MD Systems Research Articles

A New Efficient Method for Molecular Dynamics Simulation of Three-Body Potential Systems

Abstract An efficient order of N molecular dynamics method for the simulation of two-body and three-body systems is presented. Due to its high speed it enables one to simulate large MD systems on a mainframe and investigate some complex processes in terms which are closer to experimental conditions (e.g. crystal growth or ion implantation on relatively large-by MD standards-substrates).

Conditions for quantitation of HCV RNA in clinical practice: [formula omitted] The Johns Hopkins School of Medicine, Baltimore, Md and Roche Molecular Systems, Branchburg, NJ

Improvements in bile duct injury repairs have been shown in centres with specialized surgeons. The aim of the present study was to demonstrate the temporal change in the pattern of referral, technical variation associated with repair and long-term outcome of bile duct injuries at a tertiary referral centre in Mexico City.A retrospective case note review was performed. Patients were divided into two groups: group I (GI) 1990 to 2004 and group II (GII) 2005–2008, and appropriate statistical analysis undertaken.Over a 20-year period, 312 patients with iatrogenic bile duct injuries required surgical treatment (GI = 169, GII = 140 patients). All injuries were reconstructed using a Roux-en-Y hepaticojejunostomy. The proportion of patients who had undergone a laparoscopic cholecystectomy increased from 24% to 36% (P = 0.017) over the two time periods. In the second time period there was an increase in segment IV and V partial resections (P = 0.020), a reduction in the use of transanastomotic stents (42% to 2%, P = 0.001) and an increase in the proportion of patients requiring a neoconfluence (2% to 11%, P = 0.003). In the second time period, the number of patients requiring a hepatectomy during repair (2% to 1%, P = 0.001), a portoenterostomy (16% to 9%, P = 0.060) or a double-barrel hepatico-jejunostomy (5% to 1%, P = 0.045) significantly decreased. During follow-up, patients in the second time period had a reduction in the incidence of post-operative cholangitis (11% to 6%, P = 0.310) and the frequency of post-operative anastomotic stenoses (13% to 5%, P = 0.010). Mortality remained low throughout the series but was absent in the second group.Changes in technique and growing experience of the multidisciplinary team improved operative and long-term results of bile duct injury repair.