3,787 research outputs found

    Imagerie des fistules arterio-veineuses durales a drainage veineux peri -medullaire

    Get PDF
    Les fistules durales rachidiennes à drainage veineux périmédullaire constituent une pathologie d’individualisation récente. C’est les plus fréquentes des malformations vasculaires vertébromédullaires,elles se présentent sous la forme d’une myélopathie spastique progressive chez un sujet de plus de 40 ans. A partir d’une étude rétrospective des données cliniques et explorations radiologiques d’une série de 11 cas en IRM et artériographie médullaire, nous avons recensé l’ensemble des signes radiologiques qui orientent le diagnostic. L’IRM a montré un hypersignal T2 centromédullaire de façon constante ainsi que des vaisseaux périmédullaires pathologiques. L’angiographie médullaire reste l’examen clé pour le diagnostic. Elle a permit de montrer dans dix cas le shunt artério-veineux ainsi que ses afférences artériels et son retour veineux, permettant de planifier le traitement. Huit patients ont été pris en charge chirurgicalement avec exclusion de la fistule suivie d’une amélioration clinique. L’imagerie joue aussi un rôle important dans le suivi postthérapeutique. L’IRM permet de mettre en évidence la disparition progressive des anomalies initiales, signede l’efficacité du traitement. Les fistules artério-veineuses à drainage veineux périmédullaire sont une pathologie qui reste encore méconnue. La connaissance de tous ces éléments d’imagerie est fondamentalepour un diagnostic et une prise en charge précoces, seuls garants d’une bonne évolution après traitement

    Peltier Effect Applied to the Design and Realization of a New Mass Flow Sensor

    Get PDF
    The present paper deals with design and realization of a new mass flow sensor using the Peltier effect. The sensor, shaped as a bimetallic circuit includes two continuous parallel strips coated with a great deal of metal plated spots. In such a device, one track performs as a classical thermoelectrical circuitry whose both plated and uncoated parts provide the thermopile junctions. The other strip is subjected to electrical current so as to generate numerous small thermal gradients owing to the Peltier effect. Then, the resulting differences in temperature induce a Seebeck e.m.f. detected by the other strip acting as a receiver. The thermal coupling between transmitter and receiver tracks depends on many variation of the surrounding environment heat transfer coefficient. Therefore, such a device allows us to detect any shift in physical properties related to the apparent thermal conductivity. In special case of a steady state fluid, the induced e.m.f. in the receiving track hinges on the thermal conductivity. When the fluid is in relative motion along the sensor, the velocity can be read out as a funotion of voltage as an application, the sensor is placed into a tube conducting a fluid flow, in order to design a new mass flowmeter

    Relaxable Damage in Hot-Carrier Stressing of n

    Get PDF
    A method for device characterization is experimented to qualify the relaxable damage in hot-carrier stressing of n-MOS transistors. The degradation of physical parameters of the body-drain junction of power HEXFETs is presented for applied stress condition Vg= Vd/2. Large decrease of the resistance series, of the ideality factor, and of the reverse recombination current are shown to be related to relaxation time, and are significant at Vg=–Vd. These effects are discussed and explained by the evolution of the interface states

    Leucémie aigüe myélomonocytaire à éosinophiles révélée par une pancréatite aigüe

    Get PDF
    La leucémie aigüe myélomonocytaire à composante éosinophile (LAM4eo) est une hémopathie maligne rare, caractérisée par une prolifération blastique myéloïde avec présence d'une composante monocytaire et des éosinophiles anormaux. Elle est associée à l'inversion du chromosome 16,parfois à sa variante la translocation (16;16).Nous rapportons un cas de LAM4eo chez un patient de sexe masculin âgé de 51 ans, découverte audécours d'un bilan paraclinique pour pancréatite aiguë (PA) confirmée par la TDM. L'hémogramme a montré une hyperleucocytose à 123G/l faitede 60% de blastes, une monocytose à 5 G/L ainsi qu'une lignée  éosinophile dystrophique. Le myélogramme a objectivé l'infiltration de la moelle par une population blastique estimée à 61% d'expression hétérogène à la Cytométrie de flux : Des blastes très immatures  exprimant fortement les marqueurs CD117 et CD34 ; des blastes  prédominants qui expriment les antigènes CD33, CD13, CD65  (myéloblastes). Et une partie des blastes, était positive pour le CD14, CD4, CD11c (monoblastes).Après une exploration étiologique approfondie n'ayant pas pu trouver un lien de cause à effet, l'association entre les deux pathologies a été considérée comme fortuite et la pancréatite a été rattachée à la prise de paroxétine. Le patient a été mis alors en condition, et a été traité par chimiothérapie avec bonne évolution clinique et  biologique

    Giant fibroadenoma of the breast in late third trimester

    Get PDF
    Giant fibroadenomas (GFs) occurring during pregnancy are extremely rare, and only a few cases have been reported. Although it is a benign condition, it often requires biopsy or even surgery to exclude malignancy. The authors report a new case of GF in a 29‑year‑old pregnant woman with a family history of breast cancer. She presented at 37 weeks of gestation with a large mass in her left breast. Tru‑cut biopsy was suggestive of fibroadenoma. After delivery, enucleation of the mass was performed, and histology confirmed the previous diagnosis. Benign neoplasms should be suspected in any pregnant woman with a rapidly enlarging breast mass. Early surgical excision should be offered as a standard treatment to avoid structural damage to the breast and the need for reconstructive surgery.Keywords: Breast mass; giant fibroadenoma; pregnancy; Tru‑cut biops

    Clinical Presentation and Time-Based Mortality in Patients With Chest Injuries Associated With Road Traffic Accidents

    Get PDF
    Background: Blunt chest trauma (BCT) poses significant morbidity and mortality worldwide. Objectives: We investigated the clinical presentation and outcome of BCT related to road traffic accidents (RTA). Patients and Methods: A retrospective observational analysis for patients who sustained BCT secondary to RTA in terms of motor vehicle crash (MVC) and pedestrian-motor vehicle accidents (PMVA) who were admitted to the trauma center at Hamad general hospital, Doha, Qatar, between 2008 and 2011. Results: Of 5118 traumatic injury cases, 1004 (20%) were found to have BCT secondary to RTA (77% MVC and 23% PMVA). The majority were males (92%), and expatriates (72%). Among MVCs, 84% reported they did not use protective devices. There was a correlation between chest abbreviated injury score (AIS) and injury severity scoring (ISS) (r = 0.35, r2 = 0.12, P < 0.001). Regardless of mechanism of injury (MOI), multivariate analysis showed that the head injury associated with chest AIS and ISS was a predictor of mortality in BCT. Overall mortality was 15%, and the highest rate was observed within the first 24 hours post-trauma. Conclusions: Blunt chest trauma from RTA represents one-fifth of the total trauma admissions in Qatar, with a high overall mortality. Pedestrians are likely to have more severe injuries and higher fatality rates than MVC victims. Specific injury prevention programs focusing on road safety should be implemented to minimize the incidence of such preventable injuries

    Hadronic shift in pionic hydrogen

    Get PDF
    The hadronic shift in pionic hydrogen has been redetermined to be ϵ1s=7.086 ± 0.007(stat) ± 0.006(sys)\epsilon_{1s}=7.086\,\pm\,0.007(stat)\,\pm\,0.006(sys)\,eV by X-ray spectroscopy of ground state transitions applying various energy calibration schemes. The experiment was performed at the high-intensity low-energy pion beam of the Paul Scherrer Institut by using the cyclotron trap and an ultimate-resolution Bragg spectrometer with bent crystals.Comment: 10 pages, 6 figure

    FROM THE ATLAS TO THE RIF A CRUSTAL SEISMIC IMAGE ACROSS MOROCCO

    Get PDF
    The velocity structure of the crust and the geometry of the Moho across Morocco has been the main target of two recently acquired wide-angle seismic reflection transects. One is the SIMA experiment which provided seismic constraints beneath the Atlas Mountains and the second has been the RIFSEIS experiment which sampled the RIF orogen. Jointly these controlled source wide-angle seismic reflection data results in an almost 700 km, seismic profile going from the the Sahara craton across the High and Middle Atlas and Rif Mountain till the Gibraltar-Arc (Alboran). Current work on the interpretation of the seismic data-set is based on forward modeling, ray-tracing, as well as low fold wide-angle stacking. The data has resulted in a detailed crustal structure and velocity model for the Atlas Mountains and a 700 km transect revealing the irregular topography of the Moho beneath these two mountain orogens. Results indicate that the High Atlas features a moderate crustal thickness and that shortening is resolved at depth through a crustal root where the Saharan crust under-thrusts below the Moroccan crust, defining a lower crust imbrication which locally places the Moho boundary at, approximately, 40 km depth. The P-wave velocity model is characterized, in averaged, by relatively low velocities. These low deep crustal velocities together with other geophysical observables such as: conductivity estimates derived from Mt measurements; moderate Bouguer gravity anomaly; surface exposures of recent alkaline volcanics; lead the interpretation to propose that partial melts are currently emplaced in the deep crustal levels and in the upper mantle. The Moho discontinuity defines a crust which is in average relatively thin beneath the Atlas which is almost a 4000 m high orogenic belt. The resulting model supports existence of mantle upwelling as a possible mechanism that contributes, significantly, to maintain the High Atlas topographyPeer Reviewe

    Design and Realization a New Thermoelectric Sensor, Application

    Get PDF
    The present paper deals with design and realization of a New thermoelectric sensor adapted to conceive a circuit breaker, using the thermoelectric effects (Joule, Peltier and Seebeck). The sensor includes two printed circuits. The first is constituted of two resistive tracks of constantan, it is the transmitting circuit. The second, a planar thermoelectric circuit acting as a receiver, is constituted of many plated differential thermocouples. The transmitting circuit is placed on the top surface of the receiver circuit so that the resistive tracks are placed on the levels of thermoelectric junctions. The measuring method consists to passing electrical currents through the resistive tracks in order to generate temperature gradients between junction points of the bimetallic circuit. Then the resulting temperature differences between junction points is directly converted into a proportional Seebeck voltage. As an application, the sensor is adapted to realize a differential circuit-breaker with a low difference current
    • …
    corecore