oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2019 ( 284 )

2018 ( 357 )

2017 ( 359 )

2016 ( 556 )

Custom range...

Search Results: 1 - 10 of 206176 matches for " Ramón Rivas "
All listed articles are free for downloading (OA Articles)
Page 1 /206176
Display every page Item
Consumo de frutas y hortalizas en adolescentes de un colegio privado de Caracas, Venezuela
Albert,Paulina Lorenzana; Bernal Rivas,Jennifer; Dehollain,Juan Pablo; Blanco,Ramón;
Anales Venezolanos de Nutrición , 2002,
Abstract: fruits and vegetables are functional foods since they may be important factors in the prevention of cardiovascular disease and cancer. the objective of this study was to estimate fruit and vegetable consumption and its content of ascorbic acid, b-carotene, and fiber in a sample of 146 adolescents, students in a private school in caracas. data were collected with a food frequency questionnaire developed from information derived from a 24 h recall questionnaire following the strategy suggested by willett. from the data, portions of fruits and vegetables usually consumed and their content of ascorbic acid, b-carotene, and fiber were estimated. in addition, for those students who perceived their intake to be inadequate, the possible reasons were studied, as well as strategies suggested to improve their intakes. results showed that between 70% and 85% of students had adequate (5-9 portions of fruits and vegetables daily) or more than adequate intake, between 15% and 30% did not consume the recommended portions. the main reasons cited include lack of: palatability, availability in canteen, and habit. vitamin c and b-carotene intake was adequate but intake of fiber was below (<70%) that recommended for the majority of students. because boys generally eat a greater volume of food than girls, their intake was better compared to their counterparts. fruits and vegetables eaten by adolescents studied contribute to improve the variety of foods in their diet. since an important number of subject did not consume the recommended portions, education and prevention should start during childhood and adolescence. we recommend a study of adolescents fruits and vegetable intakes from different social strata.
Cambios en las propiedades físicas y químicas de un suelo de sabana bien drenada, con tres sistemas de labranza, en una pastura degradada de Brachiaria humidicola
Silva-Acu?a,Ramón; Sanabria,Damelys; Marcano,Miguelina; Rivas,Editor; Barrios,Renny; Navas,Mariela;
Zootecnia Tropical , 2005,
Abstract: during three years, on a sandy loam soil, at monagas savannas, it was evaluated the effect of tillage in the recovery of a degraded pasture of brachiaria humidicola and its influence in the physical and chemistry properties of the soil. the treatments used were: pasture without tillage (wt), conventional harrow (ch), and one pass of harrow plus one pass of sub-soiling at 40 cm of deep (h+s), using a randomized block design, with three repetitions of 1100 m2. at the beginning of the experiment it was applied 400 kg of acidulated phosphate rock and three months later, 100 kg/ha of urea and 100 kg/ha of k2so4 were applied. the second year it was applied urea, k2so4, and mgso4, using 100, 100, and 50 kg/ha, respectively. it was measured the aerial biomass production, and the disponibility of p2o5, k2o, caco3, and mgo. it was also measured soil acidity, compactation, and humidity. root density of the pasture was measured at 18 months. it was observed that the aerial biomass production of b. humidicola was increased independently of the tillage system used. in the systems hc and h+s were obtained higher production and it was hold up through on time. in the system with tillage the humidity and soil compactation were only affected at the beginning of the experiment. these systems influenced the availability of phosphorus, potassium, calcium, and magnesium with reduction through time, and their higher concentrations were associated to the stratum of 0 at 10 cm of depth.
Imported submicroscopic malaria in Madrid
Ramírez-Olivencia Germán,Rubio José,Rivas Pablo,Subirats Mercedes
Malaria Journal , 2012, DOI: 10.1186/1475-2875-11-324
Abstract: Background Submicroscopic malaria (SMM) can be defined as low-density infections of Plasmodium that are unlikely to be detected by conventional microscopy. Such submicroscopic infections only occasionally cause acute disease, but they are capable of infecting mosquitoes and contributing to transmission. This entity is frequent in endemic countries; however, little is known about imported SMM. The goals of this study were two-fold: a) to know the frequency of imported SMM, and b) to describe epidemiological, laboratorial and clinical features of imported SMM. Methods A retrospective study based on review of medical records was performed. The study population consisted of patients older than 15 years attended at the Tropical Medicine Unit of Hospital Carlos III, between January 1, 2002 and December 31, 2007. Routinely detection techniques for Plasmodium included Field staining and microscopic examination through thick and thin blood smear. A semi-nested multiplex malaria PCR was used to diagnose or to confirm cases with low parasitaemia. Results SMM was diagnosed in 104 cases, representing 35.5% of all malaria cases. Mean age (IC95%) was 40.38 years (37.41-43.34), and sex distribution was similar. Most cases were in immigrants, but some cases were found in travellers. Equatorial Guinea was the main country where infection was acquired (81.7%). Symptoms were present only in 28.8% of all SMM cases, mainly asthenia (73.3% of symptomatic patients), fever (60%) and arthromialgias (53.3%). The associated laboratory abnormalities were anaemia (27.9%), leukopaenia (15.4%) and thrombopaenia (15.4%). Co-morbidity was described in 75 cases (72.1%). Conclusions Results from this study suggest that imported SMM should be considered in some patients attended at Tropical Medicine Units. Although it is usually asymptomatic, it may be responsible of fever, or laboratory abnormalities in patients coming from endemic areas. The possibility of transmission in SMM has been previously described in endemic zones, and presence of vector in Europe has also been reported. Implementation of molecular tests in all asymptomatic individuals coming from endemic area is not economically feasible. So re-emergence of malaria (Plasmodium vivax) in Europe may be speculated.
Infarto talámico bilateral y cognición en paciente con enfermedad de Hodgkin Bilateral thalamic infarction and cognition in patient with Hodgkin's disease
Roberto A. León González,Nuria Mederos Alfonso,Daysi Chi Ramírez,Ivonne Chon Rivas
Revista Cubana de Medicina , 2006,
Abstract: La afectación del sistema nervioso central en la enfermedad de Hodgkin (HDG) es excepcional. Los pacientes con lesiones malignas tienen mayor riesgo de infarto cerebral. Se presentó un paciente con antecedente de enfermedad de HDG quien presentó episodios súbitos de deterioro del nivel de conciencia y que en el período de recuperación mostró severas alteraciones en sus funciones psíquicas superiores con trastornos groseros de la memoria de fijación y evocación, desorientación témporo-espacial, acalculia, perseveraciones, conducta inadecuada y agresividad. Se determinó, mediante estudios imagenológicos, tomografía axial computarizada y resonancia magnética nuclear, el diagnóstico de infarto talámico bilateral. Se concluyó que las lesiones del tálamo que se acompa an de alteraciones de las funciones psíquicas superiores de carácter demencial son comúnmente bilaterales y que es importante diagnosticar estas complicaciones porque la mayoría son tratables. Se recomendó realizar estudios neuropsicológicos periódicos para precisar si existe recuperación evolutiva de los trastornos cognitivos y conductuales o concluir su diagnóstico como una demencia vascular talámica. The affection of the central nervous system in Hodgkin's disease is exceptional. Patients with malignant lesions are at a higher risk for stroke. A patient with history of Hodgkin's disease that had sudden episodes of deterioration of the conciousness level and that in the recovery period presented severe alterations in his higher psychical functions with gross disorders of the fixation and evocation memory, temporospacial disorientation, acalculia, perseverations, inadequate behavior and aggressiveness, was presented. The diagnosis of bilateral thalamic infarction was determined by imaging studies, computerized axial tomography and nuclear magnetic imaging. It was concluded that the thalamus lesions accompanied with alterations of the higher psychical functions of demential character are usually bilateral and that it is important to diagnose these complications, since most of them may be treated. It was recommended to undertake periodical neuropsychological studies to know if there is an evolutive recuperation of the cognitive and behavorial disorders, or to finally diagnose a vascular thalamic dementia.
Linfoma cerebral primario: Efectividad y efectos secundarios del tratamiento oncoespecífico Primary brain lymphoma: Effectiveness and secondary effects of the oncospecific treatment
Roberto A. León González,Fernando Areces Delgado,Daysi Chi Ramírez,Ivonne Chon Rivas
Revista Cubana de Medicina , 2006,
Abstract: Se ha planteado que la efectividad de la quimioterapia para al tratamiento del linfoma primitivo del sistema nervioso central (LPSNC) no es probada, no obstante, el tratamiento intravenoso e intratecal con methotrexate se ha utilizado y se han obtenido resultados satisfactorios. Se presentó el caso de un paciente, con el diagnóstico de LPSNC y una infiltración intraparenquimatosa en la región témporo-parietal izquierda al principio de la enfermedad y, posteriormente, en el ángulo pontocerebeloso homolateral. Se le aplicó tratamiento oncoespecífico, poliquimioterápico sistémico e intratecal y radioterapia holocraneal. Se observó desaparición de las lesiones reportadas en su totalidad, se logró evolución satisfactoria, aunque este paciente tuvo alteraciones severas tardías de sus funciones psíquicas superiores, con progresivos trastornos cognoscitivos y del comportamiento. Se pusieron en evidencia lesiones en el estudio imagenológico consistentes en atrofia cortical, leucoatrofia, sistema ventricular dilatado y áreas hiperintensas en la materia blanca del cerebro sin recurrencia tumoral. Se verificó el impacto positivo de la quimioterapia en el tratamiento del linfoma cerebral primario, así como la neurotoxicidad en el sistema nervioso central causada por el tratamiento oncoespecífico (radioterapia y quimioterapia). Se consideró que la radioterapia y la terapia combinada deben ser solamente utilizadas en los casos de recaídas. Se recomendó llevar a cabo un estudio clínico comparativo con valoraciones neuropsicológicas periódicas para determinar el posible efecto neurotóxico causado por la radioterapia y/o la quimioterapia. Desde el punto de vista clínico-imagenológico, el paciente presentó una leucoencefalopatía atrófica neurotóxica. It has been stated that the effectiveness of chemotherapy for the treatment of primary central nervous system lymphoma (PCNSL) has not been proved; however, the intravenous or intrathecal treatment with methotrexate has been used and satisfactory results have been obtained. The case of a patient with diagnosis of PCNSL and an intraparenchymatous infiltration on the left temporoparietal region at the onset of the disease, and later on the homolateral pontocerebellar angle, is reported. Systemic and intrathecal oncospecific polychemotherapy and holocranial radiotherapy were applied. All the reported lesions disappeared, and a satisfactory evolution was observed, although this patient had severe late alterations of his higer psychical functions with progressive cognoscitive and behavorial disorders. Lesions such as cortical atro
Hiperemesis gravídica en la Maternidad del Hospital "Dr. Adolfo Prince Lara" 1991-1998. Puerto Cabello, Edo. Carabobo. Venezuela
Marianela Rivas G,José Ramón López G,Belkis Colmenares,Daicy Silva G
Revista de Obstetricia y Ginecología de Venezuela , 2001,
Abstract: RESUMEN Objetivo: Analizar la incidencia y aspectos de interés obstétricos de la hiperemesis gravídica. Método: Estudio retrospectivo y descriptivo de 36 casos de hiperemesis gravídica atendidas entre 1991, y 1998 en 34 664 nacimientos. Para el análisis de las variables se incluyeron 34 historias clínicas. Ambiente: Hospital "Dr. Adolfo Prince Lara", Puerto Cabello, Estado Carabobo, Venezuela. Resultados: La incidencia fue de 0,11%, un caso por cada 963 partos. Predominó el grupo de edad de 20-24 a os en el 50% de los casos. Ninguna paciente tuvo control prenatal. Su aparición más frecuente fue en el primer embarazo con 47%. La edad de gestación predominante fue entre 8-12 semanas. El 52,94% de las pacientes presentó desequilibrio hidroelectrolítico. El 78% de los embarazos llegó a término. La mayoría de las pacientes recibió tratamiento con hidratación parenteral, metoclopramida, prometazina y complejo B. Hubo un caso de muerte materna. Conclusión: La hiperemesis gravídica es una patología poco frecuente que se caracteriza por náuseas y vómitos incoercibles, que ameritan hospitalización, y puede llegar a comprometer la vida de la paciente. SUMMARY Objective: To analyze the incidence and interesting aspects of the hyperemesis gravidarum. Method: Retrospective and descriptive study of 36 cases of hyperemesis gravidarum attended from 1991 until 1998 in 34 664 births. For the analysis of the variables 34 clinical records were included. Setting: Hospital "Dr. Adolfo Prince Lara", Puerto Cabello. Carabobo State, Venezuela. Results: The incidence was 0.11%, one case for each 835 births. In 50% of cases prevailed the age group of 20-24 year. There was no prenatal care. The most frequent appearance was in the first pregnancy with 47%. The predominant gestational age was between 8-12 weeks. The 52.94% of patients presented a hydroelectrolitical unbalance. Reached term 78% of pregnancies. Most of the patients received parenteral hydration, metoclopramide, prometazine and B complex. There was one case of maternal death. Conclusion: The hyperemesis gravidarum is a low frequent pathology characterized by nauseas and incoercible vomits that require hospitalization and could compromise he life of the patient.
Placenta previa. Estudio retrospectivo 1988 - 1992
Marianela Rivas G,José Ramón López Gómez,Domenico Capretta C,Belkis Colmenares E
Revista de Obstetricia y Ginecología de Venezuela , 2001,
Abstract: RESUMEN Objetivo: Analizar la incidencia, características obstétricas y complicaciones maternas de la placenta previa. Método: Estudio retrospectivo y descriptivo de 150 casos atendidos entre 1988 y 1992 en 19 854 nacimientos vivos. Ambiente: Maternidad del Hospital "Dr. Adolfo Prince Lara", Puerto Cabello, Estado Carabobo. Resultados: La incidencia fue de 0,76% (1 caso por cada 132 nacimientos), el grupo de edad predominó entre los 27 a 32 a os (40,67%). El 79,33% (119 casos) fueron multíparas, 70% (105 casos) fueron embarazos de término. Complicaciones maternas más frecuentes: hemorragias 31,03%; rotura prematura de membranas 31,03% y trabajo de parto pretérmino 24,13%. El 78,67% terminó por cesárea. El 78% (114 neonatos) tuvieron peso > a 2 500 g. El 65,47% presentaron Apgar ≥ 7 puntos, hubo 1 muerte materna. Conclusión: El manejo expectante de la placente previa, el ultrasonido diagnóstico y el uso de cesárea, han contribuido a disminuir la morbi-mortalidad materno-feta Summary Objective: To analyze the incidence, obstetrical characteristics and maternal complications of placenta previa. Method: Descriptive and retrospective study of 150 cases occurred between 1988-1992 in 19 854 births. Setting: Maternity of the "Dr. Adolfo Prince Lara" Hospital, Puerto Cabello, Carabobo State, Venezuela. Results: The incidence was 0.76% (1 case in 132 birth) there was 1 pp in 132 births. The highest percentage (40.67%) happen in the age group between 27-32 years old. The 79.33% (119 cases) were multiparous, 70% (105 cases) happened in gestation more then 37 week. Maternal complications: Hemorrhage: 31.03%; membrane premature rupture 31.03% and preterm delivery 24.13%. Cesarean section 78.67%. The 78% the of newborn was weight > at 2 500 g. The 65.47% was Apgar ≥ 7. There was 1 maternal death. Conclusion: Expectant management of placenta previa, the use of cesarean section and the ultrasound diagnosis, reduce maternal morbidity and mortality. Equally the safety and efficacy of expectant treatment to improve fetal survival
Descripción del dise o y construcción de un deposito de hormigón pretensado para 80.000 m2 de capacidad de gas natural licuado. Espa a
Fernández de la Reguera, Ramón,Rivas Zaragüeta, José Luis
Informes de la Construccion , 1981,
Abstract: La construcción de un nuevo depósito de 80.000 m3>/sup> de capacidad para almacenamiento de gas natural licuado en la Planta que la Empresa Nacional del Gas, S A. (ENAGAS) tiene en Barcelona, ha sido realizada por la Empresa Auxiliar de la Industria, S/A. (AUXINI) en Agrupación Temporal con PRELOAD SISTEMAS. Esta obra, una de las últimas realizaciones mundiales en el sector, consistente en doble pared de hormigón pretensado, ha permitido a AUXINI constituirse en una de las empresas líderes de la joven y dinámica tecnología criogénica, aportando soluciones constructivas adecuadas para este tipo de depósitos. En el trabajo que sigue se hace hincapié en la descripción del depósito indicando los pormenores constructivos del mismo, tales como la construcción y montaje de la chapa del muro interno, así como el pretensado horizontal tipo Preload utilizado, además de otros procedimientos constructivos como la elevación de la cúpula, la soldadura de la chapa 9% Ni, etc. Este depósito incorpora los últimos requisitos de seguridad que se exigen en el Proyecto de ese tipo de almacenamiento y, por las numerosas innovaciones que se han introducido durante su construcción, ha constituido una obra pionera en su género y de carácter mundial.
Concepción general e hipótesis de dise o en los almacenamientos de gases licuados.Espa a
Fernández de la Reguera, Ramón,Rivas Zaragüeta, José Luis
Informes de la Construccion , 1981,
Abstract: El presente trabajo trata de resumir el estado actual en relación con el dise o de depósitos de hormigón pretensado para el almacenamiento de gases licuados a temperaturas criogénicas, haciendo hincapié en las acciones extraordinarias que condicionan el dise o de este tipo de almacenamientos. El producto criogénico más comúnmente almacenado en forma líquida es el gas natural que se licúa a —165 oC y que, por lo tanto, es el que establece unos mayores requisitos de seguridad en el dise o de estos depósitos. El sumario de trabajo que sigue puede distribuirse en los siguientes apartados: — Necesidad del almacenamiento criogénico. — Factor económico en su transporte y almacenaje. — Distintos tipos de almacenamiento. — Descripción general de un almacenamiento criogénico. — Elementos esenciales de un depósito. — Consideraciones mínimas de seguridad. — Factores fundamentales en las hipótesis de dise o. — Tipos de acciones a considerar. — Acciones extraordinarias de origen interno. — Acciones extraordinarias de origen externo.
Efecto de la forma de colocación y la dosificación potásica sobre el rendimiento del melón (Cucumis melo L.) en el municipio Mara en el estado Zulia
Morales V,D; Ramírez R,R; Rivas S,J; Sandoval V,J; Rincón N,L;
Revista de la Facultad de Agronomía , 2007,
Abstract: four field experiments were carried out with the purpose of studying the interrelation between potassium dose, fertilizer placing way and melon yield. the amounts of k applied were 0, 30, 60 y 90 kg.ha-1, placed in three different ways: central band (cb), lateral and at the end (lb), and by the side of furrow (s). essay was conducted at mara municipality, zulia state. soil is classified as dry tropical forest, with sandy loam soils, typic haplargids. it was used a randomized complete-block design with 12 treatment and four replication. variable studies were number of fruit per plant, fruit size and yield. k showed a highly significative effect on yield, fertilizer placing way and interactions between them. in 2001, in puerto rico and san cristobal farm, the average response of melon to the traditional fertilizer placing form (c) was 31.81 kg.p-1 with an efficiency of 210 kg of melon by kg of applied fertilizer; in cb was found 43.36 kg.p-1 with efficiency of 286 kg and in l 44.20 kg.p-1 with an efficiency of 290 kg. in 2002 in puerto rico (pr) and cartagena (ca) farm, the average response to the traditional placing way was 80.18 kg.p-1 with an efficiency of 529 kg of melon by kg of applied fertilizer, in cb was 87.74 and efficiency of 579 kg. results show that improving the potassium availability in soil as fertilizer placing way, their efficiency would be increase.
Page 1 /206176
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.