The management of vasculature during extended radical resection for pancreatic cancer / 中华普通外科杂志

Objective To explore the clinical significance and operational methods during extended radical excision for pancreatic cancer combined with portal vein ( PV )/superior mesentery vein ( SMV ) resection,and to investigate the management of iatrogenic arterial injury. Methods Clinical date of 242 patients with pancreatic cancer undergoing extended radical excision were retrospectively analyzed. All cases were divided into three groups, patients with PV/SMV resection were in group A (n = 51 ), patients with iatrogenic arterial injury during operation were in group B(n =5) ,patients without resection of vessels werein group C (n = 186 ). Operating time、volume of intraoperative blood transfusion, time of vascular interruption、the mean hospitalization,postoperative complications and postoperative survival analysis among three groups were compared with each other. Results Operating time in group A、B and C were (442. 85 ± 102. 32 ) min, ( 348. 62 ± 92. 31 ) min and ( 315.00 ± 83.43 ) min respectively, volume of intraoperative blood transfusion were ( 1430. 83 ± 1092. 43 ) ml、( 1420. 22 ± 794. 41 ) ml and ( 928. 19 ±571.57) ml respectively,operating time and volume of intraoperative blood transfusion were of significantly difference(P <0. 05) among the 3 groups,there was no significant difference in the mean hospitalization and postoperative complications. The postoperative median survival period was 18.4 months for patients of pancreatic adenocarcinoma with PV/SMV resection, the postoperative median survival period was 16. 1 months without PV/SMV resection, there was no significant difference between these by postoperative survival analysis. In the 51 cases with vessel resection,7 cases underwent partial resection of the vascular wall,44 cases underwent segmental resection, reconstruction of the portal vein was performed by end-to-end anastomosis in 38 patients, stent graft in 6 cases, the mean length of the PV/SMV resection was (2. 92 ±1.35 ) cm; latrngenic arterial injury occurred during operation in 5 patients ( 1 in hepatic artery, 1 in superior mesenteric artery, 3 in celiac think), the artery was reconstructed by end-to-end anastomosis in 4 cases,repair in 1 case. Conclusions Active and reasonable operation for pancreatic cancer with PV/SMV resection is important for improving the rate of surgical resection and the quality of life. Because of complex topography,iatrogenic vascular injury may happened frequently.

Stretching Short Single-stranded DNA Adsorbed on Gold Surface by Atomic Force Microscope / 生物化学与生物物理进展

The manipulation and direct mechanical measurement of single DNA molecule could give much information about its elastic properties. Single stranded DNA (ssDNA) of 100 bases was adsorbed onto flat gold surface fabricated by depositing gold onto mica surface. Atomic force microscope (AFM) was used to observe the surface topography with different ssDNA concentration. Then the ssDNAs were stretched by AFM tip and in 50% cases ssDNAs could be stretched.Various kinds of force curves have been observed due to the different interaction between AFM tip and ssDNAs.