Norberto Oviedo

El presente trabajo tiene como objetivo visualizar estrategias, métodos, técnicas y algunas formas de pensamiento que emplean los estudiantes de primaria y secundaria en la resolución de situaciones problemas de combinatoria. Para ello, se aplicó un cuestionario y una entrevista individualizada a cinco estudiantes de primaria y cinco de secundaria, con el propósito de determinar la manera en que ellos lograban enfrentarse a dichas situaciones

The rate of choledocholithiasis at the time of elective surgery after mild acute biliary pancreatitis is still unclear because it decreases rapidly after the onset. The aims of this study are as follows: (1) To investigate whether the incidence of choledocholithiasis in mild biliary pancreatitis is higher than in patients with symptomatic cholelithiasis. (2) To evaluate the usefulness of intraoperative cholangiography in the diagnosis of unsuspected choledocholithiasis in mild pancreatitis. Prospective study including 130 patients undergoing laparoscopic surgery and classified into two groups: mild biliary pancreatitis (n = 44) and symptomatic cholelithiasis (n = 86). Choledocholithiasis was evaluated by endoscopic cholangiopancreatography, magnetic resonance, and intraoperative cholangiography. Preoperatively, choledocholithiasis was identified in five patients with symptomatic cholelithiasis and two with biliary pancreatitis (5.81 vs 4.54%; p = 0.472). In 117 cases (90%), intraoperative cholangiography was successfully performed, identifying unsuspected choledocholithiasis in five patients of the colelithiasis group and in three in the group of pancreatitis (5.81 vs 6.81%; p = 0.492). The total number of patients with choledocholithiasis in the whole series was 15 (11.5%); 11.6% in colelithiasis group vs 11.4% in biliary pancreatitis group; p = 0.605. The rate of choledocholithiasis was not significantly different between the groups of patients with mild acute biliary pancreatitis and symptomatic cholelithiasis. Intraoperative cholangiography identified unsuspected choledocholithiasis in 6.81% of patients with mild acute biliary pancreatitis.