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A Number Theoretic Analysis of the Enthalpy, Enthalpy Energy Density, Thermodynamic Volume, and the Equation of State of a Modified White Hole, and the Implications to the Quantum Vacuum Spacetime, Matter Creation and the Planck Frequency
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作者 Michele Nardelli Amos S. Kubeka Alizera Amani 《Journal of Modern Physics》 2024年第1期1-50,共50页
In this paper, we analyze the enthalpy, enthalpy energy density, thermodynamic volume, and the equation of state of a modified white hole. We obtain new possible mathematical connections with some sectors of Number Th... In this paper, we analyze the enthalpy, enthalpy energy density, thermodynamic volume, and the equation of state of a modified white hole. We obtain new possible mathematical connections with some sectors of Number Theory, Ramanujan Recurring Numbers, DN Constant and String Theory, that enable us to extract the quantum geometrical properties of these thermodynamic equations and the implication to the quantum vacuum spacetime geometry of our early universe as they act as the constraints to the nature of quantum gravity of the universe. 展开更多
关键词 Number Theory Ramanujan Recurring Numbers DN Constant String Theory Loop Quantum Gravity Matter Creation Enthalpy Energy Density Thermodynamic Volume ENTHALPY
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Extraterrestrial Life in the Thermosphere: Plasmas, UAP, Pre-Life, Fourth State of Matter
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作者 R. Joseph C. Impey +8 位作者 O. Planchon R. del Gaudio M. Abu Safa A. R. Sumanarathna E. Ansbro D. Duvall G. Bianciardi C. H. Gibson R. Schild 《Journal of Modern Physics》 2024年第3期322-376,共55页
“Plasmas” up to a kilometer in size and behaving similarly to multicellular organisms have been filmed on 10 separate NASA space shuttle missions, over 200 miles above Earth within the thermosphere. These self-illum... “Plasmas” up to a kilometer in size and behaving similarly to multicellular organisms have been filmed on 10 separate NASA space shuttle missions, over 200 miles above Earth within the thermosphere. These self-illuminated “plasmas” are attracted to and may “feed on” electromagnetic radiation. They have different morphologies: 1) cone, 2) cloud, 3) donut, 4) spherical-cylindrical;and have been filmed flying towards and descending from the thermosphere into thunderstorms;congregating by the hundreds and interacting with satellites generating electromagnetic activity;approaching the Space Shuttles. Computerized analysis of flight path trajectories documents these plasmas travel at different velocities from different directions and change their angle of trajectory making 45°, 90°, and 180° shifts and follow each other. They’ve been filmed accelerating, slowing down, stopping, congregating, engaging in “hunter-predatory” behavior and intersecting plasmas leaving a plasma dust trail in their wake. Similar life-like behaviors have been demonstrated by plasmas created experimentally. “Plasmas” may have been photographed in the 1940s by WWII pilots (identified as “Foo fighters”);repeatedly observed and filmed by astronauts and military pilots and classified as Unidentified Aerial—Anomalous Phenomenon. Plasmas are not biological but may represent a form of pre-life that via the incorporation of elements common in space, could result in the synthesis of RNA. Plasmas constitute a fourth state of matter, are attracted to electromagnetic activity, and when observed in the lower atmosphere likely account for many of the UFO-UAP sightings over the centuries. 展开更多
关键词 Extraterrestrials PLASMAS Dusty Plasmas EXTREMOPHILES Life in Space Abiogenesis Origins of Life RNA World
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Lipid lowering effects of iodothyronines:In vivo and in vitro studies on rat liver 被引量:3
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作者 Laura Vergani 《World Journal of Hepatology》 CAS 2014年第4期169-177,共9页
Non-alcoholic fatty liver disease(NAFLD) is emerging as one of the most common liver diseases,leading to the increasing interest for new therapeutic approaches for its treatment.NAFLD primarily depends on a hypercalor... Non-alcoholic fatty liver disease(NAFLD) is emerging as one of the most common liver diseases,leading to the increasing interest for new therapeutic approaches for its treatment.NAFLD primarily depends on a hypercaloric and/or unbalanced diet leading to overweight and obesity.The liver,in fact,plays a central role in lipid metabolism by importing free fatty acids from the blood and synthesizing,storing,oxidizing and exporting lipids.Furthermore,the liver is the target for the thyroid hormones,thyroxine(T4) and 3,3',5-triiodo-L-thyronine(T3),that stimulate the basal metabolic rate and lead to body weight loss.In the last decade,other iodothyronines have been shown to possess biological relevance and play some thyromimetic activities; in particular,3,5-diiodo-L-thyronine(T2) gained large interest.The global effect of iodothyronines on liver lipid metabolism results from the balance between direct and indirect actions on the hepatocyte,leading to stimulation of lipid synthesis,oxidation and autophagy.In this review,the results so far obtained on both in vivo and in vitro models of hepatosteatosis are summarized in order to obtain an updated picture of the lipid-lowering effects of iodothyronines on mammalian liver. 展开更多
关键词 Iodothyronines LIVER STEATOSIS LIPID metabolism Non-alcoholic FATTY LIVER disease HEPATOCYTES
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Hybrid Professionals and Academic Productivity: The Case of the University Polyclinic in Messina (Sicily)
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作者 Angela Alibrandi Lara Gitto +1 位作者 Michele Limosani Guido Noto 《Health》 2021年第1期1-15,共15页
The productivity of medical staff within a polyclinic is not an easy task due to the multiple activities that physicians must perform at the same time: not only healthcare for patients, but also academic activities, s... The productivity of medical staff within a polyclinic is not an easy task due to the multiple activities that physicians must perform at the same time: not only healthcare for patients, but also academic activities, such as scientific research and teaching. Hybrid professionals are healthcare professionals who have to play multiple roles, often not precisely identified. This analysis examines the case study of the University Polyclinic of Messina (Italy) where three university departments and 7 Dipartimenti di Attività Integrate (DAI) are distinguished and physicians (both professors and researchers) are called to reconcile multiple tasks. Given the distinction between university departments and DAIs, the aim of this contribution is to identify the organizational elements that prove to be predictors of scientific efficiency and productivity. To what extent does the inclusion in a DAI or within a university department affect individual incentives? A new dataset is built for the present research containing information on University Polyclinic of Messina physicians (full professors, associate professors, researchers). From the Scopus online database (<a href="https://www.scopus.com/home.uri">https://www.scopus.com/home.uri</a>) individual information relating to the number of publications, the number of citations, h-index was obtained. The latter is used to assess the quality of individual research;in order to evaluate the teaching activity, the number of hours dedicated to didactical activities is taken into account, together with the number of teaching hours required by one’s role. Information related to remuneration and the circumstance of carrying out intramural activities has also been included. A thorough statistical analysis is carried out and the individual groups (DAI and university departments) are compared through the Kruskal Wallis test. Estimating a Poisson Gamma mixture model highlights those variables that are significant predictors of scientific productivity. Attention paid to organizational methods should allow identifying the ideal setting for hybrid professionals to practice the medical profession, while carrying out managerial duties, without compromising the quality of teaching and research. An efficient solution could thus be proposed to the complex multi-objective optimization problem that healthcare professionals are called to answer. 展开更多
关键词 Hybrid Professionals University Departments DAI H-INDEX Poisson-Gamma Mixture Model
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Properties and Structural Studies of Multi-Wall Carbon Nanotubes-Phosphate Ester Hybrids
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作者 Marina Massaro Serena Riela +3 位作者 Giuseppe Cavallaro Maria Luisa Saladino Simonpietro Agnello Renato Noto 《International Journal of Organic Chemistry》 2013年第1期26-34,共9页
Long chain phosphate esters bearing at least one or two aryl groups have been synthesized and used for the preparation of stable multi-walled carbon nanotube (MWCNT) hybrids. The non-covalent interaction ester/MWCNT h... Long chain phosphate esters bearing at least one or two aryl groups have been synthesized and used for the preparation of stable multi-walled carbon nanotube (MWCNT) hybrids. The non-covalent interaction ester/MWCNT has been investigated by several techniques (SEM, UV-vis, 31P-NMR, RAMAN). The used phosphate ester derivatives demonstrated the ability to produce an excellent dispersion of MWCNT in CHCl3. The obtained dispersions showed a great stability from one to at least three weeks in the range of concentration considered. Thermal analysis showed an increase in the decomposition temperature for the hybrids with respect to pristine MWCNT. 展开更多
关键词 Multi-Wall Carbon NANOTUBES HYBRIDS Non COVALENT FUNCTIONALIZATION PHOSPHATE ESTERS
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Conversion of Existing Roundabouts into Turbo-Roundabouts: Case Studies from Real World
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作者 Orazio Giuffrè Marco Guerrieri Anna Granà 《Journal of Civil Engineering and Architecture》 2012年第8期953-962,共10页
关键词 现实世界 回旋 涡轮 案例 环岛 交叉路口 安全条件 事故风险
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The Interventions of Pietro da Cortona in the Crypt of Santa Maria in Via Lata in Rome, Studied through a Morphometric Three-Dimensional Survey
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作者 Lorenzo Pio Massimo Martino 《Open Journal of Civil Engineering》 2014年第2期92-101,共10页
Twenty years after the last archaeological researches and surveys, a new investigation has been carried out on the basement in the church of Santa Maria in Via Lata in Rome. The study has employed three-dimensional su... Twenty years after the last archaeological researches and surveys, a new investigation has been carried out on the basement in the church of Santa Maria in Via Lata in Rome. The study has employed three-dimensional surveys with laser scanning methodology and has focused both on archaeological and architectural issues. Indeed, the present layout of the basement derives from a XVII century remodelling of early Christian and medieval spaces planned by Pietro da Cortona. The architect gave a unique setting and composition to the underground spaces, different in shapes and building materials, thanks to the refinement of his baroque language. Though he worked in small spaces with static problems connected to the foundations and to the loads of the church rising above, and with poor lighting and extreme dampness, Pietro da Cortona put skilfully together “modern” elements with ancient or historical pre-existences. The study focuses on Berrettini’s design process through a three-dimensional analysis with CAD systems, starting from the new XVII century fa?ade and from the articulated distribution of routes that led to the intimate underground interiors. Metrical processing gave the possibility to improve the knowledge about room geometry and to confirm the interpretations put forward by major scholars such as Krautheimer and Cavazzi. 展开更多
关键词 Laser Scanner 3D Pietro DA Cortona History of Architecture SANTA Maria in VIA Lata ROME
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Corrosion Behaviour of Zr-Ag Alloys for Dental Implant Application
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作者 Francesco Rosalbino Daniele Macciò Giorgio Scavino 《Materials Sciences and Applications》 2023年第11期501-514,共14页
The electrochemical corrosion behaviour of three Zr-Ag alloys (Zr-1Ag, Zr-3Ag and Zr-5Ag) was investigated. Open circuit potential, linear potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) ... The electrochemical corrosion behaviour of three Zr-Ag alloys (Zr-1Ag, Zr-3Ag and Zr-5Ag) was investigated. Open circuit potential, linear potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques were employed in aerated artificial saliva (pH = 4.0) at 37°C. Silver alloying additions are found to be effective in enhancing the corrosion resistance of zirconium in artificial saliva environment. In fact, Zr-Ag alloys exhibit higher open circuit potentials, larger breakdown potentials and higher impedance values as compared to cp Zr. This behaviour can be ascribed to the formation of a thicker and more stable passive film with increasing compactness, able to provide better protection against the corrosion attack. 展开更多
关键词 Zr-Ag Alloys Corrosion Resistance Open Circuit Potential Potentiodynamic Polarization Curves Electrochemical Impedance Spectroscopy (EIS)
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The Stability of the Gauss-Laguerre Rule for Cauchy P.V. Integrals on the Half Line
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作者 Maria Rosaria Capobianco Giuliana Criscuolo 《American Journal of Computational Mathematics》 2023年第4期505-511,共7页
In this paper, the authors give a different and more precise analysis of the stability of the classical Gauss-Laguerre quadrature rule for the Cauchy P.V. integrals on the half line. Moreover, in order to obtain this ... In this paper, the authors give a different and more precise analysis of the stability of the classical Gauss-Laguerre quadrature rule for the Cauchy P.V. integrals on the half line. Moreover, in order to obtain this result they give some new estimates for the distance of the zeros of the Laguerre polynomials that can be useful also in other contests. 展开更多
关键词 Gauss Quadrature Exponential Weights Cauchy P.V. Integrals Stability
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贵州兴义中三叠世黔鱼龙属(爬行纲:鱼龙目)一新种 被引量:5
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作者 杨鹏飞 季承 +4 位作者 江大勇 Ryosuke Motani Andrea Tintori 孙元林 孙作玉 《北京大学学报(自然科学版)》 EI CAS CSCD 北大核心 2013年第6期1002-1008,共7页
描述产于贵州省兴义市乌沙镇中三叠统拉丁阶法郎组竹杆坡段的鱼龙类黔鱼龙属一新种——兴义黔鱼龙(Qianichthyosaurus xingyiensis sp.nov.),并厘定黔鱼龙属(Qianichthyosaurus)的鉴定特征:齿冠长度与头骨宽度之比略小于0.1;尺骨外边缘... 描述产于贵州省兴义市乌沙镇中三叠统拉丁阶法郎组竹杆坡段的鱼龙类黔鱼龙属一新种——兴义黔鱼龙(Qianichthyosaurus xingyiensis sp.nov.),并厘定黔鱼龙属(Qianichthyosaurus)的鉴定特征:齿冠长度与头骨宽度之比略小于0.1;尺骨外边缘呈片状或具凹缺;后肢近等或略长于前肢;胫骨外边缘呈片状或具凹缺。新种与Qianichthyosaurus属型种区别在于:吻部与头骨长度之比大于60%;肱骨远端桡骨关节面明显长于尺骨关节面;耻骨孔未闭合;腓骨后缘有一明显突起;坐骨亚三角形,缺少骨干。新种产出地层层位明显低于属型种的上三叠统卡尼阶法郎组瓦窑段,为目前发现的黔鱼龙属出现的最低层位。黔鱼龙属、贵州鱼龙属与海龙类安顺龙属在兴义和关岭均有发现,揭示中三叠世拉丁晚期的兴义动物群和晚三叠世卡尼期的关岭生物群可能有更紧密的关系。 展开更多
关键词 黔鱼龙 鱼龙 中三叠世 兴义动物群 贵州
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高组分稀磁半导体Cd_(1-x)Mn_xTe/CdTe超晶格的荧光谱研究 被引量:2
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作者 陈辰嘉 王学忠 +1 位作者 Bellani V Stella A 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2006年第3期396-398,共3页
报道用分子束外延(MBE)技术生长的x=0.4,0.8的高组分稀磁半导体Cd1-xMnxTe/CdTe超晶格低温和室温荧光谱研究结果。基态激子跃迁能级荧光谱实验结果显示高组分超晶格中具有高量子效率和高质量光发射。对激子能级随温度的变化进行了详细研... 报道用分子束外延(MBE)技术生长的x=0.4,0.8的高组分稀磁半导体Cd1-xMnxTe/CdTe超晶格低温和室温荧光谱研究结果。基态激子跃迁能级荧光谱实验结果显示高组分超晶格中具有高量子效率和高质量光发射。对激子能级随温度的变化进行了详细研究,给出激子跃迁能量的温度系数。激子能级线型的展宽随温度变化关系可用激子-纵向光学声子耦合模型解释。与光调制反射谱实验结果进行了比较。 展开更多
关键词 荧光谱 超晶格 稀磁半导体 光学声子 激子跃迁
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经鼻蝶内镜下鞍区手术后颅底多层重建技术 被引量:1
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作者 张合林 展如才 +3 位作者 Cappabianca. Paolo 齐再利 李玉强 Cavallo. Luigi M 《泰山医学院学报》 CAS 2009年第8期598-600,共3页
目的探讨内镜下鞍区手术后颅底多层重建技术的应用价值。方法收集病例12例,其中颅咽管瘤4例,鞍区脑膜瘤3例,巨大垂体瘤5例,均行内镜下经鼻蝶扩大入路肿瘤切除术,术中采用多层重建技术进行颅底重建。结果所有病例术后及随访3-6个月均未... 目的探讨内镜下鞍区手术后颅底多层重建技术的应用价值。方法收集病例12例,其中颅咽管瘤4例,鞍区脑膜瘤3例,巨大垂体瘤5例,均行内镜下经鼻蝶扩大入路肿瘤切除术,术中采用多层重建技术进行颅底重建。结果所有病例术后及随访3-6个月均未出现脑脊液漏和张力性气颅等并发症。结论内镜下经鼻蝶鞍区手术后颅底多层重建技术是一种简单安全有效的方法。 展开更多
关键词 内镜 经鼻蝶扩大入路 颅底 重建
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Treatment of gastric cancer 被引量:117
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作者 Michele Orditura Gennaro Galizia +10 位作者 Vincenzo Sforza Valentina Gambardella Alessio Fabozzi Maria Maddalena Laterza Francesca Andreozzi Jole Ventriglia Beatrice Savastano Andrea Mabilia Eva Lieto Fortunato Ciardiello Ferdinando De Vita 《World Journal of Gastroenterology》 SCIE CAS 2014年第7期1635-1649,共15页
The authors focused on the current surgical treatment of resectable gastric cancer,and significance of periand post-operative chemo or chemoradiation.Gastric cancer is the 4thmost commonly diagnosed cancer and the sec... The authors focused on the current surgical treatment of resectable gastric cancer,and significance of periand post-operative chemo or chemoradiation.Gastric cancer is the 4thmost commonly diagnosed cancer and the second leading cause of cancer death worldwide.Surgery remains the only curative therapy,while perioperative and adjuvant chemotherapy,as well as chemoradiation,can improve outcome of resectable gastric cancer with extended lymph node dissection.More than half of radically resected gastric cancer patients relapse locally or with distant metastases,or receive the diagnosis of gastric cancer when tumor is disseminated;therefore,median survival rarely exceeds12 mo,and 5-years survival is less than 10%.Cisplatin and fluoropyrimidine-based chemotherapy,with addition of trastuzumab in human epidermal growth factor receptor 2 positive patients,is the widely used treatment in stageⅣpatients fit for chemotherapy.Recent evidence supports the use of second-line chemotherapy after progression in patients with good performance 展开更多
关键词 GASTRIC CANCER SURGERY RADIOTHERAPY ADJUVANT chemo
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Non-invasive assessment of liver fibrosis in chronic hepatitis B 被引量:20
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作者 Federica Branchi Clara Benedetta Conti +3 位作者 Alessandra Baccarin Pietro Lampertico Dario Conte Mirella Fraquelli 《World Journal of Gastroenterology》 SCIE CAS 2014年第40期14568-14580,共13页
The goal of this review is to provide a comprehensive picture of the role,clinical applications and future perspectives of the most widely used non-invasive techniques for the evaluation of hepatitis B virus(HBV)infec... The goal of this review is to provide a comprehensive picture of the role,clinical applications and future perspectives of the most widely used non-invasive techniques for the evaluation of hepatitis B virus(HBV)infection.During the past decade many non-invasive methods have been developed to reduce the need for liver biopsy in staging fibrosis and to overcome whenever possible its limitations,mainly:invasiveness,costs,low reproducibility,poor acceptance by patients.Elastographic techniques conceived to assess liver stiffness,in particular transient elastography,and the most commonly used biological markers will be assessed against their respective role and limitations in staging hepatic fibrosis.Recent evidence highlights that both liver stiffness and some bio-chemical markers correlatewith survival and major clinical end-points such as liver decompensation,development of hepatocellular carcinoma and portal hypertension.Thus the non-invasive techniques here discussed can play a major role in the management of patients with chronic HBV-related hepatitis.Given their prognostic value,transient elastography and some bio-chemical markers can be used to better categorize patients with advanced fibrosis and cirrhosis and assign them to different classes of risk for clinically relevant outcomes.Very recent data indicates that the combined measurements of liver and spleen stiffness enable the reliable prediction of portal hypertension and esophageal varices development. 展开更多
关键词 Liver FIBROSIS CIRRHOSIS HEPATITIS B VIRUS Transie
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Diagnostic and therapeutic implications of the association between ferritin level and severity of nonalcoholic fatty liver disease 被引量:15
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作者 Luca Valenti Paola Dongiovanni Silvia Fargion 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第29期3782-3786,共5页
Nonalcoholic fatty liver disease(NAFLD),defined by excessive liver fat deposition related to the metabolic syndrome,is a leading cause of progressive liver disease,for which accurate non-invasive staging systems and e... Nonalcoholic fatty liver disease(NAFLD),defined by excessive liver fat deposition related to the metabolic syndrome,is a leading cause of progressive liver disease,for which accurate non-invasive staging systems and effective treatments are still lacking.Evidence has shown that increased ferritin levels are associated with the metabolic insulin resistance syndrome,and higher hepatic iron and fat content.Hyperferritinemia and iron stores have been associated with the severity of liver damage in NAFLD,and iron depletion reduced insulin resistance and liver enzymes.Recently,Kowdley et al demonstrated in a multicenter study in 628 adult patients with NAFLD from the NAFLD-clinical research network database with central re-evaluation of liver histology and iron staining that the increased serum ferritin level is an independent predictor of liver damage in patients with NAFLD,and is useful to identify NAFLD patients at risk of non-alcoholic steatohepatitis and advanced fibrosis.These data indicate that incorporation of serum ferritin level may improve the performance of noninvasive scoring of liver damage in patients with NAFLD,and that iron depletion still represents an attractive therapeutic target to prevent the progression of liver damage in these patients. 展开更多
关键词 脂肪含量 蛋白水平 严重程度 酒精性 血清铁 肝病 治疗 肝功能损害
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Diabetic foot syndrome:Immune-inflammatory features as possible cardiovascular markers in diabetes 被引量:37
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作者 Antonino Tuttolomondo Carlo Maida Antonio Pinto 《World Journal of Orthopedics》 2015年第1期62-76,共15页
Diabetic foot ulcerations have been extensively reported as vascular complications of diabetes mellitus associated with a high degree of morbidity and mortality. Diabetic foot syndrome(DFS), as defined by the World He... Diabetic foot ulcerations have been extensively reported as vascular complications of diabetes mellitus associated with a high degree of morbidity and mortality. Diabetic foot syndrome(DFS), as defined by the World Health Organization, is an "ulceration of the foot(distally from the ankle and including the ankle) associated with neuropathy and different grades of ischemia and infection". Pathogenic events able to cause diabetic foot ulcers are multifactorial.Among the commonest causes of this pathogenic pathway it's possible to consider peripheral neuropathy, foot deformity, abnormal foot pressures, abnormal joint mobility, trauma, peripheral artery disease. Several studies reported how diabetic patients show a higher mortality rate compared to patients without diabetes and in particular these studies under filled how cardiovascular mortality and morbidity is 2-4 times higher among patients affected by type 2 diabetes mellitus. This higher degree of cardiovascular morbidity has been explained as due to the observed higher prevalence of major cardiovascular risk factor, of asymptomatic findings of cardiovascular diseases, and of prevalence and incidence of cardiovascular and cerebrovascular events in diabetic patients with foot complications. In diabetes a fundamental pathogenic pathway of most of vascular complications has been reported as linked to a complex interplay of inflammatory, metabolic and procoagulant variables. These pathogenetic aspects have a direct interplay with an insulin resistance, subsequent obesity, diabetes, hypertension, prothrombotic state and blood lipid disorder. Involvement of inflammatory markers such as IL-6 plasma levels and resistin in diabetic subjects as reported by Tuttolomondo et al confirmed the pathogenetic issue of the a "adipo-vascular" axis that may contribute to cardiovascular risk in patients with type 2 diabetes. This "adipo-vascular axis" in patients with type 2 diabetes has been reported as characterized by lower plasma levels of adiponectin and higher plasma levels of interleukin-6 thus linking foot ulcers pathogenesis to microvascular and inflammatory events. The purpose of this review is to highlight the immune inflammatory features of DFS and its possible role as a marker of cardiovascular risk in diabetes patients and to focus the management of major complications related to diabetes such as infections and peripheral arteriopathy. 展开更多
关键词 DIABETIC FOOT syndrome Inflammation CYTOKINES CARDIOVASCULAR risk MARKER
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Hepatocellular carcinoma in nonalcoholic fatty liver: Role of environmental and genetic factors 被引量:38
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作者 Paola Dongiovanni Stefano Romeo Luca Valenti 《World Journal of Gastroenterology》 SCIE CAS 2014年第36期12945-12955,共11页
Hepatocellular carcinoma(HCC) is the fourth cause of cancer related mortality, and its incidence is rapidly increasing. Viral hepatitis, alcohol abuse, and exposure to hepatotoxins are major risk factors, but nonalcoh... Hepatocellular carcinoma(HCC) is the fourth cause of cancer related mortality, and its incidence is rapidly increasing. Viral hepatitis, alcohol abuse, and exposure to hepatotoxins are major risk factors, but nonalcoholic fatty liver disease(NAFLD) associated with obesity, insulin resistance, and type 2 diabetes, is an increasingly recognized trigger, especially in developed countries. Older age, severity of insulin resistance and diabetes, and iron overload have been reported to predispose to HCC in this context. Remarkably, HCCs have been reported in non-cirrhotic livers in a higher proportion of cases in NAFLD patients than in other etiologies. Inherited factors have also been implicated to explain the different individual susceptibility to develop HCC, and their role seems magnified in fatty liver, where only a minority of affected subjects progresses to cancer. In particular, the common I148 M variant of the PNPLA3 gene influencing hepatic lipid metabolism influences HCC risk independently of its effect on the progression of liver fibrosis. Recently, rare loss-of-function mutations in Apolipoprotein B resulting in very low density lipoproteins hepatic retention and in Telomerase reverse transcriptase influencing cellular senescence have also been linked to HCC in NAFLD. Indeed, hepatic stellate cells senescence has been suggested to bridge tissue aging with alterations of the intestinal microbiota in the pathogenesis of obesity-related HCC. A deeper understanding of the mechanisms mediating hepatic carcinogenesis during insulin resistance, and the identification of its genetic determinants will hopefully provide new diagnostic and therapeutic tools. 展开更多
关键词 NONALCOHOLIC FATTY LIVER disease STEATOSIS Hepatoc
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PNPLA3 I148M polymorphism and progressive liver disease 被引量:17
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作者 Paola Dongiovanni Benedetta Donati +4 位作者 Roberta Fares Rosa Lombardi Rosellina Margherita Mancina Stefano Romeo Luca Valenti 《World Journal of Gastroenterology》 SCIE CAS 2013年第41期6969-6978,共10页
The 148 Isoleucine to Methionine protein variant(I148M)of patatin-like phospholipase domain-containing 3(PNPLA3),a protein is expressed in the liver and is involved in lipid metabolism,has recently been identified as ... The 148 Isoleucine to Methionine protein variant(I148M)of patatin-like phospholipase domain-containing 3(PNPLA3),a protein is expressed in the liver and is involved in lipid metabolism,has recently been identified as a major determinant of liver fat content.Several studies confirmed that the I148M variant predisposes towards the full spectrum of liver damage associated with fatty liver:from simple steatosis to steatohepatitis and progressive fibrosis.Furthermore,the I148M variant represents a major determinant of progression of alcohol related steatohepatitis to cirrhosis,and to influence fibrogenesis and related clinical outcomes in chronic hepatitis C virus hepatitis,and possibly chronic hepatitis B virus hepatitis,hereditary hemochromatosis and primary sclerosing cholangitis.All in all,studies suggest that the I148M polymorphism may represent a general modifier of fibrogenesis in liver diseases.Remarkably,the effect of the I148M variant on fibrosis was independent of that on hepatic steatosis and inflammation,suggesting that it may affect both the quantity and quality of hepatic lipids and the biology of non-parenchymal liver cells besides hepatocytes,directly promoting fibrogenesis.Therefore,PNPLA3 is a key player in liver disease progression.Assessment of the I148M polymorphism will possibly inform clinical practice in the future,whereas the determination of the effect of the 148M variant will reveal mechanisms involved in hepatic fibrogenesis. 展开更多
关键词 Alcoholic LIVER DISEASE Chronic HEPATITIS C virus HEPATITIS FIBROGENESIS Genetics Hepatocellular carcinoma LIVER DISEASE Nonalcoholic fatty LIVER DISEASE Patatin-like PHOSPHOLIPASE domain-containing 3 Single nucleotide POLYMORPHISM Steatosis
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Methodological issues in the study of intestinal microbiota in irritable bowel syndrome 被引量:10
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作者 Valentina Taverniti Simone Guglielmetti 《World Journal of Gastroenterology》 SCIE CAS 2014年第27期8821-8836,共16页
Irritable bowel syndrome(IBS) is an intestinal functional disorder with the highest prevalence in the industrialized world. The intestinal microbiota(IM) plays a role in the pathogenesis of IBS and is not merely a con... Irritable bowel syndrome(IBS) is an intestinal functional disorder with the highest prevalence in the industrialized world. The intestinal microbiota(IM) plays a role in the pathogenesis of IBS and is not merely a consequence of this disorder. Previous research efforts have not revealed unequivocal microbiological signatures of IBS, and the experimental results are contradictory. The experimental methodologies adopted to investigate the complex intestinal ecosystem drastically impact the quality and significance of the results. Therefore, to consider the methodological aspects of the research on IM in IBS, we reviewed 29 relevant original research articles identified through a PubMed search using three combinations of keywords: "irritable bowel syndrome + microflora", "irritable bowel syndrome + microbiota" and "irritable bowel syndrome + microbiome". For each study, we reviewed the quality and significance of the scientific evidence obtained with respect to the experimental method adopted. The data obtained from each study were compared with all considered publications to identify potential inconsistencies and explain contradictory results. The analytical revision of the studies referenced in the present review has contributed to the identification of microbial groups whose relative abundance significantly alters IBS, suggesting that these microbial groups could be IM signatures for this syndrome. The identification of microbial biomarkers in the IM can be advantageous for the development of new diagnostic tools and novel therapeutic strategies for the treatment of different subtypes of IBS. 展开更多
关键词 INTESTINAL DYSFUNCTION IRRITABLE BOWEL SYNDROME In
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Therapeutic and clinical aspects of portal vein thrombosis in patients with cirrhosis 被引量:13
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作者 Massimo Primignani Giulia Tosetti Vincenzo La Mura 《World Journal of Hepatology》 CAS 2015年第29期2906-2912,共7页
Portal vein thrombosis(PVT) is a frequent complication in cirrhosis, particularly in advanced stages of the disease. As for general venous thromboembolism, risk factors for PVT are slow blood flow, vessel wall damage ... Portal vein thrombosis(PVT) is a frequent complication in cirrhosis, particularly in advanced stages of the disease. As for general venous thromboembolism, risk factors for PVT are slow blood flow, vessel wall damage and hypercoagulability, all features of advanced cirrhosis. Actually, the old dogma of a hemorrhagic tendency in cirrhosis has been challenged by new laboratory tools and the clinical evidence that venous thrombosis also occurs in cirrhosis. The impaired hepatic synthesis of both pro- and anticoagulants leads to a rebalanced hemostasis, more liable to be tipped towards thrombosis or even bleeding. Conventional anticoagulant drugs(low molecular weight heparin or vitamin K antagonists) may be used in cirrhosis patients with PVT, particularly in those eligible for liver transplantation, to prevent thrombosis progression thus permitting/facilitating liver transplant. However, several doubts exist on the level of anticoagulation achieved as estimated by coagulation tests, on the efficacy of treatment monitoring and on the correct timing for discontinuation in non-transplant candidates, while in transplant candidates there is expert consensus on continuing anticoagulation until transplantation. The recent introduction of direct acting oral anticoagulant drugs(DOACs) in other clinical settings generates much interest on their possible application in patients with cirrhosis and PVT. However, DOACs were not evaluated yet in patients with liver disease and cannot be recommended for the present time. 展开更多
关键词 PORTAL VEIN THROMBOSIS COAGULOPATHY Hypercoagulopathy Direct ACTING oral anticoagulantdrugs CIRRHOSIS
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