Historia de las ciudades en los países de economía avanzada

Tomado de: Cuadernos de la Sociedad Venezolana de Planificación, v. 3, No 7-8, junio-julio 1964

Macroeconomía de la urbanización brasileña

Tomado de: Pesquisa e Planejamento Económico, v. 3, n. 3, octubre 1973

La ciudad y la política

Tomado de: Estudios Sociales Centroamericanos, No 4, enero-abril 1973

Niveles de rendimiento y factores psicológicos en deportistas en formación. Reflexiones para entender la exigencia psicológica del alto rendimiento.

[ES] A pesar de que diferentes trabajos se han esforzado en identificar las variables que pueden estar en la base del alto rendimiento deportivo, no existe acuerdo todavía acerca de cuáles pueden ser verdaderamente las más relevantes. El presente trabajo de carácter exploratorio pretende comprobar la posible existencia de diferencias significativas a nivel psicológico, tomando como referencia algunas de las pruebas que habitualmente utilizan los psicólogos del deporte (POMS, CPRD, BREQ,...).

Análisis de las caracterísicas psicológicas y la toma de decisiones en un grupo de nadadores

[ES] La presente investigación tiene el objetivo de analizar las características psicológicas relacionadas con el rendimiento deportivo y el estilo de toma de decisiones de 70 nadadores, relacionándolos en función del sexo, nivel deportivo y categoría deportiva. Utilizando el cuestionario Características Psicológicas relacionadas con el Rendimiento Deportivo (CPRD) (Gimeno, 1999) y el Cuestionario de Estilo de Toma Decisiones (CETD) (Ruiz, Graupera, y Sánchez, 2000).

Case-control analysis on metformin and cancer of the esophagus

PURPOSE Metformin use has been associated with decreased cancer risks, though data on esophageal cancer are scarce. We explored the relation between use of metformin or other anti-diabetic drugs and the risk of esophageal cancer. METHODS We conducted a case-control analysis in the UK-based general practice research database (GPRD, now clinical practice research datalink, CPRD). Cases were individuals with an incident diagnosis of esophageal cancer between 1994 and 2010 at age 40-89 years. Ten controls per case were matched on age, sex, calendar time, general practice, and number of years of active history in the GPRD prior to the index date. Various potential confounders including diabetes mellitus, gastro-esophageal reflux, and use of proton-pump inhibitors were evaluated in univariate models, and the final results were adjusted for BMI and smoking. Results are presented as odds ratios (ORs) with 95 % confidence intervals (CI). RESULTS Long-term use (≥30 prescriptions) of metformin was not associated with a materially altered risk of esophageal cancer (adj. OR 1.23, 95 % CI 0.92-1.65), nor was long-term use of sulfonylureas (adj. OR 0.93, 95 % CI 0.70-1.23), insulin (adj. OR 0.87, 95 % CI 0.60-1.25), or of thiazolidinediones (adj. OR 0.71, 95 % CI 0.37-1.36). CONCLUSION In our population-based study, use of metformin was not associated with an altered risk of esophageal cancer.

Metformin and the risk of head and neck cancer: a case-control analysis

AIMS Metformin use has been associated with a decreased risk of some cancers, although data on head and neck cancer (HNC) are scarce. We explored the relation between the use of antidiabetic drugs and the risk of HNC. METHODS We conducted a case-control analysis in the UK-based Clinical Practice Research Datalink (CPRD) of people with incident HNC between 1995 and 2013 below the age of 90 years. Six controls per case were matched on age, sex, calendar time, general practice and number of years of active history in the CPRD prior to the index date. Other potential confounders including body mass index (BMI), smoking, alcohol consumption and comorbidities were also evaluated. The final analyses were adjusted for BMI, smoking and diabetes mellitus (or diabetes duration in a sensitivity analysis). Results are presented as odds ratios (ORs) with 95% confidence intervals (CIs). RESULTS Use of metformin was neither associated with a statistically significant altered risk of HNC overall (1-29 prescriptions: adjusted OR 0.87, 95% CI 0.61-1.24 and ≥ 30 prescriptions adjusted OR 0.80, 95% CI 0.53-1.22), nor was long-term use of sulphonylureas (adjusted OR 0.87, 95% CI 0.59-1.30), or any insulin use (adjusted OR 0.92, 95% CI 0.63-1.35). However, we found a (statistically non-significant) decreased risk of laryngeal cancer associated with long-term metformin use (adjusted OR 0.41, 95% CI 0.17-1.03). CONCLUSIONS In this population-based study, the use of antidiabetic drugs was not associated with a materially altered risk of HNC. Our data suggest a protective effect of long-term metformin use for laryngeal cancer.