Objective To investigate the changes in cellular immune function and biochemical indicators of conventional submarine crew both before and after prolonged deployment at sea.Methods Sixtytwo submariners were recruited as the subjects of our study.Detections were made on T lymphocyte subpopulation and NK cell (CD3 + , CD4 + , CD8 + , CD4 +/CD8 + and NK cells) , heptorenal function as well as 13 biochemical indicators [blood glucose (Glu), aspartate amninotransferase (AST), alanine aminotransferase (ALT), AST/ALT, UREA, creatinine (CREA), potassium (K), sodium (Na) and chlorine (Cl), calcium (Ca), magnesium (Mg), phosphorus (P) and iron (Fe)].Results As compared with those before prolonged deployment at sea, CD3 + levels in the T lymphocyte subpopulation after prolonged deployment at sea (67.02％ ± 7.30％ and 68.91％ ± 8.15％ respectively) , CD4 + levels(33.59％ ± 5.61％ and 36.87％ ± 3.65 ％ respectively) , and CD4 +/CD8 + levels (1.22 ± 0.45, 1.46 ± 0.52 respectively) , were all significantly increased (P ＜-0.05).However, CD8 + levels were obviously decreased(27.32％ ± 8.21％ ,25.25％ ± 4.38％) (P ＜ 0.05).Blood glucose levels were obviously increased [(3.68 ± 0.85) mmol/L and (4.38 ± 1.15) mmol/L respectively] (P ＜ 0.05).Ca levels were also elevated [(2.48 ± 0.11) mmol/L and (2.54 ± 0.12) mmol/L respectively] (P ＜ 0.05).Na levels were respectively [(141.08 ± 5.75) mmol/L,(138.08 ± 2.86)mmol/L] , C1 levels were obviously decreased, which were respectively [(103.12 ± 3.09)mmol/L and(98.89 ±4.28)mmol/L] (P ＜0.01), and Fe levels were also obviously decreased, which were [(23.14 ± 6.75) μmol/L and (21.54 ± 7.34) μmol/L] respectively (P ＜ 0.05).Though biochemical indicators of heptorenal function were elevated to various extents, no statistical differences could be noticed (P ＞ 0.05).Conclusions The immune response of the conventional submariners during this prolonged deployment at sea was enhanced, the blood glucose and Ca levels were elevated, but Fe, Na and Cl levels were decreased, indicating that nutritional components should be adjusted in future submarine deployments at sea,and attention should be paid to the changes in blood glucose, so as to ensure the mental health of the submariners.

Objective To investigate the changes in cellular immune function and biochemical indicators of conventional submarine crew both before and after prolonged deployment at sea.Methods Sixtytwo submariners were recruited as the subjects of our study.Detections were made on T lymphocyte subpopulation and NK cell (CD3 + , CD4 + , CD8 + , CD4 +/CD8 + and NK cells) , heptorenal function as well as 13 biochemical indicators [blood glucose (Glu), aspartate amninotransferase (AST), alanine aminotransferase (ALT), AST/ALT, UREA, creatinine (CREA), potassium (K), sodium (Na) and chlorine (Cl), calcium (Ca), magnesium (Mg), phosphorus (P) and iron (Fe)].Results As compared with those before prolonged deployment at sea, CD3 + levels in the T lymphocyte subpopulation after prolonged deployment at sea (67.02％ ± 7.30％ and 68.91％ ± 8.15％ respectively) , CD4 + levels(33.59％ ± 5.61％ and 36.87％ ± 3.65 ％ respectively) , and CD4 +/CD8 + levels (1.22 ± 0.45, 1.46 ± 0.52 respectively) , were all significantly increased (P ＜-0.05).However, CD8 + levels were obviously decreased(27.32％ ± 8.21％ ,25.25％ ± 4.38％) (P ＜ 0.05).Blood glucose levels were obviously increased [(3.68 ± 0.85) mmol/L and (4.38 ± 1.15) mmol/L respectively] (P ＜ 0.05).Ca levels were also elevated [(2.48 ± 0.11) mmol/L and (2.54 ± 0.12) mmol/L respectively] (P ＜ 0.05).Na levels were respectively [(141.08 ± 5.75) mmol/L,(138.08 ± 2.86)mmol/L] , C1 levels were obviously decreased, which were respectively [(103.12 ± 3.09)mmol/L and(98.89 ±4.28)mmol/L] (P ＜0.01), and Fe levels were also obviously decreased, which were [(23.14 ± 6.75) μmol/L and (21.54 ± 7.34) μmol/L] respectively (P ＜ 0.05).Though biochemical indicators of heptorenal function were elevated to various extents, no statistical differences could be noticed (P ＞ 0.05).Conclusions The immune response of the conventional submariners during this prolonged deployment at sea was enhanced, the blood glucose and Ca levels were elevated, but Fe, Na and Cl levels were decreased, indicating that nutritional components should be adjusted in future submarine deployments at sea,and attention should be paid to the changes in blood glucose, so as to ensure the mental health of the submariners.