To investigate the morphological properties of pig cerebral bridging vein. Methods. The morphology and fibre arrangement of 15 cerebral bridging veins obtained from 7 Danish Yorkshire landrace pigs were observed. Resu...To investigate the morphological properties of pig cerebral bridging vein. Methods. The morphology and fibre arrangement of 15 cerebral bridging veins obtained from 7 Danish Yorkshire landrace pigs were observed. Results. There was a narrow region at the junction of the cerebral bridging veins and superior sagittal sinus termed“ outflow cuff segment". The diameter and length of outflow cuff segment were much smaller and the thickness was higher than those of the cerebral bridging veins (P0.05). Conclusions. There were differences in fibre arrangement and morphological properties between the outflow cuff segment and the cerebral bridging vein, just like a resistance valve, the outflow cuff segment may play an important role in stabilizing cerebral venous outflow and regulating intracranial pressure.展开更多
AIM: To measure the time-dependent (viscoelastic) behavior in the change of the small intestinal opening angle and to test how well the behavior could be described by the Kelvin model for a standard linear solid. M...AIM: To measure the time-dependent (viscoelastic) behavior in the change of the small intestinal opening angle and to test how well the behavior could be described by the Kelvin model for a standard linear solid. METHODS: Segments from the duodenum, jejunum, and ileum were harvested from 10 female Wistar rats and the luminal diameter, wall thickness, and opening angle over time (θ(t)) were measured from rings cut from these segments. RESULTS: Morphometric variations were found along the small intestine with an increase in luminal area and a decrease in wall thickness from the duodenum to the ileum. The opening angle obtained after 60 rain was highest in the duodenum (220.8±12.9°)and decreased along the length of the intestine to 143.9±8.9° in the jejunum and 151.4±9.4° in the ileum. The change of opening angle as a function of time, fitted well to the Kelvin model using the equation θ(t)/θo = [1-ηexp (-λt)] after the ring was cut. The computed creep rate λ. did not differ between the segments. Compared to constant calculated from pig aorta and coronary artery, it showed that α agreed well (within 5%), η was three times larger than that for vascular tissue, and λ ranged ±40% from the value of the pig coronary artery and was a third of the value of pig aorta. CONCLUSION: The change of opening angle over time for all the small intestine segments fits well to the standard linear spring-dashpot model. This viscoelastic constant of the rat small intestine is fairly homogenous along its length. The data obtained from this study add to a base set of biomechanical data on the small intestine and provide a reference state for comparison to other tissues,diseased intestinal tissue or intestinal tissue exposed to drugs or chemicals.展开更多
Nowadays, mixed liver tumors are more frequently diagnosed due to better imaging, advanced immunohistochemistry (IHC) staining techniques and better knowledge of hepatic tumorigene- sis [1–3] . Such tumors represent ...Nowadays, mixed liver tumors are more frequently diagnosed due to better imaging, advanced immunohistochemistry (IHC) staining techniques and better knowledge of hepatic tumorigene- sis [1–3] . Such tumors represent a mosaic of components with dis- tinct histogenesis and carcinogenic pathways. As their occurrence in the liver is very rare, their behavior and natural history are difficult to determine, and their management remains empirical. An uncommon case of a composite tumor harboring hepatocellular carcinoma (HCC) and hepatic hemangiosarcoma (HHS) components in a liver transplant (LT) recipient is reported herein.展开更多
文摘To investigate the morphological properties of pig cerebral bridging vein. Methods. The morphology and fibre arrangement of 15 cerebral bridging veins obtained from 7 Danish Yorkshire landrace pigs were observed. Results. There was a narrow region at the junction of the cerebral bridging veins and superior sagittal sinus termed“ outflow cuff segment". The diameter and length of outflow cuff segment were much smaller and the thickness was higher than those of the cerebral bridging veins (P0.05). Conclusions. There were differences in fibre arrangement and morphological properties between the outflow cuff segment and the cerebral bridging vein, just like a resistance valve, the outflow cuff segment may play an important role in stabilizing cerebral venous outflow and regulating intracranial pressure.
基金Supported by the Karen Elise Jensens Foundation and the Danish Technical Research Council
文摘AIM: To measure the time-dependent (viscoelastic) behavior in the change of the small intestinal opening angle and to test how well the behavior could be described by the Kelvin model for a standard linear solid. METHODS: Segments from the duodenum, jejunum, and ileum were harvested from 10 female Wistar rats and the luminal diameter, wall thickness, and opening angle over time (θ(t)) were measured from rings cut from these segments. RESULTS: Morphometric variations were found along the small intestine with an increase in luminal area and a decrease in wall thickness from the duodenum to the ileum. The opening angle obtained after 60 rain was highest in the duodenum (220.8±12.9°)and decreased along the length of the intestine to 143.9±8.9° in the jejunum and 151.4±9.4° in the ileum. The change of opening angle as a function of time, fitted well to the Kelvin model using the equation θ(t)/θo = [1-ηexp (-λt)] after the ring was cut. The computed creep rate λ. did not differ between the segments. Compared to constant calculated from pig aorta and coronary artery, it showed that α agreed well (within 5%), η was three times larger than that for vascular tissue, and λ ranged ±40% from the value of the pig coronary artery and was a third of the value of pig aorta. CONCLUSION: The change of opening angle over time for all the small intestine segments fits well to the standard linear spring-dashpot model. This viscoelastic constant of the rat small intestine is fairly homogenous along its length. The data obtained from this study add to a base set of biomechanical data on the small intestine and provide a reference state for comparison to other tissues,diseased intestinal tissue or intestinal tissue exposed to drugs or chemicals.
文摘Nowadays, mixed liver tumors are more frequently diagnosed due to better imaging, advanced immunohistochemistry (IHC) staining techniques and better knowledge of hepatic tumorigene- sis [1–3] . Such tumors represent a mosaic of components with dis- tinct histogenesis and carcinogenic pathways. As their occurrence in the liver is very rare, their behavior and natural history are difficult to determine, and their management remains empirical. An uncommon case of a composite tumor harboring hepatocellular carcinoma (HCC) and hepatic hemangiosarcoma (HHS) components in a liver transplant (LT) recipient is reported herein.