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    A new method for the joint visualization of vascular structures and connective tissues: Corrosion casting and 1 N NaOH maceration

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    Corrosion casting combined with scanning electron microscopy (SEM) has been widely used to study the morphofunctional aspects of microcirculation in many organs. In this study, we present an optimization of the corrosion casting (CC) technique associating it with NaOH 1 N maceration method to obtain a clear visualization of the relationships existing between the microvascular architecture of an organ and its extracellular matrix. Briefly, experiments were performed macerating the tissue previously injected with a low viscosity acrylic resin in 1 N NaOH and then observing it at SEM. In this study, we present an application of this technique to better evaluate the extracellular components of the vascular wall in medium-sized and capillary vessels both in skin and in kidney. The results obtained yielded clear images of the three-dimensional layout of medium-sized and capillary vessels in comparison with the extracellular environment. Furthermore, detailed information was obtained on the three-dimensional layout of fibers constituting the walls of venules, arterioles, and capillaries. In addition, the tubular collagenic structures surrounding the excretory tubules of the kidney and the dermal glands of the skin were depicted and their relationships with their vascular supply described in detail. © 2006 Wiley-Liss, Inc

    Balance assessment after altering stimulation of the neurosensory system

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    Aim Posture requires fine integrative elaboration, performed by the central nervous system, of neurosensory information originated from the visual, vestibular and spinal circuit. Many perturbing agents can influence this elaboration and then the postural stability. Several studies have evaluated only the effect of a single agent on the postural control. The study analysed the perturbing effect of several external agents on the different sensorial circuits in terms of postural balance loss in orthostatism. Methods The postural stability of 31 patients was evaluated with a static posturography platform in basal conditions and after exposure to an external agent in the following order: stroboscopic light projecting, mechanical rotations on a swivel chair, feet desensitization through ice, administration of an alcoholic drink at intervals which depended on the participant return to basic posturographic values. Tests were performed with open eyes (OE), closed eyes (CE) and reducing plantar perception through the use of a rubber pillow. Results The stroboscopic light altered the postural control. The swivel chair disturbed only with CE. Ice and alcohol increased the oscillation area. The alcohol test had a significant reduction in postural control with OE compared to CE. The rubber cushion increased the oscillation area in all OE tests and with CE in alcohol and ice tests. Conclusion The different agents did not trigger postural control deficits in the same way. A cold environment with psychedelic lights and the use of alcoholic beverages altered significantly the postural stability by influencing simultaneously all perceptions (visual, vestibular and somatosensory feedback)

    Gait screening of a population of young, healthy athletes by means of a portable, low-cost device unveils hidden left-right asymmetries in both quadriceps and anterior cruciate ligament forces

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    The present study reports the on-field screening of a population of young soccer players in the pursuit of alterations in gait using a portable and low-cost gait analysis system composed of a Wii Balance Board and a webcam.Objective: The present study reports the on-field screening of a population of young soccer players in the pursuit of alterations in gait using a portable and low-cost gait analysis system composed of a Wii Balance Board and a webcam. Results: Recordings of motion of the lower extremities along with vertical ground reaction force (GRF) were used to quantify coefficients of symmetry for the overall GRF and the forces exerted by the quadriceps femori and acting on the anterior cruciate ligament (ACL). Data show that, in face of a quite homogeneous symmetry of GRF during left and right stance phases of gait, quadriceps and ACL exert and are subjected to left-right asymmetrical forces that might prelude, especially in young athletes, later alterations of gait

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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