980 resultados para anatomy
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Des efforts de recherche considrables ont t dploys afin d'amliorer les rsultats de traitement de cancers pulmonaires. L'tude de la dformation de l'anatomie du patient cause par la ventilation pulmonaire est au coeur du processus de planification de traitement radio-oncologique. l'aide d'images de tomodensitomtrie quadridimensionnelles (4DCT), une simulation dosimtrique peut tre calcule sur les 10 ensembles d'images du 4DCT. Une mthode doit tre employe afin de recombiner la dose de radiation calcule sur les 10 anatomies reprsentant une phase du cycle respiratoire. L'utilisation de recalage dformable d'images (DIR), une mthode de traitement d'images numriques, gnre neuf champs vectoriels de dformation permettant de rapporter neuf ensembles d'images sur un ensemble de rfrence correspondant habituellement la phase d'expiration profonde du cycle respiratoire. L'objectif de ce projet est d'tablir une mthode de gnration de champs de dformation l'aide de la DIR conjointement une mthode de validation de leur prcision. Pour y parvenir, une mthode de segmentation automatique base sur la dformation surfacique de surface t cre. Cet algorithme permet d'obtenir un champ de dformation surfacique qui dcrit le mouvement de l'enveloppe pulmonaire. Une interpolation volumtrique est ensuite applique dans le volume pulmonaire afin d'approximer la dformation interne des poumons. Finalement, une reprsentation en graphe de la vascularisation interne du poumon a t dveloppe afin de permettre la validation du champ de dformation. Chez 15 patients, une erreur de recouvrement volumique de 7.6 2.5[%] / 6.8 2.1[%] et une diffrence relative des volumes de 6.8 2.4 [%] / 5.9 1.9 [%] ont t calcules pour le poumon gauche et droit respectivement. Une distance symtrique moyenne 0.8 0.2 [mm] / 0.8 0.2 [mm], une distance symtrique moyenne quadratique de 1.2 0.2 [mm] / 1.3 0.3 [mm] et une distance symtrique maximale 7.7 2.4 [mm] / 10.2 5.2 [mm] ont aussi t calcules pour le poumon gauche et droit respectivement. Finalement, 320 51 bifurcations ont t dtectes dans le poumons droit d'un patient, soit 92 10 et 228 45 bifurcations dans la portion suprieure et infrieure respectivement. Nous avons t en mesure d'obtenir des champs de dformation ncessaires pour la recombinaison de dose lors de la planification de traitement radio-oncologique l'aide de la mthode de dformation hirarchique des surfaces. Nous avons t en mesure de dtecter les bifurcations de la vascularisation pour la validation de ces champs de dformation.
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En 2011, cinq (5) cultivars de saules ont t slectionns pour leur rendement en biomasse. Ils ont t plants sur quatre sites de la province du Qubec et ont t maintenus selon le protocole de la culture intensive sur courtes rotations (CICR) afin de dterminer leur potentiel pour la bionergie dans des environnements contrasts. La composition et lanatomie du bois de ces cultivars ont t caractrises et compars en fonction des conditions environnementales caractristiques de chaque site. La hauteur et le diamtre la base des plantes diffrent selon les sites. Ainsi, les cultivars rpondent de faon spcifique aux conditions pdoclimatiques dans lesquelles ils sont cultivs. Leffet de lenvironnement na pas t mis en vidence sur la teneur en lignine des cultivars. Cependant, un effet gnotypique a pu tre constat soulignant limportance de la slectivit des cultivars. La densit du bois a tonnamment conserv la mme hirarchie gnotypique entre les sites. loppos, lanatomie du bois prsente des diffrences notamment au niveau des caractristiques des fibres et des vaisseaux. Une forte teneur en polyphnols ainsi que des fibres moins larges et des vaisseaux plus nombreux ont t observs sur le site dont le bois est le plus dense supposant leffet probable dun stress abiotique. De plus, deux fois plus de fibres glatineuses, fibres riches en cellulose, ont t identifies sur ce site montrant un intrt pour la production de biothanol.
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Les approches arthroscopiques et lanatomie normale des articulations antbrachiocarpienne, carpienne moyenne et tarsocrurale nont jamais t dcrites spcifiquement chez les bovins. Notre tude avait pour buts de dfinir les abords chirurgicaux et de dcrire lanatomie arthroscopique de ces trois articulations. Deux carpes et deux tarses issus du cadavre frais dune vache adulte ont t injects avec un mlange de latex, puis dissqus afin de dterminer les sites arthroscopiques dintrt. Par la suite, larthroscopie des articulations antbrachiocarpienne et carpienne moyenne (approche dorsale) et de larticulation tarsocrurale (approches dorsale et plantaire) a t ralise sur six cadavres frais de vaches adultes ne prsentant ni boiterie ni distension articulaire avant leur euthanasie. Les approches dorsolatrale et dorsomdiale des articulations antbrachiocarpienne et carpienne moyenne ont t ralises de part et dautre de lextenseur radial du carpe. Les structures observes taient le radius distal, les os radial, intermdiaire, ulnaire, II et III fusionns et IV du carpe, ainsi que des ligaments palmaires. Les approches dorsolatrale et dorsomdiale de larticulation tarsocrurale ont t ralises latralement au long extenseur des doigts et mdialement au troisime pronier respectivement. Les approches plantarolatrale et plantaromdiale ont t ralises latralement au flchisseur latral des doigts et latralement au flchisseur mdial des doigts respectivement. Les structures observes taient le tibia distal, les trochles proximale et plantaire du talus, le processus coracode du calcanus, larticulation fibulo-calcanenne et des ligaments articulaires. Quelle que soit larticulation, lapproche latrale tait prfre lapproche mdiale. Larthroscopie du carpe et du tarse pourra tre propose dans un contexte hospitalier comme outil diagnostique, thrapeutique et pronostique des maladies articulaires bovines.
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Introduction: Aboriginal peoples are underrepresented within the healthcare professions, and recruitment of Aboriginal students has become a priority for medical schools in Canada. Because of very low high-school completion rates among youth living on-reserve, the Universit de Montrals Faculty of Medicine launched in 2011 the Mini-cole de la sant, a program where health sciences students visit aboriginal schools. Through activities and games, students introduce children to the discovery of health professions. In 2014, the Health Library joined the project with the development of a science books collection for the school libraries and by having a librarian participate in the school visits. Description: In collaboration with the two Atikamekw elementary schools to be visited in 2014, 70 children books on science, human anatomy and the health professions were selected and purchased for each school by the Health Library. A librarian joined the health sciences students during the schools visits and the book collection was integrated in the activities organised during the day. The books were afterwards donated to the school library. Outcomes: Children, school teachers and administrators greatly appreciated the collection. The books were integrated in the library school collections or in the classrooms collections. Discussion: Quality school libraries play an important role in student learning, and access to science and health sciences books could enhance childrens interest for the health professions. By participating in this project, the library is supporting the Health sciences faculties in achieving their goal of reaching out to Aboriginal children and making them aware that a career in health sciences is possible for them. The collaboration has been successful and will be pursued: the Health library will work with the high schools in the same Atikamekw communities to develop science book collections and the schools will be visited in 2015. A Masters in Library and Information Science student will be joining the Mini-cole. Upgrading all donated collections is planned as well.
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En chirurgie vasculaire, laccs lartre fmorale, quil soit par une incision chirurgicale ou par une approche percutane, est trs frquemment utilis pour une multitude dinterventions vasculaires ou endovasculaires; pour des pontages divers, le traitement docclusions artrielles, la rparation danvrismes et la pose dendoprothses. Lobjectif gnral de ce projet de recherche est de faciliter et rduire les risques des approches de lartre fmorale par une meilleure comprhension anatomique du triangle fmoral. La mthodologie a t ralise grce lutilisation de cadavres spcialement embaums par la mthode dveloppe par Walter Thiel. Les rsultats prsents dans ce mmoire ont permis de proposer des solutions en rponse des problmes cliniques en chirurgie vasculaire. Dans un premier temps, ltude de la vascularisation cutane du triangle fmoral a men proposer de nouvelles incisions chirurgicales afin de limiter la dvascularisation cutane des plaies et ainsi rduire les problmes de cicatrisation observs. Ensuite, nous avons valid lidentification radiographique et chographique de lartre fmorale son croisement avec le ligament inguinal afin de faciliter lidentification dun site de ponction artrielle adquat. Enfin, nous avons dvelopp une mthode chographique simple qui facilite lapproche percutane de lartre fmorale, mme chez les patients obses. Les retombes de ce projet de recherche sont multiples pour les cliniciens, ltude fournit une meilleure comprhension anatomique tridimensionnelle du triangle fmoral et les techniques proposes dans ce mmoire pourront apporter une amlioration de la pratique chirurgicale et faciliter le travail des mdecins. Toutefois, ces propositions devront maintenant tre valides en clinique.
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Le foie est un organe vital ayant une capacit de rgnration exceptionnelle et un rle crucial dans le fonctionnement de lorganisme. Lvaluation du volume du foie est un outil important pouvant tre utilis comme marqueur biologique de svrit de maladies hpatiques. La volumtrie du foie est indique avant les hpatectomies majeures, lembolisation de la veine porte et la transplantation. La mthode la plus rpandue sur la base d'examens de tomodensitomtrie (TDM) et d'imagerie par rsonance magntique (IRM) consiste dlimiter le contour du foie sur plusieurs coupes conscutives, un processus appel la segmentation. Nous prsentons la conception et la stratgie de validation pour une mthode de segmentation semi-automatise dveloppe notre institution. Notre mthode reprsente une approche base sur un modle utilisant linterpolation variationnelle de forme ainsi que loptimisation de maillages de Laplace. La mthode a t conue afin dtre compatible avec la TDM ainsi que l' IRM. Nous avons valu la rptabilit, la fiabilit ainsi que lefficacit de notre mthode semi-automatise de segmentation avec deux tudes transversales conues rtrospectivement. Les rsultats de nos tudes de validation suggrent que la mthode de segmentation confre une fiabilit et rptabilit comparables la segmentation manuelle. De plus, cette mthode diminue de faon significative le temps dinteraction, la rendant ainsi adapte la pratique clinique courante. Dautres tudes pourraient incorporer la volumtrie afin de dterminer des marqueurs biologiques de maladie hpatique bass sur le volume tels que la prsence de statose, de fer, ou encore la mesure de fibrose par unit de volume.
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Ralis en cotutelle avec Aix Marseille Universit.
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The present study deals with a general introduction which outlines the objective of the study providing an exhaustive review of works on crabs with particular reference to deep-sea forms. In the first section, Taxonomy and Geographical disribution of the crab are dealt with. The species is described in detail based on several male and female specimens obtained from the pelagic and bottom collections, and its identity in Indian waters is established. It is also distinguished from a closely allied species so far not reported from Indian waters. The second section comprises the biology of the species and it is dealt with under four subheading, namely Habit and Habitats, Reproduction, Food and feeding and Proximate composition. The different habitats occupied by juveniles, subadults and adults of the species have been described and discussed in the light of available information on differential distribution of other related species. The reproductive biology is described in various details touching on gross anatomy and histology of the reproductive systems, spermatogenesis, oogenesis, size at maturity, ovarian maturation process, fecundity, egg carriage and breeding. The food and feeding habits of the species have been studied with reference to the different life stages such as juveniles, subadults and adults during the different phases of life based on stomach content analysis. The percentage of meat recovery and protein, carbohydrate and lipid content of meat have been described in the section dealing with proximate composition. In section three the distribution and abundance of the crab for the entire Indian EEZ and some contiguous ares have been described and illustrated in detail separately for pelagic and benthic realms. The size frequency disrtibution, sex ratios, length weight relationship and relative abundance of breeding population in the experimental catches have been dealt with in detail and discussed.
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Science is search for the laws of underlying phenomena of the nature. Engineering constructs the nature as we wish. Interestingly the huge engineering infrastructure like world wide web has grown in such a complex structure such that we need to see the fundamental science behind the structure and behaviour of these networks. This talk covers the science behind the complex networks like web, biological, social etc. The talk aim to discuss the basic theories that govern the static as well as the dynamics of such interesting networks
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Wheat as the major cereal crop in Egypt is the core of the government's food security policy. But there are rapid losses of the genetic resources of the country as a result of ongoing modernization and development. Thus we compiled the largest possible number of Egyptian accessions preserved in the world gene banks. In the present study we collected nearly 1000 Egyptian wheat accessions. A part from the Triticum species of the Egyptian flora four species have been found, which were recorded for the first time T. turanicum, T. compactum, T. polonicum and T. aethiopicum. To classify the Egyptian wheat species using morphological studies, 108 accessions were selected. Thereafter, these accessions were cultivated and evaluated morphologically to confirm the validity of the classified species. During the morphological evaluation study, a new case was noticed for the number of glumes in one of the Egyptian wheat accessions. Three glumes per spikelet were observed in a branched spike. This led us to assess the phenomenon in all varieties with branching spikes within the genus Triticum. All varieties which have branching spikes at least in some spikletes have three glumes. We considered the case of the third glume as indicator for the domestication syndrome. Also, a new case of other forms of branching in the genus Triticum was investigated, which was a compromise between true and false-branching. We called it true-false branching. Comparative anatomical studies were carried out between Egyptian Triticum species to investigate the possibility of using anatomical features to classify the Egyptian wheat species. It was concluded that it is difficult to use anatomical features alone to differentiate between two Triticum species, especially when they belong to the same ploidy level. A key for the identification of Egyptian Triticum taxa was established.
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Im Rahmen der vorliegenden Arbeit wird ein Verfahren vorgestellt und untersucht, mit welchem Frchte annhernd verlustfrei und unter sehr hygienischen Bedingungen geschnitten werden knnen. Die Produkte hier gezeigt am Beispiel von pfeln und Melonen werden mit einem Hochdruckwasserstrahl geschnitten, der durch ein bildverarbeitendes System entsprechend der Anatomie der Frucht gefhrt werden kann. Die Vorteile dieses Verfahrens sind die individuelle Schnittfhrung, die Materialverluste minimiert und die Tatsache, dass die Frucht ohne wesentlichen Eingriff von Personal bearbeitet wird. Die Literaturauswertung ergab, dass diese Technologie bislang noch nicht bearbeitet wurde. Der Einsatz des Hochdruckwasserstrahlschneidens im Bereich der Agrartechnik beschrnkte sich auf das Schneiden von Zuckerrben Brser [2008], Ligocki [2005] bzw. Kartoffeln Becker u. Gray [1992], das Zerteilen von Fleisch Bansal u. Walker [1999] und Fisch Lobash u. a. [1990] sowie die Nutzung von Wasserstrahlen im Zusammenhang mit der Injektion von Flssigdnger in Ackerbden Niemoeller u. a. [2011]. Ziel dieser Arbeit war es daher, die Einsatzmglichkeiten des Wasserstrahlschneidens zu erfassen und zu bewerten. Dazu wurden in einer Vielzahl von Einzelversuchen die Zusammenhnge zwischen den Prozessparametern wie Wasserdruck, Dsendurchmesser, Vorschubgeschwindigkeit und Dsenabstand auf das Schnittergebnis, also die Rauheit der entstehenden Schnittflche untersucht. Ein Vergleich mit konventionellen Schneidemethoden erfolgte hinsichtlich der Schnittergebnisse und der Auswirkungen des Wasserstrahlschneidens auf nachfolgende Verfahrensschritte, wie dem Trocknen.
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Enhanced reality visualization is the process of enhancing an image by adding to it information which is not present in the original image. A wide variety of information can be added to an image ranging from hidden lines or surfaces to textual or iconic data about a particular part of the image. Enhanced reality visualization is particularly well suited to neurosurgery. By rendering brain structures which are not visible, at the correct location in an image of a patient's head, the surgeon is essentially provided with X-ray vision. He can visualize the spatial relationship between brain structures before he performs a craniotomy and during the surgery he can see what's under the next layer before he cuts through. Given a video image of the patient and a three dimensional model of the patient's brain the problem enhanced reality visualization faces is to render the model from the correct viewpoint and overlay it on the original image. The relationship between the coordinate frames of the patient, the patient's internal anatomy scans and the image plane of the camera observing the patient must be established. This problem is closely related to the camera calibration problem. This report presents a new approach to finding this relationship and develops a system for performing enhanced reality visualization in a surgical environment. Immediately prior to surgery a few circular fiducials are placed near the surgical site. An initial registration of video and internal data is performed using a laser scanner. Following this, our method is fully automatic, runs in nearly real-time, is accurate to within a pixel, allows both patient and camera motion, automatically corrects for changes to the internal camera parameters (focal length, focus, aperture, etc.) and requires only a single image.
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Segmentation of medical imagery is a challenging problem due to the complexity of the images, as well as to the absence of models of the anatomy that fully capture the possible deformations in each structure. Brain tissue is a particularly complex structure, and its segmentation is an important step for studies in temporal change detection of morphology, as well as for 3D visualization in surgical planning. In this paper, we present a method for segmentation of brain tissue from magnetic resonance images that is a combination of three existing techniques from the Computer Vision literature: EM segmentation, binary morphology, and active contour models. Each of these techniques has been customized for the problem of brain tissue segmentation in a way that the resultant method is more robust than its components. Finally, we present the results of a parallel implementation of this method on IBM's supercomputer Power Visualization System for a database of 20 brain scans each with 256x256x124 voxels and validate those against segmentations generated by neuroanatomy experts.
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We develop efficient techniques for the non-rigid registration of medical images by using representations that adapt to the anatomy found in such images. Images of anatomical structures typically have uniform intensity interiors and smooth boundaries. We create methods to represent such regions compactly using tetrahedra. Unlike voxel-based representations, tetrahedra can accurately describe the expected smooth surfaces of medical objects. Furthermore, the interior of such objects can be represented using a small number of tetrahedra. Rather than describing a medical object using tens of thousands of voxels, our representations generally contain only a few thousand elements. Tetrahedra facilitate the creation of efficient non-rigid registration algorithms based on finite element methods (FEM). We create a fast, FEM-based method to non-rigidly register segmented anatomical structures from two subjects. Using our compact tetrahedral representations, this method generally requires less than one minute of processing time on a desktop PC. We also create a novel method for the non-rigid registration of gray scale images. To facilitate a fast method, we create a tetrahedral representation of a displacement field that automatically adapts to both the anatomy in an image and to the displacement field. The resulting algorithm has a computational cost that is dominated by the number of nodes in the mesh (about 10,000), rather than the number of voxels in an image (nearly 10,000,000). For many non-rigid registration problems, we can find a transformation from one image to another in five minutes. This speed is important as it allows use of the algorithm during surgery. We apply our algorithms to find correlations between the shape of anatomical structures and the presence of schizophrenia. We show that a study based on our representations outperforms studies based on other representations. We also use the results of our non-rigid registration algorithm as the basis of a segmentation algorithm. That algorithm also outperforms other methods in our tests, producing smoother segmentations and more accurately reproducing manual segmentations.
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Es el reimplante valvular mejor que el Bentall Biolgico Modificado para tratar aneurismas de la raz asociados a insuficiencia? Obando CE; Gutirrez HF; Santamara G, Bresciani R; Camacho J; Sandoval N; Umaa J. Departamento de Ciruga Cardiovascular, Fundacin Cardio Infantil, Bogot, Colombia. Objetivo: comparar resultados funcionales, morbilidad y sobrevida a corto y mediano plazo, tras la realizacin de Bentall modificado con prtesis Freestyle vs reimplante valvular de Tirone David, en insuficiencia aortica secundaria a aneurisma de la raz. Diseo: revisin de registros institucionales de 88 pacientes tratados entre enero de 2003 y agosto de 2009 con insuficiencia aortica secundaria a aneurisma de la raz sin dao valvular, distribuidos en dos cohortes: Grupo 1 (Bentall modificado) y Grupo 2 (reimplante valvular). Se evaluaron complicaciones perioperatorias, transfusiones, estancias hospitalarias y en el seguimiento a mediano plazo insuficiencia valvular, clase funcional, funcin ventricular y sobrevida. Solidez de los resultados verificada mediante anlisis de propensidad con balanceo de grupos. Resultados: Grupo (1) 51(57.9%) pacientes y grupo (2) 37(42.1%). Aunque el grupo 2 es mas joven, patrones similares de coomorbilidad, anatoma de la raz, funcin y dimetros ventriculares hacen comparables los dos grupos. Seguimiento de 3.3 aos (IQR 2.0-4.4). Mortalidad temprana 2(3.8%) vs 0 p =0.2 y tarda de 2(4.1%) vs 0 p=0.33. El anlisis estratificado de covariables en bloques de distribucin tampoco identifica diferencias en mortalidad. El anlisis de sobrevida de mortalidad y sobrevida libre de eventos identifica desenlaces similares entre los grupos (Log-Rank chi2=0.9, p=0.3); incluyendo Insuficiencia aortica = II temprana (3.8% vs 0, p=0.2) y tarda (3.8%vs 0, p=0.1), transfusiones perioperatorias, reintervenciones por sangrado (2.3% vs 3.4%, p=0.4), arritmias (25.5% vs 13.5%, p=0.2) y disfuncin neurolgica (5.7% vs 2.9%, p=0.9). Finalmente la hospitalizacin total (6.5 {1-35} vs 4{3-16} p=0.001) y estancia en Cuidado intensivo (2.5 {1-21} vs 1{1-16} p=0.001) es superior en el grupo1. Conclusiones: el tratamiento de los aneurismas de la raz aortica asociados a insuficiencia valvular sin dao estructural, mediante reimplante valvular o Bentall biolgico modificado ofrece resultados similares a corto y mediano plazo. La preservacin valvular se asocia a estancias mas cortas, pero no hay diferencia en complicaciones postoperatorias, estatus funcional, insuficiencia valvular, funcin ventricular, mortalidad y sobrevida libre de eventos adversos.
