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1.
Artículo en Inglés | MEDLINE | ID: mdl-23647107

RESUMEN

This article provides a review of the routine methods currently utilized for total naphthenic acid analyses. There is a growing need to develop chemical methods that can selectively distinguish compounds found within industrially derived oil sands process affected waters (OSPW) from those derived from the natural weathering of oil sands deposits. Attention is thus given to the characterization of other OSPW components such as oil sands polar organic compounds, PAHs, and heavy metals along with characterization of chemical additives such as polyacrylamide polymers and trace levels of boron species. Environmental samples discussed cover the following matrices: OSPW containments, on-lease interceptor well systems, on- and off-lease groundwater, and river and lake surface waters. There are diverse ranges of methods available for analyses of total naphthenic acids. However, there is a need for inter-laboratory studies to compare their accuracy and precision for routine analyses. Recent advances in high- and medium-resolution mass spectrometry, concomitant with comprehensive mass spectrometry techniques following multi-dimensional chromatography or ion-mobility separations, have allowed for the speciation of monocarboxylic naphthenic acids along with a wide range of other species including humics. The distributions of oil sands polar organic compounds, particularly the sulphur containing species (i.e., OxS and OxS2) may allow for distinguishing sources of OSPW. The ratios of oxygen- (i.e., Ox) and nitrogen-containing species (i.e., NOx, and N2Ox) are useful for differentiating organic components derived from OSPW from natural components found within receiving waters. Synchronous fluorescence spectroscopy also provides a powerful screening technique capable of quickly detecting the presence of aromatic organic acids contained within oil sands naphthenic acid mixtures. Synchronous fluorescence spectroscopy provides diagnostic profiles for OSPW and potentially impacted groundwater that can be compared against reference groundwater and surface water samples. Novel applications of X-ray absorption near edge spectroscopy (XANES) are emerging for speciation of sulphur-containing species (both organic and inorganic components) as well as industrially derived boron-containing species. There is strong potential for an environmental forensics application of XANES for chemical fingerprinting of weathered sulphur-containing species and industrial additives in OSPW.


Asunto(s)
Ácidos Carboxílicos/análisis , Monitoreo del Ambiente/métodos , Contaminantes Químicos del Agua/análisis , Espectrometría de Masas , Hidrocarburos Policíclicos Aromáticos/análisis
2.
Arch Neurol ; 46(9): 1024-7, 1989 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2775008

RESUMEN

This article describes a patient who experienced the rapid onset of an irreversible behavioral change while vacationing in La Paz, Bolivia (altitude, 4070 m). The only lesions demonstrated on a magnetic resonance imaging scan were bilateral hemorrhages in the globus pallidus. The behavior change was characterized by apathy and lack of motivation, features commonly associated with bilateral frontal lobe disease. This case is a further demonstration of how subcortical lesions can produce behavioral syndromes that are clinically indistinguishable from classic cortical syndromes. It is cases such as this that show how a strict localizationist concept of behavioral function is too restrictive and how it is necessary to consider a wide network of neuronal interconnections when explaining the mechanism of a dissolution of complex higher functions.


Asunto(s)
Conducta , Hemorragia Cerebral/complicaciones , Lóbulo Frontal , Globo Pálido , Encefalopatías/etiología , Encefalopatías/psicología , Humanos , Masculino , Persona de Mediana Edad , Motivación , Aislamiento Social , Síndrome
3.
J Clin Psychiatry ; 40(9): 386-8, 1979 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-479115

RESUMEN

Bedside mental status testing in low IQ, poorly educated patients is often difficult. These patients, who comprise a significant proportion of the population served by major inner city public hospitals, have a limited ability to perform adequately on many higher cortical function tests. Because of this, it is often difficult to accurately differentiate between an organic brain syndrome and the effect of depressed intelligence in these patients. Copying line drawings and other constructional tasks are a very important element in a complete mental status examination, as they are frequently failed by patients with organic brain disease. The applicability of drawing tasks in the low IQ patient is an important issue; this study demonstrates that selected drawings can be effectively utilized to identify brain dysfunction in this low IQ population.


Asunto(s)
Percepción de Forma , Discapacidad Intelectual/psicología , Inteligencia , Daño Encefálico Crónico/psicología , Percepción de Profundidad , Femenino , Humanos , Masculino , Reconocimiento Visual de Modelos , Pruebas Psicológicas
4.
Cortex ; 14(1): 12-21, 1978 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16295105

RESUMEN

Digit span forward and backward was investigated in well-matched samples of patients with discrete quadrant brain lesions. The incidence of significantly impaired digit repetition performance and the incidence of large forward and backward digit span discrepancies were also studied. Correlational data of digit span performance and various intellectual, memory, and constructional measures was examined. Approximately 60% of all brain-damaged patients showed an impairment of digit span forward, while only 5% showed a similar impairment on the digit span backward task. These data indicate that digit span forward is a more sensitive measure of brain dysfunction from focal brain lesions. No difference was found in the performance of patients with right or left hemisphere lesions; however, the low incidence of aphasia (8%) in this sample may account in part for the relatively adequate performance by the left hemisphere patients. Although the current data regarding visual constructive deficits and impaired ability to repeat digits backward is inconclusive, there did not appear to be a strong relationship between these two functions for these patients. Digit repetition performance does appear to be related to both general intellectual ability and to performance on the Wechsler Memory Scale.


Asunto(s)
Lesiones Encefálicas/psicología , Memoria a Corto Plazo/fisiología , Adolescente , Adulto , Femenino , Humanos , Inteligencia , Masculino , Memoria/fisiología , Pruebas Neuropsicológicas , Desempeño Psicomotor/fisiología , Percepción Visual/fisiología
5.
Cortex ; 12(3): 212-20, 1976 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1000989

RESUMEN

Sixty patients with missile wounds confined to one of the four quadrants of the brain were investigated. All patients had neurosurgical verification of the limits of their lesions. The incidence and severity of constructional apraxia was studied using the WAIS Block Design and Object Assembly subtests, and the Bender Gestalt Test. A uniformly significant caudality effect was obtained with more posteriorly localized lesions resulting in more severe constructional apraxia. A significant laterality effect was obtained on two of three criterion measures with uniformly inferior performance by patients with right hemisphere lesions. The magnitude of the laterality effect, however, was less than that of the caudality effect for all criterion variables. The degree of severity of constructional apraxia in patients with right posterior lesions was uniformly greater than that of patients with other quadrant loci. The incidence of constructional apraxia in the four quadrants varied as expected with the left anterior lesion sample showing very little evidence of constructional apraxia, while the right posterior sample showed a high incidence of such deficits. The absolute incidence of significant constructional apraxia in all samples was suprisingly low. This finding might be partially accounted for by the age and general good health of the subjects studied, the relative absence of general cognitive impairment in the majority of subjects, and the discrete nature of the lesions.


Asunto(s)
Apraxias/etiología , Lesiones Encefálicas/complicaciones , Encéfalo/patología , Adolescente , Adulto , Apraxias/diagnóstico , Apraxias/patología , Lesiones Encefálicas/patología , Mapeo Encefálico , Dominancia Cerebral , Humanos , Masculino , Escalas de Wechsler , Heridas Penetrantes
6.
Cortex ; 21(4): 551-65, 1985 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2419031

RESUMEN

Residual, long-term effects of cortical injuries upon speech production are rarely examined. In this study, we examined the articulation and discrimination abilities in twelve subjects who received focal, cortical injuries in Vietnam during 1968-1971. The subjects were divided into two groups based upon the hemisphere (right or left) of lesion. Data revealed the left-hemisphere injured group produced a greater number of articulation and discrimination errors than the right-hemisphere injured group. Articulation errors occurred more often than discrimination errors in both groups. However, a feature analysis revealed the left-hemisphere injured group made predominantly combination errors and the right-hemisphere injured group made predominantly place errors. Taken overall, the data suggest the left-hemisphere injured group may experience residual difficulties with the encoding of phonological units while the right-hemisphere injured group appears to have residual problems that may be related to the spatial correlates of speech.


Asunto(s)
Trastornos de la Articulación/diagnóstico , Daño Encefálico Crónico/diagnóstico , Corteza Cerebral/lesiones , Pruebas de Discriminación del Habla , Adulto , Afasia/diagnóstico , Dominancia Cerebral/fisiología , Lóbulo Frontal/lesiones , Humanos , Masculino , Pruebas Neuropsicológicas , Lóbulo Occipital/lesiones , Lóbulo Parietal/lesiones , Lóbulo Temporal/lesiones
7.
J Neurosurg ; 60(5): 947-54, 1984 May.
Artículo en Inglés | MEDLINE | ID: mdl-6716163

RESUMEN

The occurrence of distant brain damage following an apparent focal missile injury to the brain has not been well documented until computerized tomography scanning demonstrated this phenomenon. Mechanisms of additional or distant damage within the brain may include a high deposit of kinetic energy from the penetrating missile, additional vascular damage, and possibly neuronal and axonal degeneration. Widespread and distant brain changes may explain some instances of late neuropsychological and psychiatric dysfunction or rehabilitation failure following a brain wound. Brain imaging should be used to properly evaluate the full extent of brain damage following wounding.


Asunto(s)
Lesiones Encefálicas/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Heridas Penetrantes/diagnóstico por imagen , Adulto , Lesiones Encefálicas/etiología , Lesiones Encefálicas/patología , Lesiones Encefálicas/psicología , Humanos , Masculino , Medicina Militar , Pruebas Psicológicas , Vietnam , Heridas Penetrantes/complicaciones , Heridas Penetrantes/patología
8.
Life Sci ; 58(21): 1823-32, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8637408

RESUMEN

The present study assessed the safety and efficacy of the cholinesterase inhibitor, velnacrine, for treating the cognitive symptoms of Alzheimer's disease. Patients (N = 236) meeting NINCDS-ADRDA criteria for Alzheimer's disease entered a double-blind, placebo-controlled dose-ranging protocol (30, 75, 150, 225 mg/day each for one week) to identify velnacrine responders (> or = four point improvement on the cognitive subscale of the Alzheimer's Disease Assessment Scale [ADAScog]). After a two week drug washout, velnacrine responders were randomly assigned to their best velnacrine dose or placebo in a six week dose-replication protocol employing the ADAScog and the Clinical Global Improvement scale as primary outcome measures. During dose-replication, intent-to-treat analysis revealed that velnacrine patients scored significantly better than placebo patients on the ADAScog after two (p < 0.004), four (p < 0.025) and six (p < 0.001) weeks of treatment. No significant treatment effect on Clinical Global Improvement scores was observed. The primary adverse event was an asymptomatic elevation of liver transaminases found among 28% of the 236 treated patients. Cholinergic side effects including diarrhea (14%), nausea (11%) and vomiting (5%) were observed and 8% of patients experienced skin rash. The present study identified a subgroup of Alzheimer's patients who demonstrated a significant, but modest, improvement during velnacrine treatment on structured cognitive testing.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Inhibidores de la Colinesterasa/uso terapéutico , Tacrina/análogos & derivados , Anciano , Anciano de 80 o más Años , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Placebos , Tacrina/uso terapéutico
9.
Brain Lang ; 30(2): 338-50, 1987 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3567553

RESUMEN

Two left-handed siblings with developmental stuttering are comprehensively described. The methods of study included speech and language evaluation, neurological and neuropsychological examinations, dichotic listening, auditory evoked responses, electroencephalogram, and CT scan asymmetry measurements. The data from each sibling showed evidence of anomalous cerebral dominance on many of the variables investigated. The CT scan measurements showed atypical asymmetries, especially in the occipital regions. These findings support the theory that stuttering may be related to anomalous cerebral dominance, both on functional as well as structural bases. Implications of anomalous dominance and the resultant effect of hemispheric rivalry on speech fluency are discussed.


Asunto(s)
Dominancia Cerebral , Lateralidad Funcional , Pruebas Neuropsicológicas , Percepción del Habla , Tartamudeo/genética , Tomografía Computarizada por Rayos X , Adolescente , Adulto , Femenino , Humanos , Inteligencia , Masculino , Trastornos Neurocognitivos/genética , Linaje , Tartamudeo/diagnóstico
10.
Qual Manag Health Care ; 2(2): 48-60, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-10133367

RESUMEN

Rising health care costs coupled with an inability to determine what constitutes value in the delivery of health care services lead a group of Cincinnati health care purchasers to seek answers and solutions. The formation of a collaborative effort that includes both purchasers and providers is producing profound changes in the Cincinnati health care market. After one year in operation, data show a significant overall decrease in length of stay, a return to single-digit inflation, and intriguing changes in provider practice patterns.


Asunto(s)
Federación para Atención de Salud , Cuerpo Médico de Hospitales/normas , Pautas de la Práctica en Medicina/estadística & datos numéricos , Gestión de la Calidad Total/organización & administración , Control de Costos/métodos , Recolección de Datos/métodos , Grupos Diagnósticos Relacionados/estadística & datos numéricos , Retroalimentación , Precios de Hospital/normas , Mortalidad Hospitalaria , Kentucky , Tiempo de Internación/economía , Tiempo de Internación/estadística & datos numéricos , Cuerpo Médico de Hospitales/educación , Cuerpo Médico de Hospitales/estadística & datos numéricos , Ohio , Pautas de la Práctica en Medicina/economía
11.
Chirurg ; 70(2): 190-5, 1999 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-10097865

RESUMEN

Between 1984 and 1996 we performed a Mason gastroplasty for the treatment of morbid obesity: 14 patients (average age 40 (26-48) years, body mass index (BMI) 48 (37-71) kg/m2, excessive body weight 67 (41-116) kg). Since the end of 1996 we now apply adjustable laparoscopic gastric banding (lab band): 73 patients (average age 39 (22-64) years, BMI 45 (32-69) kg/m2, excessive body weight 66 (41-116) kg). We compared the early and late results of both methods. Early results: no relevant morbidity or mortality for neither method. Late/intermediate results: reoperation rate for both methods 15%. After an average of 3.7 years the excessive body weight loss (EWL) for gastroplasty was 54 (22-96)%. The EWL after lab band for 24 patients after 12 months was 47 (11-127)% and for 8 patients after 18 months 51 (28-139)%. Since the introduction of the lap band the number of bariatric operations has greatly increased. Nevertheless, the perioperative complication rate has remained low, and the long-term outcome is similar for both methods.


Asunto(s)
Endoscopía/estadística & datos numéricos , Gastroplastia/estadística & datos numéricos , Adulto , Endoscopios , Femenino , Estudios de Seguimiento , Gastroplastia/instrumentación , Humanos , Masculino , Persona de Mediana Edad , Suiza , Resultado del Tratamiento
12.
J La State Med Soc ; 146(5): 213-8, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-8027633

RESUMEN

Vascular dementia and its most common subtype, multi-infarct dementia, are pathologically proven clinical entities. Their prevalence is not as high as previously thought, but they do represent a significant percentage of the population of demented patients. The diagnosis is more difficult to make than is the diagnosis of Alzheimer's disease; however, there are excellent criteria to guide the physician in making the diagnosis. At present the only treatment available is to control the risk factors responsible for the basic disease process; in the majority of cases this requires controlling hypertension.


Asunto(s)
Demencia por Múltiples Infartos , Demencia por Múltiples Infartos/clasificación , Demencia por Múltiples Infartos/diagnóstico , Demencia por Múltiples Infartos/terapia , Humanos
15.
Cortex ; 11(3): 296-8, 1975 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1204370
18.
Internist ; 34(8): 14-6, 18, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10129084

RESUMEN

In response to double-digit health care inflation, Cincinnati employers joined forces to compare costs and outcomes at the city's hospitals. Here's how one hospital is using physician-specific data to improve quality and keep costs down.


Asunto(s)
Evaluación de Resultado en la Atención de Salud/estadística & datos numéricos , Pautas de la Práctica en Medicina/estadística & datos numéricos , Control de Costos/métodos , Recolección de Datos , Grupos Diagnósticos Relacionados/estadística & datos numéricos , Federación para Atención de Salud , Ohio
19.
Manag Care Q ; 2(1): 20-6, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-10132788

RESUMEN

Nationwide, purchaser coalitions are forming to use their buying clout to reform the delivery of health care. In Cincinnati, a collaborative effort between purchasers and providers is producing profound changes in the local health care market. After the first year in operation, data show a significant overall decrease in length of stay (LOS), a return to single-digit inflation, and intriguing changes in provider practice patterns. These results have been achieved through voluntary hospital and physician practice pattern changes without additional contractual allowances, price controls, or utilization management imposed by the initiative. This article explores the development of the Cincinnati initiative, results to date, lessons learned, and future implications.


Asunto(s)
Planes de Asistencia Médica para Empleados/economía , Federación para Atención de Salud/organización & administración , Control de Costos/métodos , Recolección de Datos , Planes de Asistencia Médica para Empleados/estadística & datos numéricos , Precios de Hospital/normas , Relaciones Interinstitucionales , Cuerpo Médico de Hospitales/economía , Cuerpo Médico de Hospitales/normas , Ohio , Evaluación de Resultado en la Atención de Salud/economía , Pautas de la Práctica en Medicina/economía
20.
J Clin Exp Neuropsychol ; 17(3): 325-34, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7650096

RESUMEN

The purpose of this study was to demonstrate spared, long-term sentence priming in individuals with Alzheimer's Disease (AD) using a sentence puzzle task. The sentence puzzle task required a decision--either yes or no--regarding the correctness of an answer supplied for a sentence puzzle. Twelve persons with AD, 12 older controls, and 12 younger controls took part. Speed of response (deciding if a puzzle answer was correct or incorrect) was recorded, with increased speed at retesting after 30-min and 1-week delays used as an index of priming. Individuals with AD demonstrated sentence priming over both a 30-min and 1-week delay, comparable in form to that of controls. In addition, persons with AD were affected by stimulus parameters (correct/incorrect puzzle answers; difficult/easy puzzles) in a similar manner as were controls.


Asunto(s)
Enfermedad de Alzheimer/psicología , Concienciación , Retención en Psicología , Aprendizaje Verbal , Adulto , Anciano , Atención , Femenino , Humanos , Masculino , Recuerdo Mental , Pruebas Neuropsicológicas , Práctica Psicológica , Solución de Problemas , Tiempo de Reacción , Valores de Referencia
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