["In 27 infected neonates (16 boys and 11 girls) with birth weight ranged from 1200 to 4500 g (mean 2670 +/- 827 g) and gestational age from 31 to 41 weeks (mean 36.7 +/- 4.1), among them 11 (41%) with birth asphyxia, between 1 and 7 day of life flow cytometric immunophenotyping of the relative sizes of natural killer cells (CD3-/CD16-56+) using monoclonal antibodies of Becton Dickinson were made. The following infections were diagnosed in the neonates: bacterial septicemia (gram-positive in 13 cases, gram-negative in 5 cases), pneumonia in 6 cases and purulent meningitis in 3 cases. Control group consisted of full-term, healthy, eutrophic neonates born in Military Medical Academy in Lódź between 1994-95 years, in which immunological studies were made with the same method and dr Banasik, agreed for using her results for statistical analysis. It was stated, that in infected full-term neonates the mean relative size of NK cells was 10.7 +/- 5.1% and in prematures 12.8 +/- 7.2% and did'n differ significantly from the control. Kind of infection had no significant influence on the mean relative size of these cells, because in septic neonates was 11.7 +/- 5.7% and in other infected babies 11.6 +/- 7.2%. It was found that infected neonates without respiratory insufficiency and shock had significantly higher (13.2 +/- 6.4%) relative size of NK cells than healthy. The lowest value (7.0 +/- 4.8%) of NK cells during infections in dead neonates were noted (4 cases, among them 2 septic with shock and 2 pneumonic prematures with intraventricular haemorrhages)."] Do [ The influence of severe infections on the natural killer cells in neonates with vary gestational age ]?