Serum immunoreactive calcitonin concentrations in hepatocellular carcinoma.

Having found raised serum calcitonin concentrations in 94% of patients with hepatocellular carcinoma when using a dextran-coated-charcoal radio-immunoassay, we have now repeated the study, using a double-antibody radio-immunoassay, in 102 further patients with hepatocellular carcinoma and 35 matched controls. Serum immunoreactive calcitonin concentrations (iCT) in the controls ranged from 10 to 310 pg/ml (mean 154.6 pg/ml). Values in the tumour patients ranged from 10 to 1,650 pg/ml (mean 302.6 pg/ml). The mean figures were significantly higher in the tumour patients (P less than 0.001), 35.5% of them having values above 310 pg/ml. In 65 of the patients serum iCT concentrations were also determined by dextran-coated-charcoal radio-immunoassay. Values ranged from 10 to 10,780 pg/ml (mean 2,179 pg/ml). If 1,000 pg/ml is taken as the upper limit of normal, 69% of the patients had raised iCT concentrations. There was a good correlation (r = 0.67; P less than 0.001) between serum iCT values measured with both methods in 50 patients. If measured by the double-antibody radio-immunoassay method, the serum calcitonin value is not useful as a marker for hepatocellular carcinoma.

Patterns of maternal care in lemurs. III. Lemur variegatus.

Lemur fulvus, L. catta, and L. variegatus differ markedly in the details of mother-infant relations. Do these differences account for those seen in adult life? We hope to determine this through interspecific cross-fostering. Here we describe the normal pattern of rearing of 5 infants among two groups of 2 and 5 adult L. variegatus, reared in the laboratory. The descriptions cover the first 7 months of life, and include the effects of maternal separation at 150 days of age, when estrus normally disrupts maternal care. The principal finding is that in the mother's absence young turn more to other adults than to their siblings, who are, apparently, not adequate social substitutes for adults.