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L'IRM cardiaque en séquence SSFP GE est devenue au cours des dernières dizaines d'années la technique de référence pour l'évaluation de la fonction cardiaque. L'excellente résolution temporelle, le contraste sang-myocarde spontané ainsi que le caractère non-invasif et non irradiant de la technique ne sont que quelques arguments en faveur de la technique. De plus, l'évaluation de la fonction cardiaque fait de plus en plus partie intégrante de l'examen cardiovasculaire de routine en clinique. Seulement quelques études se sont consacrées à la détermination des valeurs de volumes, de masses et fonctionnelles ventriculaire chez les enfants, le plus souvent à partir de petites cohortes, et utilisant différentes techniques d'acquisition. Ce manque de valeurs de référence représente une limitation à l'utilisation de l'IRM en cardiologie pédiatrique. Le but de notre étude est de déterminer des valeurs normatives de volume, de masse et de fonction bi-ventriculaire en IRM cardiaque SSFP à partir d'une cohorte d'enfants entre 0 et 18 ans. Matériel et méthodes : Nous avons étudié de manière rétrospective les examens en IRM cardiaque court-axe (en IRM SSFP 1.5T) de 158 enfants âgés de 18 jours à 18 ans et 215 jours. Une échocardiographie normale et l'absence d'antécédents cardiovasculaires faisaient partie des critères d'inclusion à notre cohorte. Nous avons déterminé les volumes télé systoliques et télé diastoliques et la masse ventriculaire gauche et droite pour chaque enfant, à partir d'une technique utilisée fréquemment en clinique et validée par la littérature. Pour chaque paramètre, nous avons déterminé les valeurs moyennes, selon le sexe et par groupe d'âge (0-6, 7-12, 13-18 ans).Résultats: Nous avons déterminé les valeurs moyennes pour le volume en télésystole, en télédiastole, la fraction d'éjection et la mise pour les garçons et les filles et pour chaque groupe d'âge, ainsi que les valeurs indexées sur la surface corporelle (BSA), la taille et le poids. Nous avons trouvé une augmentation avec l'âge pour les volumes bi-ventriculaires indexés sur le BSA et la taille, ainsi qu'une augmentation de la masse bi-ventriculaire indexée sur le BSA et sur le poids. La fraction d'éjection biventriculaire est stable dans les différents groupes d'âge. La fraction d'éjection n'est pas différente entre le groupe des garçons et le groupe des filles. La masse ventriculaire gauche est plus; élevée de manière significative dans notre groupe de garçons. Les volumes indexés sur le BSA et sur le poids sont également plus élevés chez les garçons.Conclusion : Nous avons déterminé des valeurs fonctionnelles, volumiques et de masse bi-ventriculaires dans une population pédiatrique en bonne santé entre 0 et 18 ans, incluant des très petits bébés, à IRM 1.5T SSFP. Nos valeurs sont comparables avec celles déterminées dans les précédentes études, plus particulièrement pour le ventricule gauche. Nous données pourront être utilisées à l'avenir pour réaliser des courbes de percentile pour les valeurs indexées. SSFP GE sequence in cardiac magnetic resonance imaging has emerged in the past decades as the gold standard technique to evaluate cardiac function. The excellent temporal resolution, along with a very good blood-myocardiaum contrast, as well as the non-invasive character of the technique is only some of the numerous advantages offered by MRI. ln addition, the assessment of cardiac function is becoming an integrant part of the routine cardiac clinical examination. Only a few studies did measure the ventricular function, volumes and mass in small groups of healthy children population, and using different acquisition techniques. This lack of normative data is a limiting factor in the optimal use of pediatric cardiac MRI. The aim of our study is to establish normative data for biventricular volumes, mass and function in SSFP MRI from a healthy pediatric population between 0 and 18 years.Material and methods : We retrospectively studied short axis cardiac MRI (performed on 1.ST SSFP MRI system) of 158 children aged 18 days to 18 years and 215 days, all of them having a normal echocardiography and no cardiovascular history. We calculated end-systolic and end diastolic volumes and mass for the right and left ventricle for each child, according to a method frequently used in clinical practice. For each parameter, we determined the mean value, according to the child sex and for each age group (0-6, 7-12 and 13-18 years old).Results : We did determine mean values for biventricular end-systolic, end-diastolic volumes, ejection fraction and mass for the boys and the girls and each age group, as well as the indexed values for body surface area (BSA), size and weight. We did find an increase with age for both BSA and size indexed left and right volumes, and BSA and weight indexed biventricular mass. Biventricular ejection fraction is stable throughout the ages groups. Biventricular ejection fraction is not different in the boys and girls groups. Left ventricular mass is significantly higher in the boys group. BSA and weight indexed biventricular volumes are higher in our boys population as well. Conclusion: We did determine normative biventricular volumic, functional and mass values for a healthy pediatric population, including very young babies in 1.5 T SSFP MRI. Our values were comparable with the ones determined in former studies, especially for left ventricle. Our data could be used in the future to determine percentile curves for indexed values.
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Solving Problems with NMR Spectroscopy presents the basic principles and applications of NMR spectroscopy with only as much math as is necessary. It shows how to solve chemical structures with NMR by giving clear examples and solutions. This text will enable organic chemistry students to choose the most appropriate NMR techniques to solve specific structures. The problems to work and the discussion of their solutions and interpretations will help readers becomeproficient in the application of important, modern 1D and 2D NMR techniques to structural studies.Key Features* Pres
Nuclear magnetic resonance spectroscopy. --- Nuclear spectroscopy. --- Spectroscopy, Nuclear --- Nuclear reactions --- Radiation --- Spectrum analysis --- NMR spectroscopy --- Spectroscopy, NMR --- Spectroscopy, Nuclear magnetic resonance --- Nuclear spectroscopy --- Knight shift --- Nmr spectroscopy
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In the past few decades, magnetic resonance imaging (MRI) has become an indispensable tool in modern medicine, with MRI systems now available at every major hospital in the developed world. But for all its utility and prevalence, it is much less commonly understood and less readily explained than other common medical imaging techniques. Unlike optical, ultrasonic, x-ray (including CT), and nuclear medicine-based imaging, MRI does not rely primarily on simple transmission and/or reflection of energy, and the highest achievable resolution in MRI is orders of magnitude smaller that the smallest wavelength involved. In this book, MRI will be explained with emphasis on the magnetic fields required, their generation, their concomitant electric fields, the various interactions of all these fields with the subject being imaged, and the implications of these interactions to image quality and patient safety. Classical electromagnetics will be used to describe aspects from the fundamental phenomenon of nuclear precession through signal detection and MRI safety. Simple explanations and Illustrations combined with pertinent equations are designed to help the reader rapidly gain a fundamental understanding and an appreciation of this technology as it is used today, as well as ongoing advances that will increase its value in the future. Numerous references are included to facilitate further study with an emphasis on areas most directly related to electromagnetics.
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This book presents the underlying physics and mathematics in a way that isboth accessible and sufficiently complete to allow a real understanding ofmodern multi-dimensional experiments, thereby giving readers the toolsthey need to move to more advanced textbooks and articles.
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High-Resolution NMR Techniques in Organic Chemistry, Third Edition describes the most important NMR spectroscopy techniques for the structure elucidation of organic molecules and the investigation of their behaviour in solution. Appropriate for advanced undergraduate and graduate students, research chemists and NMR facility managers, this thorough revision covers practical aspects of NMR techniques and instrumentation, data collection, and spectrum interpretation. It describes all major classes of one- and two-dimensional NMR experiments including homonuclear and heteronuclear correlations, the nuclear Overhauser effect, diffusion measurements, and techniques for studying protein–ligand interactions. A trusted authority on this critical expertise, High-Resolution NMR Techniques in Organic Chemistry, Third Edition is an essential resource for every chemist and NMR spectroscopist.
Nuclear magnetic resonance spectroscopy. --- Organic compounds --- Chemistry, Organic. --- Organic chemistry --- Chemistry --- NMR spectroscopy --- Spectroscopy, NMR --- Spectroscopy, Nuclear magnetic resonance --- Nuclear spectroscopy --- Knight shift --- Analysis. --- Espectroscopía UV-visible IR y RMN (71101104) --- Ampliación de Química Orgánica (50904220) |x Bibliografía recomendada --- Bibliografía recomendada --- Nuclear magnetic resonance spectroscopy --- Chemistry, Organic --- Analysis
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NMR of Paramagnetic Molecules: Applications to Metallobiomolecules and Models, Second Edition is a self-contained, comprehensive reference for chemists, physicists, and life scientists whose research involves analyzing paramagnetic compounds. Since the previous edition of this book was published, there have been many advancements in the field of paramagnetic NMR spectroscopy. This completely updated and expanded edition contains the latest fundamental theory and methods for mastery of this analytical technique. Users will learn how to interpret the NMR spectra of paramagnetic molecules, improve experimental techniques, and strengthen their understanding of the underlying theory and applications.
Nuclear magnetic resonance. --- Paramagnetism. --- Biochemistry --- Methodology. --- Biological chemistry --- Chemical composition of organisms --- Organisms --- Physiological chemistry --- Biology --- Chemistry --- Medical sciences --- Magnetism --- Nuclear magnetic resonance --- Nuclear moments --- Magnetic resonance, Nuclear --- NMR (Nuclear magnetic resonance) --- Nuclear spin resonance --- Resonance, Nuclear spin --- Magnetic resonance --- Nuclear spin --- Nuclear quadrupole resonance --- Composition
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