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Search Results: 1 - 10 of 515121 matches for " José J.; Villarreal Ríos "
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Detección de anticuerpos circulantes en donantes de sangre en México
Serrano Machuca,José J.; Villarreal Ríos,Enrique; Galicia Rodríguez,Liliana; Vargas Daza,Emma R.; Martínez González,Lidia; Mejía Damián,Alberto F.;
Revista Panamericana de Salud Pública , 2009, DOI: 10.1590/S1020-49892009001000011
Abstract: objective: to detect antibodies to six potentially blood-borne infections in blood donors at a social security institute in querétaro, mexico. methods: a cross-sectional, retrospective, descriptive study was performed using data from the blood bank records of the general regional hospital no. 1, mexican social security institute (imss). from the 6 929 registered donors, those with any antibody to brucellosis, chagas' disease, hepatitis b, hepatitis c, syphilis, and hiv were identified. for the cases presenting any of these infections, the following demographics were analyzed: age, gender, marital status, education, home address, and number of donations made. to estimate overall prevalence, the number of donors with any of the antibodies was divided by the total donors, and then by each of the various infections. results: of the 6 929 donors, 144 were detected with some type of circulating antibody of the six potentially blood-borne infections, with a total prevalence of 2.07% (0-4.4). the prevalence of blood donors with antibodies for hepatitis c was 0.721% (95%ci: 0.522-0.920) and chagas' disease, 0.649% (95%ci: 0.460-0.838). conclusions: identifying the prevalence of blood donors with antibodies for any of these six, potentially blood-borne infections, allows the blood bank at the general regional hospital no. 1 to establish its own epidemiologic profiling. chagas' disease proved to be emergent, calling for urgent control efforts.
Dinámica del flujo de bióxido de carbono y de energía sobre un pastizal natural del norte de México
Zerme?o-González,Alejandro; Ríos-Estudillo,Jorge Aimir; Gil Marin,José Alexander; Cadena-Zapata,Martín; Villarreal-Quintanilla,José ángel;
Bioagro , 2011,
Abstract: as the grassland covers a significant fraction of the continental surface, they may have an important contribution to the sequestration of atmospheric carbon dioxide. for this reason, the objective of this research was to use the eddy covariance method to measure the flux of carbon dioxide (co2) and energy (net radiation, sensible heat, latent heat and soil heat flux), above a natural grassland of northern mexico, to evaluate the rate of co2 assimilation by the vegetated surface and the partitioning of the energy fluxes. the co2 assimilation rate by the grassland was up to 18 μmol·m-2 s-1. the average daily retention of co2 by the grassland (difference between assimilation during daytime and release during nighttime) was 123,081 mmol·m-2, which corresponded to a daily average of 54.12 kg·ha-1. this shows the importance of this ecosystem in the sequestration of atmospheric carbon dioxide. the intrinsic water use efficiency and the energy use efficiency were higher in cloudy days than under conditions of clear sky. net radiation over the vegetated surface was mainly dissipated in latent heat flux, sensible heat flux and in a smaller rate in soil heat flux. this showed the importance of evapotranspiration on dissipating the absorbed radiation by the vegetated surface.
Rotación de residentes de medicina familiar en Unidad de Investigación Epidemiológica y en Servicios de Salud (experiencia de cinco a os) Clerkship of family medicine residents in a Unit of Epidemiological Research (five years experience)
E. Villarreal-Ríos,J. Velázquez-Tlapanco,E.R. Vargas-Daza,L. Martínez-Martínez
Educación Médica , 2008,
Abstract: Introducción. Se presenta la experiencia de cinco a os del Programa de Rotación del Residente de Medicina Familiar en la Unidad de Investigación. Materiales y métodos. El programa fue dise ado por los investigadores de la Unidad de Investigación Epidemiológica y en Servicios de Salud Querétaro, México, y los profesores de la Residencia de Medicina Familiar de la Unidad de Medicina Familiar n.o 16. Durante el segundo a o de residencia, se estableció la rotación por la unidad de investigación con una duración de dos meses, en la que se incluyó el desarrollo de un proyecto de investigación operativa. El programa de trabajo incluyó los contenidos teóricos de metodología de investigación cursados durante el primer a o de residencia. La difusión se realizó al personal directivo en forma oral y por escrito, con la elaboración de la síntesis ejecutiva y del artículo científico. Resultados. Después de cinco a os y cuatro meses, han asistido 40 médicos residentes. Se han desarrollado 39 protocolos de investigación, 23 seminarios, 39 síntesis ejecutivas, dos artículos publicados, un libro con 16 capítulos y otro en prensa. Las presentaciones en congresos incluyeron 34 delegacionales, 16 regionales y 7 nacionales. Conclusión. A cinco a os de implementado el Programa de Rotación de Residente de Medicina Familiar en Unidad de Investigación, se puede afirmar que es productivo. Los resultados a corto y medio plazo así lo demuestran. Introduction. The proposal is to present five years experience of Family Medicine Student in the Research Unit. Materials and methods. Program was designed by Researchers of Epidemiological and Health Services Unit of Querétaro, México and Professors of Family Medicine Residence No 16. Rotation was specified for the second year of the Residence, duration was defined in two months, included theoretical and practical aspect, an operative research project was a requirement. The program contemplated oral presentation to directive personnel and executive synthesis. Results. After five years and four months, 40 Medical Residents have rotated, 39 whit research projects, 23 academic sessions, 39 executive synthesis, two papers, one book, 16 books chapters and one book in press, 34 presentations in local congress, 16 regional and seven national. Conclusion. After five years of Family Medicine Student in research unit, it is possible to affirm that it is productive. Short and medium term results therefore demonstrate.
Global and Hemispherical Interannual Variation of Total Column Ozone from TOMS and OMI Data  [PDF]
José Luis Pinedo-Vega, Mario Molina-Almaraz, Carlos Ríos-Martínez, Fernando Mireles-García, J. Ignacio Dávila-Rangel
Atmospheric and Climate Sciences (ACS) , 2017, DOI: 10.4236/acs.2017.73017
Abstract: Daily Total Column Ozone (TCO) measurements compiled from Total Ozone Mapping Spectrometer (TOMS) and Ozone Monitoring Instruments (OMI) were used to analyze the global and hemispherical TCO interannual variations. Two periods of TCO measurements were analyzed separately covering full years. For the 1978-1994 period, the TCO showed a global decade decrease rate of 13.45 DU (about -4.3%). For the Northern Hemisphere(NH) the decade decrease rate was of 12.96 DU (-4.0%), while in the Southern Hemisphere (SH) was of 13.57 DU (-4.5%). These decreases in ozone trends, using the totality of TOMS and OMI satellite measurements, are greater than those reported in literature. The 1998-2014 period global TCO decade decrease rate was of 1.56 DU, corresponding 0.94 DU and 0.138 DU for the NH and SH, respectively. The global TCO variations must show a double annual periodicity, the first one with maxima in March due to the Northern Hemisphere (NH) and the second one during September due to the Southern Hemisphere (SH). However, the maxima due to SH TCO interannual variations have gradually vanished. A disturbance in the SH TCO interannual variations has appeared since 1980; graphically the periodicity brakes down and transforms to a double peak from 1985 and on. This effect can be attributed to the hemispheric impact of the ozone hole at the South Pole. Between October 1, 2004 and December 14, 2005 TOMS and OMI have recorded this disturbance unequivocally. We conclude that the disturbance in SH TCO has an irreversible character.
Rotación de residentes de medicina familiar en Unidad de Investigación Epidemiológica y en Servicios de Salud (experiencia de cinco a?os)
Villarreal-Ríos,E.; Velázquez-Tlapanco,J.; Vargas-Daza,E.R.; Martínez-Martínez,L.; Martínez-González,L.; Galicia-Rodríguez,L.; Ruelas-Candelas,M.R.;
Educación Médica , 2008, DOI: 10.4321/S1575-18132008000200008
Abstract: introduction. the proposal is to present five years experience of family medicine student in the research unit. materials and methods. program was designed by researchers of epidemiological and health services unit of querétaro, méxico and professors of family medicine residence no 16. rotation was specified for the second year of the residence, duration was defined in two months, included theoretical and practical aspect, an operative research project was a requirement. the program contemplated oral presentation to directive personnel and executive synthesis. results. after five years and four months, 40 medical residents have rotated, 39 whit research projects, 23 academic sessions, 39 executive synthesis, two papers, one book, 16 books chapters and one book in press, 34 presentations in local congress, 16 regional and seven national. conclusion. after five years of family medicine student in research unit, it is possible to affirm that it is productive. short and medium term results therefore demonstrate.
Compromiso pulmonar por linfoma no Hodgkin diseminado en un paciente con SIDA
Chernilo S,Sara; Trujillo V,Sergio; Meneses C,Manuel; Ríos,José A; Aguirre,Juan J;
Revista médica de Chile , 2001, DOI: 10.4067/S0034-98872001001100012
Abstract: pulmonary involvement due to disseminated non hodgkin lymphoma (lnh), is an unusual cause of lung disease in aids patients. we report a 38 years old male patient, with advanced aids, who, in the course of three weeks, developed cough, dyspnea and fever. the chest x ray film showed diffuse thickening of the peribronchovascular connective tissue with possible mediastinal lymph node enlargement. the evolution was unfavorable with hypoxemia, severe anemia, liver damage and elevated levels of lactic dehydrogenase. the presumptive initial diagnoses were pneumocystis carinii pneumonia, pulmonary tuberculosis with hematogenous dissemination and kaposi sarcoma. definitive diagnosis was made through a transbronchial biopsy performed the day before his death. the pathological and inmunohistochemical report demonstrated a highly aggressive lymphoma (lymphoblastic, b precursor). this finding was confirmed by autopsy that revealed multiple organ involvement (rev méd chile 2001; 129: 1315-9).
Fertilidad después del tratamiento laparoscópico del embarazo ectópico, en la Clínica del Prado en Medellín, Colombia: Estudio de cohorte Fertility following laparoscopic treatment of ectopic pregnancy at the Prado Clinic in Medellín, Colombia: A cohort study
José F De los Ríos,Enrique Sánchez,Gabriel J Matta,Mauricio Jaramillo
Revista Colombiana de Obstetricia y Ginecología , 2007,
Abstract: Objetivo: conocer y comparar los índices de fertilidad luego de salpingostomía vs. salpingectomía laparoscópicas en pacientes con embarazo ectópico. Dise o y población: cohorte concurrente de pacientes sometidas a cirugía de embarazo ectópico por laparoscopia en la Unidad de Cirugía Endoscópica Ginecológica, Clínica del Prado, Medellín, Colombia. Metodología: revisión de historias clínicas e interrogatorio telefónico a pacientes que cumplieron criterios de inclusión. Variables principales: tasa global de embarazo intrauterino, tasa acumulada por a o de embarazo intrauterino, tasa de recurrencia de ectópico, tasa de persistencia de ectópico. Resultados: 31 pacientes en el grupo de salpingostomía y 14 pacientes en el grupo de salpingectomía. La tasa global de embarazo intrauterino después de salpingostomía fue de 54,8% comparada con 57,1% para salpingectomía (p = 0,88). Se presentaron recurrencias en el 10,5% de las salpingostomías y en el 20% de las salpingectomías (p = 0,77). La tasa de persistencia de ectópico después de manejo conservador fue de 9,6%. Conclusiones: este estudio no demuestra diferencias significativas en los índices reproductivos al comparar salpingostomía vs. salpingectomía laparoscópicas. Objective: obtaining and comparing fertility rates after laparoscopic salpingostomy and salpingectomy in patients suffering ectopic pregnancy. Sample and design: a concurrent cohort of patients being operated on by laparoscopy for ectopic pregnancy in the Clínica del Prado’s Gynecological Endoscopic Surgery unit, Medellín, Colombia. Methods: reviewing medical records and conducting a telephone questionnaire of patients who matched the inclusion criteria. Main outcomes: overall intrauterine pregnancy rate, cumulative intrauterine pregnancy rate, recurrence rate, persistence rate. Results: overall intrauterine pregnancy rate for the 31 patients following salpingostomy was 54.8% compared to 57.1% for the 14 patients in the salpingectomy group (p=0.88). Recurrence rates were 10.5% for the salpingostomy group and 20% for salpingectomy patients (p=0.77). There was 9.6% persistence of ectopic pregnancy in the salpingostomy group. Conclusions: the present study did not demonstrate a statistically significant difference in the reproductive outcome of patients being laparoscopically managed by either salpingostomy or salpingectomy.
Evolución del comportamiento alimentario de cabras criollas en especies arbóreas y arbustivas durante el pastoreo trashumante, México
Franco-Guerra,Francisco J; Sánchez-Rodríguez,Manuel; Hernández Hernández,Jorge E; Villarreal Espino-Barros,Oscar A; Camacho Ronquillo,Julio C; Hernández Ríos,María A;
Zootecnia Tropical , 2008,
Abstract: the present study was carried out to determine the evolution of the alimentary selectivity of creole goats grazing in transhumant pastures in five rangelands in the mountain of the mixteca oaxaque?a. six animals were chosen at random and the method of direct observation of the grazing was used. the different preference levels and the effects of the rangeland and species factors, and their interaction were evaluated. the results indicated that only seven of 18 woody species of more preference were consumed repeatedly by the goats: quercus liebmannii, cercocarpus macrophyllus, eysenhardtia polystachya, amelanchier denticulata, acacia pennatula, acacia farnesiana, and mimosa lacerata, being due in great extent to its endemic condition and its abundant cover in the studied rangeland.
Calidad del Programa de Detección Oportuna de Cáncer Cervicouterino en el estado de Nuevo León
Salud Pública de México , 1997, DOI: 10.1590/S0036-36341997000300003
Abstract: objective. to determine the quality of the early cervical cancer detection program in the state of nuevo león. material and methods. a random selection of 4 791 cytologic reports were analyzed, emitted by the state ministry of health, the university hospital and the mexican institute for social security early cervical cancer detection modules. pap tests of women with hysterectomy, current pregnancy, menopause or positive result were excluded. quality was measured with previously defined standards. analysis included, besides univariate statistics, tests of significance for proportions and means. results. the quality of the program was fairly satisfactory at the level of the state. the quality of the sampling procedure was low; 39.9% of the tests contained endocervical cells. quality of coverage was low; 15.6% were women 25 + years with first time pap test. quality of opportunity was high; 8.5 ± 7 weekdays between the date of the pap smear and the interpretation date. conclusions. strategies are needed to increase the impact of the state program, such as improving the sampling procedure and the coverage quality levels.
Improved Low-Temperature Aqueous Synthesis of ZnO Nanorods and Their Use in SERS Detection of 4-ABT and RDX  [PDF]
Marcia del R. Balaguera-Gelves, Oscar J. Perales-Pérez, Surinder P. Singh, José A. Jiménez, Joaquín A. Aparicio-Bola?os, Samuel P. Hernández-Rivera
Materials Sciences and Applications (MSA) , 2013, DOI: 10.4236/msa.2013.41005

The growth-controlled synthesis of zinc oxide nanorods (ZnO NR) in the aqueous phase has been investigated. The rods were grown on ZnO films previously deposited onto Si(100) and indium tin oxide (ITO) substrates by RF magnetron sputtering. The formation of the rods took place in the presence of hexamethylenetetramine (HMT) as habit-control reagent. The grains in the base ZnO film acted as seeds that promoted the longitudinal growth of the oxide. As-synthesized base films and rods were characterized by X-ray diffraction, scanning electron microscopy (SEM), field emission SEM, optical absorption and photoluminescence spectroscopy techniques. Subsequently, a wet chemistry procedure was performed to achieve ZnO NR growth. This methodology was conducive to the formation of rods of a relatively narrow distribution of diameters (60 - 70 nm) with lengths in the 1 - 3 μm range. Photoluminescence spectra were characterized by a dominant near-band-edge (NBE) peak followed by a green luminescence (GL) broad band, indicative of higher oxygen vacancy concentration in the ZnO NR grown on ZnO/ITO in comparison with those grown on ZnO/Si(100). A UV process was used for coating the ZnO NR with gold (Au). Au coating on ZnO NR was used to evaluate the detection capability by SERS of different analytes such as: 4-aminobenzenethiol (4-ABT) and 1,3,5-trinitroperhydro-1,3,5- triazine (RDX) at low levels. A strong SERS Raman spectrum was observed for 4-ABT. A limit of detection (LOD) of 1 × 10-8M for 4-ABT was achieved corresponding to a minimum of 5.4 × 105molecules detected under the experimental conditions at excitation wavelength of 785 nm with a sensitivity of the ZnO

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