Pagrosomus major larvae were exposed to the water soluble fraction of hydrocarbon in No.0 diesel oil (corresponding to No.2 fuel oil) at concentrations of 0, 0 17, 1.22 and 8 82 mg/L for up to 15 days. Larvae...Pagrosomus major larvae were exposed to the water soluble fraction of hydrocarbon in No.0 diesel oil (corresponding to No.2 fuel oil) at concentrations of 0, 0 17, 1.22 and 8 82 mg/L for up to 15 days. Larvae were sampled on days 9 and l5 of the experiment. Supernatants of viscera tissue extractions were assayed for biochemical response in terms of oxidative stress superoxide dismutase(SOD), activity of selenium dependant glutathione peroxidase(Se GPx) and catalase(Ca), and the concentration of reduced glutathione(GSH). On day 9 of exposure, statistically significant dose related increases in Se GPx and SOD activity, and GSH concentration were observed in all cases except for Se GPx activity under the highest dosage of hydrocarbon. However, on day l5 of exposure, a similar dose related response was only observed for Se GPx activity. GSH concentration decreased and SOD activity showed no statistical difference as compared to controls. However, a significant decrease in compared to day 9 Se GPx activity and GSH concentration, in contrast to increase SOD activity at day 15 as indicates an accelerated accumulation of H 2O 2 and potential oxidative damage under long term exposure of larvae to hydrocarbons. No statistical changes were observed in Ca activity throughout the experiment, possibly owing to the high efficiency of Se GPx. A recovery experiment was performed on indicating that the response of antioxidants measured tending to return to their control levels. These results prove the function of the antioxidant defense system of the larvae to the water soluble fraction of hydrocarbons in No.0 diesel oil.展开更多
Objective: To study the value of multiple MR imaging techniques in the diagnosis of pancreatic carcinoma and the assessment of resectbility of the lesion. Methods: MR imaging was performed in 18 pa-tients with surgica...Objective: To study the value of multiple MR imaging techniques in the diagnosis of pancreatic carcinoma and the assessment of resectbility of the lesion. Methods: MR imaging was performed in 18 pa-tients with surgically and/or pathologically proven pancreatic carcinoma. GRE T1WI, TSE T2WI, GRE T1WI with fat suppression, delayed enhancement GRE T1WI, MRCP and 3D DCE MRA were used in MR scanning. Tumor involvement of the celiac trunk and its main branches, superior mesenteric artery,the portal, splenic and superior mesenteric veins were prospectively graded on a 0-4 scale based on cir-cumferential contiguity of tumor to vessel. Results: On GRE T1WI and TSE T2WI all the lesions showed slightly hypointense and hyperintense, respectively; On GRE T1WI with fat suppression, all the tumors obviously appeared hypointense; On delayed enhancement GRE T1WI, the lesions displayed irregularly circular enhancement in 14 patients and well-distributed enhancement in 4 patients. MRCP showed exten-sive bile and main pancreatic duct dilatation with typical "double-duct" sign in 8 patients. On 3D DCE MRA, we thought it was unresectable with more than half circumferential involvement of tumor to vessel,so that the portal, splenic and superior mesenteric veins were involved with 56% (10/18), 39% (7/18)and 67% (12/18), respectively. The celiac trunk and its main branches and superior mesenteric arteries were involved with 22% (4/18) and 17% (3/18), respectively. The pancreatic lesions in 2 cases could be completely resected in the evaluation of MR imaging, which was fitted to the findings of operation by pan-creatoduodenectomy. The pancreatic lesions in other 2 cases were partly, resected because there was tumor extension to superior mesenteric vein and/or artery. The tumors in the remaining 14 patients were too large and involved peripancreatic vessels or there were stomach or liver metastases, so these patients were only treated by choledochojejunostomy and gastrojejunstomy. Conclusion: The "all-in-one" MR approach including fast scanning sequences, fat suppression, MRCP and 3D DCE MRA provides the surgeon with diagnosis and assessment of resectability of tlm lesion prior to surgery of pancreatic carcinoma.展开更多
文摘Pagrosomus major larvae were exposed to the water soluble fraction of hydrocarbon in No.0 diesel oil (corresponding to No.2 fuel oil) at concentrations of 0, 0 17, 1.22 and 8 82 mg/L for up to 15 days. Larvae were sampled on days 9 and l5 of the experiment. Supernatants of viscera tissue extractions were assayed for biochemical response in terms of oxidative stress superoxide dismutase(SOD), activity of selenium dependant glutathione peroxidase(Se GPx) and catalase(Ca), and the concentration of reduced glutathione(GSH). On day 9 of exposure, statistically significant dose related increases in Se GPx and SOD activity, and GSH concentration were observed in all cases except for Se GPx activity under the highest dosage of hydrocarbon. However, on day l5 of exposure, a similar dose related response was only observed for Se GPx activity. GSH concentration decreased and SOD activity showed no statistical difference as compared to controls. However, a significant decrease in compared to day 9 Se GPx activity and GSH concentration, in contrast to increase SOD activity at day 15 as indicates an accelerated accumulation of H 2O 2 and potential oxidative damage under long term exposure of larvae to hydrocarbons. No statistical changes were observed in Ca activity throughout the experiment, possibly owing to the high efficiency of Se GPx. A recovery experiment was performed on indicating that the response of antioxidants measured tending to return to their control levels. These results prove the function of the antioxidant defense system of the larvae to the water soluble fraction of hydrocarbons in No.0 diesel oil.
文摘Objective: To study the value of multiple MR imaging techniques in the diagnosis of pancreatic carcinoma and the assessment of resectbility of the lesion. Methods: MR imaging was performed in 18 pa-tients with surgically and/or pathologically proven pancreatic carcinoma. GRE T1WI, TSE T2WI, GRE T1WI with fat suppression, delayed enhancement GRE T1WI, MRCP and 3D DCE MRA were used in MR scanning. Tumor involvement of the celiac trunk and its main branches, superior mesenteric artery,the portal, splenic and superior mesenteric veins were prospectively graded on a 0-4 scale based on cir-cumferential contiguity of tumor to vessel. Results: On GRE T1WI and TSE T2WI all the lesions showed slightly hypointense and hyperintense, respectively; On GRE T1WI with fat suppression, all the tumors obviously appeared hypointense; On delayed enhancement GRE T1WI, the lesions displayed irregularly circular enhancement in 14 patients and well-distributed enhancement in 4 patients. MRCP showed exten-sive bile and main pancreatic duct dilatation with typical "double-duct" sign in 8 patients. On 3D DCE MRA, we thought it was unresectable with more than half circumferential involvement of tumor to vessel,so that the portal, splenic and superior mesenteric veins were involved with 56% (10/18), 39% (7/18)and 67% (12/18), respectively. The celiac trunk and its main branches and superior mesenteric arteries were involved with 22% (4/18) and 17% (3/18), respectively. The pancreatic lesions in 2 cases could be completely resected in the evaluation of MR imaging, which was fitted to the findings of operation by pan-creatoduodenectomy. The pancreatic lesions in other 2 cases were partly, resected because there was tumor extension to superior mesenteric vein and/or artery. The tumors in the remaining 14 patients were too large and involved peripancreatic vessels or there were stomach or liver metastases, so these patients were only treated by choledochojejunostomy and gastrojejunstomy. Conclusion: The "all-in-one" MR approach including fast scanning sequences, fat suppression, MRCP and 3D DCE MRA provides the surgeon with diagnosis and assessment of resectability of tlm lesion prior to surgery of pancreatic carcinoma.