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1.
Am J Health Behav ; 45(2): 226-238, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33888184

RESUMO

Objectives: Our objective was to provide data contrasting commercial tobacco retailing in Tribal versus non-Tribal jurisdictions, in 3 states. These data may be relevant for US Food and Drug Administration regulation of Tribal retailing. Methods: With Tribal permission, observations were made on commercial tobacco advertising, product variety, pricing, and retail concept for stores within and just outside Tribal jurisdictions in areas of Arizona (AZ), California (CA), and Oklahoma (OK). Results: A total of 87 Tribal (20 AZ, 53 CA, 14 OK) and 67 (10, 43, 14) non-Tribal retailer visits were completed. There was substantial variation across tribes, with sales in AZ and most CA Tribal jurisdictions handled at convenience stores, whereas OK Tribal retailing was done mostly in specialized tobacco-specialty shops. Electronic cigarettes were ubiquitous across Tribal and non-Tribal outlets. Advertising and breadth of cigarette offerings was most extensive in the tobacco specialty retailers of Tribal OK. Surprisingly, Tribally manufactured cigarettes were found only at some CA Tribal retailers. Conclusions: Some Tribal commercial tobacco outlets actually price above their non-Tribal competitors and there is substantial variation in retailing strategy across Tribal jurisdictions. Tribal governments can continue to evaluate and reform commercial tobacco retailing so as to improve Tribal health.


Assuntos
Comércio , Sistemas Eletrônicos de Liberação de Nicotina , Produtos do Tabaco , Arizona , California , Humanos , Marketing , Oklahoma , Produtos do Tabaco/economia , Indígena Americano ou Nativo do Alasca
2.
Clin Exp Dermatol ; 45(6): 727-731, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32311113

RESUMO

Lichen planus pemphigoides (LPP) is a rare autoimmune subepidermal blistering disease characterized by the coexistence of both lichen planus and either bullous pemphigoid or mucous membrane pemphigoid (MMP) features. Frontal fibrosing alopecia (FFA) is a scarring alopecia, generally considered a form of lichen planopilaris. We report two patients with concomitant FFA and MPP. Patient 1 was a 73-year-old woman with the clinical and histological diagnosis of oral lichen planus. In addition, she presented alopecic plaques in the parietal area with blisters, immunohistologically compatible with Brunsting-Perry pemphigoid, a variant of MMP. During follow-up, the patient also developed FFA. Patient 2 was a 70-year-old woman with a history of ocular inflammation and desquamative gingivitis, who was diagnosed with MMP based on a conjunctival biopsy. She also had clinical features of FFA. ELISA and frontal biopsy confirmed the diagnoses of MMP and FFA. In conclusion, we report two patients with MMP associated with FFA, and discuss whether this association is a new variant of LPP or an incidental finding.


Assuntos
Alopecia/complicações , Líquen Plano/complicações , Doenças da Boca/patologia , Mucosa Bucal/patologia , Penfigoide Mucomembranoso Benigno/complicações , Idoso , Alopecia/patologia , Feminino , Gengivite/complicações , Humanos , Líquen Plano/patologia , Penfigoide Mucomembranoso Benigno/patologia , Couro Cabeludo/patologia
3.
Radiologe ; 57(11): 891-906, 2017 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-29046932

RESUMO

CLINICAL/METHODICAL ISSUE: Postoperative imaging of the ankle can be challenging, even for the experienced radiologist. Pathological and postoperative changes to the primarily complex anatomy of the ankle with its great variety of bone structures, tendons, ligaments, and soft tissue in a very limited space may cause great difficulty in differentiating underlying pathology from expected postoperative changes and artifacts, especially in magnetic resonance imaging (MRI). STANDARD RADIOLOGICAL METHODS: Selecting the appropriate radiological modality is key to making the correct diagnosis. Therefore, knowledge of the initial and current symptoms is just as important as familiarity with the most frequently performed operations in the ankle. PRACTICAL RECOMMENDATIONS: This article aims to give its reader a summary of the most important and frequently performed operation techniques of the ankle and discusses the expected appearance and possible complications in postoperative imaging.


Assuntos
Articulação do Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/cirurgia , Imageamento por Ressonância Magnética , Complicações Pós-Operatórias/diagnóstico por imagem , Traumatismos do Tornozelo/diagnóstico por imagem , Traumatismos do Tornozelo/cirurgia , Fixação Interna de Fraturas/instrumentação , Fraturas não Consolidadas/diagnóstico por imagem , Humanos
4.
Clin Exp Allergy ; 47(11): 1417-1425, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28865147

RESUMO

BACKGROUND: Targeting PD-1/PD-1 ligand signalling is an established treatment option for cancer. The role of these molecules in allergic asthma has been investigated in several mouse studies yielding conflicting results. However, human studies investigating the expression and regulation of PD-1 and its ligands in allergic inflammation are lacking. OBJECTIVE: To analyse the expression and regulation of PD-1 and its ligands in human allergic asthma. METHODS: The well-established human asthma model of segmental allergen challenge (SAC) was used to analyse the regulation of PD-1 and its ligands PD-L1 and PD-L2 on T lymphocytes and dendritic cells by flow cytometry. The impact of immunoglobulin E (IgE)-mediated signalling on PD-L1 expression was analysed on isolated plasmacytoid dendritic cells (pDCs). RESULTS: PD-1 expression by blood CD4+ T cells was negatively associated with total and specific (against the allergen used for provocation) IgE serum concentrations. Twenty-four hours after SAC, a small decrease in endobronchial PD-1+ CD4+ T cells was accompanied by an increase in PD-L1 expression on endobronchial myeloid dendritic cells (mDCs) and pDCs. The PD-L1 up-regulation on pDCs was not induced by IgE-mediated mechanisms. In contrast, PD-L2 was only detected on endobronchial mDCs and was significantly down-regulated 24 hours after SAC. CONCLUSION AND CLINICAL RELEVANCE: This study shows, for the first time, an association of a low PD-1 expression by circulating CD4+ T cells with high total and specific (against the allergen used for provocation) IgE concentrations in allergic asthma. In addition, we demonstrate a differential regulation of PD-1 ligands on endobronchial DCs after allergen challenge which may favour Th2 inflammation. Therefore, modulating PD-1 ligand-mediated pathways might be a promising target in allergic asthma.


Assuntos
Asma/imunologia , Asma/metabolismo , Imunomodulação , Receptor de Morte Celular Programada 1/metabolismo , Adulto , Alérgenos/imunologia , Asma/diagnóstico , Asma/tratamento farmacológico , Antígeno B7-H1/metabolismo , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Feminino , Expressão Gênica , Humanos , Imunoglobulina E/imunologia , Ligantes , Masculino , Pessoa de Meia-Idade , Receptores de IgE/metabolismo , Testes de Função Respiratória , Transdução de Sinais , Linfócitos T/imunologia , Linfócitos T/metabolismo , Adulto Jovem
5.
Radiologe ; 57(4): 309-326, 2017 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-28324121

RESUMO

Impingement syndrome of the ankle is a clinical diagnosis caused posttraumatically by overuse due to repetitive mechanical loading or the presence of predisposing anatomical variants. Ankle impingement syndrome is characterized by chronic pain and limited range of movement caused by mechanical compression of bony or soft tissues within the joint compartments. Ankle impingement syndrome is classified according to the various anatomical locations around the tibiotalar joint as anterior, anterolateral, anteromedial, posterior or posteromedial. Various imaging modalities are helpful in confirming the clinical diagnosis of ankle impingement. Radiography and computed tomography are used to identify bony abnormalities and intra-articular loose bodies. Magnetic resonance imaging is the modality of choice to demonstrate pathological soft tissue changes, bone marrow edema and osteochondral lesions. Dynamic sonography can identify the anatomical structures leading to impingement during movement.


Assuntos
Articulação do Tornozelo/diagnóstico por imagem , Artropatias/diagnóstico por imagem , Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/anormalidades , Humanos , Artropatias/etiologia , Imageamento por Ressonância Magnética , Síndrome , Tomografia Computadorizada por Raios X
6.
Phys Rev Lett ; 116(15): 157202, 2016 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-27127983

RESUMO

We study a charge two-channel Kondo model, demonstrating that recent experiments [Z. Iftikhar et al, Nature (London) 526, 233 (2015)] realize an essentially perfect quantum simulation-not just of its universal physics, but also nonuniversal effects away from the scaling limit. Numerical renormalization group (RG) calculations yield conductance line shapes encoding RG flow to a critical point involving a free Majorana fermion. By mimicking the experimental protocol, the experimental curve is reproduced quantitatively over 9 orders of magnitude, although we show that far greater bandwidth/temperature separation is required to obtain the universal result. Fermi liquid instabilities are also studied: In particular, our exact analytic results for nonlinear conductance provide predictions away from thermal equilibrium, in the regime of existing experiments.

7.
Am J Prev Med ; 48(1 Suppl 1): S111-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25528700

RESUMO

BACKGROUND: Oklahoma's tribal tobacco shops are distributed throughout the state, including in urban areas. During the time frame of this study, state excise tax rates for cigarettes varied by tribe and region, and took five distinct levels, ranging from 5.75 cents to $1.03 per pack. PURPOSE: To describe the pricing behavior of these smoke shops in a way that could support potential increases in the tribal taxation of cigarettes within the state. METHODS: Two waves (2010 and 2011) of site visits were conducted, covering nearly all tribal smoke shops in the northeastern quarter of the state, an area containing the city of Tulsa and 60% of all tribal outlets. Researchers recorded representative prices and verified the tax rate paid (via tax stamp) for each shop. Data were analyzed in 2013. RESULTS: Lower-taxed tribal cigarettes tended to be priced at discounts that were even greater than the differential in tax rates. For example, across waves, the average pack of Marlboros from a shop with a 5.75-cent tax stamp sold for 52 cents less than the same pack from a 25.75-cent shop and 60 cents less than from a 51.5-cent shop. The minimal inter-tribal price response to the discontinuation of large quantities of contraband cigarette sales suggests that inter-tribal price competition in the Tulsa area is not as intense as expected. CONCLUSIONS: Ample scope exists for either unilateral or coordinated cross-tribal tax and price increases that will increase tribal cigarette tax revenue collections and improve public health.


Assuntos
Indígenas Norte-Americanos , Impostos/economia , Produtos do Tabaco/economia , Comércio/economia , Comércio/estatística & dados numéricos , Competição Econômica , Humanos , Oklahoma
8.
Psychol Addict Behav ; 28(4): 1144-52, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24841185

RESUMO

Smokers who inhabit social contexts with a greater number of smokers may be exposed to more positive norms toward smoking and more cues to smoke. This study examines the relation between number of smoking friends and changes in number of smoking friends, and smoking cessation outcomes. Data were drawn from Wave 1 (2002) and Wave 2 (2003) of the International Tobacco Control (ITC) Project Four Country Survey, a longitudinal cohort survey of nationally representative samples of adult smokers in Australia, Canada, United Kingdom, and United States (N = 6,321). Smokers with fewer smoking friends at Wave 1 were more likely to intend to quit at Wave 1 and were more likely to succeed in their attempts to quit at Wave 2. Compared with smokers who experienced no change in their number of smoking friends, smokers who lost smoking friends were more likely to intend to quit at Wave 2, attempt to quit between Wave 1 and Wave 2, and succeed in their quit attempts at Wave 2. Smokers who inhabit social contexts with a greater number of smokers may be less likely to successfully quit. Quitting may be particularly unlikely among smokers who do not experience a loss in the number of smokers in their social context.


Assuntos
Amigos/psicologia , Intenção , Grupo Associado , Abandono do Hábito de Fumar/psicologia , Fumar/psicologia , Tabagismo/psicologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Austrália , Canadá , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Abandono do Hábito de Fumar/estatística & dados numéricos , Inquéritos e Questionários , Reino Unido , Estados Unidos , Adulto Jovem
9.
Nicotine Tob Res ; 15(10): 1663-72, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23509091

RESUMO

INTRODUCTION: Nearly all smokers in high-income Western countries report that they regret smoking (Fong, G. T., Hammond, D., Laux, F. L., Zanna, M. P., Cummings, M. K., Borland, R., & Ross, H. [2004]. The near-universal experience of regret among smokers in four countries: Findings from the International Tobacco Control Policy Evaluation Survey. Nicotine and Tobacco Research, 6, S341-S351. doi:10.1080/14622200412331320743), but no research to date has examined the prevalence of regret among smokers in non-Western, low- and middle-income countries. METHODS: Data were from the International Tobacco Control (ITC) Surveys of smokers in 4 Asian countries (China, Malaysia, South Korea, and Thailand); N = 9,738. Regret was measured with the statement: "If you had to do it over again, you would not have started smoking." RESULTS: Prevalence of regret in 3 countries (South Korea = 87%, Malaysia = 77%, and China = 74%) was lower than that found by Fong et al. in the United States, Australia, Canada, and the United Kingdom (89%-90%); but was higher in Thailand (93%). These significant country differences in regret corresponded with differences in tobacco control and norms regarding smoking. The predictors of regret in the Asian countries were very similar to those in the 4 Western countries: Regret was more likely to be experienced by smokers who smoked fewer cigarettes per day, perceived greater benefits of quitting and higher financial costs of smoking, had more prior quit attempts, worried that smoking would damage their health, and felt that their loved ones and society disapproved of smoking. Regret was also positively associated with intentions to quit (r = 0.23, p < .001). CONCLUSIONS: Across the Asian countries and high-income Western countries, the prevalence of regret varies, but the factors predicting regret are quite consistent. Regret may be an important indicator of tobacco control and is related to factors associated with future quitting.


Assuntos
Emoções/fisiologia , Abandono do Hábito de Fumar/psicologia , Fumar/psicologia , China , Comparação Transcultural , Feminino , Humanos , Intenção , Malásia , Masculino , República da Coreia , Fatores Socioeconômicos , Tailândia
10.
Phys Rev Lett ; 108(12): 126807, 2012 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-22540614

RESUMO

We investigate how a magnetic field induces one-dimensional edge channels when the two-dimensional surface states of three-dimensional topological insulators become gapped. The Hall effect, measured by contacting those channels, remains quantized even in situations where the θ term in the bulk and the associated surface Hall conductivities, σ(xy)(S), are not quantized due to the breaking of time-reversal symmetry. The quantization arises as the θ term changes by ±2πn along a loop around n edge channels. Model calculations show how an interplay of orbital and Zeeman effects leads to quantum Hall transitions, where channels get redistributed along the edges of the crystal. The network of edges opens new possibilities to investigate the coupling of edge channels.

11.
Br J Anaesth ; 106(6): 807-13, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21474477

RESUMO

BACKGROUND: Situation awareness (SA) is considered to be an important non-technical skill for delivering safe anaesthesia. The spatial distribution of visual attention (VA) is an underlying process for attaining adequate SA. In the present study, a novel technology was used to assess the distribution of VA in anaesthetists delivering anaesthesia. The impact of a critical incident on VA in relation to individual experience is analysed in a descriptive and exploratory manner. METHODS: Fifteen anaesthetists induced general anaesthesia in a full-scale simulator while wearing a head-mounted eye-tracking camera system. After an uneventful session, workload was increased in a randomized order by simulation of a critical incident in the second or third session. Eye tracking was used for the assessment of individual's distribution of VA to monitors, patient, and environment. A post hoc video analysis revealed information about the spatial distribution of VA. Descriptive statistics and exploratory analysis were used. RESULTS: Twenty per cent of VA was directed to the patient monitor (30% during critical incident scenarios, P=0.003). The more experienced anaesthetists (more than 2 yr of work experience) increased the amount of time dedicated to manual tasks from 21% to 25% during critical incidents, whereas the less experienced decreased from 20% to 14% (P=0.061). CONCLUSIONS: Distribution of attention is different during anaesthesia induction with critical incidents compared with uneventful anaesthesia induction. Less experienced anaesthesia providers spend more time on monitoring tasks. Further investigation in confirmatory designs is needed.


Assuntos
Anestesia Geral/normas , Atenção/fisiologia , Competência Clínica , Percepção Espacial/fisiologia , Anafilaxia/terapia , Conscientização/fisiologia , Métodos Epidemiológicos , Medições dos Movimentos Oculares , Feminino , Alemanha , Humanos , Complicações Intraoperatórias/terapia , Masculino , Monitorização Intraoperatória/normas , Simulação de Paciente , Desempenho Psicomotor , Análise e Desempenho de Tarefas , Carga de Trabalho
12.
Br J Anaesth ; 106(1): 44-50, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21037266

RESUMO

BACKGROUND: Workload assessment is an important tool for improving patient safety in anaesthesia. We tested the hypothesis that heart rate, pupil size, and duration of fixation increase, whereas saccade amplitude decreases with increased workload during simulated critical incidents. METHODS: Fifteen trainee anaesthetists participated in this randomized cross-over trial. Each participant used a head-mounted eye-tracking device (EyeSeeCam) during induction of general anaesthesia in a full-scale simulation during three different sessions. No critical incident was simulated in the first session. In a randomized order, workload was increased by simulation of a critical incident in the second or third session. Pupil size, duration of fixations, saccadic amplitude, and heart rate of each participant and the simulator conditions were recorded continuously and synchronized. The data were analysed by paired sample t-tests and mixed-effects regression analysis. RESULTS: The findings of the second and third sessions of 11 participants were analysed. Pupil diameter and heart rate increased simultaneously as the severity of the simulated critical incident increased. Allowing for individual effects, the simulator conditions explained 92.6% of the variance in pupil diameter and 93.6% of the variance in heart rate (both P<0.001). The duration of fixation decreased with increased workload. The saccadic amplitude remained unaffected by workload changes. CONCLUSIONS: Pupil size and heart rate reflect workload increase within simulator sessions, but they do not permit overall workload comparisons between individuals or sessions. Contrary to our assumption, the duration of fixation decreased with increased workload. Saccade amplitude did not reflect workload fluctuations.


Assuntos
Anestesia Geral , Movimentos Oculares/fisiologia , Corpo Clínico Hospitalar , Carga de Trabalho , Anafilaxia/terapia , Anestesiologia/educação , Simulação por Computador , Estudos Cross-Over , Educação de Pós-Graduação em Medicina/métodos , Medições dos Movimentos Oculares , Fixação Ocular , Frequência Cardíaca/fisiologia , Humanos , Simulação de Paciente , Projetos Piloto , Pupila/fisiologia , Movimentos Sacádicos
13.
Ann Oncol ; 20(9): 1560-1564, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19451183

RESUMO

The problem of inhalation of Aspergillus spores outside rooms with high-efficiency particulate air (HEPA) filtration has not been resolved as yet. Well-fitting masks are used in industrial and health care settings to protect from inhaling particles of 0.3-0.5 mum size. To investigate the efficacy and tolerability of well-fitting masks in high-risk patients, we conducted a prospective, randomised, multicentre study comparing standard hospital hygiene procedures with or without wearing masks in adults undergoing chemotherapy for acute leukaemia or allogeneic haematopoietic stem-cell transplantation (aHSCT). Forty-one patients were randomly assigned to wearing masks and 39 to the control group. In all, 76% of patients were treated in laminar airflow or HEPA-filtered rooms, 84% received oral polyenes, and three aHSCT recipients were given fluconazole. Duration of neutropenia was similar in both treatment groups. Invasive fungal infections were diagnosed in eight patients in either study arm. One patient in each arm died from proven invasive aspergillosis. There was no difference in the use of systemic antifungals. Of patients in the mask group, 65% described the comfort as acceptable, 26% as unpleasant, and 9% as intolerable. This first randomised study on the use of well-fitting masks failed to show a reduction of invasive fungal infections.


Assuntos
Hospedeiro Imunocomprometido , Aspergilose Pulmonar Invasiva/imunologia , Aspergilose Pulmonar Invasiva/prevenção & controle , Dispositivos de Proteção Respiratória , Adolescente , Adulto , Idoso , Antifúngicos/uso terapêutico , Antineoplásicos/efeitos adversos , Infecção Hospitalar/imunologia , Infecção Hospitalar/prevenção & controle , Feminino , Humanos , Aspergilose Pulmonar Invasiva/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Neutropenia/induzido quimicamente , Fatores de Risco , Adulto Jovem
15.
Radiology ; 244(1): 239-48, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17581904

RESUMO

PURPOSE: To retrospectively determine the frequency of posterior and anterior cystic abnormalities at rotator cuff insertion site on the greater tuberosity and to determine their relationship to patient age and rotator cuff disorders. MATERIALS AND METHODS: Institutional review board approval was given; informed consent was waived. The study was HIPAA compliant. In 238 patients with rotator cuff diagnoses at surgery, preoperative magnetic resonance (MR) imaging studies were reviewed to localize osseous cystic changes as anterior (supraspinatus insertion site) or posterior (infraspinatus insertion site) on the greater tuberosity. If rotator cuff tear was present, tendon retraction and location of partial tear (articular or bursal surface) were recorded. Two radiologists reached conclusions by consensus. Locations of cysts were correlated to surgical cuff diagnoses: no tear, tendinopathy, partial-thickness tear, and complete tear. Prospective interpretations from original MR reports were compared with surgical results. Statistical analyses included one-way analysis of variance, chi(2), Fisher exact, and Student t tests, as well as logistic regression and receiver operating characteristic curve comparison. RESULTS: There were 238 consecutive patients (150 men, 88 women; mean age, 43 years). Cysts were located at or near footprint of cuff tendon and demonstrated fluid or soft-tissue signal intensities. Posterior cysts occurred in 56.7% of shoulders and showed no statistical correlation to age or cuff diagnosis. Anterior cysts occurred in 22.7% of shoulders and were strongly associated with cuff disorders (P<.001). Controlling for cuff disorders, there was no relationship between anterior cysts and age (P>.50). Anterior cysts were more common in partial-thickness articular (48%) than in bursal (13%) tears (P<.001). CONCLUSION: Posterior cysts were more common than anterior cysts and showed nearly random distribution among patients, regardless of age and cuff diagnosis. Anterior cysts were closely associated with cuff disorders.


Assuntos
Cistos/patologia , Imageamento por Ressonância Magnética/métodos , Manguito Rotador/patologia , Tendões/patologia , Adulto , Fatores Etários , Análise de Variância , Distribuição de Qui-Quadrado , Meios de Contraste , Feminino , Gadolínio DTPA , Humanos , Masculino , Estudos Retrospectivos , Lesões do Manguito Rotador , Lesões do Ombro , Articulação do Ombro/patologia
16.
Methods Inf Med ; 46(3): 270-4, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17492111

RESUMO

OBJECTIVE: Volume segmentation with concurrent visualization is becoming an increasingly important part of medical diagnostics. This is due to the fact that the immediate visual feedback speeds up evaluation of the segmentation process, hence enhances segmentation quality. Therefore, our aim was to develop a method for volume segmentation and smoothing which achieves interactive performance on standard PCs and is useful in clinical practice (i.e. fast and of high quality). METHODS: Our application is based on seeded region growing and nonlinear isotropic as well as anisotropic diffusion. We use current GPUs (graphics processing units) to speed up the computation of the diffusion process and use hardware-accelerated interactive volume rendering. RESULTS: Using our approach the user can observe the diffusion process in real-time, change parameters interactively and view the result in a high-quality 3D direct volume rendering (DVR). CONCLUSION: The interactive nature of our algorithm and simultaneous visualization improved the usability of our segmentation and smoothing algorithm and proved useful in the clinical workflow. Using our application we were able to speed up the (an)isotropic diffusion process to achieve interactive performance.


Assuntos
Gráficos por Computador , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional , Interface Usuário-Computador , Áustria
17.
Radiology ; 243(1): 171-9, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17312278

RESUMO

PURPOSE: To prospectively evaluate the effectiveness of portal vein embolization (PVE) and CD133(+) bone marrow stem cell (BMSC) administration to the liver, compared with PVE alone, to augment hepatic regeneration in patients with large hepatic malignancies. MATERIALS AND METHODS: The study was approved by the institutional ethics committee; informed consent was obtained. Thirteen patients underwent PVE of liver segments I and IV-VIII to stimulate hepatic regeneration prior to extended right hepatectomy. In six patients (three men, three women; mean age, 61 years; range, 46-72 years) with a future liver remnant volume (FLRV) below 25% and/or limited quality of hepatic parenchyma, PVE alone did not promise adequate proliferation. These patients underwent BMSC administration to segments II and III (group I). In seven patients (three men, four women; mean age, 69 years; range, 63-75 years) with an FLRV below 25%, PVE alone was performed (group II). Two radiologists blinded to patients' identity and each other's results measured liver and tumor volumes with helical computed tomography. Absolute, relative, and daily FLRV gains were compared by using the t test or the Wilcoxon test. RESULTS: The increase of the mean absolute FLRV in group I from 239.3 mL +/- 103.5 (standard deviation) to 417.1 mL +/- 150.4 was significantly higher than that from 286.3 mL +/- 77.1 to 395.9 mL +/- 94.1 in group II (P = .049). The relative gain of FLRV after PVE in group I (77.3% +/- 38.2) was significantly higher than that in group II (39.1% +/- 20.4) (P = .039). The daily hepatic growth rate in group I (9.5 mL/d +/- 4.3) was significantly superior to that in group II (4.1 mL/d +/- 1.9) (P = .03). Time to surgery was 27 days +/- 11 in group I and 45 days +/- 21 in group II (P = .057). CONCLUSION: In patients with malignant liver lesions, the combination of PVE with CD133(+) BMSC administration substantially increased hepatic regeneration compared with PVE alone.


Assuntos
Antígenos CD , Carcinoma Hepatocelular/terapia , Colangiocarcinoma/terapia , Embolização Terapêutica , Glicoproteínas , Transplante de Células-Tronco Hematopoéticas , Neoplasias Hepáticas/terapia , Fígado/fisiologia , Peptídeos , Regeneração , Antígeno AC133 , Idoso , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Bilirrubina/sangue , Carcinoma Hepatocelular/diagnóstico por imagem , Neoplasias Colorretais/patologia , Feminino , Células-Tronco Hematopoéticas/imunologia , Humanos , Coeficiente Internacional Normatizado , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Veia Porta , Cuidados Pré-Operatórios , Tomografia Computadorizada por Raios X , Transplante Autólogo
18.
Ecol Appl ; 17(8): 2214-32, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18213964

RESUMO

Since the mid-1970s, the western Steller sea lion (Eumetopias jubatus), inhabiting Alaskan waters from Prince William Sound west through the Aleutian Islands, has declined by over 80%. Changing oceanographic conditions, competition from fishing operations, direct human-related mortality, and predators have been suggested as factors driving the decline, but the indirect and interactive nature of their effects on sea lions have made it difficult to attribute changes in abundance to specific factors. In part, this is because only changes in abundance, not changes in vital rates, are known. To determine how vital rates of the western Steller sea lion have changed during its 28-year decline, we first estimated the changes in Steller sea lion age structure using measurements of animals in aerial photographs taken during population surveys since 1985 in the central Gulf of Alaska (CGOA). We then fit an age-structured model with temporally varying vital rates to the age-structure data and to total population and pup counts. The model fits indicate that birth rate in the CGOA steadily declined from 1976 to 2004. Over the same period, survivorship first dropped severely in the early 1980s, when the population collapsed, and then survivorship steadily recovered. The best-fitting model indicates that in 2004, the birth rate in the central Gulf of Alaska was 36% lower than in the 1970s, while adult and juvenile survivorship were close to or slightly above 1970s levels. These predictions and other model predictions concerning population structure match independent field data from mark-recapture studies and photometric analyses. The dominant eigenvalue for the estimated 2004 Leslie matrix is 1.0014, indicating a stable population. The stability, however, depends on very high adult survival, and the shift in vital rates results in a population that is more sensitive to changes in adult survivorship. Although our modeling analysis focused exclusively on the central Gulf of Alaska, the western Gulf of Alaska and eastern Aleutians show a similar pattern of declining pup fraction with no increase in the juvenile, or pre-breeding, fraction. This suggests that declining birth rate may be a problem for western Steller sea lions across the Gulf of Alaska and into the Aleutian Islands.


Assuntos
Modelos Biológicos , Leões-Marinhos/fisiologia , Distribuição por Idade , Alaska , Animais , Conservação dos Recursos Naturais , Monitoramento Ambiental , Feminino , Masculino , Dinâmica Populacional , Fatores de Tempo
19.
Oecologia ; 144(4): 607-17, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15891836

RESUMO

We used feathers of known origin collected from across the breeding range of a migratory shorebird to test the use of isotope tracers for assigning breeding origins. We analyzed deltaD, delta13C, and delta15N in feathers from 75 mountain plover (Charadrius montanus) chicks sampled in 2001 and from 119 chicks sampled in 2002. We estimated parameters for continuous-response inverse regression models and for discrete-response Bayesian probability models from data for each year independently. We evaluated model predictions with both the training data and by using the alternate year as an independent test dataset. Our results provide weak support for modeling latitude and isotope values as monotonic functions of one another, especially when data are pooled over known sources of variation such as sample year or location. We were unable to make even qualitative statements, such as north versus south, about the likely origin of birds using both deltaD and delta13C in inverse regression models; results were no better than random assignment. Probability models provided better results and a more natural framework for the problem. Correct assignment rates were highest when considering all three isotopes in the probability framework, but the use of even a single isotope was better than random assignment. The method appears relatively robust to temporal effects and is most sensitive to the isotope discrimination gradients over which samples are taken. We offer that the problem of using isotope tracers to infer geographic origin is best framed as one of assignment, rather than prediction.


Assuntos
Migração Animal/fisiologia , Isótopos de Carbono/metabolismo , Charadriiformes/metabolismo , Plumas/química , Isótopos de Nitrogênio/metabolismo , Animais , Demografia , Modelos Biológicos , Fatores de Tempo
20.
Nicotine Tob Res ; 6 Suppl 3: S341-51, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15799597

RESUMO

Regret may be a key variable in understanding the experience of smokers, the vast majority of whom continue to smoke while desiring to quit. We present data from the baseline wave (October-December 2002) of the International Tobacco Control Policy Evaluation Survey, a random-digit-dialed telephone survey of a cohort of over 8,000 adult smokers across four countries--Canada, the United States, the United Kingdom, and Australia--to estimate the prevalence of regret and to identify its predictors. The proportion of smokers who agreed or agreed strongly with the statement "If you had to do it over again, you would not have started smoking" was extremely high--about 90%--and nearly identical across the four countries. Regret was more likely to be experienced by older smokers, women, those who had tried to quit more often, those who perceived quitting as conferring benefits, those with higher levels of perceived addiction, those who worried about future damage to health, those who perceived smoking as lowering their quality of life, those who perceived higher monetary costs of smoking, and those who believed that smoking is not socially acceptable. This predictive model was the same in all four countries. Regret is thus a near-universal experience among smokers in all four countries, and the factors that predict regret are universal across these four countries. Among other implications for cessation treatment and smoking prevention, this near universality of regret casts doubt on the view of some policy analysts and economists that the decisions to take up and continue smoking are welfare-maximizing for the consumer.


Assuntos
Comportamento Aditivo/psicologia , Culpa , Conhecimentos, Atitudes e Prática em Saúde , Abandono do Hábito de Fumar/psicologia , Fumar/psicologia , Tabagismo/psicologia , Adulto , Austrália/epidemiologia , Canadá/epidemiologia , Feminino , Educação em Saúde/métodos , Promoção da Saúde/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Nicotina/efeitos adversos , Prevalência , Fatores de Risco , Fumar/epidemiologia , Abandono do Hábito de Fumar/métodos , Fatores Socioeconômicos , Inquéritos e Questionários , Fatores de Tempo , Tabagismo/epidemiologia , Reino Unido/epidemiologia , Estados Unidos/epidemiologia
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