ObjectiveTo observe the effect of portal blood flow on rat's liver with prehepatic portal hypertension.MethodsSixty-six male Wistar rats were randomly divided into five groups:partial portal vein transfixation group( A,n =20),hepatic artery transfixation after partial portal veins transfixation group( B,n =20),hepatic artery transfixation group (C,n =10),SO group( D,n =10 ),hepatic artery and partial portal vein transfixation group ( E,n =6 ).The mortality as well as the biochemical examination wereobserved at the 12th week after operation.Then the density of the microvascular in portal area and proliferating cell nuclear antigen expression of intro-hepatic bile duct epithelium were determined by immunohistochemical staining method.The ultra microstructure changes of hepatocytes were observed under transmission electron microscope.Results Biochemical examination,including glutamic-oxa-lacetic transaminase,glutamic-pyruvic transaminase and total protein,showed no significant differences anong all groups (P ＞0.05) at the 12th week after operation.Glutamie-oxalacetic transaminase in group A,in group B,in group C and in group D are (132.69±21.03) U/L,(154.40±28.73) U/L,(125.84±26.60) U/L,(134.02±18.42) U/L; glutamic- pyruvic transaminase in group A,in group B,in group C and in group Dare (39.33±8.62) U/L,(44.84 t9.47)U/L,(40.41±8.04) U/L,(38.47±7.29) U/L.Compared with groups C and D,the mortality rate (group A 20％ ; group B 25％),and the microvascular number in portal area increased obviously in group B and A(P ＜0.05).The proliferating cell nuclear antigen expressions of intra-hepatic bile duct epithelium increased significantly in group B (mean optical density 0.345±0.027 compared with the rest groups mean optical density in group A,in group C and in group D are 0.264 ± 0.015,0.258±0.022,0.249±0.021 ) ( P ＜ 0.01 ) ; fat accumulation in the hepatocytes and mitochondria vacuolization were observed under transmission electron microscopic in group A and group B.ConclusionsThe portohepatic collateral circulation still has its significance in liver blood supply of prehepatio portal hypertensive rat; the epithelium of intra-hepatic bile duct was mildly damaged and the microvascular number in hepatic portal area increased as well as the fat accumulated in hepatocytes of prehepatic portal hypertensive rat; if the hepatic artery blood supply is lost,these changes would become more obviously.

Objective To study the ultrasonic image characteristics of the displaced femoral shaft fracture before and post reduction,and to explore its clinical significance in guiding the closed reduction and intramedullary nail fixation.Methods Ultrasonic imaging features of 21 cases of femoral shaft fractures were observed.Closed reduction was completed under ultrasound monitoring,and the characteristics of ultrasonic imaging after fracture reduction were observed.Fixation of femoral fractures with intramedullary nails after closed reduction was completed.Results On the long axis of the femoral shaft,the ultrasonograms displayed a gap between two hyperechoic bands(step sign).On the cross section,two short arc hyperechoic bands can be seen(double short arc sign).After the completion of closed reduction,the step sign and double short arc sign disappeared.In the front and rear of the femoral shaft,there were 2 echo lines connected to a straight line.The line in front of the femoral parallel to the rear(continuous parallel sign).Continuous parallel sign indicated that reduction was achieved,the intramedullary nail guide pin could be successfully inserted into the femoral shaft,to complete the intramedullary nail fixation.Conclusions Ultrasound imaging shows step sign and double short arc syndrome when femoral shaft fracture displaced.Post fracture reduction,the imaging shows continuous parallel sign.Observing ultrasonic image characteristics of the displaced femoral shaft fracture is effective in assisting closed reduction and intramedullary nailing for femoral shaft fractures.