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Chinese Chemical Letters 2009年第8期20卷 909-912页

作者： m.Saranga Pani m.Arjun D.Sridhar K.Srinivas T.Raviprasad Department of Pharmacy Kakatiya University Department of Chemistry Kakatitya University

An efficient synthesis of 3,4-dihydropyrimidine 2 （1H）-ones and thiones （3,4-DHPms） core was prepared by one-pot threecomponent Biginelli condensation and which was catalyzed by trifluoromethane sulfonic acid. The classical BigneUi reaction has been extended by the use of N-substituted benzoxazolyl semicarbazides and thiosemicarbazides and this method has the advantage of excellent yields and short reaction times. ？2009 m. Saranga Pard. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Trifluoromcthane sulfonic acid N-substituted scmicarbazidcs and thioscmicarbazidcs β-Ketocster Substituted benzoxazolyl 3,4-dihydropyrimidinc (IH)-(thio)-ones

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HIGH-ORDER EXPLICIT TImE-INTEGRATORS FOR DISCONTINUOUS GALERKIN DISCRETIZATIONS OF THE mAXWELL EQUATIONS

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International Journal of modeling, Simulation, and Scientific Computing 2013年第1期4卷 132-153页

作者： H.FAHS m.SAFA LAmA Laboratory University Paris-Est Marne-la-Vallee UMR CNRS 80505 boulevard Descartes 77454 Marne-la-Vall´ee Cedex 2France INRIA Paris-Rocquencourt Domaine de Voluceau BP.10578153 Le Chesnay CedexFrance

We investigate the practical implementation of a high-order explicit time-stepping method based on polynomial approximations,for possible application to large-scale problems in *** the spatial discretization by a high-order discontinuous Galerkin method,we obtain a linear system of differential equations of the form,∂tY(t)=HY(t)+S(t),where H is a matrix containing the spatial derivatives and t is the time *** formal solution can be written in terms of the matrix exponential,exp(tH),acting on some *** introduce a general family of time-integrators based on the approximation of exp(tH)by Jacobi polynomial *** discuss the efficient implementation of this technique,and based on some test problems,we compare the virtues and shortcomings of the *** also demonstrate how these schemes provide an efficient alternative to standard explicit integrators for computing solutions over long time intervals.

关键词： maxwell’s equations discontinuous Galerkin method time-stepping schemes

Numerical simulation of wave scouring beneath marine pipeline using smoothed particle hydrodynamics

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International Journal of Sediment Research 2011年第3期26卷 331-342页

作者： A.mIRmOHAmmADI m.J.KETABDARI Faculty of marine Technology Amirkabir University of Technology424 Hafez AvenueTehran-IranP.O.

In this paper a smoothed particle hydrodynamics(SPH)approach is presented to simulate scouring due to wave around a marine pipeline on a sloping sea *** proposed method is similar to socalled SPH projection method and consists of three *** first two steps play the role of prediction,while in the third step a Poisson Equation is used for both fluid and sea bed to impose incompressibility *** is assumed that the sandy sediments around pipeline section which represent the variable boundary and scour profile,behave as a non-Newtonian *** scouring below a pipe under waves in a test flume with a piston wave maker and sandy sloping bed is estimated using Newtonian-non Newtonian fluid flow interaction *** Bingham model is cautiously utilized for simulation of the sea bed *** results with or without viscosity were compared with analytical,empirical and experimental results and a reasonable agreement was *** show that the developed model is a powerful tool to simulate complex free surface and Newtonian-non Newtonian fluid interaction problems.

关键词： Wave scouring Numerical simulation Free surface marine pipeline SPH method

Role of vascular endothelial growth factor as a critical neurotrophic factor for the survival and physiology of motoneurons

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Neural Regeneration Research 2023年第8期18卷 1691-1696页

作者： Paula m.Calvo Rosendo G.Hernández Rosa R.de la Cruz Angel m.Pastor Departamento de Fisiología Facultad de BiologíaUniversidad de SevillaSevillaSpain

Vascular endothelial growth factor(VEGF)was discovered by its angiogenic ***,during evolution,it appeared earlier as a neurotrophic factor required for the development of the nervous system in invertebrates lacking a circulatory *** aimed at reviewing recent evidence indicating that VEGF has neuroprotective effects in neurons exposed to a variety of *** particular interest is the link established between VEGF and motoneurons,especially after the design of the VEGFδ/δmutant *** mice are characterized by low levels of VEGF and develop muscle weakness and motoneuron degeneration resembling amyotrophic lateral *** administration of VEGF through several routes to animal models of amyotrophic lateral sclerosis delays motor impairment and motoneuron degeneration and increases life *** are new recent advances in the role of VEGF in the physiology of *** experimental aims use the extraocular(abducens)motoneurons lesioned by axotomy as a model for studying VEGF *** abducens motoneurons exhibit severe alterations in their discharge activity and a loss of synaptic *** exogenous administration of VEGF to axotomized abducens motoneurons,either from the transected nerve or intraventricularly,fully restores the synaptic and discharge properties of abducens motoneurons,despite being *** addition,when an anti-VEGF neutralizing antibody is delivered from the muscle to intact,uninjured abducens motoneurons,these cells display alterations in their discharge pattern and a loss of synaptic boutons that resemble the state of *** these data indicate that VEGF is an essential neurotrophic factor for motoneurons.

关键词： abducens nucleus amyotrophic lateral sclerosis cell death extracellular single-unit recordings eye movements neurodegeneration oculomotor trophic factors

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Fragment antigen binding domains (F_(ab)s) as tools to study assembly-line polyketide synthases

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Synthetic and Systems Biotechnology 2022年第1期7卷 506-512页

作者： Katarina m.Guzman Chaitan Khosla Department of Chemical Engineering Stanford UniversityStanfordCA94305USA Department of Chemistry Stanford ChEM-HStanford UniversityStanfordCA94305USA

The crystallization of proteins remains a bottleneck in our fundamental understanding of their ***,discovering tools that aid crystallization is *** this review,the versatility of fragment-antigen binding domains(F_(ab)s)as protein crystallization chaperones is discussed.F_(ab)s have aided the crystallization of membrane-bound and soluble proteins as well as *** ability to bind three F_(ab)s onto a single protein target has demonstrated their potential for crystallization of challenging *** describe a high-throughput workflow for identifying F_(ab)s to aid the crystallization of a protein of interest(POI)by leveraging phage display technologies and differential scanning fluorimetry(DSF).This workflow has proven to be especially effective in our structural studies of assembly-line polyketide synthases(PKSs),which harbor flexible domains and assume transient *** are of interest to us due to their ability to synthesize an unusually broad range of medicinally relevant *** years of research studying these megasynthases,their overall topology has remained *** F ab in particular,1B2,has successfully enabled X-ray crystallographic and single particle cryo-electron microscopic(cryoEm)analyses of multiple modules from distinct assembly-line *** use has not only facilitated multidomain protein crystallization but has also enhanced particle quality via cryoEm,thereby enabling the visualization of intact PKS modules at near-atomic(3–5Å)*** identification of PKS-binding F_(ab)s can be expected to continue playing a key role in furthering our knowledge of polyketide biosynthesis on assembly-line PKSs.

关键词： Crystallography Cryo-Em Polyketide synthases Fragment antigen binding domains

Disagreements in the therapeutic use of mesenchymal stem cellderived secretome

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World Journal of Stem Cells 2022年第6期14卷 365-371页

作者： Ferenc Sipos Györgyi műzes Department of Internal medicine and Hematology Semmelweis UniversityBudapest 1088Hungary

In a recent article,the authors provide a detailed summary of the characteristics and biological functions of mesenchymal stem cells(mSCs),as well as a discussion on the potential mechanisms of action of mSC-based *** describe the morphology,biogenesis,and current isolation techniques of exosomes,one of the most important fractions of the mSC-derived *** also summarize the characteristics of mSC-derived exosomes and highlight their functions and therapeutic potential for tissue/organ regeneration and for kidney,liver,cardiovascular,neurological,and musculoskeletal diseases,as well as cutaneous wound *** the fact that mSCs are regarded as an important pillar of regenerative medicine,their regenerative potential has been demonstrated to be limited in a number of pathological *** negative effects of mSC-based cell therapy have heightened interest in the therapeutic use of mSC-derived *** the other hand,mSC-derived exosomes and microvesicles possess the potential to have a significant impact on disease development,including *** can interact with tumor cells and promote mutual exchange and induction of cellular markers by exchanging ***,enzymes secreted into and activated within exosomes can result in tumor cells acquiring new *** a result,therapeutic applications of mSC-derived secretomes must be approached with extreme caution.

关键词： mesenchymal stem cells Secretome Exosomes Regeneration Therapy Cancer

Fecal incontinence - Challenges and solutions

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World Journal of Gastroenterology 2017年第1期23卷 11-24页

作者： Nallely Saldana Ruiz Andreas m Kaiser Department of Surgery Division of Colorectal SurgeryKeck School of MedicineUniversity of Southern California Department of Surgery Division of Colorectal SurgeryKeck School of MedicineUniversity of Southern California

Fecal incontinence is not a diagnosis but a frequent and debilitating common final pathway symptom resulting from numerous different causes. Incontinence not only impacts the patient’s self-esteem and quality of life but may result in significant secondary morbidity, disability, and cost. Treatment is difficult without any panacea and an individualized approach should be chosen that frequently combines different modalities. Several new technologies have been developed and their specific roles will have to be defined. The scope of this review is outline the evaluation and treatment of patients with fecal incontinence.

关键词： Fecal incontinence Sphincteroplasty Sacral nerve stimulation Endorectal ultrasound New technologies Quality of life

Therapy for alcoholic liver disease

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World Journal of Gastroenterology 2014年第9期20卷 2143-2158页

作者： maryconi m Jaurigue mitchell S Cappell Division of Gastroenterology and Hepatology Department of Internal MedicineWilliam Beaumont Hospital Royal Oak MI 48073 United States Oakland University William Beaumont School of medicine Royal Oak MI 48073 United States

Alcoholism results in about 2.5 million deaths annually worldwide, representing 4% of all mortality. Although alcoholism is associated with more than 60 diseases, most mortality from alcoholism results from alcoholic liver disease (ALD). ALD includes alcoholic steatosis, alcoholic hepatitis, and alcoholic cirrhosis, in order of increasing severity. Important scoring systems of ALD severity include: Child-Pugh, a semi-quantitative scoring system useful to roughly characterize clinical severity; model for end-stage liver disease, a quantitative, objective scoring system used for prognostication and prioritization for liver transplantation; and discriminant function, used to determine whether to administer corticosteroids for alcoholic hepatitis. Abstinence is the cornerstone of ALD therapy. Psychotherapies, including twelve-step facilitation therapy, cognitive-behavioral therapy, and motivational enhancement therapy, help support abstinence. Disulfiram decreases alcohol consumption by causing unpleasant sensations after drinking alcohol from accumulation of acetaldehyde in serum, but disulfiram can be hepatotoxic. Adjunctive pharmacotherapies to reduce alcohol consumption include naltrexone, acamprosate, and baclofen. Nutritional therapy helps reverse muscle wasting, weight loss, vitamin deficiencies, and trace element deficiencies associated with ALD. Although reduced protein intake was previously recommended for advanced ALD to prevent hepatic encephalopathy, a diet containing 1.2-1.5 g of protein/kg per day is currently recommended to prevent muscle wasting. Corticosteroids are first-line therapy for severe alcoholic hepatitis (discriminant function ≥ 32), but proof of their efficacy in decreasing mortality remains elusive. Pentoxifylline is an alternative therapy. Complications of advanced ALD include ascites, spontaneous bacterial peritonitis, esophageal variceal bleeding, hepatic encephalopathy, hepatorenal syndrome, hepatopulmonary syndrome, and portopu

关键词： Alcoholic liver disease Alcoholic steatosis Alcoholic hepatitis Alcoholic cirrhosis Alcoholism Liver disease Corticosteroids Pentoxifylline Liver transplantation

Temperature dependence of InAs/GaAs quantum dots solar photovoltaic devices

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Journal of Semiconductors 2014年第5期35卷 21-25页

作者： E.Garduno-Nolasco m.missous D.Donoval J.Kovac m.mikolasek School of Electrical and Electronic Engineering.The University of manchester Institute of Electronics and Photonics Slovak University of Technology

This paper presents the temperature dependence measurements characterisation of several InAs/GaAs quantum dots （QDs） solar cell devices. The devices with cylindrical geometry were fabricated and characterised on-wafer under 20 suns in a temperature range from 300°K to 430°K. The temperature dependence parameters such as open circuit voltage, short circuit density current, fill factor and efficiency are studied in detail. The increase of temperature produces an enhancement of the short circuit current. However, the open circuit voltage is degraded because the temperature increases the recombination phenomena involved, as well as reducing the effective band gap of the semiconductor.

关键词： quantum dots solar cells III-V semiconductors inter-dot doping efficiency temperature depen- dence

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Glycogen storage diseases:An update

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World Journal of Gastroenterology 2023年第25期29卷 3932-3963页

作者： Ersin Gümüs Hasan Ozen Department of Pediatric Gastroenterology Hepatology and NutritionHacettepe University Faculty of MedicineIhsan Dogramaci Children’s HospitalAnkara 06230Turkey

Glycogen storage diseases(GSDs),also referred to as glycogenoses,are inherited metabolic disorders of glycogen metabolism caused by deficiency of enzymes or transporters involved in the synthesis or degradation of glycogen leading to aberrant storage and/or *** overall estimated GSD incidence is 1 case per 20000-43000 live *** are over 20 types of GSD including the *** heterogeneous group of rare diseases represents inborn errors of carbohydrate metabolism and are classified based on the deficient enzyme and affected *** primarily affect liver or muscle or both as glycogen is particularly abundant in these ***,besides liver and skeletal muscle,depending on the affected enzyme and its expression in various tissues,multiorgan involvement including heart,kidney and/or brain may be *** GSDs share similar clinical features to some extent,there is a wide spectrum of clinical ***,the goal of treatment is to maintain glucose homeostasis by dietary management and the use of uncooked *** addition to nutritional interventions,pharmacological treatment,physical and supportive therapies,enzyme replacement therapy(ERT)and organ transplantation are other treatment approaches for both disease manifestations and longterm *** lack of a specific therapy for GSDs has prompted efforts to develop new treatment strategies like gene *** early diagnosis and aggressive treatment are related to better prognosis,physicians should be aware of these conditions and include GSDs in the differential diagnosis of patients with relevant manifestations including fasting hypoglycemia,hepatomegaly,hypertransaminasemia,hyperlipidemia,exercise intolerance,muscle cramps/pain,rhabdomyolysis,and muscle ***,we aim to provide a comprehensive review of *** review provides general characteristics of all types of GSDs with a focus on those with liver involvement.

关键词： Glycogen storage disease Liver muscle Hypoglycemia