{"id":41758,"date":"1999-01-01T00:00:00","date_gmt":"1999-01-01T00:00:00","guid":{"rendered":"https:\/\/www.deberes.net\/tesis\/sin-categoria\/fundamentos-del-contraste-en-imagenes-de-resonancia-magnetica\/"},"modified":"1999-01-01T00:00:00","modified_gmt":"1999-01-01T00:00:00","slug":"fundamentos-del-contraste-en-imagenes-de-resonancia-magnetica","status":"publish","type":"post","link":"https:\/\/www.deberes.net\/tesis\/quimica\/fundamentos-del-contraste-en-imagenes-de-resonancia-magnetica\/","title":{"rendered":"Fundamentos del contraste en imagenes de resonancia magnetica."},"content":{"rendered":"<h2>Tesis doctoral de <strong> Jose Alvarez Perez <\/strong><\/h2>\n<p>Se han estudiado cuantitativamente los determinantes fisiol\u00f3gicos y fisicoqu\u00edmicos del contraste intr\u00ednseco en imagen por resonancia magn\u00e9tica (rm), poniendo \u00e9nfasis en los efectos del contenido tisular de agua y en los determinantes de su visibilidad a la ram. Se determin\u00f3 el contenido tisular de agua en ratas de diversas edades y se estudi\u00f3 cuantitativamente la concentraci\u00f3n de agua invisible a la rm en soluciones modelo de electrolitos, prote\u00ednas, fosfol\u00edpidos, polisac\u00e1ridos y tambi\u00e9n en suspensiones celulares.  el contenido corporal de agua determinado en ratas disminuye con la edad siguiendo una cin\u00e9tica biexponencial de manera que la hidrataci\u00f3n promedio de los tejidos desciende aproximadamente un 20% al final de la ontogenia.  la disoluci\u00f3n de cualquiera de los solutos estudiados en agua, resulta en la invisibilizaci\u00f3n a la rm de una parte del agua de la soluci\u00f3n. Se demuestra que esta invisibilizaci\u00f3n ocurre como consecuencia de una alteraci\u00f3n en el balance de interacciones entre las mol\u00e9culas de agua al formarsa la soluci\u00f3n. Esta alteraci\u00f3n sigue un modelo de sorci\u00f3n del tipo brunauer-emmet-teller y se deriva de la aparici\u00f3n de nuevas interacciones intermoleculares soluto-solvente y solvente-solvente, estando relacionada con la solubilidad y el grado de solvatoci\u00f3n del soluto.  se ha estudiado la termodin\u00e1mica del proceso de invisibilizaci\u00f3n. La formaci\u00f3n del complejo activado agua invisible-soluto es independiente de la naturaleza qu\u00edmica del soluto, presentando una energ\u00eda de activaci\u00f3n de 4 kcal.Mol-1 y una entrop\u00eda de activaci\u00f3n de -77 kcal.Mol-1.K-1. Estos resultados indican que la formaci\u00f3n del complejo activado requiere el aporte de energ\u00eda del entorno e involucra una estructuraci\u00f3n de las mol\u00e9culas de agua en la concha de solvataci\u00f3n del soluto. Sin embargo, la descomposici\u00f3n de este complejo activado para originar el agua invisible a la rm presenta propiedades caracter<\/p>\n<p>&nbsp;<\/p>\n<h3>Datos acad\u00e9micos de la tesis doctoral \u00ab<strong>Fundamentos del contraste en imagenes de resonancia magnetica.<\/strong>\u00ab<\/h3>\n<ul>\n<li><strong>T\u00edtulo de la tesis:<\/strong>\u00a0 Fundamentos del contraste en imagenes de resonancia magnetica. <\/li>\n<li><strong>Autor:<\/strong>\u00a0 Jose Alvarez Perez <\/li>\n<li><strong>Universidad:<\/strong>\u00a0 Aut\u00f3noma de Madrid<\/li>\n<li><strong>Fecha de lectura de la tesis:<\/strong>\u00a0 01\/01\/1999<\/li>\n<\/ul>\n<p>&nbsp;<\/p>\n<h3>Direcci\u00f3n y tribunal<\/h3>\n<ul>\n<li><strong>Director de la tesis<\/strong>\n<ul>\n<li>esteller Cerd\u00e1n Garc\u00eda<\/li>\n<\/ul>\n<\/li>\n<li><strong>Tribunal<\/strong>\n<ul>\n<li>Presidente del tribunal: Juan  jos\u00e9 Arag\u00f3n reyes <\/li>\n<li> Garcia perez Ana i. (vocal)<\/li>\n<li>paloma Ballesteros Garc\u00eda (vocal)<\/li>\n<li> Garc\u00eda segura Juan  Manuel (vocal)<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Tesis doctoral de Jose Alvarez Perez Se han estudiado cuantitativamente los determinantes fisiol\u00f3gicos y fisicoqu\u00edmicos del contraste intr\u00ednseco en imagen [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""}},"footnotes":""},"categories":[21662,199,1008,17,18,28867],"tags":[14520,105540,5831,105539,14521,2508],"class_list":["post-41758","post","type-post","status-publish","format-standard","hentry","category-espectroscopia-de-resonancia-magnetica","category-fisica","category-fisica-del-estado-solido","category-quimica","category-quimica-analitica","category-resonancia-magnetica","tag-esteller-cerdan-garcia","tag-garcia-perez-ana-i","tag-garcia-segura-juan-manuel","tag-jose-alvarez-perez","tag-juan-jose-aragon-reyes","tag-paloma-ballesteros-garcia"],"_links":{"self":[{"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/posts\/41758","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/comments?post=41758"}],"version-history":[{"count":0,"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/posts\/41758\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/media?parent=41758"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/categories?post=41758"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/tags?post=41758"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}