Objective To observe the dynamic level of platelet activation and to analyze the correlation between platelet activation and systemic inflammatory response syndrome(SIRS)in patients with acute ischemie stroke. Methods　Mean platelet component concentration(MPC)and white blood count(WBC)were serially determined in patients with acute isehemic stroke,and other parameters including initial plasma fibrinogen(FIB)and adenosine diphosphate(ADP)aggregative rate were also determined.All parameters were compared between the SIRS group and the non-SIRS group.Correlation was analyzed between initial MPC and SIRS score,WBC,FIB and ADP aggregative rate. Results MPC level was declined slightly on the first day,and was followed by a relatively low MPC level from the second day to the forty-fifth day.The average level was fluctuated between 229 g/L and 242 g/L.There was no significant difference in initial FIB(t=1.835,P=0.07)between the SIRS group and the non-SIRS group,but the differences of other parameters had statistical significance(all P＜0.01).In the first three days,MPC level was negatively correlated with SIRS score(r=-0.392,-0.376,-0.341,t=3.484,3.405,3.125 respectively,all P＜0.01),but not correlated with WBC,FIB and ADP aggregative rate(P＞0.05). Conclusions　Platelets maintain an activated state during the entire course of ischemic stroke.The initial level of platelet activation.WBC count and ADP aggregative rate are higher in SIRS patients than in non-SIRS patients.The initial level of platelet activation suggests the severity of SIRS,and may be one of the independent risk factors for SIRS.

Objective: To investigate the effect of human chorionic gonadotrophin (hCG) on the gene expression of migration inhibitory factor (MIF) in human peripheral blood mononuclear cell (PBMC). Methods: The healthy human PBMC was cultured with hCG at 37 ℃, 5%CO_2 for 2 hours. The mRNA of harvested cells was isolated. The MIF mRNA was detected by real-time RT-PCR. Results: In a certain range of doses, the mRNA expression of MIF significantly increased following the increase of hCG in a dose depandent manner, and it reached to a peak 1-2 hours after culture, then returned to the minimum level after 8 hours. Conclusion: In a certain range of doses, hCG can increase the mRNA expression of MIF. This effect is correlated with reacting time. It is suggested that hCG may involve in immune response by up-regulating the production of cytokines by PBMC.