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Risk factors and classifications of hilar cholangiocarcinoma

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World Journal of Gastrointestinal Oncology 2013年第7期5卷 132-138页

作者： Miguel Angel Suarez-Munoz Jose luis Fernandez-Aguilar Belinda Sanchez-Perez Jose Antonio Perez-Daga Beatriz Garcia-Albiach Ysabel Pulido-roa Naiara Marin-Camero Julio Santoyo-Santoyo General Digestive and Transplantation Surgery Service HPB and Liver Transplant UnitUniversity Hospital Carlos Haya29010 MalagaSpain

Cholangiocarcinoma is the second most common primary malignant tumor of the *** cholangiocarcinoma or Klatskin tumor represents more than 50% of all biliary tract cholangiocarcinomas.A wide range of risk factors have been identified among patients with Perihilar cholangiocarcinoma including advanced age,male gender,primary sclerosing cholangitis,choledochal cysts,cholelithiasis,cholecystitis,parasitic infection(Opisthorchis viverrini and Clonorchis sinensis),inflammatory bowel disease,alcoholic cirrhosis,nonalcoholic cirrhosis,chronic pancreatitis and metabolic *** classifications have been used to describe the pathologic and radiologic appearance of *** three systems most commonly used to evaluate Perihilar cholangiocarcinoma are the Bismuth-Corlette(BC) system,the Memorial Sloan-Kettering Cancer Center and the TNM *** BC classification provides preoperative assessment of local *** Memorial Sloan-Kettering cancer center proposes a staging system according to three factors related to local tumor extent:the location and extent of bile duct involvement,the presence or absence of portal venous invasion,and the presence or absence of hepatic lobar *** TNM classification,besides the usual descriptors,tumor,node and metastases,provides additional information concerning the possibility for the residual tumor(R) and the histological grade(G).Recently,in 2011,a new consensus classification for the Perihilar cholangiocarcinoma had been *** consensus was organised by the European Hepato-PancreatoBiliary Association which identified the need for a new staging system for this type of *** classification includes information concerning biliary or vascular(portal or arterial) involvement,lymph node status or metastases,but also other essential aspects related to the surgical risk,such as remnant hepatic volume or the possibility of underlying disease.

关键词： Hilar cholangiocarcinoma Klatskin tumor Perihilar cholangiocarcinoma Bile duct cancer

Electrostatic and Magnetostatic Forces That Arise from Electrostatic and Magnetostatic Pressures

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Journal of Electromagnetic Analysis and Applications 2019年第3期11卷 25-40页

作者： José-luis Jiménez-Ramírez Ignacio Campos-Flores José-Antonio-Eduardo roa-Neri Departamento de Física Facultad de Ciencias Universidad Nacional Autónoma de México CDMX México área de Física Teórica y Materia Condensada División de Ciencias Básicas e Ingeniería Universidad Autónoma Metropolitana Unidad Azcapotzalco México D. F. México

With the insight provided by a balance equation of electromagnetic momentum, we compare the force on a dielectric slab inside a capacitor with the force on a magnetizable rod inside a solenoid. We conclude that these forces are not exactly analogous, as usually thought. We present a device that is a proper analogy of the case of a dielectric slab inside a capacitor. Our analysis shows the significance of the electrostatic and magnetostatic pressures to the understanding of these effects and shows the conceptual differences between both cases.

关键词： Polarizable Electric and Magnetic Media Electric and Magnetic Pressures Electromagnetic Force Densities Macroscopic Maxwell Equations Balance Equations of Electromagnetic Momentum

A New Perspective of the Force on a Magnetizable Rod inside a Solenoid

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Journal of Electromagnetic Analysis and Applications 2018年第10期10卷 171-183页

作者： José-luis Jiménez-Ramírez Ignacio Campos-Flores José-Antonio-Eduardo roa-Neri Departamento de Física Facultad de Ciencias Universidad Nacional Autónoma de México México D. F. México área de Física Teórica y Materia Condensada División de Ciencias Básicas e Ingeniería Universidad Autónoma Metropolitana Unidad Azcapotzalco México D. F. México

We analyze the familiar effect of the pulling of a magnetizable rod by a magnetic field inside a solenoid. We find that the analogy with the pulling of a dielectric slab by a charged capacitor is not as direct as usually thought. Indeed, there are two possibilities to pursue the analogy, according to the correspondence used,?either E → B and D → H, or E?→ H and D?→ B. One of these results in an incorrect sign in the force, while the other gives the correct result. We avoid this ambiguity in the usual energy method applying a momentum balance equation derived from Maxwell’s equations. This method permits the calculation of the force with a volume integration of a force density, or with a surface integration of a stress tensor. An interpretation of our results establishes that the force acts at the interface and has its origin in Maxwell′s magnetic stresses at the medium-vacuum interface. This approach provides new insights and a new perspective of the origin of this force.

关键词： Force on a Rod in a Solenoid Magnetostatic Force Maxwell Momentum Balance Equation

Balance Equations of Electromagnetic Angular Momentum

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Journal of Electromagnetic Analysis and Applications 2017年第12期9卷 203-217页

作者： Ignacio Campos-Flores José luis Jiménez-Ramírez José Antonio Eduardo roa-Neri Departamento de Física Facultad de Ciencias Universidad Nacional Autónoma de México Mexico City México área de Física Teórica y Materia Condensada División de Ciencias Básicas e Ingeniería Universidad Autónoma Metropolitana Unidad Azcapotzalco Mexico City México

We give theoretical foundation to torque densities proposed in the past, like the one used by Beth to study experimentally the action of circularly polarized radiation on a birefringent material, or that proposed by Mansuripur to resolve a seeming paradox concerning the Lorentz force law and relativity. Our results provide new insights into electromagnetic theory, since they provide a unified and general treatment of the balance of lineal and angular momentum that permits a better assessment of some torques. Thus in this work we extend the derivations we have made of balance equations for electromagnetic linear momentum to balance equations for electromagnetic angular momentum. These balance equations are derived from the macroscopic Maxwell equations by means of vector and tensor identities and from the different ways in which these equations are written in terms of fields E, D, B, and H, as well as polarizations P, and M. Therefore these balance equations are as sound as the macroscopic Maxwell equations, with the limitations of the constitutive relations.

关键词： Balance Equations Foundations of Electrodynamics Electromagnetic Angular Momentum Macroscopic Maxwell Equations Abraham-Minkowski Controversy

How Does Arise the Force on a Dielectric Slab in a Parallel Plate Capacitor?

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Journal of Electromagnetic Analysis and Applications 2018年第7期10卷 131-142页

作者： Ignacio Campos-Flores José-luis Jiménez-Ramírez José-Antonio-Eduardo roa-Neri Departamento de Física Facultad de Ciencias Universidad Nacional Autónoma de México Mexico City Mexico rea de Física Teórica y Materia Condensada División de Ciencias Básicas e Ingeniería Universidad Autónoma Metropolitana Unidad Azcapotzalco Mexico City Mexico

We address the problem of the force exerted on a dielectric slab partially introduced into a charged parallel plate capacitor. This elementary problem is usually solved calculating this force as the gradient of an energy and attributing its origin to the action of the fringing field outside the capacitor on the dipoles of the dielectric slab. By applying Maxwell’s theory of electromagnetic stresses, we show that this force acts at the interface dielectric-vacuum and originates from the action of these stresses. This approach permits to obtain the force as a volume integration of a force density, or as a surface integral of a stress tensor. This force density and the stress tensor are part of a momentum balance equation derived from Maxwell’s equations.

关键词： Classical Electromagnetism Maxwell Equations Electrostatics Maxwell Balance Equation Maxwell Stress Tensor

Induced Dipoles in Electromagnetic Media in Motion

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Journal of Electromagnetic Analysis and Applications 2018年第11期10卷 185-192页

作者： José-Antonio-Eduardo roa-Neri José-luis Jiménez-Ramírez Ignacio Campos-Flores área de Física Teórica y Materia Condensada División de Ciencias Básicas e Ingeniería Universidad Autónoma Metropolitana Unidad Azcapotzalco México D. F. México Departamento de Física Facultad de Ciencias Universidad Nacional Autónoma de México México D. F. México

We present a non-relativistic approach to the equivalent polarization Peq=(1/c2)v×Meq, that appears in a magnetized medium in motion. We apply an analogous method to that used by Panofsky and Phillips to calculate the symmetric effect, the equivalent magnetization that appears in a polarized dielectric in motion, Meq=P×v,?This method is based on a particular expression of Maxwell’s equations and the application of the convective derivative. These authors argue, however, that the equivalent polarization can be obtained only with a relativistic approach. We show that with the same method, but with a different and equivalent expression of Maxwell’s equations, this effect can also be calculated. In this way both effects can be considered relativistic effects to first order in v/c.

关键词： Moving Media Polarized Dielectric Macroscopic Maxwell Equations Induction of Magnetic Dipoles

Characterization of oral yeasts isolated from healthy individuals attended in different Colombian dental clinics

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The Journal of Biomedical Research 2019年第5期33卷 333-342页

作者： Raul Eduardo Rivera Alejandra Zuluaga Karen Arango Itzjak Kadar Paola Andrea Pinillos luis Fernando Montes Eugenia Catalina Cepeda Ernesto Gonzalez Pedro Antonio Alfonso Andrea Alejandra Villalba luis Fernando Casanova Adolfo Perez Armando roa Martha Jhoana Arias Jorge Orlando Francisco Cuellar Lorena Pedraza Adiel Alberto Vasquez Blanca Lynne Suarez Beatriz LGomez Catalina De Bedout Luz Elena Cano Group of Investigation in Oral Health Faculty of DentistryAntonio Narino UniversityArmeniaQuindio 630001Colombia Medical and Experimental MycologyUnit Corporation for Biological Research(CIB)MedellinAntioquia 050034Colombia School of Medicine and Health Sciences Universidad del RosarioCarreraBogota 111221Colombia School of Microbiology University of AntioquiaMedellinAntioquia 050036Colombia.

The aim of this study was to identify the most frequent yeasts in the oral cavity of adult individuals without immune disorders and to associate the presence of these oral yeasts with different characteristics of each individual. Oral rinse samples were obtained from 96 healthy adults and cultured in Sabouraud dextrose agar media and CHROMagar. Yeasts were identified by sequencing the D1/D2 region of the 28 S rRNA gene. Probable association among the socio-demographic characteristics, body mass index, family and personal medical history,oral hygiene, tobacco and/or alcohol consumption habits and presence of oral fungi was analyzed. Contingency tables and logistic regression were employed to evaluate possible relationships between the presence of oral fungi and mixed colonization with these variables. 57.3% of the healthy individuals had oral yeasts and 21.8% had mixed colonization. The most prevalent yeasts were Candida albicans(52%), C. parapsilosis(17.9%), and ***(7.57%). Yeasts with most frequently mixed colonization were C. albicans and C. parapsilosis. No relationships were found among the variables analyzed. However, the presence of mixed colonization was related to the presence of dental prostheses(P<0.006), dental apparatuses(P=0.016) and O’Leary index(P=0.012). This is the first study that characterized oral yeasts in Colombian healthy individuals, determined the most prevalent oral yeasts C. albicans, C. parapsilosis and C. dublinensis and an association of mixed colonization with the use of dental prostheses and aparatology and poor hygiene.

关键词： oral yeast Candida species microbial epidemiology

Diagnosis and management of brain metastases:an updated review from a radiation oncology perspective

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Journal of Cancer Metastasis and Treatment 2019年第7期4卷 12-27页

作者： Gutiérrez-Valencia Enrique Sánchez-Rodríguez Irving Balderrama-Ibarra Ricardo Fuentes-LaraJesús Rios-Martínez Alan Vázquez Aldana Arroyo Iñigo Bayardo-López luis Hernández ChávezAllan Puebla-Mora Ana Graciela Nader-roa Liliana Espíritu-Rodríguez Roque Instituto Mexicano del Seguro Social(IMSS) Departamento de Radio-OncologíaCentro Médico Nacional de OccidenteUniversidad de GuadalajaraGuadalajara 44340México Instituto Mexicano del Seguro Social(IMSS) Departamento de Anatomía PatológicaCentro Médico Nacional de OccidenteUniversidad de GuadalajaraGuadalajara 44340México Instituto Mexicano del Seguro Social(IMSS) Departamento de Física MédicaCentro Médico Nacional de OccidenteGuadalajara 44340México

Brain metastasis are the most common intracranial malignancy in the adult population. Their incidence has increased dramatically over the last 20 years, as a result of the increasing number of cases stemming from lung and breast cancer together with the higher cancer survival rates due to diagnostic and therapeutic advances. More than 40%of cancer patients develop brain metastases during the course of their disease: specifically, they appear in 50%of patients with lung cancer, more than 25% of patients with breast cancer, and 20% of patients with melanoma. Diagnosis is made using different imaging approaches, such as computed tomography and magnetic resonance imaging, accompanied by clinical manifestations and a history of malignancy supporting the diagnosis of a brain metastasis. Current treatment options should be oriented to the patient's current performance, the number of intracranial and extracranial lesions, and related factors. Although surgical resection and whole-brain radiotherapy have been standard treatments for many years, numerous treatment modalities have become more easily available and accepted worldwide, producing more favorable and reliable results. Among these is stereotactic radiosurgery, and the latest clinical trials support this treatment.

关键词： Brain metastases whole-brain radiation therapy stereotactic radiosurgery graded prognostic assessment

Foaming supramolecular surfactants for gas mobility control in naturally fractured carbonate reservoirs at high temperature,salinity,and hardness

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Petroleum Science 2022年第6期19卷 3134-3148页

作者： Enrique Soto-Castruita Raúl Hern andez-Altamirano Eduardo Buenrostro-González Erick-Emanuel Luna-Rojero Sung Jae Ko-Kim Violeta-Yasmín Mena-Cervantes Mirna Pons-Jiménez Jorge-Francisco Ramírez-Pérez David-Aaσn Nieto-Alvarez Ricardo Cerón-Camacho Jos e-Ernesto Parra Raúl Oviedo-roa Jos e-Manuel Martínez-Magadán Rodolfo Cisneros-Dévora luis-S.Zamudio-Rivera Instituto Mexicano del Petr oleo Eje Central Lazaro Cardenas Norte 152Col.San Bartolo AtepehuacanCiudad de Mexico07730Mexico CONACy T-Instituto Mexicano del Petroleo Eje Central Lazaro Cardenas Norte 152Col.San Bartolo AtepehuacanCiudad de Mexico07730Mexico Centro Mexicano para la Produccion mas Limpia Instituto Politecnico NacionalAvenida Acueducto s/nCol.La Laguna TicomanCiudad de Mexico07340Mexico Centro de Tecnologías para Exploracion y Produccion Camino de Terracería 800Col.San Jose NovilleroBoca delRíoVeracruz94286Mexico

Oil production and mainte nance are essential issues in naturally fractured reservoirs because they are the largest and most productive on ***,they present early water and gas channeling but could be remediated by using foaming agents to control these phenomena through blocking channeling *** Mexico these reservoirs have pressure up to 5,500 psi,high temperature up to 200℃,salinity up to400,000 ppm,and hardness up to 250,000 ppm;due to these thermodynamic conditions,there has been no available technology to form stable enough *** this work,a foaming supramolecular surfactant with the capability to chelate Ca^(2+)ions is *** a result,surfactant monomers are bridged by captured Ca^(2+)cations leading to the formation of high-molecular-weight oligomers,which significantly increment the viscosity of the solution improving the foam stability,and since at this manner the Ca2+cations are no longer available to precipitate as components of solid salts,the foaming supramolecular surfactant also performs as *** observations are explained through quantum theoretical *** foam is stable,effectively blocking the gas channels,whereas in presence of oil the foam is broken leading the oil to pass into the *** characteristic rheological properties of the foam allow its injection into the formation at a range of flow rates,foam qualities,and shear stress to achieve the flooding and the blocking of a variety of fractured carbonate formations,and the change of the wettability of the matrix,which is a desirable behavior in a huff and puff process,as reported in a previous publication about a successful pilot test of this foam.

关键词： Calcium chelation Foaming composition Supramolecular surfactant Molecular design Gas mobility control Flow assurance Improved oil recovery Conformance control