检索结果-南通市图书馆

Role of vitamin B_(12) on methylmalonyl-CoA mutase activity

Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第6期13卷 423-437页

作者： Tóshiko TAKAHASHI-IIGUEZ Enrique GARCíA-HERNANDEZ Roberto ARREGUíN-ESPINOSA María Elena flores Department of Molecular Biology and Biotechnology Institute of Biomedical ResearchNational Autonomous University of MexicoD.F.04510Mexico Department of Chemistry of Biomacromolecules Institute of ChemistryNational Autonomous University of MexicoD.F.04510Mexico

Vitamin B 12 is an organometallic compound with important metabolic derivatives that act as cofactors of certain enzymes,which have been grouped into three subfamilies depending on their *** them,methylmalonyl-CoA mutase (MCM) has been extensively *** enzyme catalyzes the reversible isomerization of L-methylmalonyl-CoA to succinyl-CoA using adenosylcobalamin (AdoCbl) as a cofactor participating in the generation of radicals that allow isomerization of the *** crystal structure of MCM determined in Propionibacterium freudenreichii *** has helped to elucidate the role of this cofactor AdoCbl in the reaction to specify the mechanism by which radicals are generated from the coenzyme and to clarify the interactions between the enzyme,coenzyme,and *** existence of human methylmalonic acidemia (MMA) due to the presence of mutations in MCM shows the importance of its role in *** recent crystallization of the human MCM has shown that despite being similar to the bacterial protein,there are significant differences in the structural organization of the two *** studies have identified the involvement of an accessory protein called MMAA,which interacts with MCM to prevent MCM's inactivation or acts as a chaperone to promote regeneration of inactivated *** interdisciplinary studies using this protein as a model in different organisms have helped to elucidate the mechanism of action of this isomerase,the impact of mutations at a functional level and their repercussion in the development and progression of MMA in *** is still necessary to study the mechanisms involved in more detail using new methods.

关键词： Vitamin B 12 Methylmalonyl-CoA mutase (MCM) MMAA MeaB Methylmalonic academia (MMA) Protectase Reactivase

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

road to stemness in hepatocellular carcinoma

引用

World Journal of Gastroenterology 2017年第37期23卷 6750-6776页

作者： Teresita NJ flores-Téllez Saúl Villa-Trevino Carolina Pina-Vázquez Departam ento de Biología Celular Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional(CINVESTAV-IPN) Av.IPN No.2508 Col

Carcinogenic process has been proposed to relay on the capacity to induce local tissue damage and proliferative repair. Liver has a great regeneration capacity and currently, most studies point towards the dominant role of hepatocytes in regeneration at all levels of liver damage. The most frequent liver cancer is hepatocellular carcinoma(HCC). Historical findings originally led to the idea that the cell of origin of HCC might be a progenitor cell. However, current linage tracing studies put the progenitor hypothesis of HCC origin into question. In agreement with their dominant role in liver regeneration, mature hepatocytes are emerging as the cell of origin of HCC, although, the specific hepatocyte subpopulation of origin is yet to be determined. The relationship between the cancer cell of origin(CCO) and cancer-propagating cells, known as hepatic cancer stem cell(HCSC) is unknown. It has been challenging to identify the definitive phenotypic marker of HCSC, probably due to the existence of different cancer stem cells(CSC) subpopulations with different functions within HCC. There is a dynamic interconversion among different CSCs, and between CSC and non-CSCs. Because of that, CSC-state is currently defined as a description of a highly adaptable and dynamic intrinsic property of tumor cells, instead of a static subpopulation of a tumor. Altered conditions could trigger the gain of stemness, some of them include: EMT-MET, epigenetics, microenvironment and selective stimulus such as chemotherapy. This CSC heterogeneity and dynamism makes them out reach from therapeutic protocols directed to a single target. A further avenue of research in this line will be to uncover mechanisms that trigger this interconversion of cell populations within tumors and target it.

关键词： Cancer stem cell Liver progenitor cell Liver stem progenitor cell Stemness Plasticity Cancer cell of origin Cancer stem cells subpopulations

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Algorithm for repairing the damaged images of grain structures obtained from the cellular automata and measurement of grain size

引用

International Journal of Minerals,Metallurgy and Materials 2012年第10期19卷 899-907页

作者： A.Ramírez-López M.A.Romero-romo D.Muñoz-Negron S.López-Ramírez R.Escarela-Pérez C.Duran-Valencia Department of Materials and Energy Metropolitan Autonomous UniversityMexico City 02200Mexico Department of Industrial Engineering Technological Autonomous Institute of MexicoMexico City 01080Mexico Department of Molecular Engineering Mexican Institute of PetroleumMexico City 07730Mexico

Computational models are developed to create grain structures using mathematical algorithms based on the chaos theory such as cellular automaton, geometrical models, fractals, and stochastic methods. Because of the chaotic nature of grain structures, some of the most popular routines are based on the Monte Carlo method, statistical distributions, and random walk methods, which can be easily programmed and included in nested loops. Nevertheless, grain structures are not well defined as the results of computational errors and numerical incon- sistencies on mathematical methods. Due to the finite definition of numbers or the numerical restrictions during the simulation of solidifica- tion, damaged images appear on the screen. These images must be repaired to obtain a good measurement of grain geometrical properties. Some mathematical algorithms were developed to repair, measure, and characterize grain structures obtained from cellular automata in the present work. An appropriate measurement of grain size and the corrected identification of interfaces and length are very important topics in materials science because they are the representation and validation of mathematical models with real samples. As a result, the developed al- gorithms are tested and proved to be appropriate and efficient to eliminate the errors and characterize the grain structures.

关键词： grain size and shape image restoration mathematical algorithms cellular automata solidification

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Influence of Data Clouds Fusion From 3D RealTime Vision System on Robotic Group Dead Reckoning in Unknown Terrain

引用

IEEE/CAA Journal of Automatica Sinica 2020年第2期7卷 368-385页

作者： Mykhailo Ivanov Oleg Sergyienko Vera Tyrsa Lars Lindner Wendy flores-Fuentes Julio Cesar Rodriguez-Quinonez Wilmar Hernandez Paolo Mercorelli Universidad Autónoma de Baja California MexicaliB.C.21100Mexico Universidad de Las Américas Quito 170125Equador Leuphana University of Lueneburg Lüneburg 21335Germany

This paper proposes the solution of tasks set required for autonomous robotic group behavior optimization during the mission on a distributed area in a cluttered hazardous *** navigation scheme uses the benefits of the original real-time technical vision system(TVS)based on a dynamic triangulation *** method uses TVS output data with fuzzy logic rules processing for resolution *** on previous researches,the dynamic communication network model is modified to implement the propagation of information with a feedback method for more stable data exchange inside the robotic *** to the comparative analysis of approximation methods,in this paper authors are proposing to use two-steps post-processing path planning aiming to get a smooth and energy-saving *** article provides a wide range of studies and computational experiment results for different scenarios for evaluation of common cloud point influence on robotic motion planning.

关键词： Data transfer group behavior machine vision navigation robotic group(RG) vision system

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Pronuclear formation by ICSI using chemically activated ovine oocytes and zona pellucida bound sperm

引用

Journal of Animal Science and Biotechnology 2017年第2期8卷 370-377页

作者： J.E.Hernández-Pichardo Y.Ducolomb S.romo M.E.Kjelland R.Fierro F.Casillas M.Betancourt División de Ciencias Biológicas y de la Salud Departamento de Producción Agrícola y AnimalUniversidad Autónoma Metropolitana-XochimilcoCiudad de MexicoMexico Division de Ciencias Biologicas y de la Salud Departamento de Ciencias de la SaludUniversidad Autónoma Metropolitana-IztapalapaSan Rafael Atlixco 186CP 09340 Ciudad de MexicoMexico Departamento de Ciencias Pecuarias Facultad de EstudiosSuperiores CuautitlanUNAMCiudad de MexicoEstado de MexicoMexico Conservation Genetics&BiotechLLCValley CityNDUSA Division de Ciencias Biologicas y de la Salud Departamento de Biologia de la ReproduccionUniversidad Autonoma Metropolitana-lztapalapaCiudad de MexicoMexico Doctorado en Biologia Experimental Universidad Autonoma Metropolitana-lztapalapaCiudad de MexicoMexico

Background： In order to improve ICSI, appropiate sperm selection and oocyte activation is necessary. The objective of the present study was to determine the efficiency of fertilization using ICSI with chemically activated ovine oocytes and sperm selected by swim up（SU） or swim up ＋ zona pellucida（SU ＋ ZP） ***： Experiment 1, 4–20 replicates with total 821 in vitro matured oocytes were chemically activated with ethanol, calcium ionophore or ionomycin, to determine oocyte activation（precense of one PN）. Treatments showed similar results（54, 47, 42 %, respectively） but statistically differents（P 0.05）.Conclusions： Chemical activation induces higher ovine oocyte activation than mechanical activation. Ethanol slightly displays higher oocyte activation than calcium ionophore and ionomicine. Sperm selection with SU ＋ ZP increased AR/A and AR/D rates in comparison with SU in fresh and frozen-thawed sperm. According to this, in terms of fertilization rates, chemical activation after ICSI increased oocyte PN formation compared to mechanical activation. Also, fresh sperm treated with SU and SU ＋ ZP were significantly different than frozen-thawed sperm,but between sperm treatments no significant differences were obtained.

关键词： Ethanol ICSI Oocyte activation Ovine Pronucleus Zona pellucida

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Boron-modified perhydropolysilazane towards facile synthesis of amorphous SiBN ceramic with excellent thermal stability

引用

Journal of Advanced Ceramics 2022年第7期11卷 1104-1116页

作者： Ying ZHAN Wei LI Tianshu JIANG Claudia FASEL Emmanuel III RICOHERMOSO Jan BERNAUER Zhaoju YU Zhenghao WU Florian MÜLLER-PLATHE leopoldo MOLINA-LUNA Ralf GROTTENMÜLLER Ralf RIEDEL Department of Materials and Earth Sciences Technical University of DarmstadtD-64287 DarmstadtGermany College of Materials Key Laboratory of High Performance Ceramic Fibers(Xiamen University)Ministry of EducationXiamen 361005China Eduard-Zintl-Institut für Anorganische und Physikalische Chemie Technical University of DarmstadtD-64287 DarmstadtGermany Merck KGaA Performance MaterialsD-64293DarmstadtGermany

SiBN ceramics are widely considered to be the most promising material for microwavetransparent applications in harsh environments owing to its excellent thermal stability and low dielectric *** work focuses on the synthesis and ceramization of single-source precursors for the preparation of SiBN ceramics as well as the investigation of the corresponding microstructural evolution at high temperatures including molecular dynamic ***-and chlorine-free perhydropolysilazanes were reacted with borane dimethyl sulfide complex at different molar ratios to synthesize single-source precursors,which were subsequently pyrolyzed and annealed under N2 atmosphere(without ammonolysis)to prepare SiBN ceramics at 1100,1200,and 1300℃with high ceramic yield in contrast to previously widely-used ammonolysis synthesis *** obtained amorphous SiBN ceramics were shown to have remarkably improved thermal stability and oxidation resistance compared to amorphous silicon ***,the experimental results have been combined with molecular dynamics simulation to further study the amorphous structure of SiBN and the atomic-scale diffusion behavior of Si,B,and N at 1300℃.Incorporation of boron into the Si–N network is found to suppress the crystallization of the formed amorphous silicon nitride and hence improves its thermal stability in N2 atmosphere.

关键词： polymer-derived ceramics(PDCs) SiBN crystallization molecular dynamics oxidation resistanc

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Growth retardation and severe anemia in children with Trichuris dysenteric syndrome

引用

Asian Pacific Journal of Tropical Biomedicine 2015年第7期5卷 581-586页

作者： Rina Girard Kaminsky Renato Valenzuela Castillo Coralia Abrego flores Pediatric Department School of Medicine National Autonomous University of Honduras and Service of Parasitology University Hospital Honduras.P.O.Box 1547Tegucigalpa Honduras Pediatric Department School of Medicine National Autonomous University of Honduras Pediatric Psychology Unit University HospitalHonduras

Objective: To document epidemiologic data, clinical manifestations and treatment in hospitalized children with Trichuris dysenteric syndrome from Honduras during 2010-2012. Methods: Severe trichuriasis cases were identified by routine stool examinations from hospitalized patients(12 years old or less). Relevant epidemiologic, clinical and management data were obtained from review of clinical histories in the ward. Results: Of 122 Trichuris infections diagnosed in 11 528(1.0%) stool samples for all ages, 81(66.4%) were identified in the age group 2-12 years old, 21(25.9%) of which were severe(≥ 100 eggs in 2 mg of feces). Thirteen of those 21 patients collaborated in this study. Patients(9 males and 4 females) were of rural precedence, from large poor or very poor families, chronically parasitized, and between 2 and 12 years old. Dysentery of months duration, severe anemia and stunting were common complaints; clinical characteristics associated with heavy Trichuris infections included egg counts from 232-3 520 eggs per direct smear, hemoglobin from 3.4-10.8 g/d L, eosinophilia up to 43%, severe malnutrition and growth stunting. Orally administered drugs mebendazole, albendazole, metronidazole, nitaxozanide, and piperazine were prescribed at different dosages and duration other than recommended; no cure or egg excretion control was exercised before patient release. A range of 340 to about 10 000 worms were recovered after treatment from 8 patients. Conclusions: This report underlines the need for detailed community studies in trichuriasis morbidity, effective treatment assessment and clinical response in severely malnourished parasitized children.

关键词： Anemia Honduras Stunting Trichuris dysentery syndrome

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Polyoxidovanadates a new therapeutic alternative for neurodegenerative and aging diseases

引用

Neural Regeneration Research 2024年第3期19卷 571-577页

作者： Sonia Irais Gonzalez-Cano Gonzalo flores Jorge Guevara Julio Cesar Morales-Medina Samuel Treviño Alfonso Diaz Faculty of Chemical Sciences Benemerita Autonomous University of PueblaPueblaMexico Institute of Physiology Benemerita Autonomous University of PueblaPueblaMexico Department of Biochemistry Faculty of MedicineNational Autonomous University of MexicoMexico CityMexico Animal Reproduction Research Center CINVESTAV-Autonomous University of TlaxcalaTlaxcalaMexico

Aging is a natural phenomenon characterized by a progressive decline in physiological integrity,leading to a deterioration of cognitive function and increasing the risk of suffering from chronic-degenerative diseases,including cardiovascular diseases,osteoporosis,cancer,diabetes,and *** is considered the major risk factor for Parkinson’s and Alzheimer’s disease ***,diabetes and insulin resistance constitute additional risk factors for developing neurodegenerative ***,no treatment can effectively reverse these neurodegenerative ***,some antidiabetic drugs have opened the possibility of being used against neurodegenerative *** the previous framework,Vanadium species have demonstrated a notable antidiabetic *** research group evaluated polyoxidovanadates such as decavanadate and metforminium-decavanadate with preventive and corrective activity on neurodegeneration in brain-specific areas from rats with metabolic *** results suggest that these polyoxidovanadates induce neuronal and cognitive restoration *** review aims to describe the therapeutic potential of polyoxidovanadates as insulin-enhancer agents in the brain,constituting a therapeutic alternative for aging and neurodegenerative diseases.

关键词： Alzheimer’s disease antidiabetic brain cognition diabetes insulin neurodegeneration neuroinflammation oxidative stress Vanadium species

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Characterization, conservation and sustainability of endangered animal breeds in Campania (Southern Italy)

引用

Natural Science 2013年第5期5卷 1-9页

作者： Vincenzo Peretti Francesca Ciotola leopoldo Iannuzzi Department of Veterinary Medicine and Animal Production University Federico II Naples Italy Francesca Ciotola Department of Health Science University of Catanzaro Catanzaro Italy National Research Council Institute of Animal Production Systems in Mediterranean Environments Naples Italy

Conservation of such animal genetic resources and sustainable development of their products seems to be one of the most important steps to be taken to save endangered animal breeds from the widespread use of cosmopolitan and more productive breeds. Indeed, the protection and conservation of biodiversity of animal breeds adapted to particular environmental conditions is essential to prevent irreversible erosion of genes and gene combinations. A special project to characterize and conserve eight endangered breeds of various animal species raised in Campania (southern-Italy) is reported in this paper along detailed descriptions of all breeds. Some strategies for their characterization and conservation are reported and discussed.

关键词： Endangered Breed Livestock

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

State of the art in neurocysticercosis

引用

Asian Pacific Journal of Tropical Medicine 2016年第8期9卷 798-799页

作者： Arturo Carpio Matthew L.romo Escuela de Medicina Universidad de Cuenca GH Sergievsky Center College of Physicians and Surgeons Columbia University CUNY School of Public Health

Diagnosis of neurocysticercosis(NCC)based merely on computed tomography(CT)and magnetic resonance imaging may be doubtful when considering that parenchymal and extraparenchymal NCC are practically distinct clinical an... 详细信息

关键词： Neurocysticercosis Cysticercosis Taenia solium Diagnosis Therapeutics Epidemiology

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：