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Impact of comorbidities on the severity of chronic hepatitis B at presentation

World Journal of Gastroenterology 2012年第14期18卷 1616-1621页

作者： Evangelista Sagnelli Tommaso Stroffolini alfonso Mele Michele Imparato Caterina Sagnelli Nicola Coppola Piero Luigi Almasio Department of Public Medicine Section of Infectious DiseasesSecond University of Naples80132 NaplesItaly Department of Infectious and Tropical Diseases Policlinico Umberto I00161 RomeItaly Laboratory of Epidemiology Clinical Epidemiology UnitIstituto Superiore di Sanità00161 RomeItaly Department of Clinical and Experimental Medicine and Surgery "F.Magrassi e A.Lanzara" Second University of Naples80132 NaplesItaly Gastroenterology Unit University of Palermo90127 PalermoItaly

AIM:To evaluate the clinical relevance of each cofactor on clinical presentation of chronic hepatitis ***:Out of 1366 hepatitis B surface antigen(HBsAg) positive subjects consecutively observed in 79 Italian hospitals,53(4.3%) showed as the only cofactor hepatitis D virus(HDV) infection [hepatitis B virus(HBV)/HDV group],130(9.5%) hepatitis C virus(HCV)(group HBV/HCV),6(0.4%) human immunodeficiencyvirus(HIV)(group HBV/HIV),138(10.2%) alcohol abuse(group HBV/alcohol);109(8.0%) subjects had at least two cofactors and 924 were in the cofactor-free(CF) ***:Compared with patients in group CF those in group HBV/alcohol were older and more frequently had cirrhosis(P < 0.001),those in group HBV/HDV were younger(P < 0.001),more frequently resided in the south of the country and had cirrhosis(P <0.001),those in group HBV/HCV were older(P < 0.001) and more frequently had cirrhosis(P < 0.001).These cofactors were all independent predictors of liver cirrhosis in HBsAg positive *** analysis showed that an older age [odds ratio(OR) 1.06,95% CI:1.05-1.08],alcohol abuse with more than 8 drinks daily(OR 2.89,95% CI:1.81-4.62) and anti-HDV positivity(OR 3.48,95% CI:2.16-5.58) are all independently associated with liver *** association was found also for anti-HCV positivity in univariate analysis,but it was no longer associated(OR 1.23,95% CI:0.84-1.80) at multivariate ***:Older age,HDV infection and alcohol abuse are the major determinants of severe liver disease in chronic HBV infection,while HCV replication plays a lesser role in the severity of hepatic damage.

关键词：慢性乙型肝炎合并症乙肝表面抗原乙型肝炎病毒丙型肝炎病毒病毒感染多元统计分析临床意义

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Natural compounds and extracts from Mexican medicinal plants with anti-leishmaniasis activity: An update

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Asian Pacific Journal of Tropical Medicine 2017年第12期10卷 1105-1110页

作者： Gabriel alfonso Gutiérrez-Rebolledo Susan Drier-Jonas María Adelina Jiménez-Arellanes Unidad de Investigación Médica en Farmacología Hospital de EspecialidadesCentro Médico Nacional Siglo XXIInstituto Mexicano del Seguro SocialAv. Cuauhtémoc 330Col. DoctoresDelg. Cuauhtémoc06720 Ciudad de MéxicoMexico

Leishmaniasis is considered as an emerging, uncontrolled disease and is endemic in 98 countries. Annually, about 2 million cases of cutaneous and 500000 cases of visceraltype leishmaniasis are recorded and 60000 persons died from the disease. In Mexico,cutaneous leishmaniasis is known as chiclero's ulcer and is reported in 22 states, it is considered as a health problem. For its treatment, pentavalent antimonial drugs are administered. These drugs cause severe side effects, are costly. Drug-resistant cases have been reported and have been developing for over 70 years. One alternative to the drugs that are currently available is to find active molecules in medicinal plants. Dihydrocorynantheine, corynantheine and corynantheidine are active against Leishmania major,while harmane, pleiocarpin, buchtienin, luteolin and quercetin are active against Leishmania donovani. In Mexico, about 20 medicinal plants have been evaluated against Leishmania mexicana, among which the most active are Tridax procumbens, Lonchocarpus xuul and Pentalinon andrieuxii. From these plants, active compounds with IC_(50)≤30 mg/mL or m M have been isolated, such as 3(S)-16,17-didehydrofalcarinol or Oxylipin, cholestra-4,20,24-trien-3-one or pentalinosterol, 24-methylcholest-4-24(28)-dien-3-one, cholest-4-en-3-one, 6,7-dihydroneridie-none, neridienone, cholest-5,20,24-trien-3β-ol, and isocordoin. Today, only pentalinonsterol has been synthesized and assayed in the visceral leishmaniasis experimental model using BALB/c mice infected with Leishmania donovani. Liposome formulation of this compound administered by intravenous route at 2.5 mg/kg showed a significant reduction of parasite load in mouse liver and spleen.

关键词： Active extracts Leishmaniasis Antileishmanicidal activity Natural compounds Mexican medicinal plants

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Planetary Gear Profile Modification Design Based on Load Sharing Modelling

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Chinese Journal of Mechanical Engineering 2015年第4期28卷 810-820页

作者： IGLESIAS Miguel FERNáNDEZ DEL RINCóN alfonso DE-JUAN Ana Magdalena GARCIA Pablo DIEZ Alberto VIADERO Fernando Mechanical Engineering Research Group University of Cantabria

In order to satisfy the increasing demand on high performance planetary transmissions, an important line of research is focused on the understanding of some of the underlying phenomena involved in this mechanical system. Through the development of models capable of reproduce the system behavior, research in this area contributes to improve gear transmission insight, helping developing better maintenance practices and more efficient design processes. A planetary gear model used for the design of profile modifications ratio based on the levelling of the load sharing ratio is presented. The gear profile geometry definition, following a vectorial approach that mimics the real cutting process of gears, is thoroughly described. Teeth undercutting and hypotrochoid definition are implicitly considered, and a procedure for the incorporation of a rounding arc at the tooth tip in order to deal with corner contacts is described. A procedure for the modeling of profile deviations is presented, which can be used for the introduction of both manufacturing errors and designed profile modifications. An easy and flexible implementation of the profile deviation within the planetary model is accomplished based on the geometric overlapping. The contact force calculation and dynamic implementation used in the model are also introduced, and parameters from a real transmission for agricultural applications are presented for the application example. A set of reliefs is designed based on the levelling of the load sharing ratio for the example transmission, and finally some other important dynamic factors of the transmission are analyzed to assess the changes in the dynamic behavior with respect to the non-modified case. Thus, the main innovative aspect of the proposed planetary transmission model is the capacity of providing a simulated load sharing ratio which serves as design variable for the calculation of the tooth profile modifications.

关键词： transmission planetary gear load sharing relief profile modification

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Analysis of heterogeneous characteristics in a geothermal area with low permeability and high temperature

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Geoscience Frontiers 2017年第5期8卷 1039-1050页

作者： alfonso Aragón-Aguilar Georgina Izquierdo-Montalvo Siomara López-Blanco Víctor Arellano-Gómez Instituto Nacional de Electricidad y Energías Limpias Reforma 113 Col.Palmira Cuernavaca Morelos CP 62490 Mexico

An analytical methodology for reservoir characterization was applied in the central and southwestern zones of Los Humeros geothermal field(LHGF). This study involves analysis of temperature, pressure,enthalpy and permeability in wells and their distribution along the area. The wells located in the central western side of the geothermal field are productive, whereas those located at the central-eastern side are non-productive. Through temperature profiles, determined at steady state in the analyzed wells, it was observed that at bottom conditions(approximately 2300 m depth), temperatures vary between 280 and360℃. The temperatures are higher at the eastern side of central zone of LHGF. A review of transient pressure tests, laboratory measurements of core samples, and correlation of circulation losses during drilling suggest that permeability of the formation is low. The enthalpy behavior in productive wells shows a tendency of increase in the steam fraction. It was found that productivity behavior has inverse relation with permeability of rock formation. Further, it is observed that an imbalance exists between exploitation and recharge. It is concluded from the results that the wells located at central-eastern area have low permeability and high temperature, which indicates possibility of heat storage.

关键词： Los Humeros geothermal field Reservoir performance Hot rock Enthalpy Permeability Recharge

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Neuroscience Bulletin 2015年第3期31卷 317-330页

作者： Fernando Marmolejo-Ramos Kim Hellemans Amy Comeau Adam Heenan Andrew Faulkner alfonso Abizaid Amedeo D'Angiulli Department of Psychology Stockholm University Department of Neuroscience Carleton University Department of Psychology Queens UniversityKingston Institute of Interdisciplinary Studies Carleton University

Although food and affective pictures share similar emotional and motivational characteristics, the relationship between the neuronal responses to these stimuli is unclear. Particularly, it is not known whether perceiving and imagining food and affective stimuli elicit similar event-related potential （ERP） patterns. In this study, two ERP correlates, the early posterior negativity （EPN） and the late positive potential （LPP） for perceived and imagined emotional and food photographs were investigated. Thirteen healthy volunteers were exposed to a set of food photos, as well as unpleasant, pleasant, and neutral photos from the International Affective Picture System. In each trial, participants were first asked to view a photo （perception condition）, and then to create a visual mental image of it and to rate its vividness （imagery condition）. The results showed that during perception, brain regions corresponding to sensorimotor and parietal motivational （defensive and appetitive） systems were activated to different extents, producing a graded pattern of EPN and LPP responses specific to the photo content - more prominent for unpleasant than pleasant and food content. Also, an EPN signature occurred in both conditions for unpleasant content, suggesting that, compared to food or pleasant content, unpleasant content may be attended to more intensely during perception and may be represented more distinctly during imagery. Finally, compared to LLP activation during perception, as well as imagery and perception of all other content, LPP activation was significantly reduced during imagery of unpleasant photos, suggesting inhibition of unwanted memories. Results are framed within a neurocognitive working model of embodied emotions.

关键词： food emotion perception mentaimagery ERP EPN LPP vividness InternationaAffective Picture System embodiment

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Effects of hydrogen charging and deformation on tensile properties of a multi-component alloy for nuclear applications

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Tungsten 2022年第3期4卷 212-218页

作者： Te Zhu Zhi-Hong Zhong Koichi Sato Ya-Min Song Feng-Jiao Ye Qian-Qian Wang Ye Dong Peng Zhang Run-Sheng Yu Bao-Yi Wang alfonso H.W.Ngan Xing-Zhong Cao Qiu Xu Department of Mechanical Engineering The University of Hong KongPokfulam RoadHong KongChina Institute of High Energy Physics Chinese Academy of SciencesBeijing100049China Institute for Integrated Radiation and Nuclear Science Kyoto UniversityOsaka5900494Japan School of Materials Science and Engineering Hefei University of TechnologyHefei230009China Graduate School of Science and Engineering Kagoshima UniversityKagoshima8900065Japan

In this study,the influence of hydrogen charging and deformation on the tensile behavior of a 60Fe-12Cr-10Mn-15Cu-3Mo multi-component alloy was investigated using electron microscopy and positron annihilation lifetime *** results show that hydrogen-induced vacancy clusters found in the electrochemically charged hydrogen specimens are responsible for crack *** ingress to the microstructure,hydrogen promotes the formation of cell-structured dislocations that are beneficial for the improvement of tensile *** addition,hydrogen embrittlement can be mitigated by dislocations that can hinder hydrogen mobility in the deformed specimens.

关键词： Hydrogen embrittlement Dislocation cell Multi-component alloys

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3种地中海橡树在叶脉和气孔性状上的个体发育性变化及其与叶片经济性状的关系

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Journal of Plant Ecology 2021年第6期14卷 1090-1104页

作者： Sonia Mediavilla Ignacio Martin alfonso Escudero Area de Ecologia Facultad de BiologiaUniversidad de SalamancaCampus Miguel de UnamunoSalamanca 37007Spain Dpto.de Botanica y Fisiologia Vegetal Facultad de BiologiaUniversidad de SalamancaCampus Miguel de UnamunoSalamanca 37007Spain

我们比较了3个地中海栎属(Quercus)树种幼苗和成龄树的叶脉和气孔性状。之前的研究表明,幼苗的气体交换率往往比成龄树的要高。我们的研究目标是确认叶脉和气孔的性状在整个植物个体发育过程中是否会随着气体交换率的变化而同步改变。... 详细信息

我们比较了3个地中海栎属(Quercus)树种幼苗和成龄树的叶脉和气孔性状。之前的研究表明,幼苗的气体交换率往往比成龄树的要高。我们的研究目标是确认叶脉和气孔的性状在整个植物个体发育过程中是否会随着气体交换率的变化而同步改变。我们提出了以下两个备选假设:幼苗比成龄树有着更高的叶脉和气孔密度(假设1);幼苗在维管组织上的投资更少,从而降低了建设成本(假设2)。本研究是在西班牙中西部进行的,我们对每个树种不同生长阶段的植株随机采集了10个样本。我们测量了气孔和叶脉的平均性状(单位叶面积里的气孔大小和数量、叶脉密度、叶脉体积、叶脉到表皮的距离),比叶质量和叶片厚度。研究结果表明,细脉密度和单位面积叶脉体积随着树龄的增加而增加,这似乎与气体交换率方面的个体发育趋势不一致。这种差异支持了我们的假设2,说明植株在幼苗阶段减少对维管组织的投资以最大限度地提高生长速度是其当务之急。幼苗叶片中较大的叶脉间距可以由叶脉到表皮的较短距离所补偿。因此,薄叶片可能是幼苗的一个必要性状,它可以让水分沿较短路径输送到蒸发点,而无需对高成本的维管组织进行大量投资。

关键词：叶脉序叶寿命植物个体发育变化栎属(Quercus)物种气孔特征

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Effect of Tantalum Doping on TiO<sub>2</sub>Nanotube Arrays for Water-Splitting

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Modern Research in Catalysis 2015年第1期4卷 1-12页

作者： alfonso Pozio ENEA C.R. Casaccia Via Anguillarese 301 00123 S. Maria di Galeria Rome Italy

This work is intended to define a new possible methodology for TiO2 doping through the use of electrochemical deposition of tantalum directly on the titanium nanotubes obtained by a previous galvanostatic anodization treatment in an ethylene glycol solution. This method does not seem to cause any influence on the nanotube structure, showing final products with news and interesting features with respect to the unmodified sample. Together with a decrease in the band gap and flat band potential of the TiO2 nanotubes, the tantalum doped specimen reports an increase of the photo conversion efficiency under UV light.

关键词： Nanotube TiO2 Water Photoelectrolysis Photoelectrode OER

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Inventory and Geometrical Changes in Small Glaciers Covering Three Northern Patagonian Summits Using Remote Sensing and GIS Techniques

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Journal of Mountain Science 2010年第1期7卷 26-35页

作者： alfonso Fernández José Araos Jorge Marín Department of Geography Faculty of Architecture Urbanism and Geography Universidad de Concepción Centro de Estudios Avanzados en Zonas áridas (Ceaza)

In the last few decades, a large quantity of research has been performed to elucidate the current behavior of glaciers in southern Chile, especially with respect to the volumetric changes in the outlets of the Northern and Southern Patagonian Icefields (NPI and SPI, respectively). Calculations have shown a generalized thinning and withdrawal, which greatly contributes to the increase in sea level attributed to the ice melt from non-polar glaciers. However, these icefields are surrounded by many small icecaps, which have yet to be studied in detail. A precise estimation of the volume of ice located in these mountain chains could provide new information with respect to this area's exact contribution to the increase in sea level. Thus, this study presents an inventory of relatively small Northern Patagonian glaciers in the surrounding of the three summits: Mount Queulat, and the Macá and Hudson volcanoes. The study used remote sensing techniques in a GIS environment to determine the margins, surface areas, thickness changes and hypsometry for the glaciated zones. Landsat images from different dates were analyzed using standard band ratio and screen delineation techniques. Additionally, digital elevation models from different dates were compared using map algebra, calculating thickness changes. Based on the results, we propose that there are important volumetric changes in the glaciers studied, which could be explained by precipitation trends in a general context, and an influence of the glaciers' sizes in some local response. Therefore, we suggest the exact contribution of the Patagonia to the increase in sea level corresponds to a regional pattern rather than just the behavior of a single ice field.

关键词：冰川变化遥感技术 GIS技术库存地理信息系统海平面上升塔几何

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Genetic variants involved in gallstone formation and capsaicin metabolism,and the risk of gallbladder cancer in Chilean women

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World Journal of Gastroenterology 2010年第3期16卷 372-378页

作者： Sergio Báez Yasuo Tsuchiya alfonso Calvo Martha Pruyas Kazutoshi Nakamura Chikako Kiyohara Mari Oyama Masaharu Yamamoto Department of Surgery Sótero del Río Hospital Department of Community Preventive Medicine Niigata University Graduate School of Medical and Dental Sciences Department of Anatomic Pathology Sótero del Río Hospital Department of Preventive Medicine Graduate School of Medical SciencesKyushu University Faculty of Health Sciences Niigata University of Health and Welfare

AIM:To determine the effects of genetic variants associated with gallstone formation and capsaicin (a pungent component of chili pepper) metabolism on the risk of gallbladder cancer (GBC).METHODS: A total of 57 patients with GBC, 119 patients with gallstones, and 70 controls were enrolled in this study. DNA was extracted from their blood or paraffi n block sample using standard commercial kits. The statuses of the genetic variants were assayed using Taqman SNP Genotyping Assays or Custom Taqman SNP Genotyping ***:The non-ancestral T/T genotype of apolipoprotein B rs693 polymorphism was associated with a decreased risk of GBC (OR:0.14,95% CI:0.03-0.63). The T/T genotype of cholesteryl ester transfer protein (CETP) rs708272 polymorphism was associated with an increased risk of GBC (OR:5.04,95% CI:1.43-17.8).CONCLUSION: Genetic variants involved in gallstone formation such as the apolipoprotein B rs693 and CETP rs 708272 polymorphisms may be related to the risk of developing GBC in Chilean women.

关键词： Genetic risk factor Gallbladder cancer Gallstone Genetic polymorphism Apolipoprotein B Cholesteryl ester transfer protein

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