Background: Bibliographic references support our investigations. Analysis of their use identifies both the information socialization process and how it is built. Objective: To describe bibliography source characteristics that support published investigations in Peruvian biomedical journals. Design: Bibliometric study. Setting: Faculty of Medicine, Universidad Nacional Mayor de San Marcos, Lima, Peru. Bibliographic material: Scientific articles published during 2005-2008 identified in SciELO Peru’s database. Interventions: Only scientific articles were selected, identifying references used and building a database where citation analysis was performed. Main outcome measures: Frequencies, percentages, obsolescence index and Price index. Results: Analysis of 493 articles included 12 475 references; 79% (9 837) consisted in scientific articles citations, 26 journals had 25% (2 458) of citat...

El aporte de Valle y Salvador en el análisis bibliométrico de las tesis sanmarquinas (1) no solo nos brinda un panorama amplio y sincero sobre el estado actual de nuestra producción en pregrado, importante para la reingeniería universitaria; sino que además emplea el programa de análisis y visualización de redes PAJEK (2), ofreciendo una imagen interactiva de la colaboración entre especialidades

Background: Products of research activities in medicine are mainly expressed in scientific journals; these products are subject to quantification and may be registered in specialized databases. Objectives: To determine socialization and interaction of Peruvian researchers and research institutions in order to identify possible critical knots where media intervention might help improving and increasing scientific production in medicine. Design: Bibliometrical study. Institution: Faculty of Medicine, Universidad Nacional Mayor de San Marcos, Lima, Peru. Bibliographic material: Scientific papers published during 2005-2008 in SciELO Peru database. Interventions: Only scientific papers were selected, identifying authorship and institutional affiliation. Authorship and institutional collaboration were analyzed. Main outcome measures: Authors’ signatures index, frequencies, percentages and co...

Objectives: ethics in the research process is an issue little discussed during the undergraduate and therefore should be analyzed to prevent breaches that could affect the development of the researcher in training. Design: Retrospective observational study. Lugar: Facultad de Medicina, Universidad Nacional Mayor de San Marcos. Population: Section of the ‘introduction’ of research works conducted in 2004 in a course curriculum. Interventions: Manually reviewed the prayers of the ‘introduction’ of works, describes the type of copy, the number of works, authors, consultants, copied paragraphs, and the type of information sources and copying. Principal outcome measures: frequencies and percentages of prayers copied and type of copy. Results: It reviewed a total of 24 research papers, with an average of 6 authors and 2 advisers for work, 23 had some evidence of electronic copy, only 8...

Sr. Editor: recientemente leímos el interesante tema de debate sobre ‘irregularidades en la publicación de trabajos científicos’ donde presentan importantes ejemplos de situaciones en las cuales un investigador debe confrontar lo descrito en la teoría como buenas prácticas en investigación, con una realidad llena de presiones y poco conocimiento sobre la materia (1). Los tipos de infracciones a la ética en investigación son muy variadas y están ampliamente descritas en países donde la cultura de publicación es mayor (ver la sección de casos del Committee on Publication Ethics, COPE, www.publicationethics.org.uk); sin embargo y tal como previamente habíamos descrito (2,3), este tipo de infracciones pueden ocurrir desde el pregrado, siendo muy importante detectarlas y corregirlas, pues es el momento donde se forman los futuros investigadores. Por ello, queremos compartir a...

Objective: To quantify student participation in the publication of original contributions in Peruvian medical journals indexed to SciELO Peru. Design: Retrospective observational study. Setting: Archives of the UNMSM Faculty of Medicine and in www.scielo.org.pe. Population: Original papers, short communications (included case reports) and letters to the editor published from 1997 through 2005 in updated quarterly journals. Interventions: Review of authors affiliation (student or professional; sex, university and professional studies of origin), article type and research area (clinical, biomedical, public health). Principal outcome measures: Frequency and percentage of papers with student participation. Results: We included 865 original contributions from four journals; in 4,5% (39) students participated in the authorship, 74% (29/39) were original papers, 10 short communications and ther...

Estimado Sr. Editor, en el volumen 68, número 2, del año 2007, su revista publicó un interesante artículo titulado “Somnolencia y calidad del sueño en estudiantes de medicina de una universidad peruana” (1). Los autores en este artículo describen características importantes del sueño, su calidad y alteraciones en 150 estudiantes de los últimos años de Medicina Humana de la Universidad Peruana Cayetano Heredia (UPCH), comprobando ello a través de un estudio transversal con un muestreo no probabilístico, aplicando como cuestionario de valoración de calidad de sueño el índice de calidad del sueño de Pittsburg (ICSP) en su versión española. Con esta escala determinan que el porcentaje de malos durmientes fue de 58%. La comparación que realizan en el artículo con otros estudios de diferente diseño metodológico, hechos en Colombia o España, señalan que en estos paí...

Objective: To determine life prevalence and characteristics of sleeping paralysis in San Marcos University human medicine fourth year students. Design: Observational, descriptive, crosssectional study. Setting: Faculty of Medicine, San Marcos Major National University. Participants: One hundred thirty nine fourth year medicine students. Interventions: Life and characteristics sleeping paralysis non-concurrent longitudinal study for incidence density, done in August 2005, using a survey type questionnaire validated by experts. Main outcome measures: Sleeping paralysis life prevalence, characteristics, and one month prevalence in medical students. Results: Life prevalence was 56%; prevalence in the last month was 33 events per 100 students; 83,2% had hallucinations during the sleep paralysis events, 58,8% experienced anxiety. Remission was usually spontaneous (64,4%). Conclusions: The prev...

Introduction: Sleep paralysis is a conscious state body immobilization event that appears spontaneously or secondarily to stress situations or to possible bad quality of dream. Objective: To determine medical students association and risk of sleep paralysis in bad sleepers. Design: Analytical, transversal study. Setting: Faculty of Medicine, San Marcos Major National University. Participants: Medical students. Interventions: In May 2006, a non probabilistic sample of medical students was done by a survey including Pittsburg’s Sleep Quality Index and question referred to sleep paralysis. We determined the association between sleep paralysis and dream quality and the sleep paralysis risk in bad sleepers. Chi square test for qualitative variables and student t for quantification were used, with 95% confidence interval. Main outcome measures: Experiences in sleep paralysis and prevalence o...

Neurocysticercosis is a frequent disease, its main location is in the brain parenchyma; however, less than 5% of cases are of spinal location where they produce pseudotumoral or obstructive clinical manifestations. We present the case of a patient admitted due to chronic headache with signs of endrocranial hypertension, without clinical symptoms, and in whom a cysticercotic membrane and cerebrospinal fluid with high glucose consumption (3mg/dL) was obtained during the lumbar puncture study. The finding of a cysticercus of intradural-extramedullary location, during a lumbar puncture is a very rare finding, only described in patients with evident clinical signs. We recommend suspecting it when there is no clinical evidence of spinal cord involvement but there is a suggestion of cerebral cysticercosis and altered cerebrospinal fluid, expanding the study with neuroimaging.

Multiple sclerosis (MS) is an autoimmune disease of the central nervous system (CNS) that can occur in many different ways and progresses generating disability. Less than 5% of cases are pediatric, and even less frequent are the cases of MS in aggressive or highly-active forms. We present the case of a 13-yearold boy who in six months had three attacks, each time more aggressive, with a severe disease burden evidenced by MRI and a rapid progression of his disability. We discuss the diagnostic approach of the MS in the pediatric age, its form of presentation and the evaluation of highly active MS forms.

Introduction. The sign of the hyperdense middle cerebral artery (MCA) evaluated by simple tomography allows predicting ischemic cerebrovascular disease (ICD) with occlusion of a large vessel, however, it is common to identify this sign in residents with high hemoglobin levels without symptoms of ICD. Objectives. To evaluate the correlation between the radiodensity of the MCA and the hemoglobin level in patients with and without ICD, residing in a high-altitude city. Methods. Analytical observational study, including people residing in Cusco (located at 3300 masl) who attended the emergency service and underwent a brain tomography, presenting or not ICD symptoms. ACM radiodensity was measured and correlated with the hemoglobin level. Results. 279 patients were included, the average hemoglobin was 15.1 and standard deviation (DE) of 2.5 mg/dL, in the controls a significant correlation was ...

La neurocisticercosis es una enfermedad frecuente, su principal ubicación es en el parénquima cerebral; sin embargo, menos del 5% de los casos son de ubicación espinal donde producen cuadros clínicos pseudotumorales u obstructivos. Se presenta el caso de un paciente que ingresa por cefalea crónica con signos de hipertensión endocraneana, sin clínica medular, y en quien se obtuvo durante el estudio de punción lumbar una membrana cisticercótica y líquido cefalorraquídeo con gran consumo de glucosa (3mg/dL). El hallazgo de un cisticerco de ubicación intradural-extramedular durante una punción lumbar es un hallazgo muy raro, solo descrito en pacientes con clínica evidente. Los autores recomiendan sospecharla cuando no haya evidencia clínica de compromiso medular pero se tenga sugerencia de cisticercosis cerebral y líquido cefalorraquídeo alterado, ampliando el estudio con ne...

La sangre es una mezcla de componentes que tiene su propia identidad. Una de las propiedades físicas que adquiere es su viscosidad, la cual es la resistencia que ofrece para desplazarse. A diferencia de sus componentes (como glucosa, hemoglobina, colesterol, etc.), la sangre no posee un nivel único de viscosidad, sino que esta es variable debido a diversos factores. Exponemos algunos principios físicos que nos permitirán entender mejor esta dinámica de la viscosidad sanguínea, y su posible aplicación en algunos fenómenos hemodinámicos, así como la complejidad de su medición en la práctica clínica habitual.

La esclerosis múltiple (EM) es una enfermedad crónica del sistema nervioso central (SNC) que desarrolla cuadros clínicos muy variados, puede progresar con brotes, dejar secuelas entre ellos, y tener un lento curso discapacitante. Sin embargo, en algunas personas los brotes tienen compromiso múltiple del SNC, rápido deterioro de la discapacidad, y otros factores de riesgo de mal pronóstico de la enfermedad. Aunque no hay consenso sobre su definición, estas características indican que se trataría de una EM de alta actividad. Se describe la dificultad para conciliar una definición apropiada de EM de alta actividad y la necesidad de usar de forma precoz drogas de alta eficacia en aquellas EM de alta actividad que se presentan desde el inicio de la enfermedad.

La esclerosis múltiple (EM) es una enfermedad crónica del sistema nervioso central (SNC) que desarrolla cuadros clínicos muy variados, puede progresar con brotes, dejar secuelas entre ellos, y tener un lento curso discapacitante. Sin embargo, en algunas personas los brotes tienen compromiso múltiple del SNC, rápido deterioro de la discapacidad, y otros factores de riesgo de mal pronóstico de la enfermedad. Aunque no hay consenso sobre su definición, estas características indican que estamos ante una EM de alta actividad. Poder identificar la EM de alta actividad de forma precoz nos permite individualizar su tratamiento y usar drogas de alta eficacia. Nosotros describimos la dificultad para conciliar una definición apropiada de M de alta actividad y la necesidad de usar de forma precoz drogas de alta eficacia en aquellas EM de alta actividad que se presentan desde el inicio de la...

Blood is a mixture of components that has its own identity. One of the physical properties that it acquires is its viscosity, which is the resistance it offers to move. Unlike its components (such as glucose, hemoglobin, cholesterol, etc.), blood does not have a single level of viscosity, but it is variable due to various factors. We present some physical principles that will allow us to better understand these dynamics of blood viscosity, and its possible application in some hemodynamic phenomena, as well as the complexity of its measurement in routine clinical practice.

Objetivos. Evaluar la correlación y concordancia entre el Examen Nacional de Medicina de Perú (ENAM) y el Promedio Ponderado Universitario (PPU) en estudiantes egresados del pregrado de medicina en el periodo 2007 a 2009. Materiales y Métodos. Se llevó a cabo un análisis secundario de datos, empleando el registro de inscritos en las convocatorias a los procesos del Servicio Rural Urbano Marginal en Salud de Perú (SERUMS) de los años 2008 a 2010, obteniéndose las calificaciones en el ENAM y el PPU. Se efectuó un análisis descriptivo por medio de medianas y percentiles 25 y 75 (p25/p75); la correlación entre ambas calificaciones se realizó por medio del coeficiente de correlación de Spearman; asimismo, se efectuó un análisis de regresión lineal y la concordancia fue medida a través del coeficiente de correlación y concordancia de Bland y Altman. Resultados. Se incluyeron ...

Blood is a mixture of components that has its own identity. One of the physical properties that it acquires is its viscosity, which is the resistance it offers to move. Unlike its components (such as glucose, hemoglobin, cholesterol, etc.), blood does not have a single level of viscosity, but it is variable due to various factors. We present some physical principles that will allow us to better understand these dynamics of blood viscosity, and its possible application in some hemodynamic phenomena, as well as the complexity of its measurement in routine clinical practice.

Objective: We aimed to determine the correlation between blood viscosity and cerebral blood flow in people acclimated to chronic hypoxia who have high blood viscosity levels. Materials and methods: A Prospective observational study was conducted in asymptomatic young adults living in Cusco (3399 m altitude). All participants were examined at low and high shear rates (75 and 300 s−1) for simulating the dynamic component of blood viscosity. A transcranial Doppler study of the middle cerebral artery was performed to measure systolic, diastolic, and mean flow velocities (FVs), as well as resistance and pulsatility indexes (PIs). Results: One hundred and thirty-one participants were included. Median viscosity levels were 5.01cP (interquartile range [IQR]: 4.45–5.73cP) at 300 s−1 and 6.16 cP (IQR: 5.58-7.20 cP) at 75 s−1, mean FV was 57 cm/s (IQR: 50–65 cm/s), and the PI was 0.91 (0....