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Ultrastructure and key identification points of fossilized Os Draconis in traditional Chinese medicine
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作者 Dong-Han Bai Zi Xing +5 位作者 Zi-Hao Zhang Zhi-Jie Zhang Da-Jun Lu Nan-Xi Huang Qiao-Chu Wang Lu Luo 《Traditional Medicine Research》 2026年第1期39-46,共8页
Background:The medicinal material known as Os Draconis(Longgu)originates from fossilized remains of ancient mammals and is widely used in treating emotional and mental conditions.However,fossil resources are nonrenewa... Background:The medicinal material known as Os Draconis(Longgu)originates from fossilized remains of ancient mammals and is widely used in treating emotional and mental conditions.However,fossil resources are nonrenewable,and clinical demand is increasingly difficult to meet,leading to a proliferation of counterfeit products.During prolonged geological burial,static pressure from the surrounding strata severely compromises the microstructural integrity of osteons in Os Draconis,but Os Draconis still largely retains the structural features of mammalian bone.Methods:Using verified authentic Os Draconis samples over 10,000 years old as a baseline,this study summarizes the ultrastructural characteristics of genuine Os Draconis.Employing electron probe microanalysis and optical polarized light microscopy,we examined 28 batches of authentic Os Draconis and 31 batches of counterfeits to identify their ultrastructural differences.Key points for ultrastructural identification of Os Draconis were compiled,and a new identification approach was proposed based on these differences.Results:Authentic Os Draconis exhibited distinct ultrastructural markers:irregularly shaped osteons with traversing fissures,deformed/displaced Haversian canals,and secondary mineral infill(predominantly calcium carbonate).Counterfeits showed regular osteon arrangements,absent traversal fissures,and homogeneous hydroxyapatite composition.Lab-simulated samples lacked structural degradation features.EPMA confirmed calcium carbonate infill in fossilized Haversian canals,while elemental profiles differentiated lacunae types(void vs.mineral-packed).Conclusion:The study established ultrastructural criteria for authentic Os Draconis identification:osteon deformation,geological fissures penetrating bone units,and heterogenous mineral deposition.These features,unattainable in counterfeits or modern processed bones,provide a cost-effective,accurate identification method.This approach bridges gaps in TCM material standardization and supports quality control for clinical applications. 展开更多
关键词 Os Draconis ULTRASTRUCTURE identification points electron probe polarized light microscope
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Synaptic pruning mechanisms and application of emerging imaging techniques in neurological disorders
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作者 Yakang Xing Yi Mo +1 位作者 Qihui Chen Xiao Li 《Neural Regeneration Research》 2026年第5期1698-1714,共17页
Synaptic pruning is a crucial process in synaptic refinement,eliminating unstable synaptic connections in neural circuits.This process is triggered and regulated primarily by spontaneous neural activity and experience... Synaptic pruning is a crucial process in synaptic refinement,eliminating unstable synaptic connections in neural circuits.This process is triggered and regulated primarily by spontaneous neural activity and experience-dependent mechanisms.The pruning process involves multiple molecular signals and a series of regulatory activities governing the“eat me”and“don't eat me”states.Under physiological conditions,the interaction between glial cells and neurons results in the clearance of unnecessary synapses,maintaining normal neural circuit functionality via synaptic pruning.Alterations in genetic and environmental factors can lead to imbalanced synaptic pruning,thus promoting the occurrence and development of autism spectrum disorder,schizophrenia,Alzheimer's disease,and other neurological disorders.In this review,we investigated the molecular mechanisms responsible for synaptic pruning during neural development.We focus on how synaptic pruning can regulate neural circuits and its association with neurological disorders.Furthermore,we discuss the application of emerging optical and imaging technologies to observe synaptic structure and function,as well as their potential for clinical translation.Our aim was to enhance our understanding of synaptic pruning during neural development,including the molecular basis underlying the regulation of synaptic function and the dynamic changes in synaptic density,and to investigate the potential role of these mechanisms in the pathophysiology of neurological diseases,thus providing a theoretical foundation for the treatment of neurological disorders. 展开更多
关键词 CHEMOKINE COMPLEMENT experience-dependent driven synaptic pruning imaging techniques NEUROGLIA signaling pathways synapse elimination synaptic pruning
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Conservation agriculture for sustainable food system:Current insights and emerging perspectives
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作者 Subhashisa PRAHARAJ Bharat LAL +3 位作者 Himansu Sekhar GOUDA Amit Kumar PANDEY Shivasankar ACHARYA Arunima KUMARI 《Regional Sustainability》 2025年第5期117-132,共16页
Global challenges,including resource inefficiency,rising food demand,sustainability concerns,and climate change,necessitate more efficient and resilient agricultural systems.Conservation agriculture(CA),which is based... Global challenges,including resource inefficiency,rising food demand,sustainability concerns,and climate change,necessitate more efficient and resilient agricultural systems.Conservation agriculture(CA),which is based on the principles of the minimum mechanical soil disturbance,permanent soil organic cover,and species diversification,provides a promising solution.This study examined the principles and mechanisms of CA,assessed its benefits and constraints,and identified key research gaps.This study focused on CA outcomes related to soil health,biodiversity,productivity,and ecosystem services,considering factors such as climate,soil type,and management practices.CA has demonstrated the potential to improve soil health,enhance biodiversity,and boost productivity across diverse regions.However,its effectiveness has been found to vary across studies,emphasizing the need for a more critical understanding of its benefits and limitations.Moreover,variations in outcomes are evident due to differences in experimental methodologies,environmental conditions,and socioeconomic factors.For the widespread adoption of CA practices,it is necessary to make personalized adjustments to it,integrating the corresponding technologies,thereby meeting the needs of farmers.Interdisciplinary research is crucial to refining CA practices and addressing existing knowledge gaps.This study is practiced to enhance the understanding of the potential of CA to promote a sustainable global food production system. 展开更多
关键词 CONSERVATION agriculture(CA) Minimum mechanical soil disturbance Permanent soil organic cover Species diversification Diversified crop ROTATION Crop residues Cover crops
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Large language models and large concept models in radiology:Present challenges,future directions,and critical perspectives
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作者 Suleman A Merchant Neesha Merchant +1 位作者 Shaju L Varghese Mohd Javed S Shaikh 《World Journal of Radiology》 2025年第11期1-38,共38页
Large language models(LLMs)have emerged as transformative tools in radiology artificial intelligence(AI),offering significant capabilities in areas such as image report generation,clinical decision support,and workflo... Large language models(LLMs)have emerged as transformative tools in radiology artificial intelligence(AI),offering significant capabilities in areas such as image report generation,clinical decision support,and workflow optimization.The first part of this manuscript presents a comprehensive overview of the current state of LLM applications in radiology,including their historical evolution,technical foundations,and practical uses.Despite notable advances,inherent architectural constraints,such as token-level sequential processing,limit their ability to perform deep abstract reasoning and holistic contextual understanding,which are critical for fine-grained diagnostic interpretation.We provide a critical perspective on current LLMs and discuss key challenges,including model reliability,bias,and explainability,highlighting the pressing need for novel approaches to advance radiology AI.Large concept models(LCMs)represent a nascent and promising paradigm in radiology AI,designed to transcend the limitations of token-level processing by utilizing higher-order conceptual representations and multimodal data integration.The second part of this manuscript introduces the foundational principles and theoretical framework of LCMs,highlighting their potential to facilitate enhanced semantic reasoning,long-range context synthesis,and improved clinical decision-making.Critically,the core of this section is the proposal of a novel theoretical framework for LCMs,formalized and extended from our group’s foundational concept-based models-the world’s earliest articulation of this paradigm for medical AI.This conceptual shift has since been externally validated and propelled by the recent publication of the LCM architectural proposal by Meta AI,providing a large-scale engineering blueprint for the future development of this technology.We also outline future research directions and the transformative implications of this emerging AI paradigm for radiologic practice,aiming to provide a blueprint for advancing toward human-like conceptual understanding in AI.While challenges persist,we are at the very beginning of a new era,and it is not unreasonable to hope that future advancements will overcome these hurdles,pushing the boundaries of AI in Radiology,far beyond even the most state-of-the-art models of today. 展开更多
关键词 Radiology artificial intelligence Large language models Large concept models Medical imaging artificial intelligence Artificial intelligence in healthcare Multimodal artificial intelligence models Explainable artificial intelligence Artificial intelligence model limitations and challenges Natural language processing in radiology Conceptual reasoning in artificial intelligence
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Contrast enhanced multi-detector CT and MR findings of a well-differentiated pancreatic vipoma 被引量:1
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作者 Luigi Camera Rosa Severino +5 位作者 Antongiulio Faggiano Stefania Masone Gelsomina Mansueto Simone Maurea Rosa Fonti Marco Salvatore 《World Journal of Radiology》 CAS 2014年第10期840-845,共6页
Pancreatic vipoma is an extremely rare tumor accounting for less than 2% of endocrine pancreatic neoplasms with a reported incidence of 0.1-0.6 per million. While cross-sectional imaging findings are usually not speci... Pancreatic vipoma is an extremely rare tumor accounting for less than 2% of endocrine pancreatic neoplasms with a reported incidence of 0.1-0.6 per million. While cross-sectional imaging findings are usually not specific, exact localization of the tumor by means of either computed tomography(CT) or magnetic resonance(MR) is pivotal for surgical planning. However, cross-sectional imaging findings are usually not specific and further characterization of the tumor may only be achieved bysomatostatin-receptor scintigraphy(SRS). We report the case of a 70 years old female with a two years history of watery diarrhoea who was found to have a solid, inhomogeneously enhancing lesion at the level of the pancreatic tail at Gadolinium-enhanced MR(Somatom Trio 3T, Siemens, Germany). The tumor had been prospectively overlooked at a contrast-enhanced multi-detector CT(Aquilion 64, Toshiba, Japan) performed after i.v. bolus injection of only 100 cc of iodinated non ionic contrast media because of a chronic renal failure(3.4 mg/mL) but it was subsequently confirmed by SRS. The patient first underwent a successful symptomatic treatment with somatostatin analogues and was then submitted to a distal pancreasectomy with splenectomy to remove a capsulated whitish tumor which turned out to be a well-differentiated vipoma at histological and immuno-histochemical analysis. 展开更多
关键词 PANCREATIC endocrine tumor Vasoactive intestinal peptide Multi-detector computed tomography CONTRAST induced nephropathy Magnetic resonance imaging Nephrogenic systemic fibrosis SOMATOSTATIN receptor SCINTIGRAPHY
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Structure and property evolution of atomically precise palladium clusters
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作者 Chang-Qing Meng Wan-Yu Cheng +6 位作者 Hao Yan Hui-Xin Xiang Chen-Hao Ruan Yue Zhao Cong-Qiao Xu Jun Li Chuan-Hao Yao 《Rare Metals》 2025年第4期2822-2829,共8页
Atomically precise palladium(Pd)clusters are emerging as versatile nanomaterials with applications in catalysis and biomedicine.This study explores the synthesis,structure evolution,and catalytic properties of Pd clus... Atomically precise palladium(Pd)clusters are emerging as versatile nanomaterials with applications in catalysis and biomedicine.This study explores the synthesis,structure evolution,and catalytic properties of Pd clusters stabilized by cyclohexanethiol(HSC_(6)H_(11))ligands.Using electrospray ionization mass spectrometry(ESI-MS)and single-crystal X-ray diffraction(SXRD),structures of the Pd clusters ranging from Pd4(SC_(6)H_(11))8 to Pd18(SC_(6)H_(11))36 were determined.This analysis revealed a structure evolution from polygonal to elliptical geometries of the PdnS2n frameworks as the cluster size increased.UV-Vis-NIR spectroscopy,combined with quantum chemical calculations,elucidated changes in the electronic structure of the clusters.Catalytic studies on the Sonogashira cross-coupling reactions demonstrated a size-dependent decline in activity attributed to variations in structural arrangements and electronic properties.Mechanistic insights proposed a distinctive Pd(Ⅱ)-Pd(Ⅳ)catalytic cycle.This research underscores how ligands and cluster size influence the structures and properties of Pd clusters,offering valuable insights for the future design and application of Pd clusters in advanced catalysis and beyond. 展开更多
关键词 structure evolution catalytic properties quantum chemical calculations cyclohexanethiol ligands electrospray ionization mass spectrometry esi ms atomically precise palladium clusters sonogashira cross coupling reactions electronic structure
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Dynamic development of microglia and macrophages after spinal cord injury 被引量:1
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作者 Hu-Yao Zhou Xia Wang +5 位作者 Yi Li Duan Wang Xuan-Zi Zhou Nong Xiao Guo-Xing Li Gang Li 《Neural Regeneration Research》 2025年第12期3606-3619,共14页
Secondary injury following spinal cord injury is primarily characterized by a complex inflammatory response,with resident microglia and infiltrating macrophages playing pivotal roles.While previous studies have groupe... Secondary injury following spinal cord injury is primarily characterized by a complex inflammatory response,with resident microglia and infiltrating macrophages playing pivotal roles.While previous studies have grouped these two cell types together based on similarities in structure and function,an increasing number of studies have demonstrated that microglia and macrophages exhibit differences in structure and function and have different effects on disease processes.In this study,we used single-cell RNA sequencing and spatial transcriptomics to identify the distinct evolutionary paths of microglia and macrophages following spinal cord injury.Our results showed that microglia were activated to a pro-inflammatory phenotype immediately after spinal cord injury,gradually transforming to an anti-inflammatory steady state phenotype as the disease progressed.Regarding macrophages,our findings highlighted abundant communication with other cells,including fibroblasts and neurons.Both pro-inflammatory and neuroprotective effects of macrophages were also identified;the pro-inflammatory effect may be related to integrin β2(Itgb2) and the neuroprotective effect may be related to the oncostatin M pathway.These findings were validated by in vivo experiments.This research underscores differences in the cellular dynamics of microglia and macrophages following spinal cord injury,and may offer new perspectives on inflammatory mechanisms and potential therapeutic targets. 展开更多
关键词 acute inflammation bioinformatics analysis FIBROBLAST integrinβ2 ligand-receptor interaction NEUROINFLAMMATION oncostatin M single-cell RNA sequencing spatial transcriptomics spinal cord injury
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Numerical Analysis and Geometric Assessment of Air Layer Distribution in a Ventilated Planing Hull in Calm Water
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作者 Massimiliano Chillemi Filippo Cucinotta Felice Sfravara 《哈尔滨工程大学学报(英文版)》 2026年第1期46-62,共17页
The issue of resistance reduction through hull ventilation is of particular interest in contemporary research.This paper presents multiphase computational fluid dynamics(CFD)simulations with 2-DOF motion of a planing ... The issue of resistance reduction through hull ventilation is of particular interest in contemporary research.This paper presents multiphase computational fluid dynamics(CFD)simulations with 2-DOF motion of a planing hull.The original hull was modified by introducing a step to allow air ventilation.Following an assessment of the hull performance,a simulation campaign in calm water was conducted to characterize the hull at various forward speeds and air insufflation rates for a defined single step geometry.Geometric analysis of the air layer thickness beneath the hull for each simulated condition was performed using a novel method for visualizing local air thickness.Additionally,two new parameters were introduced to understand the influence of spray rails on the air volume beneath the hull and to indicate the primary direction of ventilated air escape.A validation campaign and an assessment of uncertainty of the simulation has been conducted.The features offered by the CFD methodology include the evaluation of the air layer thickness as a function of hull velocity and injection flow rate and the air volume distribution beneath the hull.The air injection velocity can be adjusted across various operating conditions,thereby preventing performance or efficiency loss during navigation.Based on these findings,the study highlights the benefits of air insufflation in reducing hull resistance for high-speed planing vessels.This work lays a robust foundation for future research and new promising topics,as the exploration of air insufflation continues to be a topic of contemporary interest within naval architecture and hydrodynamics. 展开更多
关键词 Computational fluid dynamics Air cavity ships Planing hull HYDRODYNAMICS Maritime sustainability
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Quality evaluation and chemical profiling of Cyperi Rhizoma(Xiangfu)using traditional quality assessment,GC-MS,RP-HPLC,and FTIR techniques
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作者 Lu Luo Dong-Han Bai +7 位作者 Shu-Min Chen Da-Jun Lu Nan-Xi Huang Qiao-Chu Wang Jun-Na Yao Lu Jia Zhi-Jie Zhang Rao-Rao Li 《Traditional Medicine Research》 2026年第2期20-29,共10页
Background:Cyperi Rhizoma,derived from Cyperus rotundus L.,is a widely used medicinal herb in traditional Chinese medicine(TCM),with Shandong Province recognized as its geo-authentic habitat.However,the quality of Cyp... Background:Cyperi Rhizoma,derived from Cyperus rotundus L.,is a widely used medicinal herb in traditional Chinese medicine(TCM),with Shandong Province recognized as its geo-authentic habitat.However,the quality of Cyperi Rhizoma varies significantly across different regions,potentially influencing its therapeutic efficacy.This study investigates the influence of geographic origin on the chemical composition and overall quality of Cyperi Rhizoma.Methods:A comprehensive approach,including traditional quality assessment,GC-MS(g as c hromatography-m ass s pectrometry),RP-HPLC(r everse p hase h igh-p erformance l iquid c hromatography),and FT-IR(f ourier t ransform i nfrared s pectroscopy)techniques,was employed to analyze Cyperi Rhizoma samples from Shandong Province.These methods examined the physical appearance,chemical profile,and content variations,particularly focusing onα-cyperone.Results:Traditional quality assessments revealed noticeable differences in the external characteristics of the samples.GC-MS analysis identified a variety of unique chemical constituents,while RP-HPLC and FT-IR showed significant variations inα-cyperone content,with higher levels found in Shandong samples.Conclusion:These results demonstrate that geographic origin is a critical determinant of Cyperi Rhizoma quality,with Shandong specimens exhibiting superiorα-cyperone levels and characteristic phytochemical profiles.This validates the geo-authenticity concept in TCM and provides actionable data for developing evidence-based quality standards,suggesting that provenance should be prioritized in medicinal material selection and pharmacopeial specifications. 展开更多
关键词 Cyperi Rhizoma traditional Chinese medicine GC-MS FTIR quality
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Stem cell therapy in inflammatory bowel disease: A promising therapeutic strategy? 被引量:8
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作者 Ana I Flores Gonzalo J Gómez-Gómez +1 位作者 ángeles Masedo-González M Pilar Martínez-Montiel 《World Journal of Stem Cells》 SCIE CAS 2015年第2期343-351,共9页
Inflammatory bowel diseases are inflammatory, chronic and progressive diseases of the intestinal tract for which no curative treatment is available. Research in other fields with stem cells of different sources and wi... Inflammatory bowel diseases are inflammatory, chronic and progressive diseases of the intestinal tract for which no curative treatment is available. Research in other fields with stem cells of different sources and with immunoregulatory cells(regulatory T-lymphocytes and dendritic T-cells) opens up new expectations for their use in these diseases. The goal for stem cell-based therapy is to provide a permanent cure. To achieve this, it will be necessary to obtain a cellular product, original or genetically modified, that has a high migration capacity and homes into the intestine, has high survival after transplantation, regulates the immune reaction while not being visible to the patient's immune system, and repairs the injured tissue. 展开更多
关键词 Mesenchymal STEM CELL Hematopoieticstem CELL Inflammatory bowel DISEASE Crohn's DISEASE ULCERATIVE colitis Amniotic fluid STEM CELLS Inducedpluripotent STEM CELLS Intestinal STEM CELLS Endothelialprogenitor CELLS Tolerogenic immune CELL therapies
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Optimizing stem cells for cardiac repair:Current status and new frontiers in regenerative cardiology 被引量:6
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作者 Shant Der Sarkissian Thierry Lévesque Nicolas Noiseux 《World Journal of Stem Cells》 SCIE CAS 2017年第1期9-25,共17页
Cell therapy has the potential to improve healing of ischemic heart, repopulate injured myocardium and restore cardiac function. The tremendous hope and potential of stem cell therapy is well understood, yet recent tr... Cell therapy has the potential to improve healing of ischemic heart, repopulate injured myocardium and restore cardiac function. The tremendous hope and potential of stem cell therapy is well understood, yet recent trials involving cell therapy for cardiovascular diseases have yielded mixed results with inconsistent data thereby readdressing controversies and unresolved questions regarding stem cell efficacy for ischemic cardiac disease treatment. These controversies are believed to arise by the lack of uniformity of the clinical trial methodologies, uncertainty regarding the underlying reparative mechanisms of stem cells, questions concerning the most appropriate cell population to use, the proper delivery method and timing in relation to the moment of infarction, as well as the poor stem cell survival and engraftment especially in a diseased microenvironment which is collectively acknowledged as a major hindrance to any form of cell therapy. Indeed, the microenvironment of the failing heart exhibits pathological hypoxic, oxidative and inflammatory stressors impairing the survival of transplanted cells. Therefore, in order to observe any significant therapeutic benefit there is a need to increase resilience of stem cells to death in the transplant microenvironment while preserving or better yet improving their reparative functionality. Although stem cell differentiation into cardiomyocytes has been observed in some instance, the prevailing reparative benefits are afforded through paracrine mechanisms that promote angiogenesis, cell survival, transdifferentiate host cells and modulate immune responses. Therefore, to maximize their reparative functionality, ex vivo manipulation of stem cells through physical, genetic and pharmacological means have shown promise to enable cells to thrive in the postischemic transplant microenvironment. In the present work, we will overview the current status of stem cell therapy for ischemic heart disease, discuss the most recurring cell populations employed, the mechanisms by which stem cells deliver a therapeutic benefit andstrategies that have been used to optimize and increase survival and functionality of stem cells including ex vivo preconditioning with drugs and a novel "pharmacooptimizer" as well as genetic modifications. 展开更多
关键词 Stem cell REGENERATIVE medicine Cellular CARDIOMYOPLASTY Preconditioning Myocardial INFARCTION Heart failure Viability PARACRINE activity Transplantation Pharmaco-optimizer
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GSTM1,GSTT1,GSTP1 and CYP1A1 genetic polymorphisms and susceptibility to esophageal cancer in a French population:Different pattern of squamous cell carcinoma and adenocarcinoma 被引量:7
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作者 Ahmed Abbas Karine Delvinquière +4 位作者 Mathilde Lechevrel Pierre Lebailly Pascal Gauduchon Guy Launoy Fran ois Sichel 《World Journal of Gastroenterology》 SCIE CAS CSCD 2004年第23期3389-3393,共5页
AIM:To evaluate the association between CYP1A1 and GSTs genetic polymorphisms and susceptibility to esophageal squamous cell carcinoma(SCC)and esophageal adenocarcinoma(ADC)in a high risk area of northwest of France. ... AIM:To evaluate the association between CYP1A1 and GSTs genetic polymorphisms and susceptibility to esophageal squamous cell carcinoma(SCC)and esophageal adenocarcinoma(ADC)in a high risk area of northwest of France. METHODS:A case-control study was conducted to investigate the genetic polymorphisms of these enzymes (CYPIAI*2C and GSTP1 exon 7 Val alleles,GSTMI*2/*2 and GSTTl *2/*2 null genotypes).A total of 79 esophageal cancer cases and 130 controls were recruited. RESULTS:GSTMI*2/*2 and CYPIAI*IA/*2C genotype frequencies were higher among squamous cell carcinomas at a level dose to statistical significance(OR =1.83,95% CI 0.88-3.83,P=0.11;OR=3.03,95% CI 0.93-9.90,P=0.07, respectively).For GSTP1 polymorphism,no difference was found between controls and cases,whatever their histological status.Lower frequency of GSTT1 deletion was observed in ADC group compared to controls with a statistically significant difference(OR=13.31,95% CI 1.66-106.92,P<0.01). CONCLUSION:In SCC,our results are consistent with the strong association of this kind of tumour with tobacco exposure.In ADC,our results suggest 3 distinct hypotheses: (1)activation of exogenous procarcinogens,such as small halogenated compounds by GSTT1;(2)contribution of GSTT1 to the inflammatory response of esophageal mucosa,which is known to be a strong risk factor for ADC, possibly through leukotriene synthesis;(3)higher sensitivity to the inflammatory process associated with intracellular depletion of glutathione. 展开更多
关键词 ACYLTRANSFERASES ADENOCARCINOMA Adult Aged Aged 80 and over Carcinoma Squamous Cell Case-Control Studies Cytochrome P-450 CYP1A1 Esophageal Neoplasms Female France Genetic Predisposition to Disease Genotype Glutathione Transferase Humans Male Middle Aged Polymorphism Genetic Research Support Non-U.S. Gov't Risk Factors
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Structural stability, optical and dielectric properties of the (Ba_(1/5)Pb_(1/5)Sr_(1/5)RE_(1/5)K_(1/5))TiO_(3) high-entropy ceramic
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作者 C.Herbert-Galarza A.Durán 《International Journal of Minerals,Metallurgy and Materials》 2025年第11期2821-2834,共14页
A high-entropy matrix with highly polarizable elements sharing a rare-earth element at the same crystallographic site was designed using the chemical formula Ba_(1/5)Pb_(1/5)Sr_(1/5)RE_(1/5)K_(1/5)TiO_(3)(BPSREKTO),wh... A high-entropy matrix with highly polarizable elements sharing a rare-earth element at the same crystallographic site was designed using the chemical formula Ba_(1/5)Pb_(1/5)Sr_(1/5)RE_(1/5)K_(1/5)TiO_(3)(BPSREKTO),where rare-earth(RE)=La,Nb,Sm,Gd,Dy,Ho,Y,and Lu.Single-phase stability was observed only in the BPSREKTO with RE=La,Nd,and Sm high-entropy compounds.The crystal structure,optical properties,and ferroelectric nature of the single-phase ceramic compounds were investigated.Elemental and structural analyses revealed that all the cations were homogeneously distributed in a global centrosymmetric cubic structure(S.G.Pm3m).Optical absorption showed that the RE=Nd compound is more photoactive in the 200-1000 nm wavelength range,unlike the RE=La,Sm high-entropy compounds.The introduction of RE elements in high-entropy ceramic(HEC)systems affects the indirect bandgap of BPSREKTO with RE=La,Nd,and Sm.It was also found that cationic disorder increases the Urbach energy,leading to a decrease in the indirect energy bandgap in the HEC compound compared to the homologue BaTiO_(3)/SrTiO_(3) single-phase.The dielectric spectra show a broad peak in the dielectric constant and dielectric loss,which are shifted in temperatures with increasing frequencies due to a relaxor ferroelectric transition typical of the diffuse phase transitions.This relaxor behavior was unexpected,because the global crystal structure was centrosymmetric,implying an increase in the number of polar nanoregions(PNRs).These PNRs coexisting with non-polar regions(NPRs)were observed using piezo-force microscopy.Furthermore,the slim polarization loop confirmed the relaxor behavior of BPSREKTO with RE=La,Nd,and Sm.These ferroelectric features make these RE-modified HEC materials good candidates for high-energy storage applications. 展开更多
关键词 high-entropy ceramics perovskite compounds optical properties dielectric properties scanning electron microscopy relaxor ferroelectrics
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Recent advances in the biosynthesis of natural products from C1 compounds
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作者 Xinzhe Zhang Aipeng Li +1 位作者 Xiaohan Huang Qiang Fei 《Chinese Journal of Chemical Engineering》 2025年第7期277-285,共9页
One-carbon(C1)compounds,such as CO_(2),methane,and methanol,are emerging as promising feedstocks for next-generation biomanufacturing due to their abundance and low cost.In recent years,there has been growing interest... One-carbon(C1)compounds,such as CO_(2),methane,and methanol,are emerging as promising feedstocks for next-generation biomanufacturing due to their abundance and low cost.In recent years,there has been growing interest in harnessing microorganisms to convert these carbon sources into valuable natural products(NPs),which offers great potential for sustainable development.This review systematically outlines recent advancements in biocatalysts,synthetic biology,and process optimization aimed at improving the feasibility and scalability of producing C1-based NPs.Current challenges and insights into NPs biomanufacturing from C1 compounds are thoroughly examined in the areas of multi-gene editing,metabolic regulation,and synthetic microbial consortium.With ongoing progress in biosynthetic tools and fermentation techniques,C1-based biomanufacturing is becoming a versatile and sustainable platform for generating diverse value-added products. 展开更多
关键词 Synthetic biology One-carbon compounds Natural products BIOCATALYSIS Carbon neutralization BIOTECHNOLOGY
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Are there Class II rocks?
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作者 Ming Cai 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第12期7489-7502,共14页
This paper addresses a fundamental question in rock mechanics:Are there Class II rocks?The historical development of servo-controlled rock testing machines is reviewed,followed by a brief review of some stiff testing ... This paper addresses a fundamental question in rock mechanics:Are there Class II rocks?The historical development of servo-controlled rock testing machines is reviewed,followed by a brief review of some stiff testing machines.The pioneering work of some researchers is reviewed,and the misconception of classifying rocks into Class I and Class II is discussed.The mechanism of post-peak Class II behavior is discussed based on some recent test results.When a brittle hard rock is tested using a soft testing machine under axial-strain-controlled loading,violent failure can occur when the peak strength is reached,and the post-peak stress-strain curve cannot be obtained.However,a Class II post-peak stress-strain curve can be obtained when the rock is tested under lateral-strain-controlled loading.If a stiff testing machine is used,Class I and Class II post-peak stress-strain curves will be obtained under axial-and lateral-strain-controlled loadings,respectively.It is therefore not appropriate to classify rocks into Class I or Class II rocks.The influences of other conditions,such as rock type,confinement,and specimen height-to-diameter ratio,on the type(Class I or Class II)of post-peak stress-strain curves are also discussed.Finally,some misconceptions in the rock mechanics community,stemming from the concept of“Class II rock”,are discussed.By clarifying these concepts related to Class I and Class II behaviors,this paper seeks to clarify misunderstandings and misapplications related to post-peak strength and deformation properties in the field. 展开更多
关键词 Class I Class II Brittle hard rock Post-peak stress-strain curve Rock dilation Loading control mode
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Protonation-Induced Molecular Fragmentation to Improve Heavy Crude Quality:Comparative Laboratory-Field Study with RDV■
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作者 William J.Jimenez Carlos A.Rivera +1 位作者 Hernán O.Gonzalez Víctor Silva Q. 《Journal of Energy and Power Engineering》 2025年第4期141-149,共9页
Heavy crude oils present significant operational challenges due to their high viscosity and low API gravity.Conventional methods are often inefficient and lack scalability.This study evaluates the chemical technology ... Heavy crude oils present significant operational challenges due to their high viscosity and low API gravity.Conventional methods are often inefficient and lack scalability.This study evaluates the chemical technology known as RDV■(dynamic vasoactive reactor),a formulation characterized by threshold-based molecular reconfiguration,validated through field-proven catalytic behavior that induces molecular fragmentation of long-chain fractions(C_(17)+)into medium-chain fractions(C_(13)-C_(16))through protonation and carbocation formation.A field study in Texas was conducted on 160 barrels of heavy crude(19.6°API)treated with an ultra-low dose of 1,486 ppm of RDV■.Results obtained over a 157-day period under seasonal thermal variations showed an increase of+5.4°API,a reduction in water content to 0.1%,and complete elimination of the paraffin bed.Unlike conventional chemical treatments,RDV■operates at ultra-low concentrations and sustains its effect over extended periods without re-dosing,redefining operational paradigms in heavy crude processing.These findings validate the effectiveness of RDV■under uncontrolled field conditions and demonstrate a per-ppm efficiency 21.8 times higher than previously observed in laboratory studies.RDV■technology is established as a scalable and economically efficient solution for upgrading heavy crude oils.These results position RDV■as a transformative technology for sustainable energy operations,with direct implications for heavy crude upgrading strategies in industrial settings. 展开更多
关键词 RDV■technology heavy crude upgrading hydrocarbon protonation molecular fragmentation(C₁₇+) API gravity enhancement field-proven catalytic performance
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Construction of a New Clinical Teaching System for Non-Alcoholic Fatty Liver Disease(NAFLD)based on the Dynamic Training Model Integrating“Guidelines,Clinical Practice,and Scientific Research”
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作者 Suzhen Jiang Nan Wu 《Journal of Contemporary Educational Research》 2025年第3期143-148,共6页
With the shift in the definition of disease from non-alcoholic fatty liver disease(NAFLD)to metabolism-associated fatty liver disease(MAFLD),as well as the rapid evolution of pathological classification and therapeuti... With the shift in the definition of disease from non-alcoholic fatty liver disease(NAFLD)to metabolism-associated fatty liver disease(MAFLD),as well as the rapid evolution of pathological classification and therapeutic targets,traditional clinical teaching models face challenges such as outdated guideline updates,disjointed translation of scientific research,and limited skill training.This study proposes a dynamic training model integrating“guidelines,clinical practice,and scientific research.”Through stratified case-based teaching(e.g.,FibroScan simulator and metabolic sand table),dynamic guideline analysis(comparing old and new evidence),and the integration of scientific thinking(visualization of CAND1 protein mechanism),a teaching system that integrates theory and practice is constructed.Innovatively developed smart assistant tools(AI decision support system,VR liver biopsy simulator)and a multi-dimensional evaluation system(deviation analysis of diagnosis and treatment pathways,milestone assessment)are used while emphasizing metabolic medicine integration(continuous glucose monitoring and digital therapy)and ethical privacy protection(federated learning framework).This model aims to cultivate students’evidence-based decision-making skills and scientific research transformation thinking through dynamic knowledge base construction and interdisciplinary collaboration,providing sustainable teaching solutions to cope with the rapid iteration of NAFLD diagnosis and treatment. 展开更多
关键词 Non-alcoholic fatty liver disease(NAFLD) Trinity teaching model Metabolism-associated fatty liver disease(MAFLD) Clinical teaching reform Smart assistant tools Interdisciplinary integration Evidence-based medicine
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Improved SE-UNet network-based semantic segmentation and extraction of hidden geological significance in geological maps
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作者 Kai Ma Jun-jie Liu +5 位作者 Si-qi Lu Ze-hua Huang Miao Tian Jun-yuan Deng Zhong Xie Qin-jun Qiu 《China Geology》 2025年第4期643-660,共18页
Automatic segmentation and recognition of content and element information in color geological map are of great significance for researchers to analyze the distribution of mineral resources and predict disaster informa... Automatic segmentation and recognition of content and element information in color geological map are of great significance for researchers to analyze the distribution of mineral resources and predict disaster information.This article focuses on color planar raster geological map(geological maps include planar geological maps,columnar maps,and profiles).While existing deep learning approaches are often used to segment general images,their performance is limited due to complex elements,diverse regional features,and complicated backgrounds for color geological map in the domain of geoscience.To address the issue,a color geological map segmentation model is proposed that combines the Felz clustering algorithm and an improved SE-UNet deep learning network(named GeoMSeg).Firstly,a symmetrical encoder-decoder structure backbone network based on UNet is constructed,and the channel attention mechanism SENet has been incorporated to augment the network’s capacity for feature representation,enabling the model to purposefully extract map information.The SE-UNet network is employed for feature extraction from the geological map and obtain coarse segmentation results.Secondly,the Felz clustering algorithm is used for super pixel pre-segmentation of geological maps.The coarse segmentation results are refined and modified based on the super pixel pre-segmentation results to obtain the final segmentation results.This study applies GeoMSeg to the constructed dataset,and the experimental results show that the algorithm proposed in this paper has superior performance compared to other mainstream map segmentation models,with an accuracy of 91.89%and a MIoU of 71.91%. 展开更多
关键词 Geological map UNet model Image segmentation Semantic segmentation Pixel pre-segmentation Clustering algorithm Attention mechanism Deep learning Artificial intelligence Geological survey engineering
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Outcomes of a non-diffractive extended depth of focus intraocular lens in patients with well-controlled glaucoma and ocular hypertension
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作者 Jia-Ru Liu Andrei-Alexandru Szigiato Paul Harasymowycz 《International Journal of Ophthalmology(English edition)》 2025年第1期79-85,共7页
AIM:To assess visual outcomes and satisfaction of a non-diffractive extended depth of focus(EDOF)intraocular lens(IOL)in individuals with ocular hypertension(OHT)and well-controlled mild glaucoma undergoing cataract s... AIM:To assess visual outcomes and satisfaction of a non-diffractive extended depth of focus(EDOF)intraocular lens(IOL)in individuals with ocular hypertension(OHT)and well-controlled mild glaucoma undergoing cataract surgery.METHODS:An investigator-initiated,single-center,prospective,interventional,noncomparative study conducted in Montreal,Canada.The study enrolled 31 patients(55 eyes)with OHT or mild glaucoma who received a non-diffractive EDOF IOL(Acrysof IQ Vivity).Participants underwent sequential cataract surgery with the Vivity IOL.Follow-up evaluations occurred at 1d,1,and 3mo postoperatively,assessing uncorrected distance,intermediate,and near visual acuity.Questionnaires(QUVID:Questionnaire for visual disturbances and IOLSAT:Intraocular lens satisfaction)were administered pre and post-operatively to measure visual disturbances and spectacle independence in various lighting.Safety parameters included intraocular pressure(IOP),glaucoma medications,spherical equivalence,mean deviation and pattern standard deviation or square root of lost variance on Octopus visual field.RESULTS:At 1 and 3mo postoperatively,significant improvements were observed in uncorrected distance and intermediate visual acuity.Spectacle independence was enhanced for distance and intermediate vision,especially in bright light settings.Spectacle-free intermediate vision was improved even in dim lighting.Visual disturbances,particularly glare symptoms,were reduced,and there was a notable decrease in IOP and glaucoma medication burden at 3mo.There was more hazy vision postoperatively with no impact on visual acuity and visual satisfaction.CONCLUSION:The non-diffractive EDOF lens improves distance and intermediate spectacle-free visual function in patients with OHT and well-controlled glaucoma.The findings highlight significant improvements in visual acuity,reduced glare,enhanced spectacle independence,and improved visual performance in different lighting conditions. 展开更多
关键词 extended depth of focus refractive GLAUCOMA ocular hypertension CATARACT intraocular lens
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In vitro effect of amoxicillin and clarithromycin on the 3' region of cagA gene in Helicobacter pylori isolates 被引量:5
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作者 Javier Andrés Bustamante-Rengifo Andrés Januer Matta +1 位作者 Alvaro Pazos Luis Eduardo Bravo 《World Journal of Gastroenterology》 SCIE CAS 2013年第36期6044-6054,共11页
AIM:To evaluate the in vitro effect of amoxicillin and clarithromycin on the cag pathogenicity island(cag PAI).METHODS:One hundred and forty-nine clinical isolates of Helicobacter pylori(H.pylori)cultured from gastric... AIM:To evaluate the in vitro effect of amoxicillin and clarithromycin on the cag pathogenicity island(cag PAI).METHODS:One hundred and forty-nine clinical isolates of Helicobacter pylori(H.pylori)cultured from gastric biopsies from 206 Colombian patients with dyspeptic symptoms from a high-risk area for gastric cancer were included as study material.Antimicrobial susceptibility was determined by the agar dilution method.Resistant isolates at baseline and in amoxicillin and clarithromycin serial dilutions were subjected to genotyping(cagA,vacA alleles s and m),Glu-Pro-Ile-Tyr-Ala(EPIYA)polymerase chain reaction and random amplified polymorphic DNA(RAPD).Images of the RAPD amplicons were analyzed by Gel-Pro Analyzer 4.5program.Cluster analyses was done using SPSS 15.0statistical package,where each of the fingerprint bands were denoted as variables.Dendrograms were designed by following Ward’s clustering method and the estimation of distances between each pair of H.pylori isolates was calculated with the squared Euclidean distance.RESULTS:Resistance rates were 4%for amoxicillin and 2.7%for clarithromycin with 2%double resistances.Genotyping evidenced a high prevalence of the genotype cagA-positive/vacA s1m1.The 3’region of cagA gene was successfully amplified in 92.3%(12/13)of the baseline resistant isolates and in 60%(36/60)of the resistant isolates growing in antibiotic dilutions.Upon observing the distribution of the number of EPIYA repetitions in each dilution with respect to baseline isolates,it was found that in 61.5%(8/13)of the baseline isolates,a change in the number of EPIYA repetitions lowered antibiotic pressure.The gain and loss of EPIYA motifs resulted in a diversity of H.pylori subclones after bacterial adjustment to changing conditions product of antibiotic pressure.RAPD PCR evidenced the close clonal relationship between baseline isolates and isolates growing in antibiotic dilutions.CONCLUSION:Antibiotic pressure does not induce loss of the cag pathogenicity island,but it can leadin most cases-to genetic rearrangements within the3’region cagA of the founding bacteria that can affect the level of tyrosine phosphorylation impacting on its cellular effects and lead to divergence of cagA-positive subclones. 展开更多
关键词 HELICOBACTER PYLORI Antimicrobial susceptibility cag pathogenicity island CAGA 3’region Random amplified POLYMORPHIC DNA-polymerase chain reaction
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