A case with benign renal leiomyoma examined by all the imaging techniques currently available is described. The aspects were conflicting, particularly with regard to sonography and magnetic resonance imaging, and the sole technique which provided more reliable information was the CT scan.

lymphosarcoma as a lead point in intussusception in an older child played a major role in recommending a hemicolectomy in the case pre¬ sented. It was gratifying, however, to find a fecalith as the "mass" in this boy's cecum. Abscess in ChildrenPyogenic liver abscesses are infrequent in pediatric patients, although they are said to occur in debilitated children1 and in children with chronic granulomatous disease.2 We report here five cases of pyogenic liver abscess in previously healthy children, diagnosed in a period of nine months at the Hospital de Crian\l=c;\aConcei \l =c;\\l =a~\o, Porto Alegre, Brazil.

Rats were subjected to partial hepatic lobectomy with removal of about two thirds of the liver either by scalpel, by CO₂ laser, or by electrical diathermy. Macroscopic examinations of livers at various days after surgery indicated that CO₂ laser surgery results in minor tissue damage, reduced complications from inflammation and infections, and faster healing compared to electrical diathermy, but it is less satisfactory than the scalpel with respect to all these parameters. Rat liver regeneration was followed at the molecular level by measuring the changes of protein biosynthesis activity in the liver, as monitored by modifications of ribosome organization. Activation of the protein biosynthesis process started 1 day after surgery when hepatectomy was performed by scalpel, while 2 days were required when CO₂ laser or electrical diathermy were used instead.