939 resultados para Bones Radiography
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Osteoporosis imposes a tremendous burden on Australia : 1.2 million Australians have osteoporosis and 6.3 million have Osteopenia. In the 2007-08 financial year, 82000 Australians suffered fragility fractures, of Which >17000 were hip fractures. In the 2000-01 financial year, direct costs were estimated at $1.9 billion per year and an additional $5.6 billion on indirect costs. Osteoporosis was designated a National Health Priority Area in 2002; however, implementation of national plans has not yet matched the rhetoric in terms of urgency. Building healthy bones throughout life, the Osteoporosis Australia strategy to prevent osteoporosis throughout the life cycle, presents an evidence-informed set of recommendations for consumers, health care professionals and policymakers. The strategy was adopted by consensus at the Osteoporosis Australia Summit in Sydney, 20 October 2011. Primary objectives throughout the life cycle are: to maximise peak bone mass during childhood and adolescence to prevent premature bone loss and improve or maintain muscle mass, strength and functional capacity in healthy adults to prevent and treat osteoporosis in order to minimise the risk of suffering fragility fractures, and reduce falls risk, in older people. The recommendations focus on three affordable and important interventions to ensure people have adequate calcium intake, vitamin D levels and appropriate, physical activity throughout their lives. Recommendations relevant to all stages of life include: daily dietary calcium intakes should be consistent with Australian and New Zealand guidelines serum levels of vitamin D in the general population should be above 50 nmol/L in winter or early spring for optimal bone health regular weight-bearing physical activity, Muscle strengthening exercises and challenging balance/ mobility activities should be conducted in a safe environment.
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Emerging sciences, such as conceptual cost estimating, seem to have to go through two phases. The first phase involves reducing the field of study down to its basic ingredients - from systems development to technological development (techniques) to theoretical development. The second phase operates in the direction in building up techniques from theories, and systems from techniques. Cost estimating is clearly and distinctly still in the first phase. A great deal of effort has been put into the development of both manual and computer based cost estimating systems during this first phase and, to a lesser extent, the development of a range of techniques that can be used (see, for instance, Ashworth & Skitmore, 1986). Theoretical developments have not, as yet, been forthcoming. All theories need the support of some observational data and cost estimating is not likely to be an exception. These data do not need to be complete in order to build theories. As it is possible to construct an image of a prehistoric animal such as the brontosaurus from only a few key bones and relics, so a theory of cost estimating may possibly be found on a few factual details. The eternal argument of empiricists and deductionists is that, as theories need factual support, so do we need theories in order to know what facts to collect. In cost estimating, the basic facts of interest concern accuracy, the cost of achieving this accuracy, and the trade off between the two. When cost estimating theories do begin to emerge, it is highly likely that these relationships will be central features. This paper presents some of the facts we have been able to acquire regarding one part of this relationship - accuracy, and its influencing factors. Although some of these factors, such as the amount of information used in preparing the estimate, will have cost consequences, we have not yet reached the stage of quantifying these costs. Indeed, as will be seen, many of the factors do not involve any substantial cost considerations. The absence of any theory is reflected in the arbitrary manner in which the factors are presented. Rather, the emphasis here is on the consideration of purely empirical data concerning estimating accuracy. The essence of good empirical research is to .minimize the role of the researcher in interpreting the results of the study. Whilst space does not allow a full treatment of the material in this manner, the principle has been adopted as closely as possible to present results in an uncleaned and unbiased way. In most cases the evidence speaks for itself. The first part of the paper reviews most of the empirical evidence that we have located to date. Knowledge of any work done, but omitted here would be most welcome. The second part of the paper presents an analysis of some recently acquired data pertaining to this growing subject.
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This dissertation analyses how physical objects are translated into digital artworks using techniques which can lead to ‘imperfections’ in the resulting digital artwork that are typically removed to arrive at a ‘perfect’ final representation. The dissertation discusses the adaptation of existing techniques into an artistic workflow that acknowledges and incorporates the imperfections of translation into the final pieces. It presents an exploration of the relationship between physical and digital artefacts and the processes used to move between the two. The work explores the 'craft' of digital sculpting and the technology used in producing what the artist terms ‘a naturally imperfect form’, incorporating knowledge of traditional sculpture, an understanding of anatomy and an interest in the study of bones (Osteology). The outcomes of the research are presented as a series of digital sculptural works, exhibited as a collection of curiosities in multiple mediums, including interactive game spaces, augmented reality (AR), rapid prototype prints (RP) and video displays.
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Previous research employing indirect measures of arch structure, such as those derived from footprints, have indicated that obesity results in a “flatter” foot type. In the absence of radiographic measures, however, definitive conclusions regarding the osseous alignment of the foot cannot be made. We determined the effect of body mass index (BMI) on radiographic and footprint‐based measures of arch structure. The research was a cross‐sectional study in which radiographic and footprint‐based measures of foot structure were made in 30 subjects (10 males, 20 female) in addition to standard anthropometric measures of height, weight, and BMI. Multiple (univariate) regression analysis demonstrated that both BMI ( β = 0.39, t 26 = 2.12, p = 0.04) and radiographic arch alignment ( β = 0.51, t 26 = 3.32, p < 0.01) were significant predictors of footprint‐based measures of arch height after controlling for all variables in the model ( R 2 = 0.59, F 3,26 = 12.3, p < 0.01). In contrast, radiographic arch alignment was not significantly associated with BMI ( β = −0.03, t 26 = −0.13, p = 0.89) when Arch Index and age were held constant ( R 2 = 0.52, F 3,26 = 9.3, p < 0.01). Adult obesity does not influence osseous alignment of the medial longitudinal arch, but selectively distorts footprint‐based measures of arch structure. Footprint‐based measures of arch structure should be interpreted with caution when comparing groups of varying body composition.
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This presentation is a personal perspective of the requirements for attaining Fellowship of the Australian Institute of Radiography. It describes the criteria and offers a personal insight into the Fellowship Journey
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This presentation uses a case study approach to describe the Nuss procedure for pectus excavatum - and implications for imaging
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This thesis presents a study using mechanical testing techniques combined with advanced computational methods to examine the mechanics of bone. It contributes novel observations and analysis of how bones fail at the microscopic level, which will be valuable in furthering our understanding and the treatment of bone damage in health and disease, including osteoporosis.
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Purpose: Prior to 2009, one of the problems faced by radiation therapists who supervised and assessed students on placement in Australian clinical centres, was that each of the six Australian universities where Radiation Therapy (RT) programmes were conducted used different clinical assessment and reporting criteria. This paper describes the development of a unified national clinical assessment and reporting form that was implemented nationally by all six universities in 2009. Methods: A four phase methodology was used to develop the new assessment form and user guide. Phase 1 included university consensus around domains of student practice and assessment, and alignment with national competency standards; Phase 2 was a national consensus workshop attended by radiation therapists involved in student supervision and assessment; Phase 3 was an action research re-iterative Delphi technique involving two rounds of a mail-out to gain further expert consensus; and stage 4 was national piloting of the developed assessment form. Results: The new assessment form includes five main domains of practice and 19 sub-domain criteria which students are assessed against during placement. Feedback from the pilot centre participants was positive, with the new form being assessed to be comprehensive and complemented by the accompanying user guide. Conclusion: The new assessment form has improved both the formative and summative assessment of students on placement, as well as enhancing the quality of feedback to students and the universities. The new national form has high acceptance from the Australian universities and has been subject to wide review by the profession.
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Introduction Patients with virally mediated head and neck cancer (VMHNC) often present with advanced nodal disease that is highly radioresponsive as demonstrated by tumour and nodal regression during treatment. The resultant changes may impact on the planned dose distribution and so adversely affect the therapeutic ratio. The aim of this study was to evaluate the dosimetric effect of treatment-induced anatomical changes in VMHNC patients who had undergone a re-plan. Methods Thirteen patients with virally mediated oropharyngeal or nasopharyngeal cancer who presented for definitive radiotherapy between 2005 and 2010 and who had a re-plan generated were investigated. The dosimetric effect of anatomical changes, was quantified by comparing dose volume histograms (DVH) of primary and nodal gross target volumes and organs at risk (OAR), including spinal cord and parotid glands, from the original plan and a comparison plan. Results Eleven 3DCRT and 2 IMRT plans were evaluated. Dose to the spinal cord and brainstem increased by 4.1% and 2.6%, respectively. Mean dose to the parotid glands also increased by 3.5%. In contrast, the dose received by 98% of the primary and nodal gross tumour volumes decreased by 0.15% and 0.3%, respectively when comparing the initial treatment plan to the comparison plan. Conclusion In this study, treatment-induced anatomical changes had the greatest impact on OAR dose with negligible effect on the dose to nodal gross tumour volumes. In the era of intensity modulated radiotherapy (IMRT), accounting for treatment-induced anatomical changes is important as focus is placed on minimising the acute and long-term side effects of treatment.
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Injured bone initiates the healing process by forming a blood clot at the damaged site. However, in severe damage, synthetic bone implants are used to provide structural integrity and restore the healing process. The implant unavoidably comes into direct contact with whole blood, leading to a blood clot formation on its surface. Despite this, most research in bone tissue engineering virtually ignores the important role of a blood clot in supporting healing. Surface chemistry of a biomaterial is a crucial property in mediating blood-biomaterials interactions, and hence the formation of the resultant blood clot. Surfaces presenting mixtures of functional groups carboxyl (–COOH) and methyl (–CH3) have been shown to enhance platelet response and coagulation activation, leading to the formation of fibrin fibres. In addition, it has been shown that varying the compositions of these functional groups and the length of alkyl groups further modulate the immune complement response. In this study, we hypothesised that a biomaterial surface with mixture of –COOH/–CH3(methyl), –CH2CH3 (ethyl) or –(CH2)3CH3 (butyl) groups at different ratios would modulate blood coagulation and complement activation, and eventually tailor the structural and functional properties of the blood clot formed on the surface, which subsequently impacts new bone formation. Firstly, we synthesised a series of materials composed of acrylic acid (AA), and methyl (MMA), ethyl (EMA) or butyl methacrylates (BMA) at different ratios and coated on the inner surfaces of incubation vials. Our surface analysis showed that the amount of –COOH groups on the surface coatings was lower than the ratios of AA prepared in the materials even though the surface content of –COOH groups increased with increasing in AA ratios. It was indicated that the surface hydrophobicity increased with increasing alkyl chain length: –CH 3 > –CH2CH3 > –(CH2)3CH3, and decreased with increasing –COOH groups. No significant differences in surface hydrophobicity was found on surfaces with –CH3 and –CH2CH3 groups in the presence of –COOH groups. The material coating was as smooth as uncoated glass and without any major flaws. The average roughness of material-coated surface (3.99 ± 0.54 nm) was slightly higher than that of uncoated glass surface (2.22 ± 0.29 nm). However, no significant differences in surface average roughness was found among surfaces with the same functionalities at different –COOH ratios nor among surfaces with different alkyl groups but the same –COOH ratios. These suggested that the surface functional groups and their compositions had a combined effect on modulating surface hydrophobicity but not surface roughness. The second part of our study was to investigate the effect of surface functional groups and their compositions on blood cascade activation and structural properties of the formed clots. It was found that surfaces with –COOH/–(CH2)3CH3 induced a faster coagulation activation than those with –COOH/–CH3 and –CH2CH3, regardless of the –COOH ratios. An increase in –COOH ratios on –COOH/–CH3 and –CH2CH3 surfaces decreased the rate of activation. Moreover, all material-coated surfaces markedly reduced the complement activation compared to uncoated glass surfaces, and the pattern of complement activation was entirely similar to that of surface-induced coagulation, suggesting there is an interaction between two cascades. The clots formed on material-coated surfaces had thicker fibrin with a tighter network at the exterior when compared to uncoated glass surfaces. Compared to the clot exteriors, thicker fibrins with a loose network were found in clot interiors. Coated surfaces resulted in more rigid clots with a significantly slower fibrinolysis after 1 h of lysis when compared to uncoated glass surfaces. Significant differences in fibrinolysis after 1 h of lysis among clots on material-coated surfaces correlated well with the differences in fibrin thickness and density at clot exterior. In addition, more growth factors were released during clot formation than during clot lysis. From an intact clot, there was a correlation between the amount of PDGF-AB release and fibrin density. Highest amount of PDGF-AB was released from clots formed on surfaces with 40% –COOH/60% –CH 3 (i.e. 65MMA). During clot lysis, the release of PDGF-AB also correlated with the fibrinolytic rate while the release of TGF-â1 was influenced by the fibrin thickness. This suggested that different clot structures led to different release profiles of growth factors in clot intact and degrading stages. We further validated whether the clots formed on material-coatings provide the microenvironment for improved bone healing by using a rabbit femoral defect model. In this pilot study, the implantation of clots formed on 65MMA coatings significantly increased new bone formation with enhanced chondrogenesis, osteoblasts activity and vascularisation, but decreased inflammatory macrophage number at the defects after 4 weeks when compared to commercial bone grafts ChronOSTM â-TCP granules. Empty defects were observed when blood clot formation was inhibited. In summary, our study demonstrated that surface functional groups and their relative ratios on material coatings synergistically modulate activation of blood cascades, resultant fibrin architecture, rigidity, susceptibility to fibrinolysis as well as growth factor release of the formed clots, which ultimately alter the healing microenvironment of injured bones.
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Runt related transcription factor 2 (RUNX2) is a key regulator of osteoblast differentiation. Several variations within RUNX2 have been found to be associated with significant changes in BMD, which is a major risk factor for fracture. In this study we report that an 18bp deletion within the polyalanine tract (17A>11A) of RUNX2 is significantly associated with fracture. Carriers of the 11A allele were found to be nearly twice as likely to have sustained fracture. Within the fracture category, there was a significant tendency of 11A carriers to present with fractures of bones of intramembranous origin compared to bones of endochondral origin (p=0.005). In a population of random subjects, the 11A allele was associated with decreased levels of serum collagen cross links (CTx, p=0.01), suggesting decreased bone turnover. The transactivation function of the 11A allele was quantitatively decreased. Interestingly, we found no effect of the 11A allele on BMD at multiple skeletal sites, although these were not the sites where a relationship with fracture was most evident. These findings suggest that the 11A allele is a biologically relevant polymorphism that influences serum CTx and confers enhanced fracture risk in a site-selective manner related to intramembranous bone ossification.
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This project’s aim was to create new experimental models in small animals for the investigation of infections related to bone fracture fixation implants. Animal models are essential in orthopaedic trauma research and this study evaluated new implants and surgical techniques designed to improve standardisation in these experiments, and ultimately to minimise the number of animals needed in future work. This study developed and assessed procedures using plates and inter-locked nails to stabilise fractures in rabbit thigh bones. Fracture healing was examined with mechanical testing and histology. The results of this work contribute to improvements in future small animal infection experiments.
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To understand the survival status of cancer patients and influencing factors, an analysis was undertaken using data of 6450 cancer patients living in Linqu County, Shandong, diagnosed between 1993 and 1999. Survival rates were calculated using life table method with SAS 9.0 software. Overall 1-5 year survival rates for all patients were 53.16%, 28.65%, 21.57%, 18.36% and 17.87%, respectively. Cancers with a 5-year survival rate over 25% included ovarium, breast, uterus, stomach and colorectal cancers. Cancers with a 5-year survival lower than 10% were cancers on liver, cervical, lung and bones.Survival rates differed significantly across gender, age of onset, economic status, year of diagnosis and evidence of diagnosis. Patients' economic status, age of diagnosis and year of diagnosis seem to have strong effects on survival. [目的] 了解临朐县恶性肿瘤患者生存现状,探讨影响生存率的因素. [方法] 对临朐县1993~1999年发病的6450例肿瘤患者的生存资料进行分析,利用SAS9.0软件寿命表法计算生存率. [结果] 临朐县1993~1999年的恶性肿瘤患者1~5年生存率分别为53.16%、28.65%、21.57%、18.36%和17.87%,5年生存率超过25%的恶性肿瘤有卵巢癌、乳腺癌、宫体癌、胃癌、结直肠癌,5年生存率低于10%的有肝癌、宫颈癌、肺癌、骨恶性肿瘤.不同性别、发病年龄、经济状况、诊断时间和诊断依据的恶性肿瘤生存率有显著性差异. [结论] 患者经济条件、诊断年龄和诊断时间影响恶性肿瘤生存率.
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Fossils and sediments preserved in caves are an excellent source of information for investigating impacts of past environmental changes on biodiversity. Until recently studies have relied on morphology-based palaeontological approaches, but recent advances in molecular analytical methods offer excellent potential for extracting a greater array of biological information from these sites. This study presents a thorough assessment of DNA preservation from late Pleistocene–Holocene vertebrate fossils and sediments from Kelly Hill Cave Kangaroo Island, South Australia. Using a combination of extraction techniques and sequencing technologies, ancient DNA was characterised from over 70 bones and 20 sediment samples from 15 stratigraphic layers ranging in age from >20 ka to ∼6.8 ka. A combination of primers targeting marsupial and placental mammals, reptiles and two universal plant primers were used to reveal genetic biodiversity for comparison with the mainland and with the morphological fossil record for Kelly Hill Cave. We demonstrate that Kelly Hill Cave has excellent long-term DNA preservation, back to at least 20 ka. This contrasts with the majority of Australian cave sites thus far explored for ancient DNA preservation, and highlights the great promise Kangaroo Island caves hold for yielding the hitherto-elusive DNA of extinct Australian Pleistocene species.
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Extrapulmonary small cell and small cell neuroendocrine tumors of unknown primary site are, in general, aggressive neoplasms with a short median survival. Like small cell lung cancer (SCLC), they often are responsive to chemotherapy and radiotherapy. Small cell lung cancer and well differentiated neuroendocrine carcinomas of the gastrointestinal tract and pancreas tend to express somatostatin receptors. These tumors may be localized in patients by scintigraphic imaging using radiolabeled somatostatin analogues. A patient with an anaplastic neuroendocrine small cell tumor arising on a background of multiple endocrine neoplasia type 1 syndrome is reported. The patient had a known large pancreatic gastrinoma and previously treated parathyroid adenopathy. At presentation, there was small cell cancer throughout the liver and skeleton. Imaging with a radiolabeled somatostatin analogue, 111In- pentetreotide (Mallinckrodt Medical B. V., Petten, Holland), revealed all sites of disease detected by routine biochemical and radiologic methods. After six cycles of chemotherapy with doxorubicin, cyclophosphamide, and etoposide, there was almost complete clearance of the metastatic disease. 111In-pentetreotide scintigraphy revealed uptake consistent with small areas of residual disease in the liver, the abdomen (in mesenteric lymph nodes), and posterior thorax (in a rib). The primary gastrinoma present before the onset of the anaplastic small cell cancer showed no evidence of response to the treatment. The patient remained well for 1 year and then relapsed with brain, lung, liver, and skeletal metastases. Despite an initial response to salvage radiotherapy and chemotherapy with carboplatin and dacarbazine, the patient died 6 months later.