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1.
Breast Dis ; 37(3): 163-167, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29376843

RESUMO

Metastases to the breast are very uncommon as compared to primary tumours. Breast is an unusual site for metastasis from renal cell carcinoma. Only occasional cases are reported in the literature. These metastases must be clearly diagnosed as the treatment of primary breast cancer and metastases differs markedly. Treatment of isolated metastases from renal cell carcinoma is usually surgical resection. We report two cases of isolated metachronous metastases to breast from renal cell carcinoma.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/secundário , Carcinoma de Células Renais/diagnóstico , Carcinoma de Células Renais/secundário , Neoplasias Renais/patologia , Idoso , Idoso de 80 Anos ou mais , Mama/patologia , Mama/cirurgia , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/cirurgia , Feminino , Humanos
2.
Int J Numer Methods Fluids ; 75(8): 591-607, 2014 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-25892840

RESUMO

We investigate the relative performance of a second-order Adams-Bashforth scheme and second-order and fourth-order Runge-Kutta schemes when time stepping a 2D linear advection problem discretised using a spectral/hp element technique for a range of different mesh sizes and polynomial orders. Numerical experiments explore the effects of short (two wavelengths) and long (32 wavelengths) time integration for sets of uniform and non-uniform meshes. The choice of time-integration scheme and discretisation together fixes a CFL limit that imposes a restriction on the maximum time step, which can be taken to ensure numerical stability. The number of steps, together with the order of the scheme, affects not only the runtime but also the accuracy of the solution. Through numerical experiments, we systematically highlight the relative effects of spatial resolution and choice of time integration on performance and provide general guidelines on how best to achieve the minimal execution time in order to obtain a prescribed solution accuracy. The significant role played by higher polynomial orders in reducing CPU time while preserving accuracy becomes more evident, especially for uniform meshes, compared with what has been typically considered when studying this type of problem.© 2014. The Authors. International Journal for Numerical Methods in Fluids published by John Wiley & Sons, Ltd.

3.
IEEE Trans Vis Comput Graph ; 18(12): 2325-34, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26357140

RESUMO

This paper presents the Element Visualizer (ElVis), a new, open-source scientific visualization system for use with high-order finite element solutions to PDEs in three dimensions. This system is designed to minimize visualization errors of these types of fields by querying the underlying finite element basis functions (e.g., high-order polynomials) directly, leading to pixel-exact representations of solutions and geometry. The system interacts with simulation data through runtime plugins, which only require users to implement a handful of operations fundamental to finite element solvers. The data in turn can be visualized through the use of cut surfaces, contours, isosurfaces, and volume rendering. These visualization algorithms are implemented using NVIDIA's OptiX GPU-based ray-tracing engine, which provides accelerated ray traversal of the high-order geometry, and CUDA, which allows for effective parallel evaluation of the visualization algorithms. The direct interface between ElVis and the underlying data differentiates it from existing visualization tools. Current tools assume the underlying data is composed of linear primitives; high-order data must be interpolated with linear functions as a result. In this work, examples drawn from aerodynamic simulations-high-order discontinuous Galerkin finite element solutions of aerodynamic flows in particular-will demonstrate the superiority of ElVis' pixel-exact approach when compared with traditional linear-interpolation methods. Such methods can introduce a number of inaccuracies in the resulting visualization, making it unclear if visual artifacts are genuine to the solution data or if these artifacts are the result of interpolation errors. Linear methods additionally cannot properly visualize curved geometries (elements or boundaries) which can greatly inhibit developers' debugging efforts. As we will show, pixel-exact visualization exhibits none of these issues, removing the visualization scheme as a source of uncertainty for engineers using ElVis.

4.
Med Image Anal ; 15(4): 640-9, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20674466

RESUMO

State of the art radiation treatment methods such as hypo-fractionated stereotactic body radiation therapy (SBRT) can successfully destroy tumor cells and avoid damaging healthy tissue by delivering high-level radiation dose that precisely conforms to the tumor shape. Though these methods work well for stationary tumors, SBRT dose delivery is particularly susceptible to organ motion, and few techniques capable of resolving and compensating for respiratory-induced organ motion have reached clinical practice. The current treatment pipeline cannot accurately predict nor account for respiratory-induced motion in the abdomen that may result in significant displacement of target lesions during the breathing cycle. Sensitivity of dose deposition to respiratory-induced organ motion represents a significant challenge and may account for observed discrepancies between predictive treatment plan indicators and clinical patient outcomes. Improved treatment-planning and delivery of SBRT requires an accurate prediction of dose deposition uncertainties resulting from respiratory motion. To accomplish this goal, we developed a framework that models both organ displacement in response to respiration and the underlying random variations in patient-specific breathing patterns. Our organ deformation model is a four-dimensional maximum a posteriori (MAP) estimation of tissue deformation as a function of chest wall amplitudes computed from clinically obtained respiratory-correlated computed tomography (RCCT) images. We characterize patient-specific respiration as the probability density function (PDF) of chest wall amplitudes and model patient breathing patterns as a random process. We then combine the patient-specific organ motion and stochastic breathing models to calculate the resulting variability in radiation dose accumulation. This process allows us to predict uncertainties in dose delivery in the presence of organ motion and identify tissues at risk of receiving insufficient or harmful levels of radiation.


Assuntos
Carga Corporal (Radioterapia) , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Proteção Radiológica/métodos , Mecânica Respiratória , Técnicas de Imagem de Sincronização Respiratória/métodos , Tomografia Computadorizada por Raios X/métodos , Humanos , Movimento (Física) , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Radioterapia Assistida por Computador/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
5.
BMJ Case Rep ; 20102010 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-22767625

RESUMO

A 52-year-old woman was admitted with neutropenic sepsis, 3 days following the final cycle of adjuvant chemotherapy for breast cancer. Her condition deteriorated with progressive abdominal distension, bilious vomiting and diarrhoea. Abdominal examination revealed a mild degree of peritonism. Five days later she passed a small bowel cast per rectum, showing gross fungal contamination on histology. She was managed conservatively with antibiotics and antifungal medications and nutritional support.


Assuntos
Quimioterapia Adjuvante/efeitos adversos , Mucosa Intestinal/microbiologia , Intestino Delgado , Micoses/diagnóstico , Antibacterianos/uso terapêutico , Antifúngicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Defecação , Progressão da Doença , Feminino , Humanos , Pessoa de Meia-Idade , Neutropenia/tratamento farmacológico , Neutropenia/etiologia , Sepse/tratamento farmacológico , Sepse/etiologia
6.
Artigo em Inglês | MEDLINE | ID: mdl-17271803

RESUMO

Electrical activity in biological media can be described in a mathematical way, which is applicable to computer-based simulation. Biophysically mathematical descriptions provide important insights into the electrical and electrophysiological properties of cells, tissues, and organs. Examples of these descriptions are Maxwell's and Poisson's equations for electromagnetic and electric fields. Commonly, numerical techniques are applied to calculate electrical fields, e.g. the finite element method. Finite elements can be classified on the order of the underlying Interpolation. High-order finite elements provide enhanced geometric flexibility and can increase the accuracy of a solution. The aim of this work is the design of a framework for describing and solving high-order finite elements in the SCIRun/BioPSE software system, which allows geometric modeling, simulation, and visualization for solving bioelectric field problems. Currently, only low-order elements are supported. Our design for high-order elements concerns interpolation of geometry and physical fields. The design is illustrated by an implementation of one-dimensional elements with cubic interpolation of geometry and field variables.

8.
Injury ; 29(3): 177-82, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9709417

RESUMO

It has been suggested that over 30 per cent of splenic injuries are suitable for conservative management by non-operative treatment and splenorrhaphy; splenic conservation avoids the risk of overwhelming post-splenectomy infection. In this study, injuries of the spleen have been retrospectively analysed for a 10 year period. In the first 5 years the spleen was conserved in only 6/45 (15 per cent) of patients with blunt injury (three non-operative, three splenorrhaphy). In the second 5 years of the study, the spleen was conserved in significantly more patients with blunt trauma, 25 of 61 (41 per cent). This change has been a result of increased non-operative management which has been successful in the majority of cases (20/22). This has been associated with the increased use of abdominal ultrasound. The rate of splenorrhaphy has not changed significantly, five patients compared with three in the previous 5 years. Non-operative management may be increasingly appropriate as less severe splenic injuries are being detected with an increased use of ultrasound. Splenic injury is not a mandatory indication for laparotomy; non-operative management of splenic injuries should be considered in selected patients who are haemodynamically stable and can be closely monitored.


Assuntos
Baço/lesões , Ferimentos por Arma de Fogo/terapia , Ferimentos não Penetrantes/terapia , Ferimentos Perfurantes/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Esplenectomia , Ferimentos por Arma de Fogo/cirurgia , Ferimentos não Penetrantes/cirurgia , Ferimentos Perfurantes/cirurgia
9.
Injury ; 29(1): 65-71, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9659485

RESUMO

Over a 3 year period all severely injured blunt trauma patients who were investigated with abdominal ultrasound examinations (AUS) or diagnostic peritoneal lavage (DPL) to exclude intra-abdominal injury were evaluated. The ultrasound examinations were performed by radiologists in 220 severely injured patients (20 of whom also had DPL). The overall sensitivity and specificity of abdominal ultrasound were 82.7% and 99.5%, respectively. The sensitivity increased to 89.1% by repeat scanning. In comparison, 72 DPLs were performed in severely injured patients; the overall sensitivity and specificity of DPL were 82.8% and 97.2%, respectively. DPL resulted in more non-therapeutic laparotomies, 9/25 (36%) compared with 3/23 (13%) with AUS. Abdominal ultrasound is now the first line investigation at this centre for evaluation of possible intra-abdominal injury in injured patients.


Assuntos
Traumatismos Abdominais/diagnóstico , Ferimentos não Penetrantes/complicações , Traumatismos Abdominais/diagnóstico por imagem , Humanos , Escala de Gravidade do Ferimento , Lavagem Peritoneal , Estudos Prospectivos , Sensibilidade e Especificidade , Ultrassonografia , Ferimentos não Penetrantes/diagnóstico por imagem
10.
J Appl Microbiol ; 84(5): 802-10, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9674134

RESUMO

The bactericidal activity of gaseous ozone was investigated using a commercial ozone generator. Five species of fish bacteria, Pseudomonas putida, Shewanella putrefaciens, Brochothrix thermosphacta, Enterobacter sp. and Lactobacillus plantarum, were inoculated on agar surfaces and exposed to different ozonation times in a gas chamber. Results showed ozone in relatively low concentrations (< 0.27 x 10(-3) g l-1) was an effective bactericide of vegetative cells of the five fish bacteria. The age of the cell culture was shown to influence the cell response following exposure. Survival rate was not linearly related to ozonation time, but exhibited biphasic death over an extended period. Similar bactericidal effects were observed on fish skin treated with ozone daily in the laboratory, with decreases of 1.0 log cfu cm-2 for the micro-organisms studied. Whole fish treated daily in the laboratory using a commercial ozone generator showed improved scores for sensory analyses compared with the controls. The results were statistically significant. Fish treated on board ships were also analysed for microbiological and sensory changes. Controls were obtained from a similar vessel without the ozone facility in the hold. Similar trends to those recorded in the laboratory for the microbiological and sensory results on ozonated fish were observed.


Assuntos
Ozônio/farmacologia , Perciformes/microbiologia , Animais , Contagem de Colônia Microbiana , Relação Dose-Resposta a Droga , Enterobacter/efeitos dos fármacos , Enterobacter/crescimento & desenvolvimento , Lactobacillus/efeitos dos fármacos , Lactobacillus/crescimento & desenvolvimento , Músculos/microbiologia , Pseudomonas putida/efeitos dos fármacos , Pseudomonas putida/crescimento & desenvolvimento , Pele/microbiologia
12.
Postgrad Med J ; 73(859): 303-4, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9196708

RESUMO

We report a case of massive rectal haemorrhage arising from a single ectatic arterial vessel above the haemorrhoidal cushion in normal rectal mucosa. Use of an anal retractor enable identification of the bleeding vessel and avoided a major laparatomy.


Assuntos
Hemorragia Gastrointestinal/cirurgia , Doenças Retais/cirurgia , Reto/irrigação sanguínea , Idoso , Artérias , Humanos , Masculino
13.
Br J Surg ; 83(9): 1248-51, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8983619

RESUMO

A prospective audit of trauma patients seen or treated by the Department of General Surgery at the North Staffordshire Hospital Trauma Centre has been carried out, examining both the effect of a newly established trauma centre on overall workload and the outcome of patients admitted with severe injury. Trauma comprised approximately 2 per cent of the overall general surgical emergency workload. General surgeons were involved in the assessment of 25 per cent of severely injured patients but overall operated on fewer than 10 per cent of patients in this group. No patient died during the study period as a consequence of missed or inadequately treated intra-abdominal injury. These data suggest that there is insufficient work to justify specialist general surgical trauma surgeons in the UK. When general surgical intervention is required, however, it is usually vital and potentially life-saving.


Assuntos
Cirurgia Geral , Papel do Médico , Centros de Traumatologia , Mortalidade Hospitalar , Humanos , Admissão do Paciente/estatística & dados numéricos , Estudos Prospectivos , Procedimentos Cirúrgicos Operatórios/estatística & dados numéricos , Reino Unido , Recursos Humanos
14.
Postgrad Med J ; 72(847): 304-6, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8761508

RESUMO

Stromal tumours of the rectum and anal canal are rare, representing 0.02-0.03% of malignant neoplasms in the region. Current advice in their management is treatment by abdomino-perineal resection. We report a case of malignant spindle cell stromal tumour in which adequate clearance was obtained whilst preserving the anal sphincter, using a posterior parasacral approach.


Assuntos
Leiomioma/cirurgia , Neoplasias Retais/cirurgia , Adulto , Feminino , Humanos , Leiomioma/patologia , Leiomiossarcoma/patologia , Leiomiossarcoma/cirurgia , Masculino , Neoplasias Retais/patologia , Resultado do Tratamento
15.
Int J Food Microbiol ; 25(2): 169-77, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7547148

RESUMO

The development of a liquid medium for the detection of Listeria spp. by capacitance monitoring of food samples previously enriched in UVM 1 broth is described. Rapid growth of Listeria monocytogenes was shown to occur in liquid media with selectivity based on antibiotics found in Oxford agar. The final capacitance medium contained higher concentrations of the Oxford selective agents than Oxford agar and did not require the esculin/ferric ammonium citrate reaction to be observed. The medium relied upon the ability of Listeria spp. to induce a greater than 30% change in capacitance within 30 h. When run in parallel with the Listeria spp. test samples of a large food company, the method gave far fewer false-positive results than Fraser broth.


Assuntos
Técnicas Bacteriológicas , Microbiologia de Alimentos , Listeria/isolamento & purificação , Meios de Cultura , Condutividade Elétrica , Listeria/fisiologia , Fatores de Tempo
16.
J Food Prot ; 58(8): 934-936, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31137383

RESUMO

Survival of Lactobacillus bulgaricus during spray drying was studied at various outlet air temperatures. During spray drying the logarithmic survival ratio decreased with increased outlet air temperature with first-order kinetics; the pseudo-z value for Lactobacillus bulgaricus was 17.3°C. Plots of the death-rate constant for Lactobacillus bulgaricus versus reciprocal outlet temperature during spray drying in skim milk show a curve with two different activation energies (Ea). The calculated Ea values were 33.47 kJ/mol above 70°C and 85.77 kJ/mol below 70°C. Thermodynamic quantities for spray drying of Lactobacillus bulgaricus are also presented. Results show that the relationship between the entropy of activation and the enthalpy of activation for both spray drying and heating in liquid medium is linear, with all the data for drying falling in the range of a negative entropy.

19.
Br J Surg ; 78(10): 1181-4, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1958979

RESUMO

Fifty patients with gastro-oesophageal reflux disease refractory to multiple courses of medical therapy were entered into a prospective randomized trial comparing Nissen fundoplication with the Angelchick prosthesis as a primary surgical procedure. The two groups were matched for age, sex, duration of symptoms before surgery, type of medical therapy, pattern of symptom presentation, endoscopic grade of oesophageal inflammation, manometric lower oesophageal pressure and 24-h pH profile. Twenty-five patients were randomized to each of the Nissen fundoplication and Angelchik prosthesis groups. Operation time and hospital stay were similar in both groups. Persistent dysphagia was reported in five of the patients with an Angelchik prosthesis compared with none in the Nissen fundoplication group. Three prostheses were removed because of severe dysphagia while no Nissen fundoplication required revision. No patient with preoperative dysphagia because of stricture reported swallowing difficulties after operation. At clinical assessment at 3, 6, 12 and 24 months after operation, 85-88 per cent of the patients having a Nissen fundoplication were graded Visick 1 or 2 compared with 60-72 per cent of patients in the Angelchik group.


Assuntos
Fundo Gástrico/cirurgia , Refluxo Gastroesofágico/cirurgia , Próteses e Implantes , Adulto , Idoso , Transtornos de Deglutição/etiologia , Estenose Esofágica/etiologia , Esôfago/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Prognóstico , Estudos Prospectivos
20.
Ann R Coll Surg Engl ; 73(2): 131, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2018319
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