360 research outputs found
Surgical technique of orthotopic liver transplantation
Athough significant strides have been made in the surgical technique of orthotopic liver transplantation, numerous problems and nuisances are still encountered. Further surgical refinements will certainly evolve. The development of better preservation techniques, the use of intraoperative flowmeters, and the availability of new technologies, such as an artificial liver, should impact and advance the techniques of liver transplantation significantly and improve the overall results even further
Hepatic resection for metastatic colorectal adenocarcinoma: A proposal of a prognostic scoring system
Background: Hepatic resection for metastatic colorectal cancer provides excellent longterm results in a substantial proportion of patients. Although various prognostic risk factors have been identified, there has been no dependable staging or prognostic scoring system for metastatic hepatic tumors. Study Design: Various clinical and pathologic risk factors were examined in 305 consecutive patients who underwent primary hepatic resections for metastatic colorectal cancer. Survival rates were estimated by the Cox proportional hazards model using the equation: S(t) = [S(o)(t)](exp(R - R(o))), where S(o)(t) is the survival rate of patients with none of the identified risk factors and R(o) = 0. Results: Preliminary multivariate analysis revealed that independently significant negative prognosticators were: (1) positive surgical margins, (2) extrahepatic tumor involvement including the lymph node(s), (3) tumor number of three or more, (4) bilobar tumors, and (5) time from treatment of the primary tumor to hepatic recurrence of 30 months or less. Because the survival rates of the 62 patients with positive margins or extrahepatic tumor were uniformly very poor, multivariate analysis was repeated in the remaining 243 patients who did not have these lethal risk factors. The reanalysis revealed that independently significant poor prognosticators were: (1) tumor number of three or more, (2) tumor size greater than 8 cm, (3) time to hepatic recurrence of 30 months or less, and (4) bilobar tumors. Risk scores (R) for tumor recurrence of the culled cohort (n = 243) were calculated by summation of coefficients from the multivariate analysis and were divided into five groups: grade 1, no risk factors (R = 0); grade 2, one risk factor (R = 0.3 to 0.7); grade 3, two risk factors (R = 0.7 to 1.1); grade 4, three risk factors (R = 1.2 to 1.6); and grade 5, four risk factors (R > 1.6). Grade 6 consisted of the 62 culled patients with positive margins or extrahepatic tumor. Kaplan-Meier and Cox proportional hazards estimated 5-year survival rates of grade 1 to 6 patients were 48.3% and 48.3%, 36.6% and 33.7%, 19.9% and 17.9%, 11.9% and 6.4%, 0% and 1.1%, and 0% and 0%, respectively (p < 0.0001). Conclusions: The proposed risk-score grading predicted the survival differences extremely well. Estimated survival as determined by the Cox proportional hazards model was similar to that determined by the Kaplan-Meier method. Verification and further improvements of the proposed system are awaited by other centers or international collaborative studies
PXRF analysis of a yellow ochre quarry and rock art motifs in the Central Pilbara
The significance of ochre in Indigenous Australia is well documented. Several large, well-known quarries containing ochre that is highly sought after have been described in the archaeological literature, however less attention has been paid to smaller, regionally and locally significant quarries. In this paper a small yellow ochre quarry (VSTA_20140611_1) from the Central Pilbara, where evidence of paint preparation is preserved in the form of residues in two in situ grinding hollows, is described in order to address this oversight. Portable XRF (pXRF) analysis of the pigment in the quarry itself and the paint in the hollows was undertaken to understand the chemistry of the pigmentaceous minerals, to explore the taphonomy of the ochre seam, and to gauge variation within the source. Chemistry indicates that the VSTA_20140611_1 quarry is composed of an iron mineral (likely a hydroxide such as goethite), with Fe abundances consistently between 10.7 and 30%. Typical of the regional geology, the yellow pigment is consistently siliceous, with an Si abundance of between 5.8 and 20.4%. As there are no painted motifs in the rockshelter containing the VSTA_20140611_1 quarry, nor on the suitable BIF surfaces nearby, it is considered highly likely that the surviving paint produced on-site was used for either body decoration or the adornment of artefacts, rather than for rock art production. Nevertheless, the similarity in chemical composition between the VSTA_20140611_1 pigments and that of motifs painted in sites a few kilometres away suggests that, in addition to immediate processing and use at the site, ochre from this quarry may have been transported to rockshelters in the vicinity and used for rock art production
The Changing Presentation of Choledochal Cyst Disease: An Incidental Diagnosis
Background. Choledochal cysts are uncommon biliary lesions. Due to the evolution of imaging and laparoscopic surgery, we sought to describe our last 3 years experience with the presentation and management of choledochal cysts in adults. Methods. A retrospective review of a prospectively established database of adults who were managed for primary choledochal cyst disease between 2005 and 2008 was performed. Results. Between 8/2005 and 8/2008, 14 adults were managed for primary choledochal cyst disease. The average age was 41 years (range 17–86) and 79% were female. Presentations included biliary sepsis (3), pancreatitis (2), abdominal pain (3), or painless jaundice (1). Three patients had the cyst found during laparoscopic cholecystectomy, and two had an incidental finding after CT scan for an unrelated issue. The length of stay for those who had the cyst removed was 7.8 days (range 5–11). There were no operative or post-operative complications. Conclusions. Over the last 3 years 36% of our patients with choledochal cysts presented after incidental finding, either during a laparoscopic operation or after a CT scan for an unrelated problem. Increasing utilization of laparoscopy and CT scan for abdominal complaints has lead to a change in the pattern of presentation
Intraspecific Variation in Nutritional Composition Affects the Leaf Age Preferences of a Mammalian Herbivore
Ecologists have long been interested in how the nutritional composition of leaves changes as they age, and whether this affects herbivore feeding preferences. As a consequence, the literature abounds with reports that younger leaves contain higher concentrations of nitrogen and plant secondary metabolites (PSMs) than do older leaves. Most of these studies, however, base their conclusions on average values that often mean little to herbivores. We examined this issue in the well-studied marsupial-eucalypt system, using Eucalyptus melliodora and captive common brushtail possums (Trichosurus vulpecula) offered branches from individual trees containing both young and mature leaves. Like many plants, the concentrations of N and PSMs differed among individual E. melliodora. Although young leaves were, on average, "better defended" by the PSM sideroxylonal than were mature leaves, some trees produced leaves that were relatively undefended at both ages. In response, possums chose different proportions of young and mature leaves depending on the chemistry of the individual tree. Possums did not always prefer leaves with lower concentrations of sideroxylonal (mature leaves) or those with higher concentrations of available N (young leaves). Instead, the sideroxylonal concentration of young leaves dictated their choice: possums preferred young leaves with low sideroxylonal concentrations, but not with high concentrations. By skewing their feeding toward trees producing young leaves with low concentrations of PSMs, possums may influence plant fitness. Researchers will detect these potentially important interactions only if they are aware that measuring variation among plants discloses more information than do average relationships.The study was supported by funding from the Australian Research Council to KJM (DE120101263)
Nurses’ education, knowledge and perceptions of peripheral intravenous catheter management: A web-based, cross-sectional survey
Background: Peripheral intravenous catheters (PIVCs) are the most used invasive medical device. Unfortunately, PIVCs fail for a variety of reasons and failure often results in serious adverse events leading to patient discomfort, infection, delays in treatment, increased healthcare costs, and even death. In Australia, qualified nurses assess, manage, and remove a PIVC as part of their clinical role. To date, no study has described the current state of knowledge and confidence (self-efficacy) about PIVCs from the perspectives of qualified nurses working in Australian hospital settings. Aims: To describe the current state of knowledge and confidence (self-efficacy) about PIVC management from the perspectives of qualified nurses working in Australian hospital settings. To explore how these related to the education received by these nurses. Methods: An online cross-sectional survey. Findings: Qualified nurses in Australia thought that education about PIVCs was important and that it should be underpinned by evidence-based guidelines. Knowledge Test score for the sample was 12.4/17 (SD 2.1), this equates to a mean grade of 73.0%. Respondents reported very high levels of confidence about caring for a patient with a PIVC in situ. Conclusion: Despite the frequent and increasing use of PIVCs and importantly the documented adverse events associated with poor assessment, management and inappropriate removal, qualified nurses’ knowledge and confidence remain poorly reported. We demonstrated fundamental gaps in qualified nurses’ knowledge in relation to assessment, management, and removal of PIVCs
Liver transplantation before 1 year of age
Since 1981, 20 infants younger than 1 year of age received 26 orthotopic liver transplants. Immunosuppression was with cyclosporine and corticosteroids. Thirteen (65%) of the reciplents were discharged from the hospital. To date, 12 (60%) of the 20 reciplents are surviving, with follow-up of 1 to 56 months (average 14 months). The 5-year acluarial survival is 53.8%. The allograft liver function in the majority of surviving infants is excellent. The predominant causes of mortality were primary nonfunction of the allograft (three patients) and sepsis (three). Major morbidity was caused by hepatic artery thrombosis (five patients), gastrointestinal complications (six), biliary tract complications (five), and bacterial and viral infections (13). Six patients underwent retransplantation; three of these six survived. Results could be improved by prevention of hepatic artery thrombosis, by decreasing the incidence of sepsis, and by procurement of more and better suited pediatric donors. © 1987 The C. V. Mosby Company
Indications for pediatric liver transplantation
Two hundred fifty pediatric (<18 years of age) patients underwent orthotopic liver transplantation because of end-stage liver disease and were given combination therapy with cyclosporine and prednisone. The most common indications for transplantation in decreasing order of frequency were biliary atresia, inborn errors of metabolism, and postnecrotic cirrhosis. The 5-year actuarial survival for the entire group was 69.2%. Age and diagnosis did not influence survival. Infections were the most common cause of death, followed by liver failure and cerebrovascular accident. The impact of retransplantation on survival depends on the indication. The survival is better when retransplantation is carried out after rejection than because of technical complications, and the latter has a better survival than does primary graft nonfunction. The difference in survival among these groups is statistically significant. The quality of life for 164 of 173 survivors is good to excellent; only nine children are currently experiencing medical problems. A persistent problem in pediatric transplantation is the scarcity of small donors. © 1987 The C. V. Mosby Company
Boundaries of Semantic Distraction: Dominance and Lexicality Act at Retrieval
Three experiments investigated memory for semantic information with the goal of determining boundary conditions for the manifestation of semantic auditory distraction. Irrelevant speech disrupted the free recall of semantic category-exemplars to an equal degree regardless of whether the speech coincided with presentation or test phases of the task (Experiment 1) and occurred regardless of whether it comprised random words or coherent sentences (Experiment 2). The effects of background speech were greater when the irrelevant speech was semantically related to the to-be-remembered material, but only when the irrelevant words were high in output dominance (Experiment 3). The implications of these findings in relation to the processing of task material and the processing of background speech is discussed
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