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Endoscopía/métodos , Interfaz Usuario-Computador , Anciano , Simulación por Computador , Presentación de Datos , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Tecnología Radiológica , Tomografía Computarizada por Rayos XRESUMEN
BACKGROUND AND PURPOSE: Transcranial Doppler ultrasonography (TCD) is the standard technique for monitoring emboli in the cerebral circulation. Embolic signals have been detected with the use of this technique in most patients undergoing coronary artery bypass surgery. We previously reported that the majority of emboli are detected after release of aortic cross-clamps and partial occlusion clamps. In this study we compare the intraoperative use of TCD with transesophageal echocardiography (TEE) to monitor cerebral emboli. METHODS: We simultaneously monitored 20 patients undergoing coronary bypass surgery with TCD and TEE. All patients also underwent routine TEE examination of the aorta. RESULTS: Embolic signals were detected in all patients by both techniques. Mean total number of emboli was 535 +/- 109 by TEE compared with 133 +/- 28 by TCD. We found correlation between numbers of emboli detected by the two techniques at clamp placement and release (r = .65, P = .002). Clamp placement and release accounted for 84% of all emboli by TEE and 83% by TCD. By TEE, large, highly echogenic particles were detected after clamp release compared with small, barely echodense particles at the onset of bypass. No such distinction was apparent by TCD. We found correlation between severity of aortic atheroma and both TEE- (P = .003) and TCD-detected (P = .009) emboli. CONCLUSIONS: TEE and TCD can both be used to continuously monitor emboli during coronary artery bypass surgery. However, TEE is invasive and justified only if it is being performed for intraoperative assessment of aortic atheromatosis or cardiac function.
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Puente de Arteria Coronaria , Ecocardiografía Transesofágica , Embolia y Trombosis Intracraneal/diagnóstico por imagen , Monitoreo Intraoperatorio , Ultrasonografía Doppler Transcraneal , Anciano , Análisis de Varianza , Aorta/diagnóstico por imagen , Aorta/cirugía , Aorta Torácica/diagnóstico por imagen , Aorta Torácica/cirugía , Enfermedades de la Aorta/diagnóstico por imagen , Enfermedades de la Aorta/cirugía , Arteriosclerosis/diagnóstico por imagen , Arteriosclerosis/cirugía , Puente Cardiopulmonar , Procedimientos Quirúrgicos Electivos , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Análisis Multivariante , Ultrasonografía Intervencional , Grabación de Cinta de VideoRESUMEN
The oxidation of cinnamyl alcohol to cinnamaldehyde by horse liver alcohol dehydrogenase (LADH) was carried out in nearly anhydrous organic solvents and in solvents containing from 0.1 to 10% added water. In nearly anhydrous solvents containing less than 0.02% water, the oxidation rate increased as the water solubility in the solvent decreased, but the reaction did not require active LADH. Moreover, the highest activity in nearly anhydrous heptane was obtained by lyophilizing the enzyme from a solution of pH 2.0, even though LADH exhibits virtually no enzymatic activity in water at this pH. The catalytic activity of LADH was restored and increased dramatically as small amounts of water were added to each solvent. In conjunction with the activity measurements, electron paramagnetic resonance (EPR) spectroscopy and two active-site directed spin labels were used to examine solvent-dependent structural features of LADH. The EPR spectra indicated that LADH became more rigid as the dielectric constant of the solvent decreased. The degree of rigidity also depended on the pH from which the enzyme was lyophilized, indicating that the ionization state of the enzyme can have an important influence on its dynamics in organic solvents. Finally, adding 1% water to organic solvents had no apparent effect on the enzyme's conformation or flexibility near the spin label, even though enzyme activity was an order of magnitude higher when 1% water was present.
RESUMEN
PIP: Regional changes in residential and daytime population density for the San Diego area of California are presented for 1986 and projected for 2010. The focus is on the impact of commuting on densities in suburban communities and metropolitan areas.^ieng
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Demografía , Geografía , Densidad de Población , Transportes , Américas , Conducta , California , Países Desarrollados , América del Norte , Población , Investigación , Estados UnidosRESUMEN
In order to check the concurrent validity of the Differential Personality Inventory (DPI), the authors gave the test to 60 psychiatric patients (25 men, 35 women), who also were observed and rated on Lorr and Vestre's Psychotic Inpatient Profile. Patients also took Whitaker's Index of Schizophrenic Thinking (WIST), a test that measures thought disorder. The patients received higher scores on appropriate scales of the DPI than did a normative group (N = 370) of university students. We predicted that six of the DPI scales would correlate with relevant criterion measures (Lorr-Vestre scales and WIST); in five of six instances such correlations were statistically significant. We conclude that the DPI discriminates psychotics from normals and that among psychotics it has a moderate power to discriminate among types of psychotic behavior.