21 results on '"Carlos Tamayo"'
Search Results
2. Modeling scientific: some theoretical and methodological considerations
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Carlos Tamayo-Roca, Marcia Roca-Revilla, and Graciela Nápoles-Quiñones
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modelación ,actividad científica investigativa ,metodología. ,French literature - Italian literature - Spanish literature - Portuguese literature ,PQ1-3999 ,Social Sciences - Abstract
At present widespread use of models as an auxiliary system to penetrate the essence of phenomena related to all areas of cognitive and transforming activity of man, covering as diverse as human sciences fields. In the field of education use it is becoming more common as essential to transform school practice and enrich their theoretical instrument bitter day. The paper deals with the development of theoretical modeling as a scientific method to advance the process to be transformed and characterized by establishing relationships and links between the structural components that comprise it. In this regard it is proposed as an objective socialize some theoretical and methodological considerations that favor the use of modeling method in the scientific research activity of teachers.
- Published
- 2017
3. Didactic model of the dynamics of motivation for learning Physics
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Dayalis Baralt-Ramos, Jorge Luis Barrera-Romero, Margarita Despaigne-Hechavarria, and Carlos Tamayo-Roca
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motivación ,aprendizaje ,dinámica ,divulgación ,Education (General) ,L7-991 ,Special aspects of education ,LC8-6691 - Abstract
This paper addresses the proposal of a didactic model of the dynamics of the motivation for learning of physics, which is based on the theoretical systematization of communicative interdisciplinarity as conception of Barrera (2003) and pedagogical professional pre approach Despaigne (2012) for teachers in training career mathematically Physics. The same is rooted in systemic-structural method. This educational model will be implemented in practice through a strategy of the same nature for motivation for learning physics with what can contribute to the solution of the dialectical contradiction between what is understood, cognitive self-reflection of teachers in training and given the experiences and feelings related to what you learn, invigorated by the method of disclosure teaching of science
- Published
- 2016
4. Professional formation of school librarian since a pedagogical perspective
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Aniuska Tito-Durán and Carlos Tamayo-Roca
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bibliotecario escolar ,formación profesional ,formación pedagógica ,Education (General) ,L7-991 ,Special aspects of education ,LC8-6691 - Abstract
Deals with the present situation of the process the professional librarians´ logic training, as well as, the role they play as active protagonists within the society of information and in the support to the educative change. The aim of this piece of paper is to think about the school librarian´s teaching functions ,taking into account the methodological matter, the orientation and the research-upgrading. There used methods of investigation of the empiric and theoretical level, such as: historical-logical, analysis and synthesis, induction deduction; observation, survey and interview.
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- 2016
5. La educación sexual
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Fernando Cardona Arango, Bernardo Restrepo Gómez, Guillermo Londoño Restrepo, Carlos Tamayo Lopera, Alfonso Hubiz Jasbun, Jorge Restrepo Salazar, Bernardo Ospina Román, and Angela Restrepo de Ocampo
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Gynecology and obstetrics ,RG1-991 - Abstract
Existen características que señalan o definen la inquietud de los hombres en las diferentes épocas de la historia en el campo de la cultura, así́, en la edad del renacimiento, las artes plásticas son su interés primordial y en los actuales momentos, los rápidos adelantos en los medios de comunicación, las ideologías buscando un nivel social estable que beneficie a la comunidad y el interés por el conocimiento científico de todas las esferas de la sexualidad, son los signos de los tiempos que corresponden al mundo de hoy.
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- 1976
- Full Text
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6. First Stranding Record of Fin Whale (Balaenoptera physalus) in the Mexican Waters of the Gulf of Mexico
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Raúl E. Díaz-Gamboa, Carlos Tamayo-Millán, Gaspar Poot-López, Carlos González-Salas, Harold Villegas-Hernández, and Sergio Guillén-Hernández
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Animal Science and Zoology ,Aquatic Science ,Nature and Landscape Conservation - Published
- 2022
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7. Mass Reduction and Enhanced Geometry of a 0.196 Liters Small IC Engine Piston Through Topology Optimization Simulation and Finite Element Analysis
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Adolfo Perez, Armando Valdes, Gilberto Niño, Carlos Tamayo, Armando Roman Flores, and Enrique Cuan-Urquizo
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- 2022
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8. Photoinstability aversion in perovskite solar cell by downconversion cadmium chalcogenide filters
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Carlos Tamayo-Bello, Ángel Sauceda-Carvajal, Rafael Villa-Angulo, and Carlos Villa-Angulo
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Renewable Energy, Sustainability and the Environment ,Atomic and Molecular Physics, and Optics - Published
- 2022
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9. Permian–Triassic boundary volcanism: Hg isotope and elemental Hg proxies in the Meishan and Guryul Ravine successions
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José Antonio Barbosa, Juan Carlos Tamayo, Paulo Ricardo Riedel, Jiubin Chen, Claudio Gaucher, Jorge E. Spangenberg, Natan Silva Pereira, Alcides N. Sial, Luiz Drude de Lacerda, Christoph Korte, Manoj K. Pandit, and Valderez P. Ferreira
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geography ,geography.geographical_feature_category ,Permian ,Isotope ,Geochemistry ,Boundary (topology) ,Volcanism ,Ravine ,Geology - Published
- 2021
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10. Implantación percutánea transeptal de válvula protésica aórtica sobre bioprótesis mitral degenerada
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Alejandro Ceballos, Hernán Donoso, Mauricio Quezada, Ángel Puentes, German Armijo, Christian Backhouse, Luis Nombela-Franco, Pablo Ramirez, and Carlos Tamayo
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Aortic valve ,medicine.medical_specialty ,Mitral regurgitation ,Percutaneous ,business.industry ,Complex disease ,Mitral Valve Insufficiency ,General Medicine ,Surgical procedures ,Surgical risk ,Surgery ,Transcatheter Aortic Valve Replacement ,medicine.anatomical_structure ,Heart Valve Prosthesis ,medicine ,cardiovascular system ,Favorable outcome ,cardiovascular diseases ,business - Abstract
Reintervention of a mitral degenerated bioprosthesis has a high surgical risk, especially in elderly patients with multiple comorbidities. We report a 74 years old female with two previous cardiac surgical procedures and a new structural mitral bioprosthesis deterioration with severe mitral regurgitation. Considering her high-surgical risk, a fully percutaneous treatment was performed with a balloon-expandable aortic valve in mitral position (valve-in-valve) through a transseptal approach with a favorable outcome. This technique is an attractive and effective option with a relatively low rate of complications that could solve this challenging and complex disease.
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- 2021
11. [Percutaneous implantation of an aortic prosthetic valve on a degenerated mitral bioprosthesis. Report of one case]
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Germán, Armijo, Ángel, Puentes, Alejandro, Ceballos, Mauricio, Quezada, Carlos, Tamayo, Hernán, Donoso, Pablo, Ramírez, Christian, Backhouse, and Luis, Nombela-Franco
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Bioprosthesis ,Heart Valve Prosthesis Implantation ,Cardiac Catheterization ,Treatment Outcome ,Aortic Valve ,Heart Valve Prosthesis ,Humans ,Mitral Valve ,Mitral Valve Insufficiency ,Female ,Aged ,Prosthesis Failure - Abstract
Reintervention of a mitral degenerated bioprosthesis has a high surgical risk, especially in elderly patients with multiple comorbidities. We report a 74 years old female with two previous cardiac surgical procedures and a new structural mitral bioprosthesis deterioration with severe mitral regurgitation. Considering her high-surgical risk, a fully percutaneous treatment was performed with a balloon-expandable aortic valve in mitral position (valve-in-valve) through a transseptal approach with a favorable outcome. This technique is an attractive and effective option with a relatively low rate of complications that could solve this challenging and complex disease.
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- 2020
12. Surface-Ground Water Hydraulic Assessment of Coastal Subsurface Barriers under Simulated Rainfall and Sea Level Rise Flooding Conditions: Preliminary Laboratory-Scale Experiments and Model Development
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Carlos Tamayo and Hector R. Fuentes
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Hydrology ,Sea level rise ,Simulated rainfall ,Flooding (psychology) ,Environmental science ,Model development ,Laboratory scale ,Groundwater - Published
- 2019
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13. Miocardiopatía periparto: Caso clínico
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Hernán Donoso, Pilar Acuña, Pablo Sepúlveda, Germán Armijo, Patricio Sanhueza, Byron Sarango, and Carlos Tamayo
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Per partum cardiomyopathy ,heart failure ,bromocriptine - Abstract
Resumen: Se presenta el caso clinico de una mu-jer de 20 anos que presenta insuficiencia cardiaca de rapida instalacion, asociada a sintomas de infeccion respiratoria viral, 9 semanas post parto. Previamente habia presentado hipertension en el puerperio precoz. Se demostro una severa disfuncion sistolica (FE 12%). Se recupero con medidas convencionales del trata-miento de Insuficiencia cardiaca y finalmente recibio bromocriptina basado en reportes favorables de la lite-ratura respecto del uso de este farmaco. En el control al ano de su alta, se mantenia asintomatica pero persistia severa disminucion de la FE (18%) y dilatacion de ca-vidades izquierdas. Se revisa la informacion acerca de esta patologia. 1 Residente de Cardiologia. 2 Cardiologo. 3 Residente de Medicina Interna, 4 Medico Internista. Servicio de Cardiologia. Hospital San Juan de Dios. Universidad de Chile. Correspondencia: Dr. German Armijo.Hospital San Juan de Dios garmijo.md@gmail.com German Armijo 1 , Pilar Acuna 4 , Byron Sarango
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- 2014
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14. Valoración de métodos convencionales y no convencionales para el control del taladrador de las meliáceas en América
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Efrén Hernández, Ricardo Manríquez González, José Antonio Silva, Eduardo Salcedo, Carlos Alexis Palacios, Juan Carlos Tamayo, Melida Martínez, Henry Hernán Medina, and Bayron Alexander Ruiz
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0106 biological sciences ,010602 entomology ,monospecific plantations ,Swietenia macrophylla ,plagas ,Forestry ,Cedrela odorata ,commercial importance ,pests ,010603 evolutionary biology ,01 natural sciences ,importancia comercial ,plantaciones monoespecíficas - Abstract
En el presente artículo de revisión se hace una recapitulación de investigaciones recientes que se han realizado con el propósito de disminuir el efecto negativo producido por los insectos Hypsipyla grandella e Hypsipyla robusta (taladrador de los brotes tiernos) en plántulas pertenecientes a la familia de las meliáceas, destacando la caoba (Swietenia macrophylla) y el cedro (Cedrela odorata), consideradas de suma importancia comercial por su estructura y calidad de la madera en la industria forestal, se ha identificado a Hypsipyla spp. como una plaga potencial y de interés comercial por atacar a las plantas en los primeros estadios de vida, puesto que el ataque induce a la formación excesiva de ramas, malformación de fustes y, en el peor de los casos, la muerte de las plántulas afectadas en plantaciones monoespecíficas, desde el uso de agentes químicos (insecticida y feromonas), manejo de la sombra en plantaciones, implementación de buenas prácticas silviculturales, control biológico y la combinación de plantas con principios alelopáticos hacia la plaga en cultivos forestales, son algunas de las alternativas evaluadas in situ y ex situ a fin de controlar o erradicar la plaga que por muchos años ha sido objeto de estudio por investigadores.
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- 2016
15. Glándula pineal humana, factores reguladores de la producción de melatonina: morfometría, celularidad y células c-kit
- Author
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Juan Carlos Araya, Paola Vacarisas, Juan Inostroza, H. Rodríguez, Iván Suazo, Pedro Sánchez, Omar Espinoza-Navarro, Carlos Tamayo, and Beatriz Olías
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Reproductive Medicine ,Urology - Abstract
Resumen Introduccion La glandula pineal es una glandula endocrina derivada del diencefalo y septada por derivados piales, por lo que su morfometria y celularidad pudieran quedar definidos durante los primeros anos de vida (proliferacion y apoptosis celulares). En la estroma de la glandula pineal se describen astrocitos derivados de la glia. Sin embargo, no se mencionan la presencia de celulas c-kit+ (CD-117). Objetivos Este trabajo plantea estudiar la morfometria y celularidad, y la presencia de celulas c-kit en la glandula pineal humana a distintas edades, permitiendo demostrar la presencia de celulas con actividad de proteincinasa III. Material y metodos Se obtuvieron glandulas pineales humanas de preparaciones anatomicas frescas: a) grupo 1, de 1 a 6 anos, n = 6; b) grupo 2, de 12 a 17 anos, n = 3; c) grupo 3, de 20 a 30 anos, n = 3, y d) grupo 4, de 35 anos de edad, n = 3. Las muestras fijadas en formol (pH, 7,2) durante 48 h se impregnaron en parafina, y se montaron en portaobjetos silanizados secciones de 5 μm. Las secciones, hematoxilina/eosina, se examinaron para la descripcion histologica y cuantificacion del diametro lobulillar (μm), area del nucleo de los pinealocitos (mm2) e inmunohistoquimica con uso de anticuerpos especificos para la identificacion de: c-kit (DAKO A4502), ki-67 y apaf-1 (Vector Co.). Resultados y discusion Se observaron cambios dinamicos en la morfometria y celularidad (pinealocitos) de la glandula pineal humana segun la edad, con un aumento en el tamano celular hacia la edad de adulto joven y de la proliferacion celular durante la adolescencia, en conjunto con una alta tasa de apoptosis inicial y su disminucion progresiva a traves de la vida. En recien nacidos las celulas c-kit+ no estan presentes. Sin embargo, en los grupos 2, 3 y 4, se encontraron celulas c-kit+, con un aumento en adolescentes y adultos jovenes. Las celulas se presentan como estructuras de nucleo eliptico fuertemente tenidas en el intersticio de la glandula. Aparentemente, la glandula pineal humana termina su desarrollo hacia la pubertad, con la aparicion de celulas c-kit, que podrian participar como focos de depolarizacion de membrana para la liberacion de melatonina. Paralelamente aparecen signos de degeneracion a traves de la presencia de estructuras calcareas calcificadas.
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- 2007
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16. Stochastic management modeling of a pump and treat system at the Rocky Mountain Arsenal near Denver, Colorado
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James W. Warner, Carlos Tamayo-Lara, Esmaeil Khazaei, and Fakhri Manghi
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Hydrology ,Hydrogeology ,Hydraulic conductivity ,Kriging ,Flow (psychology) ,Monte Carlo method ,Environmental science ,Groundwater recharge ,Groundwater model ,Water Science and Technology ,Plume - Abstract
Past activities at the Rocky Mountain Arsenal in Colorado, now the Rocky Mountain Arsenal Urban Wildlife Refuge, have resulted in groundwater contamination of the shallow alluvial aquifer. In response the US Army and Shell Chemical Company, the responsible parties, have implemented a series of pump and treat systems to intercept the contaminated groundwater. This paper discusses a stochastic groundwater model for the management of a pump and treat system located in the Offpost operable unit at the Rocky Mountain Arsenal. The local hydrogeology at the site is complex, which resulted in an intricate array of pumping wells, recharge wells and trenches. The goal of the modeling effort was to develop operational guidelines for the pump and treat system, which took into account uncertainties in hydraulic conductivity while minimizing the likelihood that contaminated groundwater would bypass the system. The modeling approach treated hydraulic conductivity as a stochastic variable and incorporated its uncertainty in system performance by using geostatistical conditional simulations. The Turning Bands and Kriging methods were used to generate a series of equally probable hydraulic conductivity distributions, which preserved the measured hydraulic conductivity values at sampled locations, as well as maintained the same statistics and spatial correlation structure of the known data. Generated hydraulic conductivity distributions were implemented as input to a finite element flow and transport model in order to simulate the performance, within a Monte Carlo framework of management scenarios, of the operation of the pump and treat system. Particle tracking simulations were utilized to determine the effectiveness of the system to intercept the plume under varying uncertainties in the hydraulic conductivity distribution in order to identify an optimal pumping and recharge strategy to prevent contaminated groundwater bypassing the system. The analyses were carried out statistically based upon the probability to capture the plume and to reduce the concentration levels to regulatory standards for a given operational time period. Results allowed improvement in the operation of the system and provided an excellent tool in the decision-making process for the management of contaminated groundwater.
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- 2006
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17. Analysis of clinical-pathologic variables, staging and prognostic groups, and therapeutic results of 106 germ-cell testicular tumors
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Angeles Sanchís, Bonet, Eva Golmayo, Muñoz-Delgado, Francisco José Ortiz, Vico, Juan Carlos Tamayo, Ruiz, and Manuel Sánchez, Chapado
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Adult ,Male ,Adolescent ,Chemoradiotherapy, Adjuvant ,Kaplan-Meier Estimate ,Middle Aged ,Neoplasms, Germ Cell and Embryonal ,Prognosis ,Survival Analysis ,Disease-Free Survival ,Young Adult ,Testicular Neoplasms ,Risk Factors ,Spain ,Cryptorchidism ,Biomarkers, Tumor ,Confidence Intervals ,Humans ,Orchiectomy ,Follow-Up Studies ,Neoplasm Staging - Abstract
Retrospective review of 106 germ-cell testicular tumors treated in our center between 1992 and 2009.Description and analysis of several clinical-pathologic and prognostic variables and survival analysis.68% of our patients were diagnosed in the last 5 years. 54.7% presented seminoma histology. The mean age at diagnosis was 33.47 for the seminoma (S) and 27.63 for non seminoma (NS), p=0,001. The median tumoral size in mm was 45.99mm (globally). 44.3% presented elevation of at least one tumor marker; Alpha-fetoprotein (AFP) or Human chorionic gonadotropin (HCG) .29.3% in the S and 60.4% in NS; p=0.02. The percentage of patients with increased HCG in S was 29.3% and 52.1% in NS; p=0.017 and AFP was elevated in 5.2% of S and 45.8% of NS; P0.001. Accordingly to the classification of The Royal Marsden Hospital 96.5% of S and 83.2% of NS were diagnosed in stage I-II. Using the classification of the International Germ Cell Cancer Collaborative Group (IGCCG) for patients with advanced disease, 98.2% of S and 83.2% of NS belonged to the good prognostic group. Regarding the risk factors for relapse in stage I S (Rete testis invasion (RTI) and tumoral size (TS)4cm) 28% of our patients presented both risk factors. 18% of stage I NS presented vascular (VI) or lymphatic invasion (LI). Following the treatment protocols in consideration with the histology, stage and risk factors, 100% of stage I S with both risk factors and 100% of NS with vascular or lymphatic invasion received adjuvant therapy. Almost all the stage II-IV S and NS received different protocols of chemotherapy. In 2.8% of stage II NS a retroperitoneal lymph node dissection was performed. Residual tumor resection was documented in eight patients with stage II-IV NS. With a median follow-up of 60 months, the event free survival (EFS) was 93.3%.Our study has similar characteristics compared to other studies.
- Published
- 2012
18. Histological and Functional Organization in Human Testicle: Expression of Receptors c-kit and Androgens
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Luis Sarabia, M Sepúlveda, H. Rodríguez, Carlos Tamayo, K Moriguchi, Omar Espinoza-Navarro, Juan Carlos Araya, and Juan Inostroza
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Pathology ,medicine.medical_specialty ,Chemistry ,Tubular motility ,Androgen Receptor Positive ,Histology ,Testicle ,Human reproduction ,Interstitial cell of Cajal ,Androgen receptor ,symbols.namesake ,medicine.anatomical_structure ,Interstitial Cajal cells ,medicine ,symbols ,Immunohistochemistry ,Myocyte ,Anatomy ,Receptor ,AR - Abstract
SUMMARY: The objective of this work was identify the presence of interstitial cells of Cajal, muscle cells, nerves and androgen receptor positive cells in adult human testicle, using immunohistochemical detection for c-kit/CD-117, actin smooth muscle specific (ASMS), neurofilament (N) and androgen receptor (AR), respectively. The samples were obtained from patients (n= 10) with diagnosis of prostate cancer, with surgery of orchiectomy. Subsequently were processed by histology and for immunohistochemistry using specific antibodies. It showed the presence of cells c-kit/CD-117, with diverse degrees of positivity, distributed mainly in the interstitial peritubular area of the human testicle. The peritubular myoides cells were positive to the presence of the actin smooth muscle and androgen receptor. The neurofilaments elements (+) only were observed in the vascular tunic. The specific immunohistochemistry describe the presence of the interstitial cells of Cajal in human testicular interstitium, opening a new perspective for the functional interpretation of the testicular cellularity and tubular motility. Possibly associated functionally to peribubulars cells of smooth muscle to regulate the mobility of the seminiferous tubules, whose integration and function would be androgen dependent. The cells that express the c-kit receptor, were found exclusively in the interstitial compartment. This cellular type in addition of the muscular cells of peritubules and the absence of nervous fibers to the interior of the testicle, could be responsible for the regulation of tubular mobility, as it happens in the gastrointestinal apparatus.
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- 2008
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19. Quimioestratigrafia de isótopos de C e Sr de mármores do complexo São Caetano, zona transversal, província estrutural da Borborema : implicações regionais e globais
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SILVA, Juan Carlos Tamayo and SIAL, Alcides Nóbrega
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Isótopos carbono ,Isótopos estrôncio ,Mármores ,Quimioestratigrafia ,Isótopos de oxigênio - Abstract
A composição isotópica de mármores do Complexo São Caetano (CSC), municípios de Flores e Afogados da Ingazeira, Pernambuco, foi usada para se estimar a idade de deposição das seqüências carbonáticas originais (protolito dos mármores) e para se investigar mudanças na composição global da água do mar durante sua deposição. Após comparar-se a curva de variação secular de isótopos de C e Sr para estas sucessões carbonáticas com curvas para seqüências de carbonatos sedimentares bem conhecidas a nível mundial, uma idade Meso- Neoproterozóica (1,1-0,97 Ga) é proposta para a deposição dos carbonatos do CSC. Três diferentes estágios isotópicos (I, II, III) foram definidos e correlacionados com eventos globais que teriam afetado a composição da água do mar durante a transição Meso-Neoproterozóico (1,1-0,97Ga.). Um estagio inicial (I), com valores moderadamente altos de δ13C (~ +3,7 PDB) que refletem um aumento no seqüestro e soterramento do carbono orgânico, associado a um extensivo crescimento crustal ocorrido no auge do ciclo orogênico Grenvilliano. O estagio isotópico II, apresenta valores mais variareis de δ13C, entre -2 e +3 PDB, interpretados como devido ao aumento no aporte de CO2 rico em 12C associado a um evento de riftamento global há 1,05 Ga e ao seqüestro de matéria orgânica rica em 12C através de subdução e formação de arcos magmáticos a nivel global há ~1,0 Ga respectivamente. O estagio isotópico III, com valores de δ13C em torno de +3,7 PDB, evidencia uma continua sedimentação e concomitante soterramento da matéria orgânica, associada `a aglutinação do supercontinente Rodinia. A quimioestratigrafía de isótopos de Sr, com valores de 87Sr86Sr ~0,706 caracterizando o estagio isotópico I, valores um pouco mais variáveis (de 0.706 a 0,707) no estágio isotópico II, e valores em torno de 0,706 caracterizando o estágio isotópico III, apóiam estas idéias. Baseados no intervalo de idade de deposição aqui proposto e em relações geológicas regionais, é possível propor-se que os protólitos sedimentares dos mármores do CSC ter-se-iam depositado após um evento de riftamento na ZonaTransversal da Província Borborema entre 1.4 e 1.05 Ga. Características litológicas da parte siliciclástica do CSC indicam, por outro lado, que este ter-se-ia depositado numa margem continental em ambientes pelágicos. A margem continental, onde foram depositados os sedimentos do CSC foi estabelecida ao norte do Craton São Francisco e suas supracrustais Meso-Paleoproterozóicas associadas. A sedimentação do CSC foi interrompida pela convergência oceânica-continental (subdução) que levou a formação de arco magmático Cariris Velhos. Comparações das curvas isotópicas de variação secular do CSC com as propostas em seqüências sedimentares bem preservadas, indicam que os protolitos dos mármores estudados teriam-se depositado durante um período de subida do nível do mar. Por outro lado, levando-se em consideração que a composição isotópica de C e Sr de carbonatos pode ser alterada por processos pós-deposicionais (e.g diagênese e metamorfismo), possíveis alterações da assinatura isotópica original dos carbonatos (mármores) do SCC, foram investigadas por metodologia multivariada, incluindo: (1) caracterização petrográfica, (2) caracterização dos elementos (elementos maiores e menores), e (3) determinação da composição isotópica dos carbonatos e grafitas associados. Concluiu-se que a alteração da assinatura isotópica de C encontrada em algumas das amostras estudados esta associada à presença de grafita. Uma difusão entre CH4 rico em 12C (derivado da grafita) e os carbonatos é proposta como o mecanismo que afetou a composição isotópica dos carbonatos, causando diminuições em seus valores de δ13C em ambiente fechado durante o metamorfismo. Isto é apoiado pela pouca variação dos valores de δ18O e 87Sr/86Sr; como também pela natureza inalterada dos indicadores de elementos geoquímicos (conteúdos de Sr com media de 1500 ppm, razões de Mn/Sr de 0.006 até 0.140, e razões de Rb/Sr entre 0 e 0.005). Este processo ocorreu sob condições de metamorfismo de baixa pressão e media temperatura, como é apoiado pela paragênese dos mármores (calcita, quartzo, tremolita, moscovita, diopsidio e granada), as quais indicam temperaturas na faixa de 500-7000C. O Intervalo de temperatura para o metamorfismo (514 e 750oC) calculado a partir o termômetro calcita-grafita apóia esta idéia
- Published
- 2004
20. La educación sexual
- Author
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Alfonso Hubiz Jasbun, Jorge A. Restrepo Salazar, Guillermo Londoño Restrepo, Carlos Tamayo Lopera, Bernardo Ospina Román, Bernardo Restrepo Gómez, Fernando Cardona Arango, and Angela Restrepo de Ocampo
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Obstetrics and Gynecology ,lcsh:Gynecology and obstetrics ,lcsh:RG1-991 - Abstract
Existen características que señalan o definen la inquietud de los hombres en las diferentes épocas de la historia en el campo de la cultura, así́, en la edad del renacimiento, las artes plásticas son su interés primordial y en los actuales momentos, los rápidos adelantos en los medios de comunicación, las ideologías buscando un nivel social estable que beneficie a la comunidad y el interés por el conocimiento científico de todas las esferas de la sexualidad, son los signos de los tiempos que corresponden al mundo de hoy.
- Published
- 1976
21. Analysis of clinical-pathologic variables, staging and prognostic groups, and therapeutic results of 106 germ-cell testicular tumors.
- Author
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Bonet AS, Muñoz-Delgado EG, Vico FJ, Ruiz JC, and Chapado MS
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- Adolescent, Adult, Biomarkers, Tumor analysis, Chemoradiotherapy, Adjuvant, Confidence Intervals, Cryptorchidism pathology, Disease-Free Survival, Follow-Up Studies, Humans, Kaplan-Meier Estimate, Male, Middle Aged, Neoplasm Staging, Neoplasms, Germ Cell and Embryonal epidemiology, Neoplasms, Germ Cell and Embryonal surgery, Orchiectomy, Prognosis, Risk Factors, Spain epidemiology, Survival Analysis, Testicular Neoplasms epidemiology, Testicular Neoplasms surgery, Young Adult, Neoplasms, Germ Cell and Embryonal pathology, Testicular Neoplasms pathology
- Abstract
Objectives: Retrospective review of 106 germ-cell testicular tumors treated in our center between 1992 and 2009., Methods: Description and analysis of several clinical-pathologic and prognostic variables and survival analysis., Results: 68% of our patients were diagnosed in the last 5 years. 54.7% presented seminoma histology. The mean age at diagnosis was 33.47 for the seminoma (S) and 27.63 for non seminoma (NS), p=0,001. The median tumoral size in mm was 45.99mm (globally). 44.3% presented elevation of at least one tumor marker; Alpha-fetoprotein (AFP) or Human chorionic gonadotropin (HCG) .29.3% in the S and 60.4% in NS; p=0.02. The percentage of patients with increased HCG in S was 29.3% and 52.1% in NS; p=0.017 and AFP was elevated in 5.2% of S and 45.8% of NS; P <0.001. Accordingly to the classification of The Royal Marsden Hospital 96.5% of S and 83.2% of NS were diagnosed in stage I-II. Using the classification of the International Germ Cell Cancer Collaborative Group (IGCCG) for patients with advanced disease, 98.2% of S and 83.2% of NS belonged to the good prognostic group. Regarding the risk factors for relapse in stage I S (Rete testis invasion (RTI) and tumoral size (TS)> 4cm) 28% of our patients presented both risk factors. 18% of stage I NS presented vascular (VI) or lymphatic invasion (LI). Following the treatment protocols in consideration with the histology, stage and risk factors, 100% of stage I S with both risk factors and 100% of NS with vascular or lymphatic invasion received adjuvant therapy. Almost all the stage II-IV S and NS received different protocols of chemotherapy. In 2.8% of stage II NS a retroperitoneal lymph node dissection was performed. Residual tumor resection was documented in eight patients with stage II-IV NS. With a median follow-up of 60 months, the event free survival (EFS) was 93.3%., Conclusions: Our study has similar characteristics compared to other studies.
- Published
- 2011
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