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1.
Opt Lett ; 41(1): 167-70, 2016 Jan 01.
Article in English | MEDLINE | ID: mdl-26696185

ABSTRACT

We report the temperature modulation of the optical transmittance of a few layers of graphene (FLG). The FLG was heated either by the Joule effect of the current flowing between coplanar electrodes or by the absorption of a continuous-wave 532 nm laser. The optical signals used to evaluate the modulation of the FLG were at 633, 975, and 1550 nm; the last wavelengths are commonly used in optical communications. We also evaluated the effect of the substrate on the modulation effect by comparing the performance of a freely suspended FLG sample with one mounted on a glass substrate. Our results show that the modulation of the optical transmittance of FLG can be from millihertz to kilohertz.

2.
Rev. mex. ing. bioméd ; 36(2): 131-142, Jan.-Apr. 2015. ilus
Article in Spanish | LILACS-Express | LILACS | ID: lil-753799

ABSTRACT

En este trabajo se presenta el diseño e implementación de un electrodo capacitivo de no contacto para la detección de biopotenciales en el cuerpo humano. Se presentan los circuitos eléctricos, el criterio de selección del amplificador operacional en base al análisis de la resistencia óptima de ruido, se describe el montaje físico, se presentan las señales obtenidas con este y la evaluación de su desempeño en base a la relación señal a ruido S/N. Se muestra el desempeño de diversos amplificadores operacionales y se demuestra la versatilidad del electrodo para detectar diversos biopotenciales realizando ajustes en los valores de dos componentes eléctricos del electrodo.


In this work the design and implementation of a capacitive non-contact electrode for detecting biopotentials in the human body is presented. Electrical circuits, the selection criteria of the operational amplifier based on the analysis of the optimal noise resistance are presented, the physical assembly is described and the signals obtained and evaluation of its performance are presented based on the signal-to-noise ratio S/N. We show the performance of several operational amplifiers and it is shown the versatility of the electrode to detect several biopotentials making adjustments to the values of two electrical components of the electrode.

3.
Rehabilitación (Madr., Ed. impr.) ; 46(1): 30-35, ene.-mar. 2012.
Article in Spanish | IBECS | ID: ibc-96501

ABSTRACT

Introducción. La enfermedad cerebrovascular es la tercera causa de muerte y la causa más frecuente de discapacidad del adulto. El déficit motor es la secuela más frecuente superando el 50%. La rehabilitación motora se ve limitada por procesos inflamatorios locales, por lo tanto el uso de cremas con acción antiinflamatoria asociado a la fisioterapia habitual pudiera ser útil en estos pacientes. Material y métodos. Se realizó un ensayo clínico controlado con placebo en dos grupos paralelos para demostrar la eficacia del Folrex(R) en la rehabilitación motora de los miembros superiores en los pacientes con enfermedad cerebrovascular isquémica aguda. Los criterios de inclusión, edad entre 18 y 90 años de menos de 24 horas de evolución y con una puntuación superior de 4 en NIHSS, apoyo familiar y consentimiento a participar en esta investigación. El tamaño muestral necesario fue de 20 pacientes para cada grupo. El criterio principal de evaluación fue la escala de Fugl-Meyer, con evaluaciones al inicio, al quinto día y al mes. Resultados. Hubo una mejoría significativa (p<0,04) del estado motor según la escala de Fugl-Meyer en el grupo de estudio en comparación con el control. Conclusiones. Folrex(R) en crema es eficaz en la rehabilitación motora de los miembros superiores de los pacientes con enfermedad cerebrovascular isquémica aguda (AU)


Introduction. Cerebrovascular disease is the third most common cause of death and the most common cause of disability in the adult. Motor deficit is one of the most significant sequels, this being found in over 50% of the patients. Motor rehabilitation is limited by local inflammatory conditions, so that topical application of anti-inflammatory creams, associated to the usual physiotherapy, may be useful in these patients. Material and methods. A placebo-controlled trial performed was performed in two parallel groups to demonstrate the efficacy of Folrex(R) in motor rehabilitation of the upper limbs in patients with acute ischemic cerebrovascular disease. Inclusion criteria were age from 18 to 90 years, less than 24hours of evolution, score on NIHSS superior to 4, adequate family support, with explicit consent to participate in this study obtained from patients and their families. The necessary sample size was 20 patients per group. The main evaluation criteria was the Fugl-Meyer scale, with evaluations at the onset, on the first day and at one month. Results. There was significant improvement in motor function (P<0.04) on the Fugl-Meyer scale, compared to the control group. Conclusions. Folrex(R) cream is effective in motor rehabilitation of the upper limbs in patients with acute ischemic cerebrovascular disease (AU)


Subject(s)
Humans , Male , Female , Adolescent , Young Adult , Adult , Middle Aged , Aged , Aged, 80 and over , Cerebral Infarction/complications , Motor Activity/physiology , Cerebrovascular Disorders/complications , Cerebrovascular Disorders/rehabilitation , /trends , Upper Extremity/injuries , Placebo Effect
11.
Neurologia ; 15(7): 269-73, 2000.
Article in Spanish | MEDLINE | ID: mdl-11075574

ABSTRACT

OBJECTIVE: To determine the prevalence of Parkinson's disease in an urban area of Havana City province, Cuba. BACKGROUND: Parkinson's disease is one of the most frequent chronic neurodegenerative diseases in the elderly. Prevalence varies widely between different geographic areas and type of studies. To the author's knowledge, there are not epidemiological data on Parkinson's disease in Cuban population that allows a real estimation of the true magnitude of the disease. PATIENTS AND METHODS: A "door-to-door" population study was carried out between November and December 1997. The area total population aged 15 years and over (n = 17.784) was interviewed and examined during the first phase of the study. This phase was performed by the 33 family doctors practicing in that area. An experienced neurologist previously trained the family doctors on making Parkinson's disease diagnosis. Diagnosis was based on the Brain Bank Society criteria. In order to make a definitive diagnosis of Parkinson's disease every subject that received such a diagnosis during the first phase was re-evaluated by two experienced neurologists. Those subjects with final diagnosis of Parkinson's disease were asked about family history of the disease. Prevalence rates were calculated according to sex, age group, color of the skin and smoking status. RESULTS: A total of 24 subjects received the final diagnosis of Parkinson's disease, yielding a population prevalence rate of 135 x 100,000 inhabitants. Eight subjects (33.3%) received a diagnosis of Parkinson's disease for the first time (de novo cases). Subjects with white color of the skin and non-smoking subjects showed a statistically significant higher prevalence of Parkinson's disease than subjects with non-white color of the skin and non-smokers respectively. Only 3 (12.5%) subjects reported a family history of Parkinson's disease. CONCLUSION: The population of this area has a low prevalence rate of Parkinson's disease compared to that reported in other populations. The observed low frequency of family history of the disease suggests that the main determinants of Parkinson's disease are environmental factors yet to be identified.


Subject(s)
Parkinson Disease/epidemiology , Adolescent , Adult , Aged , Aged, 80 and over , Cuba/epidemiology , Ethnicity/statistics & numerical data , Female , Humans , Male , Middle Aged , Neurologic Examination , Prevalence , Smoking/epidemiology , Urban Population
12.
Rev Neurol ; 30(10): 935-8, 2000.
Article in Spanish | MEDLINE | ID: mdl-10919190

ABSTRACT

INTRODUCTION: Since the 1980s, in relation to the spread of AIDS, there has been an enormous increase in cryptococcosis, a mycotic disorder which usually affects the central nervous system (CNS). This disease is caused by Cryptococcus neoformans, a microorganism acquired by inhalation of bird excrement. This germ produces a capsule which protects it from phagocytosis, can synthesize melanin which acts as an antioxidant of the cytotoxic lymphocytes and can reproduce at body temperature. Clinically it may show as chronic or subacute meningitis and/or encephalitis, as endocranial hypertension or as an intracranial space occupying lesion (crytococcoma). To establish the diagnosis, Chinese ink, culture and the latex agglutination test are useful. Treatment is with amphotericin B associated or not with fluocytokine and fluconazole, the protocol used depending on the clinical form. OBJECTIVE: To review the most up-to-date literature on cryptococcosis of the CNS to study the condition in relation to five cases. CLINICAL CASES: We report five patients with cryptococcosis of the CNS diagnosed and treated in the Instituto Nacional de Neurología y Neurocirugia de la Habana, Cuba, showing an increase in the frequency of the occurrence of cases not related to HIV infection, great variety of clinico-humoral presentation and the characteristics of the treatment given. CONCLUSION: Cryptococcosis can be cured completely when the condition is diagnosed early; without treatment it is invariably fatal.


Subject(s)
Brain Diseases/microbiology , Carbon , Cryptococcosis/diagnosis , Cryptococcus neoformans/isolation & purification , Adult , Amphotericin B/therapeutic use , Antifungal Agents/therapeutic use , Brain Diseases/diagnosis , Brain Diseases/drug therapy , Cerebrospinal Fluid Proteins/analysis , Coloring Agents , Cryptococcosis/drug therapy , Female , Fluconazole/therapeutic use , Humans , Latex Fixation Tests/methods , Male , Middle Aged , Tomography, X-Ray Computed
13.
Neurología (Barc., Ed. impr.) ; 15(7): 269-273, ago. 2000.
Article in Es | IBECS | ID: ibc-5697

ABSTRACT

Objetivo: Determinar la prevalencia de la enfermedad de parkinson en un área urbana de la provincia Ciudad de La Habana, Cuba. Fundamento: La enfermedad de Parkinson es una de las enfermedades crónicas neurodegenerativas más frecuentes del anciano. La prevalencia de dicha enfermedad varia notablemente entre las distintas áreas geográficas y los estudios realizados. Hasta el momento no existen datos epidemiológicos sobre la verdadera magnitud de la enfermedad de Parkinson en población cubana. Pacientes y método: Se realizó un estudio poblacional de tipo "puerta a puerta". En una primera etapa se entrevistó y examinó a toda la población mayor de 15 años de edad (17.784 habitantes) por parte de los médicos de la familia que brindan servicios a la población residente en el área de salud del Policlínico Corintia. Dichos médicos habían recibido con anterioridad un entrenamiento estandarizado por parte de un médico especialista en neurología. El diagnóstico de enfermedad de Parkinson se realizó según los criterios clínicos de la Sociedad del Banco de Cerebros del Reino Unido. Todos los sujetos con diagnóstico de enfermedad de Parkinson en la primera etapa fueron evaluados en una segunda etapa por dos expertos neurólogos para confirmar dicho diagnóstico. Se indagó sobre la historia familiar de enfermedad de Parkinson y se calculó la tasa de prevalencia de la enfermedad según grupo de edad, sexo, color de la piel y hábito tabáquico. Resultados: Un total de 24 sujetos recibieron el diagnóstico definitivo de enfermedad de Parkinson para una tasa de prevalencia poblacional de 135 * 100.000 habitantes. Ocho casos (33,3 por ciento) recibieron por primera vez dicho diagnóstico (casos de novo). En los sujetos de piel blanca y los no fumadores se apreciaron tasas de prevalencia de enfermedad de Parkinson significativamente más elevadas que los sujetos de piel no blanca y los no fumadores, respectivamente. Sólo tres (12,5 por ciento) de los 24 casos diagnosticados presentaban historia familiar de enfermedad de Parkinson. ConclusiÓn: La población cubana residente en esta área posee una baja tasa de prevalencia de enfermedad de Parkinson comparada con la hallada en poblaciones de otros países. En esta población existe una mayor frecuencia de enfermedad de Parkinson en individuos de color de la piel blanca y en fumadores. La observada baja frecuencia de historia familiar de enfermedad de Parkinson sugiere que los principales determinantes de esta enfermedad son factores ambientales aún por identificar (AU)


Subject(s)
Middle Aged , Adult , Adolescent , Aged, 80 and over , Aged , Male , Female , Humans , Tobacco Use Disorder , Urban Population , Prevalence , Parkinson Disease , Neurologic Examination , Cuba , Ethnicity
14.
J Pediatr ; 136(6): 809-17, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10839881

ABSTRACT

OBJECTIVES: For acutely ill children living in less than optimal environments, mothers and pediatricians may have a heightened perception of illness severity, a lower specificity of clinical judgments, and a tendency to over-utilize resources. We examined the mother-child interaction in order to understand the relation of less optimal environments to clinical judgment and resource use. STUDY DESIGN: At the 2-week and 6-, 15-, and 24-month well child visits of 316 children, the mother-well child interaction was assessed by using the Biringen's Emotional Availability Scales (EAS). Data were gathered regarding maternal depression and sense of competence, infant temperament, maternal social support, life events, the home environment, and demographics. At ill visits, the mother-ill child interaction was assessed by using the EAS, and mothers and pediatricians independently assessed illness severity using the Acute Illness Observation Scales. Resource use during the illness was evaluated. RESULTS: One thousand nine hundred eight-three acute illnesses were assessed. A less optimal mother-child interaction was significantly (P <.05 for all comparisons) associated with poorer reliability of mothers' judgments, lower specificity of mothers' judgments (71% vs 85%) and pediatricians' judgments (92% vs 97%), and greater use of resources (eg, for hospitalizations, 2.6% of visits vs 0.7%). Adverse maternal, infant, and demographic characteristics were associated with a less optimal mother-well child (r = 0.68) and mother-ill child (r = 0.80) interaction, a heightened perception of illness severity, and greater resource use. CONCLUSION: Less optimal environments adversely affect the mother-child interaction; a poor mother-child interaction is correlated with low specificity of clinical judgment and over-utilization of resources.


Subject(s)
Acute Disease/psychology , Mother-Child Relations , Child, Preschool , Humans , Infant , Infant, Newborn , Mothers/psychology , Reproducibility of Results , Sensitivity and Specificity , Socioeconomic Factors
15.
La Habana; s.n; 1999. 10 p. tab, graf.
Non-conventional in Spanish | LILACS | ID: lil-259514

ABSTRACT

El nifedipino es un medicamento empleado con éxito en el control de la hipertensión arterial que se produce en cantidades apreciables en los Laboratorios MedSol. Como parte de los esfuerzos que se realizan para disminuir los costos de calidad de los fármacos, el presente trabajo desarrolla un procedimiento analítico que emplea como solvente de extracción el etano de producción nacional, basándose en a propiedad de este producto de presentar un máximo de absorción alrededos de 342 nm con sensibilidad apropiada.Se sustitituye de esta manera el dioxido, reactivo de importancia y toxicidad comprobada para el organismo humano. La técnica ha sido introducida en la práctica durante 18 meses con resultados satisfactorios en cuanto a eficiencia. Se ha cumplido así con los procedimientos establecidos al efecto en los Laboratorios MedSol que se apoya en lo relacionado con este aspecto de la USP 23


Subject(s)
Hypertension/drug therapy , Nifedipine
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