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This study investigated contents of training sessions from 387 regular swimmers involved in a recreational workout without supervision. We did use multiple correspondences analysis in order to identify self-trained swimmers typology in a sample from a social networking website, focusing on swimming practice. Self-reported parameters (n = 12) were age, gender, practice frequency, supervision in physical activity experiment, main training target, main reason for swimming choice, swimming session duration and distance, most used swimming stroke and material, quality of the training control, and training evolution during a year. Results have highlighted different training strategies and targets according to gender and age. Male strategy consists in performing higher distance (1818.8 ± 644.5 m vs. 1453.0 ± 603.3, p < 0.05 for male and female respectively) by using several swim stroke and gears involving upper body muscles (front crawl, pull buoy and paddles). More concerned about duration of their sessions, women are mainly using breaststroke. Backstroke is associated with people aged higher than 50. We also have established a connection between motives according to ages and long term strategies. The main motivation for middle aged people appears to be general health benefits by performing identical swimming session without evolution during a year. People aged from 20 to 30 are divided between an identical swimming session strategy and an increase in distance or in intensity strategy during a year. This population appears to be concerned about a global health benefits and a body shape effects. Suggestions are made to improve swimming practice environment during free time sessions according to the main results.

Key Points

  • Male strategy consists in performing higher distance by using several swim stroke and gears involving upper body muscles whereas women are more concerned about effort duration and use breaststroke in majority.
  • The main motivation for middle aged people appears to be general health benefits whereas people aged from 20 to 30 appears to be concerned about a global health benefits and a body shape effects.
  • Excepted middle age people, recreational swimmers have low control quality of their session even if they have a good skill level. This suggests to improve health strategy education and swimming pool environment.
Key words: Physical activity, strategy, multiple correspondence analysis, leisure swimming  相似文献   
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Extracellular L-glutamate poses a severe excitotoxic threat to neurons and glia when unregulated, therefore low synaptic levels of this neurotransmitter must be maintained via a rapid and robust transport system. A recent study from our laboratory showed a reduced glutamate uptake rate in the striatum of the aged Fischer 344 (F344) rat, yet the mechanism underlying this phenomenon is unknown. The current study utilized in vivo electrochemical recordings, immunoblotting and biotinylation in young (6 months), late-middle aged (18 months) and aged (24 months) F344 rats to elucidate the potential role that glutamate transporters (GLT-1, GLAST, and EAAC1) may play in this mechanism. Here we show that the time necessary to clear glutamate from the late-middle aged and aged striatum is significantly prolonged in comparison to the young striatum. In addition, an analysis of various sub-regions of the striatum revealed a marked dorsoventral gradient in terms of glutamate clearance times in the aged striatum, a phenomenon which was not present in the striatum of the animals of the remaining age groups. We also found that the decreased glutamate clearance time observed in the late-middle aged and aged rats is not due to a decrease in the production of total transporter protein among these three transporters. Rather, a significant reduction in the amount of GLAST expressed on the plasma membrane surface in the aged animals (approximately 55% when compared to young rats) may contribute to this phenomenon. These age-related alterations in extracellular l-glutamate regulation may be key contributors to the increased susceptibility of the aged brain to excitotoxic insults such as stroke and hypoxia.  相似文献   
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K-edge digital subtraction angiography (KEDSA), a recently developed synchrotron-based technique, utilizes monochromatic radiation and allows acquisition of high-quality angiography images after intravenous administration of contrast agent. We tested KEDSA for its suitability for intravenous cerebral angiography in an animal model. Adult male New Zealand rabbits were subjected to either angiography with conventional x-ray equipment or synchrotron-based intravenous KEDSA, using an iodine-based contrast agent. Angiography with conventional x-ray equipment after intra-arterial administration of contrast agent demonstrated the major intracranial vessels but no smaller branches. KEDSA was able to visualize the major intracranial vessels as well as smaller branches in both radiography mode (planar images) and tomography mode. Visualization was achieved with as little as 0.5 ml kg-1 of iodinated contrast material. We were able to obtain excellent visualization of the cerebral vasculature in an animal model using intravenous injection of contrast material, using synchrotron-based KEDSA.  相似文献   
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Multiple imaging modalities are required in patients receiving cardiac resynchronization therapy. We have developed a strategy to integrate echocardiographic and angiographic information to facilitate left ventricle (LV) lead position. Full three-dimensional LV-volumes (3DLVV) and dyssynchrony maps were acquired before and after resynchronization. At the time of device implantation, 3D-rotational coronary venous angiography was performed. 3D-models of the veins were then integrated with the pre- and post-3DLVV. In the case displayed, prior to implantation, the lateral wall was delayed compared to the septum. The LV lead was positioned into the vein over the most delayed region, resulting in improved LV synchrony.  相似文献   
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Background

For patients undergoing liver resection that leaves an empty intraparenchymal cavity, traditional topical agents might be inadequate to achieve additional hemostasis. A new hemostatic expanding topical foam (BioFoam®) has been designed to provide a mechanical seal. The objective of this study was to report our preliminary results regarding the safety and the efficacy using this foam.

Methods

Between 2009 and 2011, BioFoam® was used to fill a three-dimensional defect following liver resection in 14 patients. The operative results and postoperative course of these patients were compared to those of 14 matched controls who underwent liver resection but did not receive BioFoam®.

Results

The two groups were similar in terms of demographics, indications for liver resection, type of surgical procedure, and type and duration of clamping. BioFoam® patients experienced significantly less operative blood loss (275 vs. 630 ml, p = 0.032) but similar operative transfusion rates (28.6 vs. 35.7 %, p = 0.686) compared to no-BioFoam® patients. The postoperative mortality was nil and no patient developed postoperative hemorrhage. While the two groups shared similar overall (64.3 vs. 57.1 %, p = 0.599) and major (28.6 vs. 14.3 %, p = 0.357) complications rates, BioFoam® patients experienced significantly higher major vascular thrombosis compared to no-BioFoam® patients (29 vs. 0 %, p = 0.04). In the BioFoam® group, major vascular thrombosis was associated with exposure of the vessel along the transection plane.

Conclusion

While the clinical benefit of BioFoam® in high-risk liver resections leaving a deep parenchymal defect remains to be proven, the associated risk of vascular thrombosis should preclude its use in contact with major veins.  相似文献   
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