Objective To study the value of three-dimensional (3D) visualization and virtual surgery system in piggyback liver transplantation. Methods Two patients who suffered from choledocholithiasis were scanned by 64-slice spiral CT and the data were collected. The segmentation of the hepatic CT images was carried out. The 3D model of the liver and the intrahepatic vessels was reconstructed, and was imported to the FreeForm Modeling System in STL format for smoothing and modifying. Piggyback liver transplantation was simulated with the force-feedback equipment (PHANToM). Results The reconstructed 3D model of the liver was vivid, and the process of the virtual piggyback liver transplantation was verisimilar. Conclusions The 3D model of the liver enables the simulation of piggyback liver transplantation. It can reduce the risk and complications of the surgery, and enhance the communication between doctor and patient through designing surgical plan and demonstrating visualized operation before surgery. Virtual liver transplantation is also helpful during the training of medical workers.

Objective To examine the association between social isolation and cognitive function among the elderly living in the communities of Daqing city.Methods A total of 981 community residents aged 60 years or over,were surveyed with a questionnaire.Both Lubben Social Network Scale-6 (LSNS-6) and Montreal Congnitive Assessment (MoCA) Changsha Versions were used to respectively screen the status of social isolation and cognitive function,on these elderly.Results The average age was 71 years old for the 981 study participants.10.60％ (104/981) of the participants were assessed as having the status of social isolation,9.48％ (93/981) as having marginal family ties and 13.97％ (137/981) as having marginal friendship ties.Results from the multivariate linear regression analysis revealed that participants with higher scores of LSNS-6 presenting better cognitive function score,with a partial regression coefficient as 0.10 (P＜0.01).The MoCA scores in participants with social isolation (20.38 ± 5.54) were significantly lower than the ones without social isolation (22.10 ± 5.01) and the difference was statistically significant (P＜0.01).Social isolation was significantly related to the domain scores on visuo-spatial constructional executive functions (P=0.02),naming (P=0.03),language (P=0.01) and delayed memory functions (P＜0.01),but not with other domains as concentration (P=0.33),orientation (P=0.27) or abstraction (P=0.49).Conclusion The findings suggested that social isolation was mainly caused by the lack of friendship ties and associated with cognitive function and among the elderly in Daqing city,Heilongjiang province.

OBJECTIVETo understand the positive rates of hepatitis B surface antigen (HBsAg) and surface antibody (anti-HBs) among adults aged ≥18 years in communities in Chaoyang district, Beijing.

METHODSHBsAg and anti-HBs were tested with ELISA reagents for participants in the Community Diagnosis Survey (3 000 person were sampled in each community according to the age and sex distribution of the residents) in all 42 communities in Chaoyang district by Beijing Center for Disease Control and Prevention (CDC) and Chaoyang CDC. The data of 35 communities in which at least 1 000 adults were tested were analyzed.

RESULTSA total of 78 100 adults were tested for HBsAg and anti-HBs in the 35 communities. The crude positive rate of HBsAg was 2.24% (95% CI: 2.13%-2.34%). The highest age-specific HBsAg positive rate was 3.00% (95% CI: 2.56%-3.44%) for those aged 40-44 years and the lowest age-specific HBsAg positive rate was 1.69% (95% CI: 1.29%-2.09%) for those aged 18-24 years, respectively. A obvious difference in community- based HBsAg positive rate was founded with the highest of 10.68% (95% CI: 9.43%-11.94%) and lowest of 0.24% (95% CI: 0.13%-0.38%). HBsAg positive rate was significantly lower in local residents than in participants with household registered in other provinces (1.97% vs. 2.98%, P<0.01), but the sex specific difference in HBsAg positive rate was relatively smaller (2.45% in males and 2.07% in females, P<0.01). The multivariate logistic regression analysis showed that age, community, occupation, residence status and sex were all associated with positive rate of HBsAg (P<0.01). The overall positive rate of anti-HBs was 30.85% (95% CI: 30.53%-31.18%), and the highest was 38.10% in age group 18-24 years (95% CI: 36.58%-39.61%) and the lowest was 28.88% in age group 75- years (95% CI: 27.62%-30.15%), respectively. Up to 67.02% of the subjects were both HBsAg and anti-HBs negative (95% CI: 66.69%-67.35%), and the age specific difference was not significant. But significant differences in anti-HBs positive rate and the negative rate of both HBsAg and anti-HBs were found across communities.

CONCLUSIONThe overall positive rate of HBsAg was at a moderate low level among adults in Chaoyang, but the age specific positive rate was high in the middle-aged and the population specific positive rate was high in participants with household registered in other provinces, therefore, the prevention and control of hepatitis B in Chaoyang should be focused on the middle aged people and participants with household registered in other provinces. The community specific differences in the positive rate of HBsAg and anti-HBs across communities need to be further studied.

Adolescent ; Adult ; Age Distribution ; Aged ; Beijing ; epidemiology ; Enzyme-Linked Immunosorbent Assay ; Family Characteristics ; Female ; Hepatitis B ; blood ; Hepatitis B Antibodies ; blood ; Hepatitis B Surface Antigens ; blood ; Hepatitis B virus ; Humans ; Male ; Middle Aged ; Seroepidemiologic Studies ; Sex Distribution ; Specimen Handling ; Young Adult