Objective To investigate the CT,MRI features and differential diagnosis of central nervous system primitive neuroec-todermal tumors (cPNET).Methods The CT and MRI findings of 1 5 cases with cPNET proved by pathology were analyzed retro-spectively,and we summarized the imaging features and differential diagnosis.Results For this group,the average age was (8.82± 2.53)and the male to female ratio was 9 ︰6.All lesions located in supratentorial region,which had relatively large volume (average diameter of 6.3 cm),cystic necrosis (12/15),and no or mild peritumoral edema.cPNET showed isodensity,slight hyperdensity or slight hypodensity on CT plain scan,and demonstrated uniform or inhomogeneous enhancement.On MRI plain scan,solid part showed isointensity or slight hypointensity signal on T1 WI,isointensity or slight hyperintensity signal on T2 WI,hyperintensity sig-nal on DWI(12/15),isointensity(9/15)or slightly hyperintensity signal on FLAIR,and showed obvious uniform,honeycombed or irregular enhancement after enhanced scan,no enhancement in cystic necrosis.Conclusion cPNET have certain characteristics,inclu-ding the lower onset age,relatively large volume with well-defined edge and no or mild peritumoral edema,hyperintensity signal on DWI,isointensity signal on FLAIR.

Objective To investigate thickness of the hilar periportal space and caudate-right lobe ratio in the patients with chro-nic hepatitis B and liver cirrhosis after hepatitis B .Methods Eighty-four patients who were clinically and histologically diagnosed with chronic hepatitis B or cirrhosis and 18 healthy subjects without history of liver disease underwent abdominal MRI .The rela-tionship among liver fibrosis degree ,hilar periportal space and caudate-right lobe ratio were observed .Results There was signifi-cant correlation between the hilar periportal space and hepatic fibrosis for chronic hepatitis and cirrhosis (rs = 0 .546 ,P< 0 .01) . There was significant difference between S2 and S3 for thicknesses of the hilar periportal space(P<0 .01) ,and no significant differ-ence among S3 ,S4 and cirrhosis(P=0 .188) .A cutoff value of 9 mm for the hilar periportal space had a sensitivity of 85 .37% and a specificity of 76 .79% for a diagnosis of hepatic fibrosis with S3 or higher .There was no significant correlation between the caudate-right lobe ratio and hepatic fibrosis(rs = -0 .155 ,P=0 .119) .Conclusion Thicknesses of the hilar periportal space increase gradu-ally with hepatic fibrosis in patients with chronic hepatitis B and cirrhosis ,with a high sensitivity and specificity for a diagnosis of hepatic fibrosis with S3 or higher .

Objective To investigate the chemical constituents in the stems and leaves of Arachis hypogaea.Methods The isolated compounds Ⅰ—Ⅳ were obtained by the combination of silica gel,ODS-18,and Sephadex LH-20 column chromatographies.Structural elucidation was conducted by the moedrn spectral method.Results Seventeen compounds were isolated and identified from the water extraction,and there were four norsesquiterpene compounds from butanol extraction.They are arachiside A(Ⅰ),cucubalactone(Ⅱ),roseoside(Ⅲ),and citroside A(Ⅳ).Conclusion Compound Ⅰ is a new compound named arachiside A and compounds Ⅱ—Ⅳ are isolated from the plants of Arachis Linn.for the first time.

Purpose To investigate the features of 64-slice spiral computerized tomography (CT) on collateral circulation of pancreatic portal hypertension (PPH).Material and Methods the abdominal CT images of 52 patients with PPH confirmed by pathology the Affiliated Hospital of Southwest Medical University from August 2013 to May 2015 were analyzed retrospectively.The collateral circulations of portal vein were recorded.Results There were 21 (40.4％) patients with isolated splenic vein occlusion (ISVO),and 32 (59.6％) patients with non isolated splenic vein occlusion (NISVO) in the total 52 patients.There was no significant difference in the occurrence rate between ISVO and NISVO (x2=1.92,P＞0.05).The main collateral pathways of PPH were pathway Type Ⅰ (28 patients)and pathway Type Ⅲ (22 patients),and 2 patients belonged to pathway Type Ⅱ.The patients in pathway Type Ⅰ or Ⅲ were significantly more than patients in pathway Type Ⅱ(P＜0.01).There were 92.3％ (48/52) of patients with gastroepiploic varicosity,which is significantly higher than other varicose veins (P＜0.001).The significant difference was found between the patients (21.2％) with gastric fundus varicosity and the patients (1.9％)with inferior segment esophageal varices (x2=9.42,P＜0.01).The patients with gastric fundus varicosity and right superior colic varicosity in NISVO were more than those in ISVO (x2=4.15,7.44,P＜0.05).Conclusion For PPH patients,the valuable features of collateral circulation can be revealed by multi-slices CT.

Objective To evaluate early dynamic contrast enhancement CT on multiple organ failure in acute pancreatitis.Methods 333 cases of acute pancreatitis identified by clinical and early dynamic contrast enhancement CT were collected.Patients were divided into organ failure group(OF group,124 cases) and non-organ failure group (notn-OF group,209 cases).All variables including duration of hospitalization,need for intensive care unit,infection,need for operation,mortality and MCTSI,EPIC score were analyzed by U test and x2 test firstly.The variables with significance (P＜0.05) were analyzed by Stepwise Logistic regression further.Results On U test and x2 test,there were significant differences(P＜0.001) between two groups in duration of hospitalization,need for intensive care unit,infection,need for operation,mortality,MCTSI score and EPIC score and APFC + ANC＞ 100 mL,and bilateral pleural effusion/ pulmonary atelectasis.The Stepwise Logistic regression analysis demonstrated that increased MCTSI and EPIC score,APFC+ANC＞ 100 mL and bilateral pleural effusion/pulmonary atelectasis were 4 independent risk factors of multiple organ failure in acute pancreatitis.Conclusion Multiple organ failure in acute pancreatitis can be judged with early dynamic contrast enhancement CT for improved treatment.