Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 53
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Langenbecks Arch Surg ; 402(1): 159-165, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27686086

RESUMO

BACKGROUND: During the initial assessment of patients with potential severe injuries, radiological examinations are performed in order to rapidly diagnose clinically relevant injuries. Previous studies have shown that performing these examinations routinely is not always necessary and that trauma patients are exposed to substantial radiation doses. The aim of this study was to assess the amount and findings of radiological examinations during the initial assessment of trauma patients and to determine the radiation doses to which these patients are exposed to. METHODS: We analyzed the 1124 patients included in a randomized trial. All radiological examinations during the initial assessment (i.e., primary and secondary survey) were assessed. The examination results were categorized as positive findings (i.e., (suspicion for) traumatic injury) and normal findings. The effective radiation doses for the examinations were calculated separately for each patient. RESULTS: Eight hundred and three patients were male (71 %), median age was 38 years, and 1079 patients sustained blunt trauma (96 %). During initial assessment, almost 3900 X-rays were performed, of which 25.4 % showed positive findings. FAST of the abdomen was performed in 989 patients (88 %), with positive findings in 10.6 %. Additional CT scanning of specific body regions was performed 1890 times in 813 patients (72.1 %), of which approximately 43.4 % revealed positive findings. Hemodynamically stable patients showed more normal findings on the radiographic studies than unstable patients. The mean radiation doses for the total population was 8.46 mSv (±7.7) and for polytraumatized patients (ISS ≥ 16) 14.3 mSv (±9.5). CONCLUSION: Radiological diagnostics during initial assessment of trauma patients show a high rate of normal findings in our trauma system. The radiation doses to which trauma patients are exposed are considerable. Considering that the majority of the injured patients are hemodynamically stable, we suggest more selective use of X-ray and CT scanning.


Assuntos
Exposição à Radiação , Ferimentos e Lesões/diagnóstico por imagem , Adulto , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Tomografia Computadorizada por Raios X , Centros de Traumatologia
2.
Eur Radiol ; 23(1): 148-55, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22886533

RESUMO

OBJECTIVE: To determine the cost-effectiveness of trauma room CT compared with CT performed at the radiology department. METHODS: In this randomised controlled trial, adult patients requiring evaluation in a level 1 trauma centre were included. In the intervention hospital the CT system was located within the trauma room and in the control hospital within the radiology department. Direct and indirect medical costs of the institutionalised stay and diagnostic and therapeutic procedures were calculated. RESULTS: A total of 1,124 patients were randomised with comparable demographic characteristics. Mean number of non-institutionalised days alive was 322.5 in the intervention group (95 % CI 314-331) and 320.7 in the control group (95 % CI 312.1-329.2). Mean costs of diagnostic and therapeutic procedures per hospital inpatient day were 554 for the intervention group and 468 for the control group. Total mean costs in the intervention group were 16,002 (95 % CI 13,075-18,929) and 16,635 (95 % CI 13,528-19,743) for the control group (P = 0.77). CONCLUSION: The present study showed that in trauma patients the setting with a CT system located in the trauma room did not provide any advantages or disadvantages from a health economics perspective over a CT system located in the radiology department.


Assuntos
Serviço Hospitalar de Radiologia/economia , Tomografia Computadorizada por Raios X/economia , Centros de Traumatologia/economia , Adulto , Análise Custo-Benefício , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estatísticas não Paramétricas
3.
Br J Surg ; 99 Suppl 1: 105-13, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22441863

RESUMO

BACKGROUND: Computed tomography (CT) of injured patients in the radiology department requires potentially dangerous and time-consuming patient transports and transfers. It was hypothesized that CT in the trauma room would improve patient outcome and workflow. METHODS: A randomized trial compared the effect of locating a CT scanner in the trauma room versus the radiology department in two Dutch trauma hospitals. Injured patients aged at least 16 years were assigned randomly to one of these hospitals at the time of transport. The primary outcome measure was the number of non-institutionalized days within the first year after randomization. Subgroup analyses were performed in patients with multiple trauma or severe traumatic brain injury (TBI). RESULTS: Some 1124 patients were included, of whom 1045 were available for analysis. The median number of non-institutionalized days was 360 days in the intervention group versus 362 days for the control group (P = 0.068). The time from arrival to the first CT imaging was 13 min shorter in the intervention group (36 versus 49 min; P < 0.001). Patient transfers and transports were reduced by more than half in the intervention group. For both multiple trauma (265 patients) and TBI (121) subgroups, differences in mortality and out-of-hospital days favoured the intervention group, but were not statistically significant. CONCLUSION: A CT scanner located in the trauma room reduces the time to acquire CT images and improves workflow, but does not lead to substantial improvements in clinical outcomes in a general trauma population. Observed beneficial effects on outcomes in patients with multiple trauma or severe TBI were not statistically significant. REGISTRATION NUMBER: ISRCTN55332315 (http://www.controlled-trials.com).


Assuntos
Serviço Hospitalar de Radiologia , Tomografia Computadorizada por Raios X/métodos , Centros de Traumatologia , Ferimentos e Lesões/diagnóstico por imagem , Adulto , Cuidados Críticos/estatística & dados numéricos , Feminino , Humanos , Escala de Gravidade do Ferimento , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Fatores de Tempo , Tomografia Computadorizada por Raios X/mortalidade , Resultado do Tratamento , Ferimentos e Lesões/mortalidade
4.
Eur Spine J ; 17(8): 1096-100, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18575897

RESUMO

The Roland Morris Disability Questionnaire (RMDQ-24) and the VAS spine score have been regularly used to measure functional outcome in patients with back pain. The RMDQ-24 is primarily used in degenerative disease of the spine and the VAS Spine is used in trauma patients. The aim of this study is to compare these scores and to see if there is a correlation in patients with a traumatic thoracolumbar spinal fracture. Prospective cohort study comparing the RMDQ-24 and the VAS spine score in patients with a traumatic type A fracture thoracolumbar spine fracture. Fifteen non-operatively patients (group one) completed 118 questionnaires and 17 operatively treated patients (group two) completed 140 questionnaires. Group one scored an average of 6.6 and 65.9 for the RMDQ-24 and VAS Spine, in group two this was 5.1 and 82.9. Spearman's correlation test showed a significant correlation, in group one 0.83 and for the second group 0.87. RMDQ-24 and VAS Spine have a strong positive correlation in measuring disability in a group of patients with back pain because of a spinal fracture. In both non-operatively and operatively treated groups this correlation is significant.


Assuntos
Dor nas Costas/etiologia , Avaliação da Deficiência , Medição da Dor , Fraturas da Coluna Vertebral/complicações , Fraturas da Coluna Vertebral/terapia , Atividades Cotidianas , Adolescente , Adulto , Dor nas Costas/epidemiologia , Estudos de Coortes , Feminino , Humanos , Vértebras Lombares , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recuperação de Função Fisiológica , Inquéritos e Questionários , Vértebras Torácicas , Resultado do Tratamento
5.
J Bone Joint Surg Am ; 87(11): 2464-71, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16264122

RESUMO

BACKGROUND: A variety of diagnostic imaging techniques is available for excluding or confirming chronic osteomyelitis. Until now, an evidence-based algorithmic model for choosing the most suitable imaging technique has been lacking. The objective of this study was to determine the accuracy of current imaging modalities in the diagnosis of chronic osteomyelitis. METHODS: A systematic review and meta-analysis of the literature was conducted with a comprehensive search of the MEDLINE, EMBASE, and Current Contents databases to identify clinical studies on chronic osteomyelitis that evaluated diagnostic imaging modalities. The value of each imaging technique was studied by determining its sensitivity and specificity compared with the results of histological analysis, findings on culture, and clinical follow-up of more than six months. RESULTS: A total of twenty-three clinical studies in which the accuracy was described for radiography (two studies), magnetic resonance imaging (five), computed tomography (one), bone scintigraphy (seven), leukocyte scintigraphy (thirteen), gallium scintigraphy (one), combined bone and leukocyte scintigraphy (six), combined bone and gallium scintigraphy (three), and fluorodeoxyglucose positron emission tomography (four) were included in the review. No meta-analysis was performed with respect to computed tomography, gallium scintigraphy, and radiography. Pooled sensitivity demonstrated that fluorodeoxyglucose positron emission tomography was the most sensitive technique, with a sensitivity of 96% (95% confidence interval, 88% to 99%) compared with 82% (95% confidence interval, 70% to 89%) for bone scintigraphy, 61% (95% confidence interval, 43% to 76%) for leukocyte scintigraphy, 78% (95% confidence interval, 72% to 83%) for combined bone and leukocyte scintigraphy, and 84% (95% confidence interval, 69% to 92%) for magnetic resonance imaging. Pooled specificity demonstrated that bone scintigraphy had the lowest specificity, with a specificity of 25% (95% confidence interval, 16% to 36%) compared with 60% (95% confidence interval, 38% to 78%) for magnetic resonance imaging, 77% (95% confidence interval, 63% to 87%) for leukocyte scintigraphy, 84% (95% confidence interval, 75% to 90%) for combined bone and leukocyte scintigraphy, and 91% (95% confidence interval, 81% to 95%) for fluorodeoxyglucose positron emission tomography. The sensitivity of leukocyte scintigraphy in detecting chronic osteomyelitis in the peripheral skeleton was 84% (95% confidence interval, 72% to 91%) compared with 21% (95% confidence interval, 11% to 38%) for its detection of chronic osteomyelitis in the axial skeleton. The specificity of leukocyte scintigraphy in the axial skeleton was 60% (95% confidence interval, 39% to 78%) compared with 80% (95% confidence interval, 61% to 91%) for the peripheral skeleton. CONCLUSIONS: Fluorodeoxyglucose positron emission tomography has the highest diagnostic accuracy for confirming or excluding the diagnosis of chronic osteomyelitis. Leukocyte scintigraphy has an appropriate diagnostic accuracy in the peripheral skeleton, but fluorodeoxyglucose positron emission tomography is superior for detecting chronic osteomyelitis in the axial skeleton.


Assuntos
Osteomielite/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Doença Crônica , Fluordesoxiglucose F18 , Humanos , Osteomielite/diagnóstico , Cintilografia/métodos , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
J Bone Joint Surg Am ; 87(6): 1367-78, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15930551

RESUMO

The discovery of bone morphogenetic proteins marks a major step forward in the understanding of bone physiology and in the development of advanced methods in skeletal surgery. The cornerstones for successful growth-factor therapy in skeletal surgery remain biomechanical stability and biological vitality of the bone providing an adequate environment for new bone formation. Knowledge of the biological characteristics, mechanisms of action, and methods of delivery of growth factors will become essential for skeletal surgeons. The current clinical application of bone morphogenetic proteins is safe and efficacious as a result of a well-regulated cascade of events leading to bone formation. Clinical trials have not yet determined whether different clinical indications each require a specific bone-tissue-engineering format or if a single pathway for stimulating bone-healing with growth factors is sufficient.


Assuntos
Proteínas Morfogenéticas Ósseas/uso terapêutico , Fraturas Ósseas/terapia , Animais , Proteínas Morfogenéticas Ósseas/administração & dosagem , Proteínas Morfogenéticas Ósseas/fisiologia , Diferenciação Celular/fisiologia , Proteínas de Ligação a DNA/fisiologia , Consolidação da Fratura/efeitos dos fármacos , Consolidação da Fratura/fisiologia , Fraturas Ósseas/fisiopatologia , Terapia Genética , Humanos , Osteogênese/fisiologia , Transdução de Sinais/fisiologia , Proteínas Smad , Transativadores/fisiologia , Fator de Crescimento Transformador beta/fisiologia
7.
Bone ; 31(1): 158-64, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12110429

RESUMO

Osteogenic protein-1 (OP-1), or bone morphogenetic protein-7, is an osteoinductive morphogen that is involved in embryonic skeletogenesis and in bone repair. In bone defect models without spontaneous healing, local administration of recombinant human OP-1 (rhOP-1) induces complete healing. To investigate the ability of rhOP-1 to accelerate normal physiologic fracture healing, an experimental study was performed. In 40 adult female goats a closed tibial fracture was made, stabilized with an external fixator, and treated as follows: (1) no injection; (2) injection of 1 mg rhOP-1 dissolved in aqueous buffer; (3) injection of collagen matrix; and (4) injection of 1 mg rhOP-1 bound to collagen matrix. The test substances were injected in the fracture gap under fluoroscopic control. At 2 and 4 weeks, fracture healing was evaluated with radiographs, three-dimensional computed tomography (CT), dual-energy X-ray absorptiometry, biomechanical tests, and histology. At 2 weeks, callus diameter, callus volume, and bone mineral content at the fracture site were significantly increased in both rhOP-1 groups compared with the no-injection group. As signs of accelerated callus maturation, bending and torsional stiffness were higher and bony bridging of the fracture gap was observed more often in the group with rhOP-1 dissolved in aqueous buffer than in uninjected fractures. Treatment with rhOP-1 plus collagen matrix did not result in improved biomechanical properties or bony bridging of the fracture gap at 2 weeks. At 4 weeks there were no differences between groups, except for a larger callus volume in the rhOP-1 plus collagen matrix group compared with the control groups. All fractures showed an advanced stage of healing at 4 weeks. In conclusion, the healing of a closed fracture in a goat model can be accelerated by a single local administration of rhOP-1. The use of a carrier material does not seem to be crucial in this application of rhOP-1.


Assuntos
Proteínas Morfogenéticas Ósseas/uso terapêutico , Proteínas Recombinantes/uso terapêutico , Fraturas da Tíbia/tratamento farmacológico , Fator de Crescimento Transformador beta , Absorciometria de Fóton/métodos , Animais , Proteína Morfogenética Óssea 7 , Diáfises/diagnóstico por imagem , Diáfises/lesões , Feminino , Cabras , Humanos , Fraturas da Tíbia/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos
8.
Biomaterials ; 22(7): 725-30, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11246967

RESUMO

Fracture healing could be stimulated with osteoinductive bone morphogenetic proteins (bmp's), such as osteogenic protein-1 (OP-1), but little is known about its effectiveness in stimulation of fracture healing. In this study, biomechanical and histological aspects of fracture healing after an injection of OP-1 in the fracture gap were investigated. In 40 goats, a closed fracture was created in the left tibia. The fractures were stabilized with an external fixator and the animals were assigned to four different groups: no injection, injection of 1 mg OP-1, injection of 1 mg OP-1 with collagenous carrier material, and injection of carrier material alone. Twenty-one animals were sacrificed after 2 weeks and 19 after 4 weeks. Biomechanical testing was perfomed on both explanted tibiae. Four longitudinal samples of the fracture were sawn, processed for histology, and examined by two observers. Biomechanical evaluation showed a higher stiffness and strength at 2 weeks after injection of OP-1. Histological evaluation showed normal fracture healing patterns in all animals without adverse effects of the given injections. These data show that fracture healing can be accelerated with a single injection of OP-1, eventually resulting in normally healed bone.


Assuntos
Proteínas Morfogenéticas Ósseas/farmacologia , Consolidação da Fratura/efeitos dos fármacos , Consolidação da Fratura/fisiologia , Fator de Crescimento Transformador beta , Animais , Fenômenos Biomecânicos , Proteína Morfogenética Óssea 7 , Proteínas Morfogenéticas Ósseas/administração & dosagem , Colágeno/metabolismo , Feminino , Fixação de Fratura , Cabras , Fraturas da Tíbia/patologia , Fraturas da Tíbia/fisiopatologia , Fraturas da Tíbia/terapia
9.
Surgery ; 103(4): 477-80, 1988 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3353859

RESUMO

In 17% to 74% of patients with subclavian vein thrombosis, conservative treatment or venous thrombectomy led to residual symptoms. To improve these results, a prospective study was started in patients with subclavian vein thrombosis who were treated with a combined approach of local thrombolytic therapy followed by a first-rib resection. From 1983 to 1987 five patients entered the protocol. Total lysis was achieved in all cases. In the follow-up period, phlebography and strain-gauge plethysmography according to Whitney showed no recurrent thrombosis. All patients were able to resume their normal activities.


Assuntos
Costelas/cirurgia , Estreptoquinase/administração & dosagem , Veia Subclávia , Trombose/terapia , Adulto , Cateterismo , Feminino , Seguimentos , Heparina/administração & dosagem , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Flebografia , Pletismografia , Estudos Prospectivos , Trombose/diagnóstico , Trombose/diagnóstico por imagem
10.
Surgery ; 106(1): 21-5, 1989 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2662462

RESUMO

Intermittent claudication and limb-threatening ischemia caused by occlusion of large and medium-sized arteries are rare manifestations of systemic lupus erythematosus. So far only eight documented cases have been reported, predominantly in young women. In this report two more patients are described. There is no common opinion concerning pathophysiologic mechanism, but immunologic endothelial damage and circulating antibodies to phospholipid probably play a role. The results of medical and surgical treatment are disappointing, and amputation becomes necessary in more than half of the patients.


Assuntos
Claudicação Intermitente/etiologia , Isquemia/etiologia , Lúpus Eritematoso Sistêmico/complicações , Adulto , Feminino , Humanos , Claudicação Intermitente/fisiopatologia , Isquemia/fisiopatologia , Lúpus Eritematoso Sistêmico/fisiopatologia , Trombose/etiologia , Trombose/cirurgia
11.
J Appl Physiol (1985) ; 77(5): 2311-7, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7868450

RESUMO

A longitudinal analysis of a group of speed skaters was done to identify the performance-determining factors for a successful speed skating career. This paper presents both the physiological and anthropometric results of this longitudinal study. Twenty-four athletes from the Dutch National Junior Speed Skating Team were followed from age 16-17 yr to age 20-21 yr. During the development from junior to senior speed skater, a number of anthropometric and physiological variables changed. There were no differences between successful and unsuccessful speed skaters from an anthropometric perspective; consequently, it was not possible to distinguish successful from unsuccessful athletes on anthropometric grounds. The longitudinal data showed that at a younger age the successful speed skaters had similar oxygen consumption, mechanical efficiency, and power output values compared with the unsuccessful speed skaters. Later in the study, successful speed skaters distinguished themselves by the ability to produce higher power output values. There were no anthropometric or physiological relationships found in this study on which performance at the age of 20-21 yr could be predicted with measurements at a junior age.


Assuntos
Resistência Física/fisiologia , Patinação , Adolescente , Adulto , Envelhecimento , Antropometria , Gasometria , Constituição Corporal , Teste de Esforço , Feminino , Humanos , Estudos Longitudinais , Masculino , Consumo de Oxigênio , Mecânica Respiratória , Caracteres Sexuais
12.
J Neurol ; 247(9): 669-76, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11081804

RESUMO

We present a systematic review of the literature on the prevalence, nature, severity, course, and causes of cognitive deficits in patients with occlusive disease of the carotid artery prior to surgery (if surgery was under discussion). Searches were carried out on Medline and Psychlit from 1980 to 1999 using neurovascular and psychological index terms, and papers and books were checked for further references. Studies describing neuropsychological assessment of groups of patients with carotid obstruction were included. Eighteen studies were found. We extracted from the papers data on study design, demographic characteristics of patients, clinical diagnosis, carotid obstruction, cerebral imaging, time interval between ischemic episode and neuropsychological assessment, neuropsychological assessment procedures, integration and interpretation of test performances, and conclusions of authors. Fourteen studies concluded that there are cognitive deficits both in patients with symptomatic and in those with asymptomatic carotid obstruction; four studies denied cognitive impairment. There were no differences in patient characteristics, study design, or neuropsychological assessment procedures between the 14 studies that found deficits and the 4 that did not. There are indications for a mild, diffuse detrimental effect of carotid occlusive disease on cognitive functioning. However, methodological problems prevent a definitive conclusion. Further research is needed to confirm these findings and to ascertain the neurovascular risk factors for and the natural course of cognitive impairment in patients with carotid occlusive disease.


Assuntos
Doenças das Artérias Carótidas/complicações , Transtornos Cognitivos/etiologia , Adulto , Idoso , Doenças das Artérias Carótidas/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Reprodutibilidade dos Testes , Fatores de Risco
13.
J Orthop Res ; 17(5): 654-60, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10569473

RESUMO

An appropriate animal model is required for the study of treatments that enhance bone healing. A new segmental long bone defect model was developed for this purpose, and dual energy x-ray absorptiometry was used to quantify healing of this bone defect. In 15 sheep, a 3-cm segmental defect was created in the left tibia and fixed with an interlocking intramedullary nail. In seven animals, the defect was left empty for the assessment of the spontaneous healing response. In eight animals serving as a positive control, autologous bone grafting was performed. After 12 weeks, healing was evaluated with radiographs, a torsional test to failure, and dual energy x-ray absorptiometry. The mechanical test results were used for the assessment of unions and nonunions. Radiographic determination of nonunion was not reliably accomplished in this model. By means of dual energy x-ray absorptiometry, bone mineral density and content were measured in the middle of the defect. Bone mineral density was 91+/-7% (mean +/- SEM) and 72+/-6% that of the contralateral intact tibia in, respectively, the autologous bone-grafting and empty defect groups (p = 0.04). For bone mineral content, the values were, respectively, 117+/-18 and 82+/-9% (p = 0.07). Torsional strength and stiffness were also higher, although not significantly, in the group with autologous bone grafting than in that with the empty defect. Bone mineral density and content were closely related to the torsional properties (r2 ranged from 0.76 to 0.85, p < or = 0.0001). Because interlocking intramedullary nailing is a very common fixation method in patients, the newly developed segmental defect model has clinical relevance. The interlocking intramedullary nail provided adequate stability without implant failure. This model may be useful for the study of treatments that affect bone healing, and dual energy x-ray absorptiometry may be somewhat helpful in the analysis of healing of this bone defect.


Assuntos
Densidade Óssea , Modelos Animais de Doenças , Ovinos , Fraturas da Tíbia/fisiopatologia , Cicatrização/fisiologia , Absorciometria de Fóton , Animais , Fenômenos Biomecânicos , Feminino , Análise de Regressão , Instrumentos Cirúrgicos , Fraturas da Tíbia/diagnóstico por imagem , Anormalidade Torcional
14.
J Exp Psychol Hum Percept Perform ; 20(3): 591-612, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8027714

RESUMO

Information specifying the future passing distance of an approaching object is available (in units of object size) in the ratio of optical displacement velocity and optical expansion velocity. Despite empirical support for the assumption that object size can serve as a metric in the perception of passing distance, the present series of experiments reveals that in catching a ball subjects do not rely on such "point-predictive" information. The angle at which (real and simulated) balls approached the subject systematically affected verbal and manual estimates of future passing distance, as well as the kinematic characteristics of catching movements. To catch a ball, the actor uses momentary action-related information instead of spatiotemporal estimates. The hand velocity is geared to information specifying the currently required velocity. This secures ending up at the right place in the right time, regardless of where this may be.


Assuntos
Percepção de Distância , Mãos , Percepção de Movimento , Movimento , Percepção do Tempo , Adulto , Feminino , Humanos , Masculino , Estimulação Luminosa , Percepção de Tamanho , Percepção Espacial
15.
J Exp Psychol Hum Percept Perform ; 25(2): 531-42, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10205865

RESUMO

To catch a lofted ball, a catcher must pick up information that guides locomotion to where the ball will land. The acceleration of tangent of the elevation angle of the ball (AT) has received empirical support as a possible source of this information. Little, however, has been said about how the information is detected. Do catchers fixate on a stationary point, or do they track the ball with their gaze? Experiment 1 revealed that catchers use eye and head movements to track the ball. This means that if AT is picked up retinally, it must be done by means of background motion. Alternatively, AT could be picked up by extraretinal mechanisms, such as the vestibular and proprioceptive systems. In Experiment 2, catchers reliably ran to intercept luminous fly balls in the dark, that is, in absence of a visual background, under both binocular and monocular viewing conditions. This indicates that the optical information is not detected by a retinal mechanism alone.


Assuntos
Luz , Percepção de Movimento/fisiologia , Adulto , Movimentos Oculares/fisiologia , Fixação Ocular/fisiologia , Humanos , Propriocepção/fisiologia , Retina/fisiologia
16.
J Exp Psychol Hum Percept Perform ; 22(4): 879-91, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8756956

RESUMO

The catchableness of a fly ball depends on whether the catcher can get to the ball in time; accurate judgments of catchableness must reflect both spatial and temporal aspects. Two experiments examined the perception of catchableness under conditions of restricted information pickup. Experiment 1 compared perceptual judgments with actual catching and revealed that stationary observers are poor perceivers of catchableness, as would be expected by the lack of information about running capabilities. In Experiment 2, participants saw the 1st part of ball trajectories before their vision was occluded. In 1 condition, they started to run (as if to catch the ball) before occlusion; in another, they remained stationary. Moving judgments were better than stationary judgments. This supports the idea that perceiving affordances that depend on kinematic, rather than merely geometric, body characteristics may require the relevant action to be performed.


Assuntos
Beisebol/psicologia , Percepção de Movimento , Orientação , Reconhecimento Visual de Modelos , Desempenho Psicomotor , Adulto , Atenção , Humanos , Cinestesia , Masculino , Mascaramento Perceptivo , Propriocepção , Psicofísica , Meio Social
17.
Med Sci Sports Exerc ; 28(10): 1305-10, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8897389

RESUMO

Sport scientists have identified many factors as prerequisites for a good athletic performance in various sports. It is not clear whether these factors also influence the best performers in the homogeneous groups of top athletes selected for national teams. In this study, this issue is addressed with members of the Dutch National Junior Speed Skating Team. A total of 237 different technical, physiological, anthropometrical, and psychological parameters were collected, including many that correlated with performance in previous studies. High speed film analyses during the National Championships provided the technique parameters. A 30-s sprint test and a 150-s supramaximal test on a cycle ergometer underlie the physiological data, and questionnaires were used to measure personality traits and emotional feelings. Only trunk position and the direction of push-off (push-off angle phi) correlated consistently with skating performance in this group (r = 0.61-0.73 and r = -0.65 to -0.70, respectively). The small number of meaningful correlations means that sport scientists will have to develop more reliable methods, models, and theories to contribute significantly to knowledge useful to top athletes and their coaches.


Assuntos
Patinação/fisiologia , Adolescente , Adulto , Antropometria , Fenômenos Biomecânicos , Estudos Transversais , Emoções , Feminino , Humanos , Masculino , Consumo de Oxigênio , Personalidade , Patinação/psicologia , Inquéritos e Questionários
18.
J Psychosom Res ; 35(2-3): 323-33, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-2046064

RESUMO

The central issues of the present paper are the responses to the stress of lecturing in a standardized situation, and the adaptation to this stressor across a period of real-life lecturing practice. Special attention is given to the stability of rank-order in the physiological and psychological responses to the lecturing stressor across practice. Lecturing in the standardized situation involved lecturing at the training institute to six fellow student teachers and two members of the university staff. The responses to be measured were heart rate, cortisol excretion and subjective anxiety. The results indicate that lecturing is stressful for student teachers. The adaptation in stress responses was very significant. Despite the significant reduction in the stress responses, a considerable stability of rank-order was found, indicating that subjects who were the most reactive before practice were still more reactive after practice. The implications of a high stability in reactivity are discussed.


Assuntos
Adaptação Psicológica , Nível de Alerta , Prática Psicológica , Meio Social , Comportamento Verbal , Adaptação Psicológica/fisiologia , Adulto , Nível de Alerta/fisiologia , Pressão Sanguínea/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Ensino , Comportamento Verbal/fisiologia
19.
J Psychosom Res ; 35(1): 11-24, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-2023139

RESUMO

The aim of this study was to evaluate the moderating effect of several psychologically and biologically defined characteristics for both psychological and physiological indices of reactivity to and coping with lecturing stress. Student teachers were measured in two standardized lecturing situations: once at the start of a three-month practice period and once at the end of this period. Reactivity was operationalized as an increase in heart rate, cortisol excretion and subjective anxiety responses in anticipation of and at the start of the lecture. Coping was operationalized as the attunement of these responses during, or recovery after lecturing (short term coping), and as the adaptation of these responses across the three-month practice period (long term coping). It was found that reactivity to and (particularly long term) coping with the lecturing stressor could well be predicted by moderators such as physical fitness, extraversion, neuroticism, social anxiety and several coping styles. Specificity of predictor sets for sex and response parameters is discussed.


Assuntos
Adaptação Psicológica , Nível de Alerta , Individualidade , Meio Social , Comportamento Verbal , Adaptação Psicológica/fisiologia , Adulto , Ansiedade/sangue , Ansiedade/psicologia , Nível de Alerta/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Comportamento Verbal/fisiologia
20.
Eur J Emerg Med ; 8(1): 39-42, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11314820

RESUMO

Survival of patients with traumatic rupture of the thoracic aorta (TRTA) depends on early surgical repair. Six cases of TRTA were treated at our institution in 7 years. Time to diagnosis was 1.5, 3, 4, 36, 91 and 140 hours (mean = 46 hours). Diagnosis was made by computed tomography in one and by angiography in five cases. Time from arrival to treatment was 3, 9, 5, 46, 117 and 152 hours (mean = 55 hours). All six patients were treated by clamp and suture technique, with a mean cross clamp time of 48 minutes. Significant delay in diagnosis and treatment occurred in three patients. The reasons for delay were unrecognized signs for TRTA on the initial chest X-ray, a false-negative result of transoesophageal echography and not considering the diagnosis of TRTA. The diagnosis of TRTA requires a high index of suspicion and should always be considered in victims of high impact trauma.


Assuntos
Aorta Torácica/lesões , Ruptura Aórtica/diagnóstico por imagem , Traumatismo Múltiplo/diagnóstico por imagem , Adulto , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/cirurgia , Ruptura Aórtica/cirurgia , Aortografia , Feminino , Humanos , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , Traumatismo Múltiplo/cirurgia , Valor Preditivo dos Testes , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Ferimentos não Penetrantes/diagnóstico por imagem , Ferimentos não Penetrantes/cirurgia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA