Placental-like alkaline phosphatase. Re-evaluation of the tumor marker with exclusion of smokers.

This report demonstrates that smoking is a major factor of nonspecific elevation of the tumor marker placental-like alkaline phosphatase (PLAP). In 98 healthy nonsmokers the mean of the enzyme activity was determined as 0.068 U/L (range, +/- 2 SD 0-0.

Interference of O.C.T. embedding compound with hormone receptor assays.

The interference of O.C.T.

Optimizing reference values for the measurement of alpha 1-antitrypsin in serum: comparison of three methods.

We studied three methods (rate nephelometry, radial immunodiffusion, and trypsin-inhibitory capacity) for their ability to detect those individuals with a deficiency of alpha1-antitrypsin. The phenotype represented in 170 serum samples was determined by isoelectric focusing as the reference method. All three methods correctly identified Pi Z, Pi S, and Pi SZ phenotypes but varied in their ability to detect Pi MZ and Pi MS phenotypes.

Erythrocyte age-fractionation using a Percoll-Renografin density gradient: application to autologous red cell antigen determinations in recently transfused patients.

A rapid technic for the age-fractionation of human erythrocytes into reticulocyte-enriched (young) red blood cells and reticulocyte-poor (old) red blood cells using an isopycnic density gradient centrifugation through Percoll-Renografin was evaluated for use in autologous red blood cell antigen determinations in multiply-transfused patients. The fractionation was demonstrated by statistically significant density-related changes in pyruvate kinase and acetylcholinesterase activities (P = 0.002 and 0.