The Changes of CD4+T Lymphocyte Subsets in Septic Patients

Inclusion Criteria: * Male and female aged 18 years old and over; * Fulfilled at least two criteria of systemic inflammatory response syndrome (a) core temperature higher than 38 °C or lower than 36 °C (b)respiratory rate above 20/min, or PCO2 below 32 mmHg (c) pulse rate above 90/min, and (d) white blood cell count greater than 12,000/μl or lower than \< 4,000/μl or less than 10% of bands. * Clinically suspected infection; Exclusion Criteria: * were under 18 years of age; * were refused by the patients or his/her familiality; * were suffering from acquired immunodeficiency syndrome,virlhepatitis,autoimmune diseases and hematology; * use medicine which can affect immune system,such as Glucocorticoid and Immunosuppressant * died within 24h after being taken into the ICU, or refused to get involved in the study, or gave up treatment during the period of observation