The incidence of intussusceptions prolapsing rectally is high in this series. It can present in the absence of the cardinal symptoms of intussusception. A high index of clinical suspicion is necessary to make the diagnosis. AER is often successful and must be attempted in children who do not have contraindications for this procedure.

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Systematic studies on the RBa 2 Cu 3Ϫx M x O 7 ͑RϭSm, Dy; M ϭFe, Ni, Zn͒ system were carried out in order to determine the effect of the rare-earth ionic size and magnetic moment on the T c suppression rate. The phases were characterized by powder x-ray diffraction ͑XRD͒, resistivity, and ac susceptibility measurements. XRD studies indicate a higher solubility limit of M ions in the SmBa 2 Cu 3Ϫx M x O 7 ͓Sm-123(M )͔ system as compared to the DyBa 2 Cu 3Ϫx M x O 7 ͓Dy-123(M )͔ system. Resistivity and ac susceptibility studies indicate that the T c suppression rate for a given M ion depends on the ionic radius of the rare earth (R) and is higher for larger rare earths. The trend in T c suppression as a function of concentration (x) shows deviation from Abrikosov-Gor'kov behavior. A metal-insulator transition is observed at higher dopant concentrations, and the semiconducting phases are found to obey the Mott's variable range hopping mechanism of conduction. The parameters related to hopping conduction; viz., the characteristic temperature ͑T 0 ͒, localization length (a), hopping range (R), and hop energy (W) have been calculated, and a comparative study of the variation of these parameters in the two systems has been made.

Surgery alters the body's homeostatic balance and defense mechanisms. In adults transient postoperative cellular and humoral immunosuppression after different degrees of operative stress has been reported. In children the immunologic consequences of operations are not elaborated. This study investigates the effect of minor and major surgery on early nonspecific immune response in terms of neutrophil counts and function. Forty-three children undergoing minor and major elective procedures were studied. Blood samples were collected before, immediately after, and 72 h after surgery. Total white cell count, differential neutrophil count, and neutrophil phagocytic function were studied using nitroblue tetrazolium test. Children were divided into two groups-group 1 underwent minor surgery and group 2 major surgery. In group 1 there was a significant drop in total counts after surgery, but in group 2 total counts were not affected. In both groups, the percentage of neutrophils increased immediately after surgery but fell to near or less than preoperative levels 72 h after surgery. However, the assessment of neutrophil functions by nitroblue tetrazolium test in both unstimulated and stimulated forms revealed it to be unchanged in group 1. In group 2 the unstimulated neutrophil function was elevated 72 h after surgery, whereas stimulated function was elevated immediately after surgery. Minor surgery does not alter the early nonspecific immune response. However, major surgery seems to induce a transient increase in neutrophil phagocytic activity.