and understanding civilizational diseases 被引量:1
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作者 Savani Anbalagan 《Animal Models and Experimental Medicine》 CAS CSCD 2023年第6期627-633,共7页
Animal-based research and drug safety studies are essential to understanding the mysteries of nature and the long-term survival of humans.Due to the rapid increase in the global human population,conflict-and economica... Animal-based research and drug safety studies are essential to understanding the mysteries of nature and the long-term survival of humans.Due to the rapid increase in the global human population,conflict-and economically driven human migration,tourism-related activities,densely populated metropolitan areas,and local policies,humans will be affected by a multitude of novel disease-causing microorganisms and civilizational diseases.Despite disparities among countries,recent and planned changes in regulations concerning animal research and drug safety studies could have detrimental effects on both the animal research community and nations lacking sufficient social support systems.Based on existing scientific literature,I argue that we need animal research encompassing aspects such as animal development,behavior,drug safety studies,and for the understanding of future civilizational diseases.Depending on the nature of the research questions and local challenges,a suitable animal model organism should be made mandatory. 展开更多
关键词 animal model drug safety studies RESEARCH ZEBRAFISH
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More Efficient Estimators for Marginal Additive Hazards Model in Case-cohort Studies with Multiple Outcomes 被引量:1
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作者 Jin WANG Jie ZHOU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2016年第3期351-362,共12页
Case-cohort study designs are widely used to reduce the cost of large cohort studies. When several diseases are of interest, we can use the same subcohort. In this paper, we will study the casecohort design of margina... Case-cohort study designs are widely used to reduce the cost of large cohort studies. When several diseases are of interest, we can use the same subcohort. In this paper, we will study the casecohort design of marginal additive hazards model for multiple outcomes by a more efficient version. Instead of analyzing each disease separately, ignoring the additional exposure measurements collected on subjects with other diseases, we propose a new weighted estimating equation approach to improve the efficiency by utilizing as much information collected as possible. The consistency and asymptotic normality of the resulting estimator are established. Simulation studies are conducted to examine the finite sample performance of the proposed estimator, which confirm the efficiency gains. 展开更多
关键词 case-cohort study multivariate failure times marginal additive hazards model efficient estimator
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Genome-wide association studies reveal the genetic basis of amino acid content variation in tea plants 被引量:1
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作者 GUO Ya-fei LI Dai-li +4 位作者 QIU Hai-ji ZHANG Xiao-liang LIU Lin ZHAO Jing-jing JIANG De-yuan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第11期3364-3379,共16页
Tea is one of the most popular non-alcoholic beverages in the world,and free amino acids,especially theanine,make a major contribution to the umami taste of tea.However,the genetic basis of the variation in amino acid... Tea is one of the most popular non-alcoholic beverages in the world,and free amino acids,especially theanine,make a major contribution to the umami taste of tea.However,the genetic basis of the variation in amino acid content in tea plants remains largely unknown.Here,we measured the free amino acid content in fresh leaves of 174 tea accessions over two years using a targeted metabolomics approach and obtained genotype data via RNA sequencing.Genome-wide association studies were conducted to investigate loci affecting the content of free amino acids.A total of 69 quantitative trait loci(–log10(P-value)>5)were identified.Functional annotation revealed that branched-chain amino acid aminotransferase,glutamine synthetase,nitrate transporter,and glutamate decarboxylase might be important for amino acid metabolism.Two significant loci,glutamine synthetase(Glu1,P=3.71×10^(−4);Arg1,P=4.61×10^(−5))and branched-chain amino acid aminotransferase(Val1,P=4.67×10^(−5);I_Leu1,P=3.56×10^(−6)),were identified,respectively.Based on the genotyping result,two alleles of CsGS(CsGS-L and CsGS-H)and CsBCAT(CsBCAT-L and CsBCAT-H)were selected to perform function verification.Overexpression of CsGS-L and CsGS-H enhanced the contents of glutamate and arginine in transgenic plants,and overexpression of CsBCAT-L and CsBCAT-H promoted the accumulation of valine,isoleucine and leucine.Enzyme activity assay uncovered that SNP1054 is important for CsGS catalyzing glutamate into glutamine.Furthermore,CsGS-L and CsGS-H differentially regulated the accumulation of glutamine,and CsBCAT-L and CsBCAT-H differentially regulated the accumulation of branched-chain amino acids.In summary,the findings in our study would provide new insights into the genetic basis of amino acids contents variation in tea plants and facilitate the identification of elite genes to enhance amino acids content. 展开更多
关键词 Camellia sinensis amino acids genetic variation association studies genotype analysis functional verification
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A review of challenges and opportunities in micropillar compression studies in Mg alloys 被引量:1
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作者 A.Kodam M.S.Gundi +3 位作者 Y.L.Chiu I.P.Jones S.S.Singh J.Jain 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第11期4043-4053,共11页
This review paper provides an overview of the micropillar compression technique as applied to magnesium(Mg) and its alloys. It explores the influence of various factors, such as pillar size, shape, temperature, and st... This review paper provides an overview of the micropillar compression technique as applied to magnesium(Mg) and its alloys. It explores the influence of various factors, such as pillar size, shape, temperature, and strain rate on the mechanical properties of Mg.Additionally, the impact of alloying elements, aging, and precipitates in Mg alloys has been extensively examined, revealing their significant influence on mechanical performance. The study highlights the strength and strain hardening improvements in Mg with decreasing pillar size in micropillar compression. Furthermore, the role of precipitates as strengthening agents, affecting deformation mechanisms and overall mechanical response, is explored. These valuable insights are crucial for designing Mg-based materials with enhanced mechanical properties for advanced engineering applications. 展开更多
关键词 A review of challenges and opportunities in micropillar compression studies in Mg alloys
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Roles of Case Studies and Case Reports in US East Asian Medicine:A Narrative-Medicine Perspective
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作者 Sarah E.Rivkin 《Chinese Medicine and Culture》 2023年第2期194-204,共11页
Recorded stories of the clinical encounter stretch back to ancient times.Throughout their history,these narratives have been called by different names,reflecting changes in format,function,and audience.This paper exam... Recorded stories of the clinical encounter stretch back to ancient times.Throughout their history,these narratives have been called by different names,reflecting changes in format,function,and audience.This paper examines and explains the differences in two related forms of clinical writing as practiced by East Asian Medicine clinicians in the United States today-the case study and the case report.Each has its strengths and weaknesses;each is suited to different roles.The case study is ideal for education and the practice of narrative medicine,whereas the case report has played a vital role in propelling East Asian Medicine into the arena of modern scientific research. 展开更多
关键词 Case record Case report Case study Herbal medicine Narrative medicine
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