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IEEE/CAA Journal of Automatica Sinica 2024年第9期11卷 1967-1972页

作者： Gopi ram Department of Electronics and Communication Engineering National Institute of TechnologyWarangal 506004India

The concept of the time-modulated array has been emerging as an alternative to the complex phase shifters,which lowers the cost of the array feeding network due to the utilization of radio frequency(RF)*** various forms of hexagonal antenna array geometries can be used for applications like surveillance tracking in phased array radar and wireless communication *** work proposes the generalized array factor(AF)for the hexagonal antenna array geometry based on time *** time modulation in generalized hexagonal geometry can maintain the fixed static amplitude excitation,giving more flexibility over ***,a novel trapezoidal switching function is also proposed and applied to the generalized array factor to enable future researchers to use this array factor in the field of advancement to observe how switching schemes like trapezoidal and rectangular affect the array pattern's side lobe level(Sll).The generalized equation can be utilized for the analysis and synthesis of radiation characteristics of the time-modulated hexagonal array(TMHA),time-modulated concentric hexagonal array(TMCHA),time-modulated hexagonal cylindrical array(TMHCA),and time-modulated hexagonal concentric cylindrical array(TMHCCA).The numerical result illustrates the generation of AF of time-modulated hexagonal structures and also shows that the trapezoidal switching sequence outperforms the rectangular switch using the cat swarm optimization(CSO)approach.

关键词： Hexagonal array geometry radiation pattern time-modulation trapezoidal pulse

High Temperature Oxidation of a Work Roll Grade High-Chromium White Cast Iron

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Journal of Iron and Steel Research International 2013年第10期20卷 122-129页

作者： J H ramírez-ramírez R Colás n F Garza-Montes-de-Oca Faculty of Mechanical and Electrical Engineering Autonomous University of Nuevo Leon

High-chromium white cast iron is a common material for the manufacture of the work rolls used in the fin- ishing stands in hot strip mills. The high temperature oxidation behaviour of as-cast and heat-treated high-chromium white cast iron was studied by gravimetric means at 650 ℃ in atmospheres that included dry air and a mixture of dry air and water vapour. For both environmental and material conditions, the oxidation rate of the alloys was represen ted by parabolic trends and the oxidation phenomenon was more obvious when the samples were oxidised in water vapour. Water vapour also influenced the chemical composition of the oxides formed in the alloy and under this condi tion, the oxide scale formed on the alloy contained the oxides FeCr2O4 , （Fe,Cr）3O4 and （Fe,Cr）2 O3. In contrast, the alloys exposed to dry air conditions only experienced the formation of FeCr2O4 and （Fe,Cr）2O3. It was found that the presence of water vapour and the chromium content of the alloys increased the oxidation rate by a mechanism that involved chromium depletion of the oxide as a result of hydroxide formation. The differences observed in the oxi- dation behaviour of the alloy are discussed in terms of the composition of the oxidant atmosphere and the metallurgi cal condition of the specimens.

关键词： white cast iron oxidation water vapour work roll

Common misconceptions about 5-aminosalicylates and thiopurines in inflammatory bowel disease

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World Journal of Gastroenterology 2011年第30期17卷 3467-3478页

作者： Javier P Gisbert maría Chaparro Fernando Gomollón Gastroenterology Unit Hospital Universitario de La PrincesaInstituto de Investigación SanitariaPrincesa(IP)and Centro de Investigación Biomédica en Red de Enfermedades Hepáticasy Digestivas28006 MadridSpain Gastroenterology Unit Hospital Clínico Universitario and Centro de Investigación Biomédica en Redde Enfermedades Hepáticasy DigestivasIACS50009 ZaragozaSpain

Misconceptions are common in the care of patients with inflammatory bowel disease(IBD).In this paper,we state the most commonly found misconceptions in clinical practice and deal with the use of 5-aminosalicylates and thiopurines,to review the related scientificevidence,and make appropriate *** of errors needs knowledge to avoid making such errors through ***,the amount of knowledge is increasing so quickly that one new danger is an overabundance of *** is a model of a very complex disease and our goal with this review is to summarize the key evidence for the most common daily clinical *** regard to the use of 5-aminosalicylates,the best practice may to be consider abandoning the use of these drugs in patients withsmall bowel Crohn's *** combined approach with oral plus topical 5-aminosalicylates should be the first-line therapy in patients with active ulcerative colitis;once-daily treatment should be offered as a first choice regimen due to its better compliance and higher *** regard to thiopurines,they seem to be as effective in ulcerative colitis as in Crohn's *** of thiopurines is a form of *** should probably be continued indefinitely because their withdrawal is associated with a high risk of *** is a safe alternative in patients with digestive intolerance or hepatotoxicity due to ***,thiopurine methyltransferase(TPMT)screening cannot substitute for regular monitoring because the majority of cases of myelotoxicity are not TPMT-related.

关键词： Crohn' s disease Ulcerative colitis Inflam-matory bowel disease Aminosalicylates Steroids Azathioprine Mercaptopurine Misconceptions

Hierarchical and selective roles of galectins in hepatocarcinogenesis, liver fibrosis and inflammation of hepatocellular carcinoma

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World Journal of Gastroenterology 2013年第47期19卷 8831-8849页

作者： maría l Bacigalupo Malena Manzi Gabriel A Rabinovich maría F Troncoso Institute of Biological Chemistry and Biophysics "Prof. Alejandro C. Paladini" (UBA-COnICET) Department of Biological ChemistrySchool of Pharmacy and BiochemistryUniversity of Buenos AiresC1113AADBuenos AiresArgentina Institute of Biology and Experimental Medicine (COnICET) Department of Biological ChemistrySchool of Exact and Natural SciencesUniversity of Buenos AiresC1113AAD Buenos AiresArgentina

Hepatocellular carcinoma(HCC)represents a global health *** with hepatitis B or C virus,non-alcoholic steatohepatitis disease,alcohol abuse,or dietary exposure to aflatoxin are the major risk factors to the development of this *** of the carcinogenic insult,HCC usually develops in a context of cirrhosis due to chronic inflammation and advanced *** are a family of evolutionarily-conserved proteins defined by at least one carbohydrate recognition domain with affinity forβ-galactosides and conserved sequence ***,we summarize the current literature implicating galectins in the pathogenesis of *** of"proto-type"galectin-1,"chimera-type"galectin-3 and"tandem repeat-type"galectin-4 is up-regulated in HCC cells compared to their normal *** the other hand,the"tandemrepeat-type"lectins galectin-8 and galectin-9 are downregulated in tumor *** abnormal expression of these galectins correlates with tumor growth,HCC cell migration and invasion,tumor aggressiveness,metastasis,postoperative recurrence and poor ***,these galectins have important roles in other pathological conditions of the liver,where chronic inflammation and/or fibrosis take ***-based therapies have been proposed to attenuate liver *** functional studies are required to delineate the precise molecular mechanisms through which galectins contribute to HCC.

关键词： Galectins Hepatocellular carcinoma Inflammation-associated liver injury Hepatitis B or C virus infection-associated hepatocellular carcinoma Fibrosis-related liver pathologies

Steroid-refractory ulcerative colitis and associated primary sclerosing cholangitis treated with infliximab

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World Journal of Gastroenterology 2013年第4期19卷 590-593页

作者： Ileana Duca Patricia ramírez de la Piscina Silvia Estrada Rosario Calderón Katerina Spicakova leire Urtasun Carlos marra-lópez Salvador Zabaleta Raquel Bengoa maría Asunción marcaide Francisco García-Campos Service of Gastroenterology Hospital Universitario de álava-Sede TxagorritxuUniversidad del País VascoE-01009 Vitoria-GasteizSpain

Primary sclerosing cholangitis is an infrequent extraintestinal manifestation of ulcerative *** to bile ducts is irreversible and medical therapies to prevent progression of the disease are usually *** describe a patient with long-standing ulcerative colitis,which was refractory to corticosteroid therapy who developed primary sclerosing cholangitis(biochemical stage Ⅱ/Ⅳ) in the course of his *** with infliximab(5 mg/kg as an induction dose followed by maintenance doses every two months) was indicated because of steroid-dependent disease associated to primary sclerosing cholangitis as well as sacroiliitis and uveitis and previous episode of severe azathioprinerelated hepatic *** present,after two years of follow-up,the patient is asymptomatic with normal liver tests and complete resumption of daily life *** case draws attention to the usefulness of antitumor necrosis factor-alpha therapy for the management of primary sclerosing cholangitis as extraintestinal manifestation of inflammatory bowel disease.

关键词： Ulcerative colitis Infliximab Monoclonal antibodies Sclerosing cholangitis Bile duct diseases Tumor necrosis factor-alpha

Specific CD8^+ T cell response immunotherapy for hepatocellular carcinoma and viral hepatitis

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World Journal of Gastroenterology 2016年第28期22卷 6469-6483页

作者： Elia Moreno-Cubero Juan-ramón larrubia Translational Hepatology Unit Guadalajara University Hospital University of Alcalá Department of Biology of Systems University of Alcalá Department of Medicine and Medical Specialties University of Alcalá

Hepatocellular carcinoma (HCC), chronic hepatitis B (CHB) and chronic hepatitis C (CHC) are characterized by exhaustion of the specific CD8+ T cell response. This process involves enhancement of negative co-stimulatory molecules, such as programmed cell death protein-1 (PD-1), cytotoxic T-lymphocyte antigen-4 (CTlA-4), 2B4, Tim-3, CD160 and lAG-3, which is linked to intrahepatic overexpression of some of the cognate ligands, such as PD-l1, on antigen presenting cells and thereby favouring a tolerogenic environment. Therapies that disrupt these negative signalling mechanisms represent promising therapeutic tools with the potential to restore reactivity of the specific CD8+ T cell response. In this review we discuss the impressive in vitro and in vivo results that have been recently achieved in HCC, CHB and CHC by blocking these negative receptors with monoclonal antibodies against these immune checkpoint modulators. The article mainly focuses on the role of CTlA-4 and PD-1 blocking monoclonal antibodies, the first ones to have reached clinical practice. The humanized monoclonal antibodies against CTlA-4 (tremelimumab and ipilimumab) and PD-1 (nivolumab and pembrolizumab) have yielded good results in testing of HCC and chronic viral hepatitis patients. Trelimumab, in particular, has shown a significant increase in the time to progression in HCC, while nivolumab has shown a remarkable effect on hepatitis C viral load reduction. The research on the role of ipilimumab, nivolumab and pembrolizumab on HCC is currently underway.

关键词： Hepatocellular carcinoma CD8+ T cells Immune checkpoint modulation Chronic viral hepatitis Cytotoxic T-lymphocyte antigen-4 Programmed cell death protein-1

Glutamine synthetase activity and glutamate uptake in hippocampus and frontal cortex in portal hypertensive rats

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World Journal of Gastroenterology 2009年第23期15卷 2893-2899页

作者： Gabriela Beatriz Acosta maría Alejandra Fernández Diego martín Roselló maría luján Tomaro Karina Balestrasse Abraham lemberg Institute of Pharmacological Research (InInFA) National Research Council of Argentina (CONICET) and University of Buenos Aires Junín 956. 5th floor C1113AAD Buenos Aires Argentina laboratory of Portal Hypertension School of Pharmacy and Biochemistry University of Buenos Aires Junín 956. 5th floor C1113AAD Buenos Aires Argentina Department of Biological Chemistry School of Pharmacy and Biochemistry University of Buenos Aires Junín 596. 5th floor C1113AAD Buenos Aires Argentina

AIM: To study glutamine synthetase (GS) activity and glutamate uptake in the hippocampus and frontal cortex (FC) from rats with prehepatic portal vein hypertension. METHODS: Male Wistar rats were divided into shamoperated group and a portal hypertension (PH) group with a regulated stricture of the portal vein. Animals were sacrificed by decapitation 14 d after portal vein stricture. GS activity was determined in the hippocampus and FC. Specific uptake of radiolabeled l-glutamate was studied using synaptosome-enriched fractions that were freshly prepared from both brain areas. RESUlTS: We observed that the activity of GS increased in the hippocampus of PH rats, as compared to control animals, and decreased in the FC. A significant decrease in glutamate uptake was found in both brain areas, and was more marked in the hippocampus. The decrease in glutamate uptake might have been caused by a deficient transport function, signif icantly and persistent increase in this excitatory neurotransmitter activity. COnClUSIOn: The presence of moderate ammonia blood levels may add to the toxicity of excitotoxic glutamate in the brain, which causes alterations in brain function. Portal vein stricture that causes portal hypertension modif ies the normal function in some brain regions.

关键词： Portal hypertension Glutamine synthetase Glutamate uptake Frontal cerebral cortex Hippocampus Rat

Calibration of the DEM sliding friction and rolling friction parameters of a cohesionless bulk material

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Particuology 2024年第9期92卷 126-139页

作者： Jonatan marín Pérez Tugrul Comlekci Yevgen Gorash Donald MacKenzie University of Strathclyde 75 Montrose StreetG11XJGlasgowUnited Kingdom

The discrete element method(DEM)has become a valuable tool for understanding the mechanical behaviour of granular assemblies,however,the accuracy of the DEM simulations depends on several interaction parameters such as the sliding friction and rolling friction ***,these parameters are estimated using bulk calibration approach(BCA)where the draw down test has been suggested as an effective way to approach these *** test provides up to four bulk criteria,the angle of repose,shear angle,mass flow rate and the mass loss which are used to narrow down the possible ***,there is still more research needed around it to fully understand how this methodology *** experimental and numerical study was carried out using the draw down test to assess the influence of different mass flow rates and particle shapes on DEM parameters for a cohesionless bulk *** is concluded that use of multi-sphere particles and three aperture sizes in the draw down test to calibrate the sliding and rolling friction parameters of a cohesionless bulk material can converge to a small feasible region in which a single combination of the friction coefficients can be *** calibrated sliding and rolling friction coefficients were validated using multi-sphere particles,where the maximum deviation was 5.9%from the experimental values.

关键词： Discrete element method Calibration Draw down Sliding friction Rolling friction Particle shape

Glutamine is highly effective in preventing in vivo cobalt-induced oxidative stress in rat liver

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World Journal of Gastroenterology 2005年第23期11卷 3533-3538页

作者： Soledad Gonzales Ariel H.Polizio maría A.Erario maría l.Tomaro Departamento de Química Biológica

AIM: To evaluate the in vivo effect of glutamine on cobaltgenerated oxidative stress and (HO-1) induction in rat ***: Fasted female Wistar rats received a single injection of cobalt chloride (375 μmol/kg body weight) and then were killed at different times. lipid peroxidation and soluble and enzymatic antioxidant defense system (reduced glutathione (GSH), catalase (CAT), glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD)) were measured in liver homogenates. Ferritin and ferritin iron contents as well as heme oxygenase-1 (HO-1) activity and expression were also determined. The antioxidant properties of glutamine (Gin) were also evaluated. RESUlTS: Cobalt chloride increased lipid peroxidation (50% over control values) 1 h after treatment. GSH reached a minimum at 3 h (40%) increasing thereafter. Twelve hours after CoCl2 injection, the antioxidant enzymes CAT, GSH-Px and SOD also diminished by about 30%. Heme oxygenase-1 induction was observed 6 h after treatment reaching a maximum value of 14-fold over the controls, 12 h after cobalt treatment. A 1.7-fold increase in ferritin and ferritin-bound iron 24 h after treatment were also obtained. Administration of glutamine (300 mg/kg body weight) by gavage 24 h before CoCl2 treatment entirely prevented the increase in thiobarbituric acid reactive substances (TBARS) content, the decrease in GSH levels, and partially reverted heme oxygenase-1 induction. COnClUSIOn: These results suggested that a natural product such as glutamine prevents glutathione depletion and consequently heme oxygenase induction.

关键词： Oxidative stress Heme oxygenase Glutathione Glutamine Iron liver

Caerulin-induced pancreatitis in rats: Histological and genetic expression changes from acute phase to recuperation

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World Journal of Gastroenterology 2006年第25期12卷 3999-4003页

作者： Javier Magaa-Gómez Guillermo lópez-Cervantes Ana maría Calderón de la Barca Departamento de nutrición Centro de Investigación en Alimentación y Desarrollo A.C. HermosilloSonoraMéxicoDepartamento de Patología Hospital Infantil del Estado de SonoraHermosilloSonoraMéxicoDepartamento de Nutrición Centro de Investigación en Alimentación y DesarrolloA.C.HermosilloSonoraMéxico

AIM： To study the histological and pancreatitis-associated protein mRnA accumulation changes of pancreas from acute phase of caerulin-induced pancreatitis to recuperation in rats. METHODS： Acute pancreatitis was induced by caerulein in male Wistar rats and followed up for 90 d by histological and mRnA analyses of pancreas. Pancreases were dissected at 0, 9, 24 h and 3, 5, 15, 30, 60, 90 d post-induction. Edema （E）, polymorphonuclear neutrophU （pIVln） infiltration, cytoplasmic vacuolization （V）, zymogen granule depletion （ZD） and acinar disorganization （AD） were microscopically evaluated. Accumulation of pancreatitis- associated protein （PAP） and l13A mRnAs were quantified by real-time PCR. RESUlTS： The main histological changes appeared at 9 h post-induction for PMn infiltration and cytoplasmic V, while at 24 h and 3 d for E and ZD, respectively. All the parameters were recovered after 5 d, except for ZD which delayed more than 30 d. The main AD was observed after 15 d and values returned to normal after 30 d. Similarly to histological changes, accumulation of the PAP mRnA was increased at 9 h with the highest accumulation at 24 h and differences disappeared after 5 d. COnClUSIOn： From the acute phase to recuperation of pancreatitis, regeneration and re-differentiation of pan- creas occur and PAP expression is exclusively an acute response of pancreatitis.

关键词： Acute pancreatitis Histological changes PAP mRnA l13A mRnA