RESUMEN
The P3(00) event-related brain potential (ERP) was elicited with an auditory tone-discrimination paradigm in 25 patients diagnosed with chronic fatigue syndrome (CFS) and 25 matched normal control subjects. Target stimulus probability was varied systematically (0.20, 0.50, 0.80) in different task conditions. No differences between the CFS and control subjects were found for either P3 amplitude or latency. No group effects were observed for the N1, P2, and N2 components. Despite the attentional and immediate memory deficits reported in CFS, the P3 ERP from auditory stimuli does not reliably discriminate CFS from matched control subjects.
Asunto(s)
Nivel de Alerta/fisiología , Atención/fisiología , Potenciales Evocados Auditivos/fisiología , Síndrome de Fatiga Crónica/fisiopatología , Discriminación de la Altura Tonal/fisiología , Estimulación Acústica , Adulto , Corteza Cerebral/fisiopatología , Síndrome de Fatiga Crónica/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tiempo de Reacción/fisiología , Valores de ReferenciaRESUMEN
Here, we present the experimental data, leading to determination of the primary structure, the linkage of the carbohydrates and the arrangements of the disulfide bonds of the human free secretory component. Methods of protein chemistry were used. The protein can be divided into five homology regions and is a member of the immunoglobulin superfamily.
Asunto(s)
Calostro/química , Componente Secretorio/química , Secuencia de Aminoácidos , Carbohidratos/química , Cromatografía Líquida de Alta Presión , Disulfuros/química , Humanos , Inmunoglobulinas/clasificación , Datos de Secuencia Molecular , Homología de Secuencia de Ácido NucleicoRESUMEN
This study was undertaken to measure the degree of high-frequency sensorineural hearing loss following mastoid surgery. Twenty-five patients undergoing mastoidectomy procedures were tested preoperatively, less than 2 days postoperatively, and at 30 days postoperatively using the Tonndorf Audimax 500 high-frequency audiometer. Electrostimulation thresholds in 1-kHz intervals, from 1 to 20 kHz, were measured, and the highest detectable frequency was determined to within 0.1 kHz. Surgical drilling time was recorded. Average drilling time was 51 minutes. A significant temporary threshold shift was observed, measurable at multiple frequencies, less than 48 hours after mastoidectomy. There was no clinically significant change in electrostimulation thresholds (measured in 1-kHz increments, from 1 to 16 kHz) preoperatively to 30 days postoperatively. A statistically significant average loss of 0.89 kHz in the highest frequency producing a measurable response was noted (p less than 0.05). Determinations of the highest measurable frequency may be the most sensitive measure of surgically-induced, high-frequency sensorineural hearing changes.