Controllable optical rogue waves in the femtosecond regime.

We derive analytical rogue wave solutions of variable-coefficient higher-order nonlinear Schrödinger equations describing the femtosecond pulse propagation via a transformation connected with the constant-coefficient Hirota equation. Then we discuss the propagation behaviors of controllable rogue waves, including recurrence, annihilation, and sustainment in a periodic distributed fiber system and an exponential dispersion decreasing fiber. Finally, we investigate nonlinear tunneling effects for rogue waves.

Management of delayed post-pancreaticoduodenectomy arterial bleeding: interventional radiological treatment first.

OBJECTIVE: To investigate the diagnosis and treatment of delayed post-pancreaticoduodenectomy arterial bleeding (DPPAB). METHODS: Records of 336 patients who underwent pancreaticoduodenectomy (PD) between January 2000 and December 2010 were retrospectively analyzed. Detailed data of patients with DPPAB were assessed by a thorough review of medical records. RESULTS: 14 patients developed DPPAB. The mean time interval between the initial surgery and DPPAB was 33 days (range 7-72). Three patients experienced sentinel bleeding 5-8 days before DPPAB. All DPPAB patients had intra-abdominal septic complications before bleeding. The overall prevalence of success of angiography and transcatheter arterial embolization (TAE) was 85.7% (12/14), including 3 patients who achieved complete hemostasis by TAE after unsuccessful re-laparotomy. The prevalence of mortality of DPPAB was 28.6% (4/14). After hemostasis was achieved, intra-abdominal septic complications were controlled by percutaneous catheter drainage or re-laparotomy with drain replacement. CONCLUSION: Angiography and TAE are recommended as the first-line diagnostic and treatment choice for DPPAB, respectively. Surgical intervention should be preserved to eliminate the cause of bleeding.

[A scoring system to predict ascites after hepatectomy for hepatocellular carcinoma].

OBJECTIVE: To establish a scoring system predicting the ascites postoperatively by analyzing the variant factors associated with massive ascites after hepatectomy in the patients with hepatocellular carcinoma (HCC). METHODS: From January 2005 to January 2010, 324 patients with HCC underwent hepatectomy were analyzed retrospectively. There were 282 male and 42 female, aging from 17 to 84 years (mean age, 54 years). They were divided into two groups according to the volume of ascites. Variant preoperative, intraoperative and postoperative factors were compared and a scoring system was established to predict the postoperative ascites. RESULTS: The univariate analyses revealed that various preoperative factors including prothrombin time, activated partial thromboplastin time, platelet count, albumin, aspartate aminotransferase had significantly difference in the two groups (P < 0.05). The operation time, intraoperative bleeding, hemihepatectomy or extended hemi-hepatectomy and the request of blood and serum transfusion had significantly difference in the two groups (P < 0.05). The multivariate analysis showed that the PLT, AST and the intraoperative plasma transfusion, hemihepatectomy or extended hemi-hepatectomy, the urine output and the drainage in the first postoperative day were independent factors (P < 0.05) for ascites. A scoring system was established based on the analysis. The specificity and the sensitivity were 86.2% and 83.3% respectively. CONCLUSION: Variant factors are associated with postoperative ascites for hepatocellular carcinoma and the scoring system established can predict the ascites after hepatectomy accurately.

[Association of hepatitis B virus infection and cirrhosis with liver metastasis in colorectal cancer].

OBJECTIVE: To explore the relationship of hepatitis B virus (HBV) infection and cirrhosis with liver metastasis in colorectal cancer. METHODS: Clinical date of 1176 colorectal cancer patients undergone surgical treatment in the Peking University School of Oncology between January 1999 and August 2004 were analyzed retrospectively to investigate the impact of HBV infection and cirrhosis on the occurrence of liver metastasis and prognosis of patients. RESULTS: The incidence of liver metastasis was 8.8% (10/114) in the HBV infection group and 23.9% (254/1062) in the non-infection group (P<0.01). The 5-year survival rates of these two groups were 54.2% and 60.7% ( P>0.05). The incidence of liver metastasis was 3.8% (1/26) in the cirrhotic group and 22.9% (263/1150) in the non-cirrhotic group (P<0.05). The 5-year survival rates of these two groups were 60.9% and 59.9% ( P>0.05). CONCLUSION: Both hepatitis B virus infection and cirrhosis are associated with less liver metastasis in colorectal cancer, but have no impact on the survival.

Long mesentericoportal vein resection and end-to-end anastomosis without graft in pancreaticoduodenectomy.

INTRODUCTION: The feasibility and safety of pancreaticoduodenectomy (PD) combined with long segmental mesentericoportal vein (MPV; >5 cm) resection and end-to-end anastomosis without graft has rarely been demonstrated. MATERIALS AND METHODS: Eight patients with pancreatic head adenocarcinoma underwent PD combined with long MPV resection between August 2006 and May 2008 in Peking University School of Oncology. RESULTS: By liver mobilization and Cattell-Braasch maneuver, direct and tension-free end-to-end anastomosis was easily performed even when the resected segment of the MPV was longer than 5 cm. All the eight patients experienced uneventful recovery without severe complications. CONCLUSIONS: PD with long MPV resection and direct end-to-end anastomoses is safe and effective.