ObjectiveTo investigate the value of the MSCT liver perfusion imaging parameters inthe evaluation of the chronic hepatic fibrosis and cirrhosis. Methods Liver CT perfusion ( CTP ) was performed in 107 participants,including 31 patients with mild hepatic fibrosis( S1,S2),34 patients with severe hepatic fibrosis ( S3,S4 ) and early stage of hepatic cirrhosis which conformed by liver pathologic biopsy,42 patients with hepatic cirrhosis who had typical clinical and image signs,and 30 healthy subjects as control group.The data of CTP ( HAP,PVP,LTP,HPI and TTP) at different stages were obtained with Body perfect CT-syngo CT2007A and control study with histopathologic stage.Compared the study index by the one-way ANOVA analysis. Used Spearman rank correlation to analysis the relationship between liver perfusion imaging parameters and the degrees of the chronic hepatic fibrosis. Used Logistic regression to analysis the maximum.regression coefficient among the liver perfusion imaging paraneters,which affected the histopathologic stage mostly.ResultsIn the subgroups of the chronic hepatic fibrosis S1,S2,S3,S4 to the hepatic cirrhosis,HAP values was (28.9 ±8.6),(24.6 ±2.4),(29.2 ±2.3) and (38.9 ± 7.0) ml · 100 ml -1 · min-1,respectively.HAP decreased firstly,then increased.Statistic analysis showed the difference of HAP between later-stage cirrhosis and other groups( F =40.26,P ＜ 0.01 ).PVP values of above subgroups was (111.3 ± 18.1),(92.9 ±5.3),(73.0 ±9.0) and (54.1 ± 13.8) ml · 100 ml-1 ·min -1,respectively.TLP values of above subgroups was ( 140.2 ± 25.9 ),( 117.1 ± 4.5 ),( 102.3 ± 8.7 )and (93.0 ± 11.8) ml · 100 ml-1.min-1,respectively.The difference of PVP,TL.P among each subgroup was significant ( F =136.79,67.40,respectively,P ＜ 0.01 ).HPI values of above subgroups was (20.4 ± 2.6)％,(21.0 ±2.1)％,(28.5 ±3.1)％ and (42.6± 11.1)％,respectively.TTP values of above subgroups was (123.7±22.2),(137.1 ±27.1),(145.0 ±28.6) and (166.5 ±25.1)s,respectively.The difference of HPI,TTP among each subgroup was significant( F =93.05,17.37,respectively; P ＜0.01 ).PVP,TLP was significant negative correlation with the degree of the hepatic fibrosis( r =-0.920,-0.846,respectively; P ＜0.01 ).HAP,HPI and TTP was significant positive correlation with the degree of the hepatic fibrosis( r =0.611,0.882 and 0.545,respectively; P ＜ 0.01 ).Logistic regression analysis showed the regression coefficient of PVP( - 8.798) was maximum.With an area under the receiver operating characteristic curve of PVP =84.76 ml · 100 ml- 1 · min- 1 as a diagnose critical point.The sensitivity was 0.890,the specificity was 0.950,and the accuracy was 0.931 in the prediction of the chronic hepatic fibrosis.Conclusions MSCT liver perfusion imaging parameters can reflect the hemodynamic changes of chronic hepatic fibrosis and cirrhosis.CTP may be helpful for differentiation the severe hepatic fibrosis and early stage of hepatic cirrhosis and later-stage cirrhosis.

Objective To investigate the value of high-resolution 3.0T MR in the assessment of local infiltration of preoperative rectal cancer.Methods A total of 168 patients pathologically proved rectal cancer underwent both conventional pelvic and rectal high-resolution before operation, and the imaging findings were reviewed retrospectively.The accuracy of preoperative high-resolution 3.0T MR in prediction of pathological staging was assessed,and the characteristic imaging features of local infiltration in preoperative rectal cancer were discussed.Results The relationship between circumference invasion of colorectal cancer and the pathological T staging was moderately positive (rs=0.530,P=0.003).Compared the staging of colorectal cancer on MRI with pathologic T staging,the overall diagnostic accuracy was 84.52%,and there was a stronger correlation between MRI findings and pathological staging (rs=0.837,P=0.001).The best single parameters for diagnosing T3 stage rectal cancer on MRI were nodular convex of the tumor and muscular signal interruption,with 91.1% specificity and 89.7% sensitively respectively.And the best combination of parameters was the cord appearence of intestinal wall and muscular signal interruption,with 89.3% specificity and 78.0% sensitively respectively.Conclusion High-resolution 3.0T MR can be preferable to evaluating local infiltration of rectal cancer, showing a higher clinical value to asseee T staging of preoperative rectal cancer.

Objective To study the methods of differential diagnosis of focal nodular hyperplasia and hepatic adenoma using multiphasic helical CT.Methods The data triphase helical CT of focal nodular hyperplasia (FNH) in 7 cases and hepatic adenomas in 5 cases proved pathologically were aualysed.The number,morphology,size,central scars and calcifications of lesions were observed,and the CT values of lesions and liver parenchyma on plain scan,arterial phase and portal venous phase were measured respectively.Results In 7 cases of FNH , mulitple lesions were present in one case , single lesion was in other 6 cases , totally 10 lesions in which six lesions were larger than 3 cm and four of the other were smaller than 3 cm in diameter , the central scars were detected in 7 cases . Five cases of hepatic adenoma were single and larger than 3 cm in diameter, no central scars were detected . Both focal nodular hyperplasia and hepatic adenoma no calicification could be seen . The study showed no significant difference between mean density values of focal nodular hyperplasia ( 48.18?7.82 ) HU and hepatic adenoma ( 42.54?2.37 ) HU on plain scan . In aterial phase , CT values were significant higher in focal nodular hyperplasia(124.29?18.69) HU than that in hepatic adenoma(83.29?9.09) HU.In the portal venous phase,no significant difference in values were detected between focal nodular hyperplasia(110.51?22.71) HU and hepatic adenoma(123.75?5.01) HU.Conclusion The differential diagnosis of focal nodular hyperplasia and hepatic adenoma can be done by multiphasic helical CT in combination with the quantitative evaluation of the density of liver lesions.

Objective To construct vector expressing soluble mPDL1-hIgGFc and study its effect on the proliferation and apeptosis of cells in vitro. Methods The extrncellular domain of mPDL1 gene was amplified from pmPDL1 vector by PCR and inserted into phIgGFc vector. The recombinant pmPDL1-hIgGFc was transfected into CHO cells by LipofectAMINETM2000, and the transfected cells were named as CHOp. The expression of mPDL1-hIgGFc in the culture supernatants of CHOp was assayed by ELISA and Western blot. The effects of CHOp culture supernatants on mixed lymphocyte culture(MLC) was analysed by Flowm-etry. Results The extracellular domain of mPDL1 gene were obtained from PCR. DNA sequencing and the identification of digestion by HindⅢ and KpnⅠ indicated the recombinant plasmid pmPDL1-hIgGFc was suc-cessfully constructed. ELISA and Western blot analysis proved that the CHOp could express mPDL1-hIgG-Fc. CHOp culture supernatants could inhibit lymphocyte proliferation and induce the apoptosis of the activa-ted T cells in MLC in vitro in a dose-dependent manner. Conclusion The mPDL1-hIgGFc protein could in-hibit lymphocyte proliferation and induce the apoptosis of the activated T cells.