Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 3 de 3
Filtrar
1.
Can J Neurol Sci ; 43(3): 398-401, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26787132

RESUMEN

BACKGROUND: The head impulse test (HIT) is an evidenced based clinical tool to differentiate between peripheral and central causes of vertigo. Our objective was to determine the rate of utilization of the HIT in the emergency room (ER). METHODS: A retrospective chart review of patients presenting to the ER over one year who received a final diagnosis of dizziness or vertigo. Details of clinical examinations, investigations, and diagnosis were recorded. Patients were grouped into episodic, acute constant, and chronic vertigo groups. RESULTS: HIT was performed in only 31 of 642 (5%) patients with vertigo. In the acute constant group it was negative in 6 of 6 patients ultimately diagnosed with stroke and positive in 6 of 13 cases of peripheral vertigo. DISCUSSION: Despite good published evidence regarding its use the HIT is under-utilized in the ER. Physicians need to be aware of the HIT and newer video HITs and make use of them in practice.


Asunto(s)
Servicio de Urgencia en Hospital/estadística & datos numéricos , Prueba de Impulso Cefálico/métodos , Prueba de Impulso Cefálico/estadística & datos numéricos , Accidente Cerebrovascular/diagnóstico , Vértigo/diagnóstico , Anciano , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tomógrafos Computarizados por Rayos X
2.
Mol Phylogenet Evol ; 52(3): 879-86, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19394432

RESUMEN

Most of the species of the family Rubiaceae with flowers arranged in head inflorescences are currently classified in three distantly related tribes, Naucleeae (subfamily Cinchonoideae) and Morindeae and Schradereae (subfamily Rubioideae). Within Morindeae the type genus Morinda is traditionally and currently circumscribed based on its head inflorescences and syncarpous fruits (syncarps). These characters are also present in some members of its allied genera, raising doubts about the monophyly of Morinda. We perform Bayesian phylogenetic analyses using combined nrETS/nrITS/trnT-F data for 67 Morindeae taxa and five outgroups from the closely related tribes Mitchelleae and Gaertnereae to rigorously test the monophyly of Morinda as currently delimited and assess the phylogenetic value of head inflorescences and syncarps in Morinda and Morindeae and to evaluate generic relationships and limits in Morindeae. Our analyses demonstrate that head inflorescences and syncarps in Morinda and Morindeae are evolutionarily labile. Morinda is highly paraphyletic, unless the genera Coelospermum, Gynochthodes, Pogonolobus, and Sarcopygme are also included. Morindeae comprises four well-supported and morphologically distinct major lineages: Appunia clade, Morinda clade (including Sarcopygme and the lectotype M. royoc), Coelospermum clade (containing Pogonolobus and Morinda reticulata), and Gynochthodes-Morinda clade. Four possible alternatives for revising generic boundaries are presented to establish monophyletic units. We favor the recognition of the four major lineages of Morindeae as separate genera, because this classification reflects the occurrence of a considerable morphological diversity in the tribe and the phylogenetic and taxonomic distinctness of its newly delimited genera.


Asunto(s)
Evolución Molecular , Morinda/genética , Filogenia , Teorema de Bayes , Núcleo Celular/genética , ADN de Cloroplastos/genética , ADN de Plantas/genética , ADN Ribosómico/genética , Flores/genética , Genoma de Planta , Morinda/clasificación , Alineación de Secuencia , Análisis de Secuencia de ADN
3.
PLoS One ; 7(7): e40851, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22815842

RESUMEN

During angiosperm evolution, innovations in vegetative and reproductive organs have resulted in tremendous morphological diversity, which has played a crucial role in the ecological success of flowering plants. Morindeae (Rubiaceae) display considerable diversity in growth form, inflorescence architecture, flower size, and fruit type. Lianescent habit, head inflorescence, small flower, and multiple fruit are the predominant states, but arborescent habit, non-headed inflorescence, large flower, and simple fruit states occur in various genera. This makes Morindeae an ideal model for exploring the evolutionary appearances and transitions between the states of these characters. We reconstructed ancestral states for these four traits using a bayesian approach and combined nuclear/chloroplast data for 61 Morindeae species. The aim was to test three hypotheses: 1) self-supporting habit is generally ancestral in clades comprising both lianescent and arborescent species; 2) changes from lianescent to arborescent habit are uncommon due to "a high degree of specialization and developmental burden"; 3) head inflorescences and multiple fruits in Morindeae evolved from non-headed inflorescences and simple fruits, respectively. Lianescent habit, head inflorescence, large flower, and multiple fruit are inferred for Morindeae, making arborescent habit, non-headed inflorescence, small flower, and simple fruit derived within the tribe. The rate of change from lianescent to arborescent habit is much higher than the reverse change. Therefore, evolutionary changes between lianescent and arborescent forms can be reversible, and their frequency and trends vary between groups. Moreover, these changes are partly attributed to a scarcity of host trees for climbing plants in more open habitats. Changes from large to small flowers might have been driven by shifts to pollinators with progressively shorter proboscis, which are associated with shifts in breeding systems towards dioecy. A single origin of dioecy from hermaphroditism is supported. Finally, we report evolutionary changes from headed to non-headed inflorescences and multiple to simple fruits.


Asunto(s)
Evolución Biológica , Fenómenos Ecológicos y Ambientales , Frutas/anatomía & histología , Inflorescencia/anatomía & histología , Inflorescencia/crecimiento & desarrollo , Rubiaceae/anatomía & histología , Rubiaceae/crecimiento & desarrollo , Teorema de Bayes , Tamaño de los Órganos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA