988 resultados para Tertiary treatment
Resumo:
Background: Laparoscopic cholecystectomy (LC) has become the first-line surgical treatment of calculous gall-bladder disease and the benefits over open cholecystectomy are well known. In the early years of LC, the higher rate of bile duct injuries compared with open cholecystectomy was believed to be due to the 'learning curve' and would dissipate with increased experience. The purpose of the present paper was to review a tertiary referral unit's experience of bile duct injuries induced by LC. Methods: A retrospective analysis was performed on all patients referred for management of an iatrogenic bile duct injury from 1981 to 2000. For injuries sustained at LC, details of time between LC and recognition of the injury, time from injury to definitive repair, type of injury, use of intraoperative cholangiography (IOC), definitive repair and postoperative outcome were recorded. The type of injury sustained at open cholecystectomy was similarly classified to allow the severity of injury to be compared. Results: There were 131 patients referred for management of an iatrogenic bile duct injury that occurred at open cholecystectomy (n = 62), liver resection (n = 5) and at LC (n = 64). Only 39% of bile duct injuries were recognized at the time of LC. Following conversion to open operation, half the subsequent procedures were considered inappropriate. When the injury was not recognized during LC, 70% of patients developed bile leak/peritonitis, almost half of whom were referred, whereas the rest underwent a variety of operative procedures by the referring surgeon. The remainder developed jaundice or abnormal liver function tests and cholangitis. An IOC was performed in 43% of cases, but failed to identify an injury in two-thirds of patients. The bile duct injuries that occurred at LC were of greater severity than with open cholecystectomy. Following definitive repair, there was one death (1.6%). Ninety-two per cent of patients had an uncomplicated recovery and there was one late stricture requiring surgical revision. Conclusions: The early prediction that the rate of injury during LC would decline substantially with increased experience has not been fulfilled. Bile duct injury that occurs at LC is of greater severity than with open cholecystectomy. Bile duct injury is recognized during LC in less than half the cases. Evidence is accruing that the use of cholangiography reduces the risk and severity of injury and, when correctly interpreted, increases the chance of recognition of bile duct injury during the procedure. Prevention is the key but, should an injury occur, referral to a specialist in biliary reconstructive surgery is indicated.
Resumo:
The effect of heat treatment on the structure of an Australian semi-anthracite char was studied in detail in the 850-1150degreesC temperature range using XRD, HRTEM, and electrical resistivity techniques. It was found that the carbon crystallite size in the char does not change significantly during heat treatment in the temperature range studied, for both the raw coal and its ash-free derivative obtained by acid treatment. However, the fraction of the organized carbon in the raw coal chars, determined by XRD, increased with increase of heat treatment time and temperature, while that for the ash-free coal chars remained almost unchanged. This suggests the occurrence of catalytic ordering during heat treatment, supported by the observation that the electrical resistivity of the raw coal chars decreased with heat treatment, while that of the ash-free coal chars did not vary significantly. Further confirmatory evidence was provided by high resolution transmission electron micrographs depicting well-organized carbon layers surrounding iron particles. It is also found that the fraction of organized carbon does not reach unity, but attains an apparent equilibrium value that increases with increase in temperature, providing an apparent heat of ordering of 71.7 kJ mol(-1) in the temperature range studied. Good temperature-independent correlation was found between the electrical resistivity and the organized carbon fraction, indicating that electrical resistivity is indeed structure sensitive. Good correlation was also found between the electrical resistivity and the reactivity of coal char. All these results strongly suggest that the thermal deactivation is the result of a crystallite-perfecting process, which is effectively catalyzed by the inorganic matter in the coal char. Based on kinetic interpretation of the data it is concluded that the process is diffusion controlled, most likely involving transport of iron in the inter-crystallite nanospaces in the temperature range studied. The activation energy of this transport process is found to be very low, at about 11.8 kJ mol(-1), which is corroborated by model-free correlation of the temporal variation of organized carbon fraction as well as electrical resistivity data using the superposition method, and is suggestive of surface transport of iron. (C) 2002 Elsevier Science Ltd. All rights reserved.
Resumo:
This article develops a weighted least squares version of Levene's test of homogeneity of variance for a general design, available both for univariate and multivariate situations. When the design is balanced, the univariate and two common multivariate test statistics turn out to be proportional to the corresponding ordinary least squares test statistics obtained from an analysis of variance of the absolute values of the standardized mean-based residuals from the original analysis of the data. The constant of proportionality is simply a design-dependent multiplier (which does not necessarily tend to unity). Explicit results are presented for randomized block and Latin square designs and are illustrated for factorial treatment designs and split-plot experiments. The distribution of the univariate test statistic is close to a standard F-distribution, although it can be slightly underdispersed. For a complex design, the test assesses homogeneity of variance across blocks, treatments, or treatment factors and offers an objective interpretation of residual plot.
Resumo:
Organic binders are used in premixes for powder metallurgy applications to prevent dusting and segregation. This is a particular problem for aluminium powder metallurgy because the dust is a potential safety hazard. The binder must also burn out completely at low temperatures in an inert environment and not react with the metal powders. It is demonstrated that cellulose acetate, polyvinyl acetate and polyvinyl alcohol are effective dedusting agents but they react with the metal powders during sintering and decrease the sintered density. Paraffin wan is an effect dedusting agent that provided die wall lubricity, does not interfere with sintering and increases tensile strength and ductility.
Resumo:
The efficacy of chloroquine treatment of uncomplicated Plasmodium falciparum malaria in East Timor was investigated via molecular tools. Genotyping of the polymorphic markers msp1 and msp2 was performed to investigate the number and type of parasite alleles in pre- and posttreatment blood samples collected from 48 patients. Patients were infected with a minimum of 8 msp1 and 14 msp2 allelic types of parasite, and 43% of the patients had more than one allelic type before treatment. The genotyping also revealed that 66.7% of the patients were infected with at least one identical allelic type of parasite before and after treatment and therefore were likely to have experienced recrudescence. All parasites in pre- and posttreatment blood samples carried the K76T mutation in pfcrt, regardless of the clinical response to chloroquine. The sequence polymorphism patterns in pfcrt in the majority of parasites examined were identical to those observed in Bougainville, Papua New Guinea.
Resumo:
A recent malaria epidemic in the Menoreh Hills of Central Java has increased concern about the re-emergence of endemic malaria on Java, which threatens the island's 120 million residents. A 28-day, in-vivo test of the efficacy of treatment of malaria with antimalarial drugs was conducted among 16 7 villagers in the Menoreh Hills. The treatments investigated, chloroquine (CQ) and sulfadoxine pyrimethamine (SP), constitute, respectively, the first- and second-line treatments for uncomplicated malaria in Indonesia. The prevalence of malaria among 1389 residents screened prior to enrollment was 33%. Treatment outcomes were assessed by microscopical diagnoses, PCR-based confirmation of the diagnoses, measurement of the whole-blood concentrations of CQ and desethylchloroquine (DCQ), and identification of the Plasmodium falciparum genotypes. The 28-day cumulative incidences of therapeutic failure for CQ and SP were, respectively, 47% (N = 36) and 22% (N = 50) in the treatment of P. falciparum, and 18% (N = 77) and 67% (N = 6) in the treatment of P. vivax. Chloroquine was thus an ineffective therapy for P. falciparum malaria, and the presence of CQ-resistant P. vivax and SP-resistant P. falciparum will further compromise efforts to control resurgent malaria on Java.
Resumo:
Spondylostrobus F. Mueller, which accommodates operculate fruit-stones reported only from the mid-Tertiary of Australia, is redefined on the basis of type and other specimens of the type species, S. smythii F. Mueller, and of specimens included in S. rozefeldsii sp. nov. The globose to ellipsoidal fruits have 3-6 locules symmetrically disposed around a massive fibrous axis. Each locule has a single anatropous ovule, axile placentation, and a dorsal germination operculum that extends from near the base to the apex. In possessing these characters Spondylostrobus more closely resembles operculate fruits within the tribe Spondiadeae (Anacardiaceae) than operculate fruits of other dicotyledonous families. Spondylostrobus has widespread distribution in Oligocene-Miocene sediments of eastern Australia. At many localities it is associated with fruit-stones having affinities with extant taxa that now occur in rainforests, monsoonal forests, and fringing communities of northern Australia. (C) 2002 Elsevier Science B.V. All rights reserved.
Resumo:
Evaluation of the performance of the APACHE III (Acute Physiology and Chronic Health Evaluation) ICU (intensive care unit) and hospital mortality models at the Princess Alexandra Hospital, Brisbane is reported. Prospective collection of demographic, diagnostic, physiological, laboratory, admission and discharge data of 5681 consecutive eligible admissions (1 January 1995 to 1 January 2000) was conducted at the Princess Alexandra Hospital, a metropolitan Australian tertiary referral medical/surgical adult ICU. ROC (receiver operating characteristic) curve areas for the APACHE III ICU mortality and hospital mortality models demonstrated excellent discrimination. Observed ICU mortality (9.1%) was significantly overestimated by the APACHE III model adjusted for hospital characteristics (10.1%), but did not significantly differ from the prediction of the generic APACHE III model (8.6%). In contrast, observed hospital mortality (14.8%) agreed well with the prediction of the APACHE III model adjusted for hospital characteristics (14.6%), but was significantly underestimated by the unadjusted APACHE III model (13.2%). Calibration curves and goodness-of-fit analysis using Hosmer-Lemeshow statistics, demonstrated that calibration was good with the unadjusted APACHE III ICU mortality model, and the APACHE III hospital mortality model adjusted for hospital characteristics. Post hoc analysis revealed a declining annual SMR (standardized mortality rate) during the study period. This trend was present in each of the non-surgical, emergency and elective surgical diagnostic groups, and the change was temporally related to increased specialist staffing levels. This study demonstrates that the APACHE III model performs well on independent assessment in an Australian hospital. Changes observed in annual SMR using such a validated model support an hypothesis of improved survival outcomes 1995-1999.
Resumo:
Background: The response of hepatocellular carcinoma (HCC) to therapy is often disappointing and new modalities of treatment are clearly needed. Active immunotherapy based on the injection of autologous dendritic cells (DC) co-cultured ex vivo with tumor antigens has been used in pilot studies in various malignancies such as melanoma and lymphoma with encouraging results. Methods: In the present paper, the preparation and exposure of patient DC to autologous HCC antigens and re-injection in an attempt to elicit antitumor immune responses are described. Results: Therapy was given to two patients, one with hepatitis C and one with hepatitis B, who had large, multiple HCC and for whom no other therapy was available. No significant side-effects were observed. The clinical course was unchanged in one patient, who died a few months later. The other patient, whose initial prognosis was considered poor, is still alive and well more than 3 years later with evidence of slowing of tumor growth based on organ imaging. Conclusions: It is concluded that HCC may be a malignancy worthy of DC trials and sufficient details in the present paper are given for the protocol to be copied or modified. (C) 2002 Blackwell Publishing Asia Pty Ltd.