[Objective]To investigate the effect of human umbilical cord mesenchymal stem cells on infected state of human alve?olar type Ⅱ epithelial cells.[Methods]Human alveolar type Ⅱ epithelial cells A549(1×105/mL)2 mL and PA(3×104 CFU/mL)2 mL has grown after 6 hours,add hUCMSC(1 × 106/mL)2 mL as the experimental group,add equal amounts of phosphate buffer (PBS)for infection,A549 and PBS and the medium has grown as the control group. A549 cells morphological changes between the compared groups(Transmission electron microscope,TEM),A549 cell viability(new CCK-8 cell proliferation assay Kit),A549 cells apoptosis(Annexin V-FITC/PI double staining flow cytometry)and the expression of A549 pulmonary surfactant A(SP-A) (Western blot).[Results]Transmission electron microscope cell morphology observation displayed ,infection group A549 cell dam?aged obviously,cell quality appeared empty bubble degeneration,chromatin height agglutination,visible apoptosis bodies;experi?ment group cell package film structure full,nuclear film full,nucleolus obviously,nuclear chromatin electronic density low,chroma? tin uniform,no apoptotic bodies;control group A549 cell structure full,membrane surface micro-fluff rich,nuclear film full,nucle?ar week clearance structure normal,chromatin uniform;infection group and control group compared,Infection group A549 cell sur?vival significantly reduced[(70.35±2.89)% and(97.37±2.07)%,n=3,P<0.01],apoptosis rate significantly increased[(8.63%± 0.16)%and(2.55±0.11)%,n=3,P<0.01],In the infected group,PA could damage A549 cells and decrease the amount of SP-A ex?pression(n=5,P<0.05). In the experiment group,the protective effect of hUCMSC on the A549 cells after infection may increase the expression of SP-A(n=5,P<0.05);[Conclusions]HUCMSC inhibits the infection of A549 cells apoptosis and protection of A549 cells secrete SP-A.

【Objective】To explore the feasibility and simplicity of intelligent automatic registration ultrasound-CT/ MR fusion imaging based on liver surface in localization of focal liver lesions. 【Methods】 Thirty patients with detected focal liver lesions by contrast- enhanced CT or MR were enrolled for ultrasound- CT/MR fusion imaging using the PercuNav fusion imaging system in PHILPS EPIQ7. Both intelligent automatic registration ultrasound- CT/MR fusion imaging based on liver surface（intelligent method）and the conventional internal plane method（manual method）were used for ultrasound-CT/MR fusion imaging. The success rate of registration，the initial registration error and the times of fine-tuning were compared between these two methods.【Results】In all 30 patients，the success rates of registration were both 96.67%（29/30）using intelligent method and manual method. There was no significant difference between these two methods when compared the initial registration error and the times of fine- tuning （P>0.05）. According to the further stratified analysis，in 10 lesions in the left liver，the initial registration error of the manual method was less than that of intelligent method，the difference was statistically significant（P=0.00）. Although the times of fine-tuning of the manual method was less than that of intelligent method，there was no statistically significant difference（P=0.09）；In 20 lesions in the right liver，the initial registration error and the times of fine-tuning of the intelligent method were superior to those of the manual method. The differences were statistically significant （P<0.05）. 【Conclusion】 Intelligent automatic registration ultrasound- CT/MR fusion imaging based on liver surface is a feasible method with high success rate for ultrasound-CT/MR fusion imaging. Compared with the conventional internal plane method，the fusion imaging process is more simple and efficient for the lesions in right liver. It helps to reduce experience dependence of fusion imaging for the operators.