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《EMC - Radiologie》2005,2(4):413-456
Imaging of normal and pathologic trachea at the thoracic and cervical levels is described extensively. Beside congenital abnormalities discovered in adulthood, acquired tracheal abnormalities are artificially divided in two subgroups. One group consists of diffuse abnormalities, with all but one diseases associated with a diffuse narrowing of the tracheal lumen. The other group comprises focal abnormalities that lead to tracheal stenoses of various lengths, with a postintubation stenosis as probably the most frequent cause, followed by tumours. The main modality for tracheal imaging is now multidetector-row spiral CT. This technique allows for faster volume coverage and higher spatial and temporal resolution. The improved spatial resolution impacts on both axial images and all reconstructions techniques that have become indispensable for interpretation of a vertical structure such as the trachea. Chest X-ray is no longer the frontline imaging technique. MRI has not yet reached all its potential as compared to CT.  相似文献   

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Sans résuméVortrag, gelegentlich der Tagung der Deutschen Gesellschaft für gerichtliche und soziale Medizin in München 1952.  相似文献   

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《Science & Sports》2003,18(3):166-168
Aim. – Study was to asses the heart rate variability related to the physical practice intensity in post menopausal women.Method. – Time domain measurement of heart rate variability has been realised from the electrocardiogram at rest and during exercice in 3 groups of 6 women : untrained, active and trained. At rest, no significant difference betwen groups appears. But, in the standing position, RR interval and the dispersion around RR interval decrease in trained group only. During submaximal exercise, this dispersion is more elevated in active and trained groups.Conclusion. – Physical practice induces a higher response of sinus node to vagal modulation during standing position and submaximal exercise.  相似文献   

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《Science & Sports》2003,18(3):141-149
Purpose. – This study presents a new method for determining the resultant braking force during wheelchair displacement and investigates the respective effects of the level and the distribution of the system’s mass.Method and results. – A three-dimensional accelerometer was fixed directly under the seat of wheelchair and was used to measure the deceleration of the mass-and-wheelchair’s system. Three masses (50, 70 and 90 kg) were laid on a support in 3 positions corresponding to three distributions (10, 40 and 70%) of the system’s total mass upon the front casters. A series of 15 deceleration trials was performed for each of the 9 combinations. Statistical results showed that the system’s deceleration was mainly explained by the mass distribution upon the front casters (92%) and in the least by the system’s total mass (8%).Conclusion. – Considering the fore-and-aft movements of the subject’s centre of mass during wheelchair locomotion, the results of this study let us assume that the resultant braking force does not remain constant along the propulsion cycle. Moreover, the present method could be used to investigate the influence of wheelchair’s adjustments and floor’s characteristics on the resultant braking force.  相似文献   

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