971 resultados para mv


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Dentro del marco del aborto involuntario recurrente (AIR), se han propuesto causas autoinmunes y alogénicas, e implementación de terapias como la inmunización activa con leucocitos alogénicos de la pareja o de donantes. La evidencia disponible en cuanto a la efectividad de estos tratamientos es contradictoria, por lo que se desea realizar una revisión sistemática para evaluar la efectividad de la inmunización activa con leucocitos alogénicos de la pareja o de donantes para esta condición. Se realizó un estudio tipo revisión sistemática de la literatura, usando las siguientes bases de datos: Medline, Embase, Cochrane Library y Scielo. Se realizó una búsqueda a través del registro de ensayos clínicos del Instituto Nacional de Salud de los Estados Unidos (www.clinicaltrials.gov) y, una búsqueda manual a través de las referencias de los estudios seleccionados siguiendo la estrategia de bola de nieve. Se seleccionaron ensayos clínicos y estudios de cohorte analítica, en idioma inglés y español. Se realizó un análisis cuantitativo de la información por medio de un metaanálisis. El tratamiento inmunomodulador con linfocitos puede considerarse como una terapia efectiva para mantener la gestación y lograr recién nacido vivo según resultados estadísticos; sin embargo la calidad de los estudios incluidos es baja, por lo que no se aconseja para la práctica rutinaria. Se sugiere la realización de estudios con metodologías robustas y que apoyen los resultados presentados en esta investigación.

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La diabetes mellitus es una de las patologías frecuentes durante el embarazo, existe literatura que la ha relacionado con un mayor riesgo de aparición de incontinencia urinaria en el postparto patología que de manera clara afecta la calidad de vida de las mujeres, pero a la fecha la literatura no es concluyente. Con la presente revisión sistemática se pretendió evaluar la evidencia relacionada con la diabetes gestacional como causa de incontinencia urinaria en el postparto.

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Introducción: El trauma vascular en nuestro país es común, causando mortalidad en la población entre 15-44 años; como causa principal, las heridas por arma corto punzante en los miembros superiores lideran sobre las de arma de fuego y los miembros inferiores. En Colombia se cuenta con algunos registros de trauma vascular secundario a la guerra, por lo que con este trabajo buscamos describir la población afectada de la localidad octava como punto inicial para estudios analíticos. Metodología: revisión de la base de datos de los pacientes llevados a cirugía en el hospital de Kennedy, de los cuales se extrajeron aquellos con trauma vascular, recolección de las variables a estudiar y análisis de las mismas. Resultados: encontramos 1267 pacientes que consultaron por trauma, de ellos 32 cursaron con trauma vascular, llevados a cirugía(0,3%), el promedio de edad fue de 24 años, la mayoría de sexo masculino (84%); el 72% fueron heridas por arma blanca, 56% fueron heridas múltiples, afectando en el 41% a las extremidades superiores; las lesiones en cuello casi igualan a las heridas en miembros inferiores con un 28%, solo se presentó un caso de amputación y no se presentaron mortalidades. Discusión: en Colombia hacen falta estudios acerca de esta patología que aunque común esta subpublicada, este estudio es tan solo un paso que nos introduce en las características demográficas, y algunas característica clínicas interesantes en comparación a la literatura mundial consultada

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Validar el constructo de la madurez vocacional basado en el modelo estructural y de desarrollo de Super y Crites y estudiar la relación y el valor predictivo de las variables asociadas a la MV. 1.- 539 sujetos de ambos sexos que cursan octavo de EGB, segundo de FP y BUP, quinto de FP y COU, pertenecientes a tres centros de zona urbana de Barcelona capital y a tres centros de zona suburbana. Son elegidos según muestreo intencionado por conglomerados. 2.- 287 sujetos de las mismas características que los anteriores. Plantea las bases teóricas del constructo de la madurez vocacional, las hipótesis y variables. V. Dep.: Grado de desarrollo de la madurez vocacional. V. Ind.: Edad, curso, sexo, zona, inteligencia, madurez psicosocial, status socioeconómico y estilos cognitivos. Valida el constructo de la MV. Adapta el cuestionario CDI y mide las variables aplicando una batería de tests. Realiza un análisis de datos multivariado con el SPSSX para comprobar la estructura factorial de la MV, su relación con las V. independientes, su nivel predictivo y la diferencia de medias. Intervención basada en un programa de simulación para la toma de decisiones. Diseño pretest posttest con grupo control. Aplica dos instrumentos estandarizados y analiza los datos con pruebas de significación. Cuestionario de desarrollo vocacional (CDI) de Super, prueba d-48, cuatro instrumentos sobre estilos cognitivos, Epreuve de Development Psychosocial, programa de simulación de toma de decisiones e inventario de destrezas para toma de decisiones. Modelo estructural y de desarrollo de Super y Crites. Análisis factorial, análisis de correlación de Spearman, análisis multivariado de varianza, análisis de regresión, t-Student, análisis de covariancia y análisis de contenido. Validez de constructo, contenido, criterio y fiabilidad. SPSSX. La adaptación del CDI supone mayor independencia de las dimensiones actitudinal y cognitiva, mejorando el constructo de la MV; las escalas de la MV no están relacionadas con el medio urbano o suburbano pero sí con el curso. Algunas están relacionadas con el sexo y nivel ocupacional del padre. Hay una relación moderada con el nivel de inteligencia, los estilos cognitivos y la madurez psicosocial. Las variables poseen un relativo valor predictivo (21) si se toma la escala global. Hay diferencia significativa en el pretest y posttest del grupo experimental respecto al programa de intervención. Se ha de mejorar el autoconocimiento de los alumnos, facilitar los recursos y la información que necesitan en su proceso de toma de decisión. Se ha de ayudar al alumno a desarrollar e interiorizar las estrategias necesarias para asumir el proceso de la toma de decisión y ayudarle a acercarse al mundo del trabajo para que ese paso no sea traumatizante y angustioso.

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Resumen tomado del autor

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O ácido azelaico é um fármaco com actividade bacteriostática para muitos microorganismos sendo por isso frequentemente aplicado no tratamento do acne. Porém, às formulações tópicas deste fármaco estão geralmente associados alguns efeitos adversos e fracas adesões à terapêutica. Assim, a nanotecnologia pode ser aqui considerada como uma estratégia inovadora para ultrapassar os obstáculos anteriores. O objectivo deste estudo centrou-se no desenvolvimento e caracterização de nanopartículas de PLGA contendo o ácido azelaico. As nanopartículas foram produzidas através do método modificado de emulsificação/difusão do solvente e posteriormente incluídas num gel de Carbopol 940. Foram caracterizados vários parâmetros da formulação tais como potencial zeta, tamanho da partícula e eficiência de encapsulação. O tamanho médio das partículas foi de 378,63 nm (com I.P. cerca de 0,09) e o potencial zeta foi de -7,82 mV. Aeficiência de encapsulação do ácido azelaico foi de 76 ± 3,81%. Consequentemente, estas nanopartículas poderão ser consideradas ferramentas úteis para a veiculação do ácido azelaico.

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A dermatite atópica é uma patologia cutânea crónica que requer cuidados intensivos da pele e tratamento farmacológico; contudo, os tratamentos disponíveis necessitam urgentemente de ser melhorados, especialmente quando utilizados por períodos longos ou em grupos específicos (ex: crianças). A nanotecnologia tem contribuído com sistemas de veiculação inovadores e pode oferecer terapias efectivas e direcionadas. Os objectivos deste estudo centraram-se na preparação caracterização das nanopartículas de policaprolactona carregadas com acetato de hidrocortisona em termos das propriedades físico-químicas, eficiência de encapsulação, ensaios de libertação in vitro e ensaios de segurança dos excipientes utilizados em voluntários humanos. As nanopartículas produzidas apresentaram um tamanho médio de 258,4 24,5 nm e um índice de polidispersão de 0,084. O potencial zeta foi -4,39 0,62 mV e a eficiência de encapsulação foi 36,32 0,03 %. A libertação in vitro do fármaco foi controlada ao longo do tempo. Além disso, os testes de segurança indicaram que os excipientes foram bem tolerados. Este estudo demonstra que as nanopartículas de policaprolactona são sistemas estáveis para veiculação de acetato de hidrocortisona que poderão conduzir a uma libertação prolongada do fármaco, com resultados promissores ao nível da sua segurança quando aplicados na pele humana.

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Suppression of depolarizing postsynaptic potentials and isolated GABA-A receptor-mediated fast inhibitory postsynaptic potentials by the muscarinic acetylcholine receptor agonist, oxotremorine-M (10 microM), was investigated in adult and immature (P14-P30) rat piriform cortical (PC) slices using intracellular recording. Depolarizing postsynaptic potentials evoked by layers II-III stimulation underwent concentration-dependent inhibition in oxotremorine-M that was most likely presynaptic and M2 muscarinic acetylcholine receptor-mediated in immature, but M1-mediated in adult (P40-P80) slices; percentage inhibition was smaller in immature than in adult piriform cortex. In contrast, compared with adults, layer Ia-evoked depolarizing postsynaptic potentials in immature piriform cortex slices in oxotremorine-M, showed a prolonged multiphasic depolarization with superimposed fast transients and spikes, and an increased 'all-or-nothing' character. Isolated N-methyl-d-aspartate receptor-mediated layer Ia depolarizing postsynaptic potentials (although significantly larger in immature slices) were however, unaffected by oxotremorine-M, but blocked by dl-2-amino-5-phosphonovaleric acid. Fast inhibitory postsynaptic potentials evoked by layer Ib or layers II-III-fiber stimulation in immature slices were significantly smaller than in adults, despite similar estimated mean reversal potentials ( approximately -69 and -70 mV respectively). In oxotremorine-M, only layer Ib-fast inhibitory postsynaptic potentials were suppressed; suppression was again most likely presynaptic M2-mediated in immature slices, but M1-mediated in adults. The degree of fast inhibitory postsynaptic potential suppression was however, greater in immature than in adult piriform cortex. Our results demonstrate some important physiological and pharmacological differences between excitatory and inhibitory synaptic systems in adult and immature piriform cortex that could contribute toward the increased susceptibility of this region to muscarinic agonist-induced epileptiform activity in immature brain slices.

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Increasing areas of altered wetland are being restored by re-flooding the soil. Evidence in the literature indicates that this practice can induce the redox-mediated release of soil nutrients, thereby increasing the risk of diffuse water pollution. However, for the sake of improving wedand management decisions, there is a need for more detailed studies of the underlying relationship between the hydrological and redox dynamics that explain this risk; this is particularly the case in agricultural peatlands that are commonly targeted for the creation of lowland wet grassland. A 12-month field study was conducted to evaluate the relationship between hydrological fluctuations and soil redox potential (Eh) in a nutrient-rich peat field (32 g N kg(-1) and 1100 mg P kg(-1) in the surface 0-30 cm soil) that had been restored as lowland wet grassland from intensive arable production. Field tensiometers were installed at the 30-, 60- and 90-cm soil depths, and Pt electrodes at the 10-, 30-, 60- and 90-cm depths, for daily logging of soil water tension and Eh, respectively. The values for soil water tension displayed a strong negative relationship (P < 0.001) with monthly dip well observations of water table height. Calculations of soil water potential from the logged tension values were used, therefore, to provide a detailed profile of field water level and, together with precipitation data, explained some of the variation in Eh. For example, during the summer, alternating periods of aerobism (Eh > 330 mV) in the surface, 0-10 cm layer of peat coincided with intense precipitation events. Redox potential throughout the 30-100 cm profile also fluctuated seasonally; indeed, at all depths Eh displayed a strong, negative relationship (P < 0.001) with water table height over the 12-month study period. However, Eh throughout the 30-100 cm profile remained relatively low (< 230 mV), indicating permanently reduced conditions that are associated with denitrification and reductive dissolution of Fe-bound P. The implications of these processes in the N- and P-rich peat for wetland plant diversity and water quality are discussed. (c) 2006 Elsevier B.V. All rights reserved.

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A highly stable microvolt amplifier for use with atmospheric broadband thermopile radiometers is described. The amplifier has a nominal gain of 500, for bipolar input signals in the range +/- 10 mV from a floating source. The noise level at the input is less than 5 mu V (at 100 k Omega input impedance), permitting instantaneous diffuse solar radiation measurements to 0.5 W m(-2) resolution with 12 bit analog to digital conversion. The temperature stability of gain is better than 5 ppm/degrees C (-4 to 20 degrees C). Averaged over a decade of use, the long term drift of the amplifier gain is less than similar to 0.02%/yr. As well as radiometers measuring solar and terrestrial radiations, the amplifier has also been successfully used with low level signals from thermocouples and ground heat flux plates.

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Kites offer considerable potential as wind speed sensors—a role distinct from their traditional use as instrument-carrying platforms. In the sensor role, wind speed is measured by kite-line tension. A kite tether line tension meter is described here, using strain gauges mounted on an aluminum ring in a Wheatstone bridge electronic circuit. It exhibits a linear response to tension 19.5 mV N−1 with good thermal stability mean drift of −0.18 N °C−1 over 5–45 °C temperature range and a rapid time response 0.2 s or better. Field comparisons of tether line tension for a Rokkaku kite with a fixed tower sonic anemometer show an approximately linear tension-wind speed relationship over the range 1–6 ms−1. © 2010 American Institute of Physics. doi:10.1063/1.3465560

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We use geomagnetic activity data to study the rise and fall over the past century of the solar wind flow speed VSW, the interplanetary magnetic field strength B, and the open solar flux FS. Our estimates include allowance for the kinematic effect of longitudinal structure in the solar wind flow speed. As well as solar cycle variations, all three parameters show a long-term rise during the first half of the 20th century followed by peaks around 1955 and 1986 and then a recent decline. Cosmogenic isotope data reveal that this constitutes a grand maximum of solar activity which began in 1920, using the definition that such grand maxima are when 25-year averages of the heliospheric modulation potential exceeds 600 MV. Extrapolating the linear declines seen in all three parameters since 1985, yields predictions that the grand maximum will end in the years 2013, 2014, or 2027 using VSW, FS, or B, respectively. These estimates are consistent with predictions based on the probability distribution of the durations of past grand solar maxima seen in cosmogenic isotope data. The data contradict any suggestions of a floor to the open solar flux: we show that the solar minimum open solar flux, kinematically corrected to allow for the excess flux effect, has halved over the past two solar cycles.

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The total calcium level of raw skimmed milk was reduced by 10, 19, 29, 40 and 51% using Duolite® ion-exchange resin. The products were examined for concentrations of ionic calcium, sodium and potassium and the pH, ethanol stability, micelle diameter and ζ-potential were also measured. Ionic calcium decreased with removal of calcium and pH increased. Calcium removal resulted in an increase in the ethanol stability from 88% to above 100%. Casein micelle diameter increased as calcium was removed. The ζ-potential of the skimmed bulk milk was -24.4 mV, gradually becoming more negative with calcium removal to -30.6 mV after 51% calcium removal. The milk became more translucent as calcium was removed. To investigate the reversibility of this process, calcium chloride was added back to the depleted samples to restore their original total calcium content. At 51% removal, restoration of the total calcium level resulted in formation of clots. At levels of 10 and 19% calcium removal, the ethanol stability remained above 100%, but at higher levels of calcium removal the alcohol stability was adversely affected when the calcium was added back. Adding back calcium resulted in partial restoration of the original casein micelle diameter.

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The reduction of water-insoluble indigo by the recently isolated moderate thermophile, Clostridium isatidis, has been studied with the aim of developing a sustainable technology for industrial indigo reduction. The ability to reduce indigo was not shared with C. aurantibutyricum, C. celatum and C. papyrosolvens, but C. papyrosolvens could reduce indigo carmine (5,5-indigosulfonic acid), a soluble indigo derivative. The supernatant from cultures of C. isatidis, but not from cultures of the other bacteria tested, decreased indigo particle size to one-tenth diameter. Addition of madder powder, anthraquinone-2,6-disulfonic acid, and humic acid all stimulated indigo reduction by C. isatidis. Redox potentials of cultures of C. isatidis were about 100 mV more negative than those of C. aurantibutyricum, C. celatum and C. papyrosolvens, and reached –600 mV versus the SCE in the presence of indigo, but potentials were not consistently affected by the addition of the quinone compounds, which probably act by modifying the surface of the bacteria or indigo particles. It is concluded that C. isatidis can reduce indigo because (1) it produces an extracellular factor that decreases indigo particle size, and (2) it generates a sufficiently reducing potential.