AIM To assess the diagnostic value of a laparoscopic finding of a hepatic subcapsular spider-like telangiectasis (HSST) sign in biliary atresia. METHODS A retrospective study was conducted first and then a validation ...AIM To assess the diagnostic value of a laparoscopic finding of a hepatic subcapsular spider-like telangiectasis (HSST) sign in biliary atresia. METHODS A retrospective study was conducted first and then a validation set was used to investigate the value of an HSST sign in predicting biliary atresia (BA). In the retrospective study, laparoscopic images of the liver surface were reviewed in 126 patients with infantile cholestasis (72 BA patients and 54 non-BA cholestasis patients) and a control group of 38 patients with nonhepatic conditions. Analysis was first made by two observers separately and finally, a consensus conclusion was achieved. Then, the diagnostic value of the HSST sign was validated in an independent cohort including 45 BA and 45 non-BA patients. RESULTS In the retrospective investigation, an ampli.ed HSST sign was found in all BA patients, while we were unable to detect the HSST sign in 98.1% of the 54 non-BA patients. There was no HSST sign in any of the control subjects. In the first review, the sensitivity and specificity from one reviewer were 100% and 98.1%, respectively, and the results from the other reviewer were both 100%. The consensus sensitivity and specificity were 100% and 98.1%, respectively. The HSST sign was defined as being composed of several enlarged tortuous spider-like vascular plexuses with two to eight branches distributed on all over the liver surface, which presented as either a concentrated type or a dispersed type. In the independent validation group, the sensitivity, specificity, positive predictive value and negative predictive value of the HSST sign were 100%, 97.8%, 97.8% and 100%, respectively. CONCLUSION The HSST sign is characteristic in BA, and laparoscopic exploration for the HSST sign is valuable in the diagnosis of BA.展开更多
In rolling experiments,the performances of spider-like robot are limited greatly by its motors’driving ability;meanwhile,the ground reaction forces are so great that they damaged the rods.In this paper,we solve above...In rolling experiments,the performances of spider-like robot are limited greatly by its motors’driving ability;meanwhile,the ground reaction forces are so great that they damaged the rods.In this paper,we solve above problems both mechanically and by control.Firstly,we design the parameters of the central pattern generator(CPG)network based on the kinematics of the robot to enable a smooth rolling trajectory.And we also analyze the kinematic rolling and dynamic rolling briefly.Secondly,we add torsion springs to the passive joints of the spider-like robot aiming to make use of its energy storage capacity to compensate the insufficient torque.The simulation results show that the optimized CPG control parameters can reduce the fluctuation of the mass center and the ground reaction forces.The torsion spring can reduce the peak torque requirements of the actuated joints by 50%.展开更多
基金Supported by the Public Welfare Research Special Fund of the National Health and Family Planning of China,No.201402007
文摘AIM To assess the diagnostic value of a laparoscopic finding of a hepatic subcapsular spider-like telangiectasis (HSST) sign in biliary atresia. METHODS A retrospective study was conducted first and then a validation set was used to investigate the value of an HSST sign in predicting biliary atresia (BA). In the retrospective study, laparoscopic images of the liver surface were reviewed in 126 patients with infantile cholestasis (72 BA patients and 54 non-BA cholestasis patients) and a control group of 38 patients with nonhepatic conditions. Analysis was first made by two observers separately and finally, a consensus conclusion was achieved. Then, the diagnostic value of the HSST sign was validated in an independent cohort including 45 BA and 45 non-BA patients. RESULTS In the retrospective investigation, an ampli.ed HSST sign was found in all BA patients, while we were unable to detect the HSST sign in 98.1% of the 54 non-BA patients. There was no HSST sign in any of the control subjects. In the first review, the sensitivity and specificity from one reviewer were 100% and 98.1%, respectively, and the results from the other reviewer were both 100%. The consensus sensitivity and specificity were 100% and 98.1%, respectively. The HSST sign was defined as being composed of several enlarged tortuous spider-like vascular plexuses with two to eight branches distributed on all over the liver surface, which presented as either a concentrated type or a dispersed type. In the independent validation group, the sensitivity, specificity, positive predictive value and negative predictive value of the HSST sign were 100%, 97.8%, 97.8% and 100%, respectively. CONCLUSION The HSST sign is characteristic in BA, and laparoscopic exploration for the HSST sign is valuable in the diagnosis of BA.
基金the Fundamental Research Funds for the Central Universities of China(No.M15JB00250)。
文摘In rolling experiments,the performances of spider-like robot are limited greatly by its motors’driving ability;meanwhile,the ground reaction forces are so great that they damaged the rods.In this paper,we solve above problems both mechanically and by control.Firstly,we design the parameters of the central pattern generator(CPG)network based on the kinematics of the robot to enable a smooth rolling trajectory.And we also analyze the kinematic rolling and dynamic rolling briefly.Secondly,we add torsion springs to the passive joints of the spider-like robot aiming to make use of its energy storage capacity to compensate the insufficient torque.The simulation results show that the optimized CPG control parameters can reduce the fluctuation of the mass center and the ground reaction forces.The torsion spring can reduce the peak torque requirements of the actuated joints by 50%.
