BACKGROUND:Arterialized venous flaps (AVFs) have been used for reconstruction of soft tissue defects throughout the body. Several different revascularization models have been performed, but venous ...drainage through the arterial system has not been studied. In our total retrograde reverse blood flow (TRRBF) perfusion model, the arterial blood flow enters through the venous system and venous drainage exits through the arterial system.
METHODS:We developed a novel experimental model in rabbit ears to evaluate the capacity of TRRBF perfusion pattern to allow AVF viability. The ears were assigned to 3 groupsgroup 1, total devascularization without revascularization (n = 3); group 2, TRRBF (n = 12); and group 3, conventional AVF (n = 12). The ears were observed during a 30-day follow-up period, and clinical serial assessment of edema, cyanosis, and necrosis was performed. Tissue oxygenation was determined at the beginning and end of the follow-up. Histological analysis was performed.
RESULTS:Necrosis was found in 3/3 (100%) ears in group 1, 3/12 (25%) in group 2, and 0/12 (0%) in group 3 (95% CI, 0.505–0.994; P = 0.0001). In group 2, edema was higher (5/12, 41.66%) than in group 3 (0/12, 0%) (95% CI, 0.0135–0.65; P = 0.041). Cyanosis and venous congestion was of greater intensity and duration in group 2 than in group 3 (10.33 ± 4.51 vs 4.5 ± 2.06 d).
CONCLUSIONS:Although evolution is torpid and prolonged in ears with TRRBF, 9/12 (75%) survived, suggesting that TRRBF can be used as a rescue method.
Rural surgery networks: need for a home Iglesias, Stuart, MD; Kornelsen, Jude, PhD; Woollard, Robert, MD ...
Canadian journal of rural medicine,
09/2015, Letnik:
20, Številka:
4
Journal Article
Background Time to treatment remains the most important factor in acute ischemic stroke prognosis. We quantified the effect of new interventions reducing in-hospital delays in acute stroke management ...and assessed its repercussion on door-to-imaging (DTI), imaging-to-needle (ITN), and door-to-needle (DTN) times. Methods Prospective registry of consecutive stroke patients who were candidates for reperfusion therapy attended in a tertiary care hospital from February 1 to December 31, 2014. A series of measures aimed at reducing in-hospital delays were implemented. We compared DTI, ITN, and DTN times between patients who underwent the interventions and those who did not. Results 231 patients. DTI time was lower when personal history was reviewed and tests were ordered before patient arrival (2.5 minutes saved, P = .016) and when electrocardiogram was not made (5.4 minutes saved, P < .001). Not performing a computed tomography angiography and not waiting for coagulation results from laboratory before intravenous thrombolysis (25.5%) reduced ITN time significantly (14 and 12 minutes saved, respectively, P < .001). These interventions remained as independent predictors of a shorter ITN and DTN time. Completing all steps resulted in the lowest DTI and ITN times (13 and 19 minutes, respectively). Conclusions Every measure is an important part of a chain focused on saving time in acute stroke: the lowest DTI and ITN times were obtained when all steps were completed. Measures shortening ITN time produced a greater impact on DTN time reduction; therefore, ITN interventions should be considered a critical part of new protocols and guidelines.
The aim of this study was to examine the procedural knowledge level in young volleyball players and to establish the relationship between procedural knowledge, experiencie and performance, being the ...performance the championship positions obtained at the end of the competition. Participants in the study were 110 male young players of the regional teams that disputed the Spain Champioship in Cáceres in june of 2005, and with 1 to 6 years of volleyball experience. The variables of this study were proceedural knowledge, experience in organised volleyball, experience in unorganised volleyball and performance (championship position). Procedural knowledge was measured by the volleyball players by means of "volleyball procedural knowledge test" (Moreno, 2006). The results revealed the lineal and significative relationship between procedural knowledge, experience in organised volleyball and performance, indicating that high-procedural knowledge and experience in organised volleyball exhibited high-championship position. Regression analysis indicated that experience in organised volleyball and procedural knowledge were the main predictor of performance. These findings are discussed with previous researchs.
El objetivo de nuestro estudio fue conocer el nivel de conocimiento procedimental de jugadores de voleibol de categoría cadete y establecer la relación existente entre ese conocimiento, la experiencia y el rendimiento en el juego, entendido éste como la posición final en la clasificación del campeonato. La muestra estuvo compuesta por un total de 110 jugadores de categoría cadete masculina, todos ellos pertenecientes a equipos autonómicos que participaron en el Campeonato de España celebrado en Cáceres en junio de 2005, y con una experiencia en voleibol de entre 1 y 6 años. Las variables de nuestro estudio fueron el conocimiento procedimental, la experiencia en voleibol federado, la experiencia en voleibol sin competición reglada y el rendimiento (posición final en la clasificación). Se midió el nivel de conocimiento procedimental de cada uno de los jugadores a través del "cuestionario de conocimiento procedimental para voleibol" (Moreno, 2006). Los resultados obtenidos determinaron la existencia de una relación lineal y significativa entre el conocimiento procedimental, la experiencia en voleibol federado y el rendimiento, de manera que a mayor conocimiento y experiencia en competición reglada, mejor es la posición que ocuparon en la clasificación final. El análisis de regresión realizado determinó que la experiencia en voleibol federado y el conocimiento procedimental eran variables que predecían un mayor rendimiento en juego. Diversas investigaciones desarrolladas en esta línea apoyan estos resultados.
In this work it is reviewed the most novel advances in the multipactor RF breakdown risk assessment devoted to RF satellite microwave passive devices employed in space telecommunication systems. On ...one side, it is studied the effect of transmitting a single-carrier digital modulated signal in the multipactor RF voltage threshold in a coaxial line. On the other hand, an analysis of the multipactor phenomenon in a parallel-plate waveguide containing a magnetized ferrite slab it is presented.
Objective We sought to determine the overall effectiveness and risk factors for failure of hydrothermal ablation in the management of abnormal uterine bleeding. Study Design We performed a ...retrospective cohort analysis of patients who underwent hydrothermal ablation for abnormal uterine bleeding at our institution from July 2005 through February 2008. Variables analyzed included patient demographics, insurance status, body mass index, bleeding pattern, obstetric history, prior medical therapy and duration, uterine characteristics, and tobacco use history. Results In all, 159 patients were identified and 142 charts were eligible for evaluation. A total of 45 patients (31.6%) had return of preablation vaginal bleeding. Menometrorrhagia was a significant predictor for failure ( P = .027) and subsequent hysterectomy ( P = .0025). Younger age ( P = .044), tobacco use ( P = .042), and Medicaid/Medicare insurance status ( P = .039) were also associated with a higher risk of failure. Conclusion Women who are younger, use tobacco products, and have menometrorrhagia are more likely to fail hydrothermal ablation.
Debris disks are the natural by-products of the planet formation process. Scattered or polarized light observations are mostly sensitive to small dust grains that are released from the grinding down ...of bigger planetesimals. High angular resolution observations at optical wavelengths can provide key constraints on the radial and azimuthal distribution of the small dust grains. These constraints can help us better understand where most of the dust grains are released upon collisions. We present SPHERE/ZIMPOL observations of the debris disk around HR 4796 A, and model the radial profiles along several azimuthal angles of the disk with a code that accounts for the effect of stellar radiation pressure. This enables us to derive an appropriate description for the radial and azimuthal distribution of the small dust grains. Even though we only model the radial profiles along (or close to) the semi-major axis of the disk, our best-fit model is not only in good agreement with our observations but also with previously published datasets (from near-IR to sub-mm wavelengths). We find that the reference radius is located at \(76.4\pm0.4\) au, and the disk has an eccentricity of \(0.076_{-0.010}^{+0.016}\), with the pericenter located on the front side of the disk (north of the star). We find that small dust grains must be preferentially released near the pericenter to explain the observed brightness asymmetry. Even though parent bodies spend more time near the apocenter, the brightness asymmetry implies that collisions happen more frequently near the pericenter of the disk. Our model can successfully reproduce the shape of the outer edge of the disk, without having to invoke an outer planet shepherding the debris disk. With a simple treatment of the effect of the radiation pressure, we conclude that the parent planetesimals are located in a narrow ring of about \(3.6\) au in width.
Endoscopic ultrasound (EUS) represents an advance in the diagnosis and staging of several diseases. EUS-guided fine-needle aspiration is useful, but technically demanding, and can be associated with ...complications. Elastography emerges as a useful tool that is based on the knowledge that some diseases, like cancer, lead to a modification in tissue stiffness. Elastography evaluates the elastic properties of tissues and compares images obtained before and after compression to target tissues; differentiating benign from malignant lesions. This article reviews theoretical aspects and the methodology of EUS elastography. Clinical applications, mainly in pancreatic diseases and lymph nodes, are analyzed.
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