Portal biliopathy(PB) is defined as the presence of biliary abnormalities in patients with non-cirrhotic/nonneoplastic extrahepatic portal vein obstruction(EHPVO) and portal cavernoma(PC). The pathogenesis of PB is du...Portal biliopathy(PB) is defined as the presence of biliary abnormalities in patients with non-cirrhotic/nonneoplastic extrahepatic portal vein obstruction(EHPVO) and portal cavernoma(PC). The pathogenesis of PB is due to ab extrinseco compression of bile ducts by PC and/or to ischemic damage secondary to an altered biliary vascularization in EHPVO and PC. Although asymptomatic biliary abnormalities can be frequently seen by magnetic resonance cholangiopancreatography in patients with PC(77%-100%), only a part of these(5%-38%) are symptomatic. Clinical presentation includes jaundice, cholangitis, cholecystitis, abdominal pain, and cholelithiasis. In this subset of patients is required a specific treatment. Different therapeutic approaches aimed to diminish portal hypertension and treat biliary strictures are available. In order to decompress PC, surgical porto-systemic shunt or transjugular intrahepatic porto-systemic shunt can be performed, and treatment on the biliary stenosis includes endoscopic(Endoscopic retrograde cholangiopancreatography with endoscopic sphincterotomy, balloon dilation, stone extraction, stent placement) and surgical(bilioenteric anastomosis, cholecystectomy) approaches. Definitive treatment of PB often requires multiple and combined interventions both on vascular and biliary system. Liver transplantation can be considered in patients with secondary biliary cirrhosis, recurrent cholangitis or unsuccessful control of portal hypertension.展开更多
Visual cryptography is a cryptographic technique which emerges in the information security domain in recent years. Each of the sharing sub-keys may be a stochastic noise image or a significative image with no informat...Visual cryptography is a cryptographic technique which emerges in the information security domain in recent years. Each of the sharing sub-keys may be a stochastic noise image or a significative image with no information on the original key. But a mass of sub-keys have to be saved actually, which faces the problem of inconvenient discrimination and management. This paper presents a visual cryptography scheme based on the digital signature for image discrimination and management, applying the digital signature and the time-stamp technology to the visual cryptography scheme. The scheme both solves the problem on the storage and management of the sharing sub-keys, increases the verification of image contents, thus enhances the validity of storage and management without security effect.展开更多
文摘Portal biliopathy(PB) is defined as the presence of biliary abnormalities in patients with non-cirrhotic/nonneoplastic extrahepatic portal vein obstruction(EHPVO) and portal cavernoma(PC). The pathogenesis of PB is due to ab extrinseco compression of bile ducts by PC and/or to ischemic damage secondary to an altered biliary vascularization in EHPVO and PC. Although asymptomatic biliary abnormalities can be frequently seen by magnetic resonance cholangiopancreatography in patients with PC(77%-100%), only a part of these(5%-38%) are symptomatic. Clinical presentation includes jaundice, cholangitis, cholecystitis, abdominal pain, and cholelithiasis. In this subset of patients is required a specific treatment. Different therapeutic approaches aimed to diminish portal hypertension and treat biliary strictures are available. In order to decompress PC, surgical porto-systemic shunt or transjugular intrahepatic porto-systemic shunt can be performed, and treatment on the biliary stenosis includes endoscopic(Endoscopic retrograde cholangiopancreatography with endoscopic sphincterotomy, balloon dilation, stone extraction, stent placement) and surgical(bilioenteric anastomosis, cholecystectomy) approaches. Definitive treatment of PB often requires multiple and combined interventions both on vascular and biliary system. Liver transplantation can be considered in patients with secondary biliary cirrhosis, recurrent cholangitis or unsuccessful control of portal hypertension.
文摘Visual cryptography is a cryptographic technique which emerges in the information security domain in recent years. Each of the sharing sub-keys may be a stochastic noise image or a significative image with no information on the original key. But a mass of sub-keys have to be saved actually, which faces the problem of inconvenient discrimination and management. This paper presents a visual cryptography scheme based on the digital signature for image discrimination and management, applying the digital signature and the time-stamp technology to the visual cryptography scheme. The scheme both solves the problem on the storage and management of the sharing sub-keys, increases the verification of image contents, thus enhances the validity of storage and management without security effect.
