Effects of Different Tidal Volumes and PEEPs on Cardiac Output in Pigs Measured by Pulmonary Artery Catheter， Pulse Contour Analysis and Transpulmonary Thermodilution / 中山大学学报(医学科学版)

ObjectiveTo compare the effects of different tidal volumes and positive end expiratory pressures （PEEPs） during mechanical ventilation on the cardiac output of pigs measured by pulmonary artery catheter， transpulmonary thermodilution and pulse contour analysis， and to explore their consistency in cardiac output determination. MethodsTwelve experimental pigs were selected and randomly divided into 3 groups， with 4 pigs in each. Cardiac output was measured by different methods， control group by pulmonary artery catheter， group A by transpulmonary thermodilution and group B by pulse contour analysis. Then we compared the effects of different tidal volumes and PEEPs on the cardiac output of pigs and to explore the consistency. The correlation coefficient between pulse contour analysis and pulmonary artery catheter was r=0.754， and they were positively correlated. The correlation coefficient between transpulmonary thermodilution and pulmonary artery catheter was r=0.771， and they were positively correlated. In determining cardiac output， pulse contour analysis was consistent with pulmonary artery catheter， with a relative error of 13.5% between them； transpulmonary thermodilution was consistent with pulmonary artery catheter， with a relative error of 12.9% between them. The cardiac output decreased significantly along with the increase of tidal volumes or PEEPs and the differences were statistically significant （P<0.05） ConclusionPulmonary artery catheter， transpulmonary thermodilution and pulse contour analysis are well consistent with each other in measuring the cardiac output of pigs. The pigs’cardiac output gradually decreased along with the increase of tidal volumes or PEEPs during mechanical ventilation.

Preparation and Identification of High Immunogenic A/PR/8/34 Maternal Strain HA Protein for Influenza Virus Classical Reassortment / 病毒学报

Preparation of maternal strain A/PR/8/34 HA antiserum for influenza virus classical reassortment. A/PR/8/34 virus was digested by bromelain after inactivation and purification. 5%-20% sucrose continuous density gradient centrifugation method was used to purify HA protein. SIRD method was used to select the target protein. SDS-PAGE method was used to identified HA protein. High Immunogenic A/PR/8/34 HA protein was successfully prepared and HI titer reached 10240. High purity HA antiserum was identified by SIRD method. The key reagent in the classical reassortment of influenza virus was prepared, and the complete set of technical methods were explored, which laid the foundation for the independent research and development of seasonal influenza vaccine strains of China.

Prognosis impact of lymph nodes metastasis in pancreatic cancer / 中国医师进修杂志

Objective To explore the prognosis impact of lymph nodes metastasis in pancreatic cancer.Methods The clinical data of 61 patients with pancreatic cancer who underwent pancreaticoduodenectomy from January 2004 to September 2011 were analyzed retrospectively.Patients were categorized into different groups by lymph nodes metastasis status,count of positive lymph nodes,location of positive lymph nodes,lymph nodes ratio (LNR) and other factors.Kaplan-Meier,log-rank and COX proportional hazard models were used to evaluate the prognostic effect.Results Median survival for the overall 61 patients was 13 months (95％ CI 9.158-16.842),with 6 months,1 year,3 years,5 years survival rates of 84.6％,47.7％,14.3％ and 9.1％ respectively.Univariate analysis showed:the median survival of patients with and without lymph nodes metastasis had statistical significant outcome (P ＜ 0.01).Patients within the first station lymph nodes metastasis had a better outcome than those lymph nodes metastasis beyond the first station (P ＜0.05).Patients with LNR ≤0.2 had better prognosis than those LNR ＞ 0.2 (P ＜ 0.01).The number of lymph nodes examined had no effect on overall survival in either nodes-positive patients or nodes-negative patients (P ＞ 0.05).The count of positive lymph nodes did not affect the prognosis in the pN1 patients (P＞ 0.05).Multivariate analysis showed:location of positive lymph nodes and LNR were independent predictors of the prognosis in the pN1 patients.Conclusions Lymph nodes metastasis status has significant effect on the prognosis of the pancreatic cancer.Location of positive lymph nodes and LNR are independent predictors of the prognosis in the pN1 patients.The number of lymph nodes examined and the number of positive lymph nodes have no effect on the prognosis of the pancreatic cancer.