oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

4 ( 1 )

2020 ( 2 )

2019 ( 215 )

2018 ( 313 )

Custom range...

Search Results: 1 - 10 of 241314 matches for " Eduardo Bravo C "
All listed articles are free for downloading (OA Articles)
Page 1 /241314
Display every page Item
Embriopatía por isotretinoína: Un da?o evitable
Troncoso Sen,Mónica; Rojas H,Carla; Bravo C,Eduardo;
Revista médica de Chile , 2008, DOI: 10.4067/S0034-98872008000600012
Abstract: retinoic acid is a widely used drug in the treatment of cystic acné. it has teratogenic effects that depend on the gestational period in which it is used. we report a seven months of female whose mother was exposed to retinoic acid in both pregestational and gestational periods. she had a retardation of psychomotor development and a brain mri showed frontal atrophy and a malformation of the posterior fossa. we discuss the mechanisms ofthe teratogenic effeets of retinoic acid
Embriopatía por isotretinoína: Un da o evitable Isotretinoin embryophaty: Report of one case
Mónica Troncoso Sen,Carla Rojas H,Eduardo Bravo C
Revista médica de Chile , 2008,
Abstract: Retinoic acid is a widely used drug in the treatment of cystic acné. It has teratogenic effects that depend on the gestational period in which it is used. We report a seven months of female whose mother was exposed to retinoic acid in both pregestational and gestational periods. She had a retardation of psychomotor development and a brain MRI showed frontal atrophy and a malformation of the posterior fossa. We discuss the mechanisms ofthe teratogenic effeets of retinoic acid
LESION DE SUSTITUCION ESPLENICA
Eduardo Vega P,Andrés O'Brien S,Pía Bravo M,Cristóbal Bravo C
Revista Chilena de Radiología , 2006,
Abstract:
DESARROLLO Y PUESTA EN MARCHA DE SOFTWARE DE TRACTOGRAFIA
Cisternas E,Jaime; Asahi K,Takeshi; Gálvez M,Marcelo; Rojas C,Gonzalo; Bravo C,Eduardo;
Revista chilena de radiología , 2008, DOI: 10.4067/S0717-93082008000100007
Abstract: diffusion weighted mri can measure the random motion of water molecules in biological tissue. these motions are captured using magnetic gradients that dephase the precession of water molecules that move along the direction of the gradient. dephasings show up as small attenuations in signal intensity.this information can be used in tissues such as muscles, spine, medulla and white matter to measure the ani-sotropy and assess fiber integrity. in this work, a new software for the post-processing of diffusion weighted mri is presented.the software can read dataseis from a variety of scanners. diffusion is modeled using ellipsoids that are represented mathematically by means of a tensor, estimated from entry dataset. various indices such as diffusion tensor eigenvalues, fractional anisotropy, types of anisotropy, mean diffu-sivity, and principal directions are computed. results are interactively visualized by using axial planes or a three-dimensional approach. the software includes a nerve fiber tracing module. this tool works on pc-based workstations through a graphical user interface or by using the command line
OBTENCIóN DE COORDENADAS TALAIRACH A PARTIR DE MAPAS CORTICALES DE AREA VISUAL CON RESONANCIA MAGNéTICA FUNCIONAL
Rojas C,Gonzalo; Cordovez M,Jorge; Gálvez M,Marcelo; Asahi K,Takeshi; Bravo C,Eduardo;
Revista chilena de radiología , 2008, DOI: 10.4067/S0717-93082008000200003
Abstract: : functional magnetic resonance imaging gives detailed information on the location of brain activity. due to the functional-anatomic difference between patients, discrepancies arouse concerning the location of activation areas. to solve this problem, a standard positioning system called talairach coordinates was used. the fmri mapping of visual cortex was performed in 14 healthy volunteers, using colored circles visual stimulation. using fmri post processing software, a combined image of the 14 volunteers fmri was computed. the main activation voxel is (16, -93, 7), that corresponds to brodmann area 17 (primary visual area v1). correlation of the primary visual area (v1) obtained through fmri with brodmann area 17, only proven from the classical literary neurophysiological viewpoint, was confirmed.
CARACTERISTICAS DE LAS HEMORRAGIAS INTRACRANEANAS ESPONTANEAS EN TC Y RM
Marcelo Gálvez M,Eduardo Bravo C,Pablo Rodríguez C,Mauricio Farías A
Revista Chilena de Radiología , 2007,
Abstract: El diagnóstico certero de la hemorragia intracraneana espontánea representa un desafío frecuente en la práctica del radiólogo, por lo que debemos estar familiarizados con esta patología. Este artículo describe las bases neurobiológicas de la evolución natural de los hematomas intracraneanos. Revisa también las características de sus imágenes, considerando la variabilidad de su apariencia en tomografía computada (TC) y resonancia magnética (RM). Además, se describen los signos radiológicos que ayudan en la distinción de hematomas de origen benigno y maligno. Por último, se consideran las causas frecuentes de hemorragia intracraneana espontánea The certain diagnosis of spontaneous intracranial hemorrhage represents a frequent challenge in radiologist practice, creating the need of being familiarized with this pathology . This article describes the neurobiological basis of the usual evolution of intracranial hematomas. It revises the imaging characteristics of its images, considering the variability of its appearance in computed tomography and magnetic resonance. Radiological signs are described and signs that help us in the distinction from benign to malign origin of hematomas. Finally, the frequent causes of spontaneous haemorrhage are described
Contenido de yodo en leche de vacuno procedente de la Sierra y Costa del peru
Cárdenas Quintana,Haydeé; Gómez Bravo,Carlos; Pretell,Eduardo A;
Archivos Latinoamericanos de Nutrición , 2003,
Abstract: summary. iodine content of cattle milk from two milksheds in peru. with the objective to establish the cause-effect relationship between a geological area and the iodine content in cattle milk, and to estimate the contribution of milk consumption to the dietary iodine intake, in the present study it was determined the iodine content in cattle milk from the sierra and the coastal regions of peru.milk samples were collected of cows from the three main productive zones of peru, 62 in cajamarca, 42 in arequipa, both in the sierra, and 27 in lima at the coast.the measurement of iodine was made by the method of zak, based on the sandell- kolthoff reaction. the median values obtained were 24 μg/l in cajamarca, 34 μg/l in arequipa, and 170 μg/l in lima. the median value in the sierra, 26 μg/l, was significantly lower than the one found in the coast. moreover, while in the former 81% of individual values were below 50 ug/l, in the latter, on the contrary, 77 % were above 80 ug/l. these results confirm that the iodine content in cattle milk is related to ecological factors. at the same time, they demonstrate that the iodine content in milk from the sierra is six times lower than in milk from the coast, and also that its consumption does not contribute significantly to satisfy the human physiological requirements of iodine in that zone.
CALCULO DE TIEMPOS T1 Y T2 IN VITRO
Gálvez M,Marcelo; Farías A,Mauricio; Asahi K,Takeshi; Bravo C,Eduardo;
Revista chilena de radiología , 2005, DOI: 10.4067/S0717-93082005000300003
Abstract: the present work deals with the standardization of the parameters of different magnetic resonance sequences, in order to quantify the values of the relaxation times t1 y t2 from the obtained set of images. in vitro images from a 1.5t mr scanner were experimentally obtained for different biological tissues corresponding to muscle, fat and water. from this data the t1 and t2 curves were calculated for the different tissues. the sequences correspond to spin-echo by varying tr for t1, and turbo spin-echo by varying te for t2.finally, the parameters t1 and t2 of the corresponding curves of longitudinal and transversal relaxation were obtained by means of the fitting with the exponential theoretical curves. the experimental t1 values correspond to 951 ms for the muscles, 238 ms for the fat and 2813 ms for the water. the experimental t2 values correspond to 71ms for the muscles, 81 ms for the fat and 704 ms for the water. these studies show the feasibility of calculating this parameter, in order to be utilized for different quantitative analysis of the images for magnetic resonance
CALCULO DE TIEMPOS T1 Y T2 IN VITRO
Marcelo Gálvez M,Mauricio Farías A,Takeshi Asahi K,Eduardo Bravo C
Revista Chilena de Radiología , 2005,
Abstract: El objetivo del trabajo consiste en cuantificar los valores de los tiempos de relajación T1 y T2 a través de una simple modificación de las secuencias convencionales. En forma experimental se obtuvieron imágenes in vitro en un resonador magnético de 1.5T de diferentes tejidos biológicos correspondientes a músculos, lípidos y agua, a partir de las cuales se obtuvieron las respectivas curvas T1 y T2. Las secuencias utilizadas corresponden a espín-eco para las curvas T1 mediante la variación del TR y turbo espín-eco para las curvas T2, por medio de la variación del TE. Finalmente los parámetros T1 y T2 de las respectivas curvas de relajación longitudinal y transversal se obtuvieron mediante el ajuste con las curvas exponenciales teóricas. Los valores T1 resultantes fueron 951 ms para el músculo, 238 ms para los lípidos y 2813 ms para el agua. Los valores T2 resultantes fueron 71ms para el músculo, 81 ms para los lípidos y 704 ms para el agua. Lo anterior demuestra la factibilidad de calcular estos parámetros, con el objetivo de ser utilizados en los diferentes análisis cuantitativos de las imágenes por resonancia magnética The present work deals with the standardization of the parameters of different Magnetic Resonance sequences, in order to quantify the values of the relaxation times T1 y T2 from the obtained set of images. In vitro images from a 1.5T MR scanner were experimentally obtained for different biological tissues corresponding to muscle, fat and water. From this data the T1 and T2 curves were calculated for the different tissues. The sequences correspond to spin-echo by varying TR for T1, and turbo spin-echo by varying TE for T2.Finally, the parameters T1 and T2 of the corresponding curves of longitudinal and transversal relaxation were obtained by means of the fitting with the exponential theoretical curves. The experimental T1 values correspond to 951 ms for the muscles, 238 ms for the fat and 2813 ms for the water. The experimental T2 values correspond to 71ms for the muscles, 81 ms for the fat and 704 ms for the water. These studies show the feasibility of calculating this parameter, in order to be utilized for different quantitative analysis of the images for magnetic resonance
CARACTERISTICAS DE LAS HEMORRAGIAS INTRACRANEANAS ESPONTANEAS EN TC Y RM
Gálvez M,Marcelo; Bravo C,Eduardo; Rodríguez C,Pablo; Farías A,Mauricio; Cerda C,Jorge;
Revista chilena de radiología , 2007, DOI: 10.4067/S0717-93082007000100005
Abstract: the certain diagnosis of spontaneous intracranial hemorrhage represents a frequent challenge in radiologist practice, creating the need of being familiarized with this pathology . this article describes the neurobiological basis of the usual evolution of intracranial hematomas. it revises the imaging characteristics of its images, considering the variability of its appearance in computed tomography and magnetic resonance. radiological signs are described and signs that help us in the distinction from benign to malign origin of hematomas. finally, the frequent causes of spontaneous haemorrhage are described
Page 1 /241314
Display every page Item


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