Recent studies of immunology have aroused new interest in regulatory T cell for immune responses,and scientists have recognized that suppressor T cells exist in vivo and regulatory T(Treg) cells play a crucial role in mediating immune tolerance and preventing autoimmune diseases.This article reviews the types,characteristics,mechanisms,and roles of Treg in immune tolerance,aiming to offer some important theoretical evidence for the treatment of allograft rejection and autoimmune diseases.

Objective To develop the numerical method for the steady and unsteady wet steam condensing flow in turbine stage. Methods An Eulerian/Eulerian numerical model is used to describe the spontaneous condensation flow in the steam turbine. For the steady condensing flow computations, the mixing plane model was used. For the unsteady condensing flow computations, the sliding mesh method was used to simulate the rotor-stator interactions. Results The numerical results showed the obvious differences between non-condensing and condensing flows. The results also showed the unsteadiness effect due to rotor-stator interactions had a deep influence on the formation and growth process of water droplets. Conclusion The numerical methods presented in this paper are valid for the condensing flow in the turbine stage.

171.1?mol/L) was 25.0%, 37.7% and 46.3%, the percentage of the fulminating hepatitis was 3.0%, 5.9% and 14.0%, and the mean hospital stay days for the convalescent patients were 31.59?18.97, 31.13?13.70 and 37.51?18.33 days, respectively. All these variables were significantly higher in aged group compared with youth and middle-aged groups. The levels of alanine transaminase (ALT) lowered significantly with the advance of age, and they were 1 711.7?1 063.4, 1 423.0?913.2 and 1 162.7?792.5U/L, respectively. The same was true in serum albumin and choline esterase (ChE). On the other hand, the percentage of acute hepatitis without jaundice decreased to 17.9%, 6.4%and 2.5% from the youth to the aged. However, TBIL on admission (131.41?106.97 vs 169.60?136.11 vs 164.36?106.22?mol/L) and the elevation of the peak of TBIL (135.01?109.15 vs 186.08?150.64 vs 209.63?143.74?mol/L) of the middle-aged and the aged were significantly higher than those of the youth. There was no significant difference in the symptoms, the ratio of direct to total bilirubin, mortality to complications among them. Furthermore, the serum IgM and IgG antibodies against HEV were negative in about 8.1% of the patients with HEV. Conclusion With a higher incidence and more severe hepatic damage, the middle-aged and the aged patients need a longer duration for recovery than the young patients.

Objective To summarize clinical experience of emergent surgery for severe liver trauma with rupture of major blood vessels. Methods The clinical data of 12 cases suffering from severe liver trauma with rupture of perihepatic and intrahepatic large blood vessels were retrospectively analyzed. These cases were from Dec 2000 to May 2008. All the cases underwent emergency operation, 6 cases were treated with liver lobectomy: among those 1 case with right posterior lobe liver resection, 1 case with irregular right lobe liver resection, 3 cases with left hemihepatectomy, and 1 case with left lateral lobectomy. Seven cases with rupture of major blood vessels were treated by repair or ligature and/or packing including repair of posthepatic inferior vena though the middle fissure in 2 cases, and through retrahepatic space in one case, interrupted suture of the portal vein in 2 cases, interrupted suture of the right hepatic veins in 2 cases. Mattress suture was applied to the ruptured hepatic veins in 7 cases including mattress suture of the branch of right hepatic vein and middle hepatic vein in 1 case, mattress suture of right hepatic vein in 1 case, suture of middle hepatic vein in 2 cases, and suture of left hepatic vein in 3 cases. One case was treated with ligation of hepatic artery and 3 cases with gauzes packing. Results Among all the 12 cases, 9 cases were cured, 3 cases died: two were caused by severe trauma together with hemorrhagic shock, one by sever brain injury together with hemorrhagic shock. Conclusions Prompt operation, precise stop bleeding and correct operation style are the key for successful rescue of patients suffering from severe liver trauma and massive bleeding.

Objective To analyze characteristics of severe liver trauma and efficacy of different surgical procedures. Methods Clinical data of 109 patients with severe liver trauma treated in the recent 10 years were retrospectively analyzed. Debriding suture was performed in 32 patients, gauze tamponade in 5, debridement hepatectomy in 59 and anatomical hepatectomy in 13 patients. Results In all the 109 patients, 92 were cured and 17 died. The dead patients included 3 with grade Ⅲ trauma,9 with grade Ⅳ trauma, and 5 with grade V trauma. Among the dead patients, there were 3 patients with simple liver injury (17.6%) and 14 with associated injury (82.4%). Conclusion Right hepatic serious damage is the main type of severe liver trauma and is always complicated with associated injury and needs emergency treatment. Application of the most appropriate surgical approach according to the traumatic condition is important to promote the successful rate of treatment.

Objective　To investigate the changes of free calcium distribution in hepatocytes after administration of phenylephedrine. Methods The changes of fluorescence intensity were observed by confocal laser scanning microscopy after administration of phenylephedrine alone or pretreated with phentolamine before phenylephedrine administration. Results　The fluorescence intensity increased rapidly after administration of phenylephedrine to hepatocytes. When liver cells were pretreated by phentolamine before phenylephedrine administration, the changes of fluorescence intensity not obvious. Meanwhile, the inconformity of the fluorescence intensity in hepatocytes suggested the existence of the second subarea of free calcium distribution. Conclusion　Ca2+ signal can be arisen by phenylephedrine via the α-receptor in hepatocytes in vitro. The distribution and dynamic changes of free calcium in hepatocytes display some characteristics.

Xanthone and its derivatives occupy a large part of the family of natural polyphenolic compounds with various biological and pharmacological activities.In recent years (from 2006 to 2011),it was reported that 127 xanthones were discovered from plants and fungi using various modem separation methods including silica gel/polyamide column chromatography,HPLC,high-speed counter-current chromatography,high-performance centrifugal partition chromatography,etc.Since total synthesis and structure modification for xanthone and its derivatives have been given attention worldwide,we introduced the synthetic methods of xanthone skeletons as well.Unfortunately,to date,there are still weaknesses in current methods of separation and synthesis,which need to be improved.This review,to a certain extent,provides necessary foundation for the further research and development of medicines containing xanthone and its derivatives.

Objective Corneal alkali burn is a major cause of corneal neovascularization ( CNV) .Confocal microscopy was used to observe the therapeutic effects of KH902 eye drops for the treatment of corneal alkali burns. Methods 24 adult rabbits were randomly divided into two groups( n=12) , alkali burn model being established:experimental group by KH902 eye drops and control group by saline solution 3 times a day.Confocal microscopy was given at 3, 7, 14, 28 d post-operatively (po). Results Corneal epithelium deletion or vacuolar necrosis was found at 3 d po, along with stromal edema.There was no obvious inflammatory cell or no immunocyte infiltration.No difference was found in the corneal structures between two groups.CNV appeared in the peripheral stroma in both groups at 7d po.Inflammatory cell infiltration was more severe in the limbus and peripheral sections in control group than in control group.At 14 d po, inflammatory cells declined gradually and CNV took shape.At 28 d po, scarring and decreased inflammatory cells were found in both groups, while the experimental group had fe-wer and smaller blood vessels than the control group.As to the area of CNV, it was respectively (35.42 ±6.40) mm2, (60.23 ±5.35) mm2, (60.23 ±5.35)mm2 at 7, 14, 28d po in control group, statis-tical difference being found among different time points(P<0.05).While in experiment group, the area of CNV was respectively (22.11 ±5.45)mm2, (31.62 ±7.19)mm2, (28.54 ±3.01) mm2at 7, 14, 28 d po without statistical difference.(P>0.05).The CNV area in experiment group is significantly less than that in the control group at 14 d and 30 d po(P<0.05).The inflammatory cell density in control group was respectively (74.21 ±9.33)mm2, (1883.39 ±43.11)mm2, (2532.10 ±98.00)mm2, (723.05 ± 23.34)mm2at 3,7, 14, 28 d po, and (58.0 ±10.22)mm2, (656.90 ±33.01)mm2, (432.32 ±60.11)mm2, (122.11 ±30.37) mm2respectively at 3,7, 14, 28d po in experiment group, significant difference was found at different time points in both groups(P<0.05), among which significant decreased inflammatory cells was found in experiment group compared with control group (P<0.05). Conclusion KH902 eye drops can be used for the inhibition of CNV and inflammatory cell infiltration after alkali burn.

Objective　To establish the animal model of denervation of sympathetic nerve and to explore the effects of denervation of the sympathetic nerve on liver regeneration after partial resection. Methods　The animal model of denervation of sympathetic nerve was made with 6-OHDA. A total of thirty male Wistar rats were divided equally into experimental and control group. The left and middle lobe of liver were resected with improved Higgins and Anderson's method. Meanwhile, denervation was made in the experimental group. All the rats were killed by haemospasia on the 7 th day after operation. HMI, RLR and MI were measured. The rates of DNA synthesis were detected by 3H-TdR method. Results　The concentration of NE decreased extremely on day 3 to day 14 after administration of 6-ONDA. No death happened in all the rats 7 days after liver resection. HMI, RLR, MI and 3H-TdR incorporation significantly decreased in experimental group compared with that in control (P<0.01). Conclusion　The chemical denervation of sympathetic nerve can be aroused by administration of 6-OHDA. Regeneration of the liver is inhibited by the denervation of sympathetic nerves.

Objective To explore the CT and MRI findings of Kimura disease in different location.Methods The CT and MRI obtained in 19 patients with histologically proved Kimura disease were reviewed retrospectively.Results Of these 19 patients with Kimura disease, the head and neck was involved in 16 patients, other locations less commonly involved were the lung(n=1),chest wall(n=1),liver and spleen(n=1).Kimura disease of head and neck,the density abnormal appeared as nodular,mass or diffuse on CT imaging, the CT value of lesion was similar to muscle, MRI manifested as a slightly hypo-or isointense lesion on T1WI and hyperintense on T2WI,most of the lesions demonstrated moderate or marked enhancement on postcontrast CT and MR images.Kimura disease of lung and chest wall,lesion appeared as a solid mass on imaging, there was moderate enhancement in the lung lesion and rim enhancement in the chest wall lesion.Kimura disease of liver and spleen: lesion showed nodular, mild and gradual upward enhancement.Conclusion Imaging findings of Kimura disease are not characteristic, it is very essential to know the lesion combined with the laboratory and pathologic features.