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1.
Clin Exp Dermatol ; 28(5): 531-4, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12950346

RESUMO

Although often associated with overuse of topical corticosteroids, perioral dermatitis seems to develop seldom in patients with typical seborrhoeic dermatitis in spite of long-term application of corticosteroids. In order to compare the profiles of intrafollicular microorganisms in the lesions of perioral and seborrhoeic dermatitis, tape-stripped samples were obtained from eight lesions of perioral dermatitis, 10 lesions of seborrhoeic dermatitis, and the perioral skin of 31 normal subjects. After staining with Toluidine blue, resident microorganisms on plucked hair roots were evaluated microscopically. In all patients with perioral dermatitis and two normal subjects, 20-70% of sample hairs were positive for fusiform bacteria regarded as fusobacteria. Malassezia-positive hairs were rarely seen in these cases. Seborrhoeic dermatitis showed the opposite results. Perioral dermatitis may tend to develop under fusiform-bacteria-rich conditions, rather than Malassezia-rich conditions as in the case of seborrhoeic dermatitis.


Assuntos
Dermatite Perioral/microbiologia , Dermatite Seborreica/microbiologia , Adulto , Idoso , Dermatomicoses/complicações , Feminino , Fusobacterium/isolamento & purificação , Infecções por Fusobacterium/complicações , Cabelo/microbiologia , Humanos , Malassezia/isolamento & purificação , Masculino , Pessoa de Meia-Idade
2.
IUBMB Life ; 51(1): 39-43, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11419694

RESUMO

In this study, we investigated lipid peroxidation in rat heart mitochondria hydrolyzed by phospholipase A2 (PLA2) and lipid peroxidation in a mitochondrial-mimetic lipid peroxidation system, where phospholipids such as cardiolipin (CL) and cytochrome c (Cyt c) were first mixed together and then PLA2 and calcium chloride were added to the mixture (CL-Cyt c-PLA2 system). Production of hydroperoxy and hydroxy compounds of linoleic acid (LA) in the mixture was measured by high performance liquid chromatography. The ratio of the total amount of hydroperoxy and hydroxy compounds of LA to that of LA was calculated as an index for lipid peroxidation (1000 x mol/mol). The index for lipid peroxidation in the rat heart mitochondria hydrolyzed by PLA2 at the physiological pH of 7.4 was 22.8 +/- 2.2 (mean +/- SD, n = 4) and that at the acidic pH of 6.7 was 41.8 +/- 2.0. In the presence of the thiol (SH)-oxidizing agent diamide, the index was 47.0 +/- 2.6 (pH 7.4). In the CL-Cyt c-PLA2 system, lipid peroxidation seemed to be due to three mechanisms: (1) oxidation of the LA (nonreleased form) constituent of CL by Cyt c (oxidation of CL by Cyt c); (2) oxidation of free LA, released from CL, involving the oxidation of CL by Cyt c (free LA oxidation by the CL-Cyt c complex); and (3) oxidation of free LA, released from CL, by Cyt c and calcium ions (LA-Cyt c-Ca system). The lipid peroxidation of the CL-Cyt c-PLA2 system was also enhanced by the addition of diamide and by an acidic pH of 6.7. The fact that the SH-oxidizing agent enhanced the lipid peroxidation in the CL-Cyt c-PLA2 system suggested that SH groups in the hemoprotein played an inhibitory role in lipid peroxidation in the system.


Assuntos
Cardiolipinas/metabolismo , Grupo dos Citocromos c/metabolismo , Diamida/farmacologia , Concentração de Íons de Hidrogênio , Peroxidação de Lipídeos/efeitos dos fármacos , Mitocôndrias Cardíacas/metabolismo , Animais , Cloreto de Cálcio/farmacologia , Bovinos , Cromatografia Líquida de Alta Pressão , Grupo dos Citocromos c/efeitos dos fármacos , Hemina/metabolismo , Hemoglobinas/metabolismo , Ácido Linoleico/metabolismo , Lipossomos , Masculino , Mitocôndrias Cardíacas/efeitos dos fármacos , Mioglobina/metabolismo , Oxirredução , Fosfolipases A/metabolismo , Fosfolipases A2 , Fosfolipídeos/química , Ratos , Ratos Sprague-Dawley
3.
Nihon Hoigaku Zasshi ; 54(3): 399-407, 2000 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-11218758

RESUMO

We carried out a questionnaire survey on judicial apprentices with a case died of subarachnoid hemorrhage to examine whether the expression of the text and supplementary explanation of the expert opinion affect judicial decisions and findings of facts. The survey results suggest that both the expressions of the text and the supplementary explanation may have an effect on the decision. That is, judicial apprentices who read the text expressed that "it was not clear whether the subarachnoid hemorrhage was traumatic or not" with the explanation are less likely to indict for injury resulting in death than those who read the text expressed that "it was not contradictory that the subarachnoid hemorrhage was traumatic" without the explanation. Additionally, we found that these two factors affected the reader's findings of fact. Particularly, the text expressed that "it was not contradictory" without a supplementary explanation is prone to give a conclusive conviction to readers. These results suggest that how a medical diagnosis would be legally interpreted in court depend to some extent upon the expression and the supplementary explanation of the expert opinion. The text of an expert opinion should be expressed to report the medical diagnosis exactly. When autopsy cannot determine the definitive cause of the death, detailed explanation should be supplemented lest the expert opinion give a conclusive conviction. Moreover, we suggest that it is necessary to standardize the form and expression of the expert opinion hereafter.


Assuntos
Prova Pericial/normas , Medicina Legal/normas , Causas de Morte , Humanos , Hemorragia Subaracnóidea/diagnóstico , Inquéritos e Questionários
4.
Percept Psychophys ; 61(1): 144-50, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10070206

RESUMO

Stereoscopic depth has a critical effect on completion of partially occluded figures. However, it has not strictly been distinguished whether the effect is direct or indirect through alteration of contour segmentation or parsing. Here, I report that stereoscopic depth does not influence completion of partially occluded figures when parsing is unambiguous from motion cues. This is consistent with the present proposal that stereoscopic depth does not have a unique role in completion and that it is one of the cues to contour segmentation or parsing, which in turn influences completion and surface representation, like motion, shape, or transparency.


Assuntos
Percepção de Profundidade , Ilusões Ópticas , Reconhecimento Visual de Modelos , Fechamento Perceptivo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psicofísica , Visão Binocular
5.
Hum Brain Mapp ; 5(5): 341-6, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-20408238

RESUMO

A novel noninvasive magnetic resonance imaging (MRI) method was developed to determine in vivo blood oxygen saturation and its changes during motor cortex activation in small cerebral veins. Specifically, based on susceptibility measurements in the resting states, pial veins were found to have a mean oxygen saturation of Yrest=0.544+/-0.029 averaged over 14 vessels in 5 volunteers. During activation, susceptibility measurements revealed an oxygen saturation change of DeltaYsusc=0.14+/-0.02. Independent evaluation from blood flow velocity measurements yielded a value of DeltaYflow=0.14+/-0.04 for this change. These results validate the blood oxygenation level-dependent (BOLD) model in functional MRI (fMRI).

7.
Perception ; 24(4): 373-89, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7675618

RESUMO

Amodal completion of partly occluded figures is analyzed as natural computation. Here amodal completion is shown to consist of four subproblems: representation, parsing, correspondence, and interpolation. Second, each problem is shown to be basically solvable on the basis of the generic-viewpoint assumption. It is also argued that the interpolation problem might be the key problem because of mutual interdependence among the subproblems. Third, a theory is described for the interpolation problem, in which the generic-viewpoint assumption and the curvature-consistency assumption are presumed. The generic-viewpoint assumption entails that the orientation and the curvature should not change at the point of occlusion. The curvature-consistency assumption entails that the hidden contour should have the minimum number of inflections to maintain continuity in orientation and curvature. The shape of the interpolated contour represented qualitatively in terms of the number of inflections can uniquely be determined when the location of the terminators and local orientation and curvature of the visible contours at the terminators are given. Fourth, it is shown in an instant psychophysics that the theory is highly consistent with human performance.


Assuntos
Atenção , Percepção de Forma , Fechamento Perceptivo , Mascaramento Perceptivo , Adulto , Humanos , Masculino , Reconhecimento Visual de Modelos , Resolução de Problemas , Psicofísica
8.
Perception ; 24(9): 1011-20, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8552455

RESUMO

The effect of curvature on visual interpolation in partly occluded figures was examined. In experiments 1 and 2, the shape of a visually interpolated contour was measured by using a partially occluded triangle or a partially occluded circle as the target figure. The targets were cut off at both sides, with varying width from trial to trial. In experiment 1, the peak height, which was supposed to represent the shape of the interpolated contour, was measured for each target for each size of the visible part. A significant effect of curvature, as the difference in the peak height between the targets, was found when the width of the visible part was 10 to 20 min. The effect became stronger linearly with increasing length of the visible contour (the buildup effect). The effective curvature thus appeared to be measured along the visible contour in terms of the change of orientation. In experiment 2, the scale invariance of the buildup effect was examined with varying observation distance. It was found that the effect remained the same across scale if the effect was described in terms of visual angle of the visible arc, but not in terms of the proportion of the visible part to the whole figure. This suggests that the effect is derived from the visible contour, but not from the likelihood of the estimated shape of the partly occluded figure. It has been concluded that the curvature induces curved interpolation and that the curvature of the visible contour is measured along the contour as the change of orientation.


Assuntos
Reconhecimento Visual de Modelos , Adulto , Sinais (Psicologia) , Humanos , Funções Verossimilhança , Análise de Regressão
9.
Methods Inf Med ; 33(1): 97-100, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8177090

RESUMO

It is estimated that, in Japan, several million people suffer from urinary incontinence caused by, e.g., cerebrovascular disease, abdominal operations, spinal-cord damage, etc. Urinary incontinence is said to be a 'hidden' disease. When no adequate treatment is given, a serious situation may arise for both patients and their family. A non-invasive and unconstrained ultrasonic sensor has been designed enabling patients to discretely manage urination. The major problem of the sensor is how to maintain a proper irradiation angle to obtain an anteroposterior bladder diameter which corresponds to the actual bladder volume. Many types of ultrasonic probe holders have been tested and promising results have been obtained. The most practical, but as yet experimental, method is a four-element ultrasonic sensor, embedded in a flat probe.


Assuntos
Bexiga Urinária/diagnóstico por imagem , Incontinência Urinária/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Desenho de Equipamento , Feminino , Assistência Domiciliar , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica/instrumentação , Ultrassonografia , Incontinência Urinária/fisiopatologia , Urina
10.
Perception ; 23(9): 1025-36, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7899044

RESUMO

Binocular displacement of binocularly unpaired parts of the stimulus was examined by means of the Poggendorff figure. The Poggendorff figure can be used to investigate displacement since lateral displacement of the transversal may cause bias in judgments of its collinearity. In experiment 1, the transversal had a disparity, and thus binocularly unpaired parts, relative to the rectangle. The magnitude of the Poggendorff illusion should not have changed by addition of binocular disparity if displacement occurred. There was no or slight change when the transversal was seen behind the rectangle, but there was significant decrease when the transversal was seen in front of the rectangle, suggesting absence of displacement in this case. There were two possible explanations. One was that displacement depended on the positional relation between the unpaired stimuli and the binocularly presented rectangle, ie the occlusion constraint, which the case with the transversal in front did not satisfy. The alternative was that the decrease was due to the perceived front depth of the transversal, and not related to binocular displacement at all. In order to discriminate between these two possibilities, the transversal was reduced to only the unpaired parts, resulting in dichoptic stimulation in experiment 2. In this stimulus, the positional relation between the unpaired and the paired stimuli was the same as in the previous experiment, yet no front depth could be perceived. The results showed similar asymmetry as in experiment 1. Thus we conclude that binocular displacement depends on the positional relation between the unpaired and the paired stimuli, regardless of their perceived depth. This may imply that binocular displacement is not symmetric about the sign of disparity, hence that it is not just averaging but is a reconstruction of the spatial layout of objects in the outside world to keep the visual direction of the unsuppressed unpaired region veridical by using explicit cues to depth discontinuity.


Assuntos
Ilusões Ópticas , Disparidade Visual/fisiologia , Visão Binocular/fisiologia , Sinais (Psicologia) , Lateralidade Funcional , Humanos , Reconhecimento Visual de Modelos , Percepção Espacial , Campos Visuais
11.
Perception ; 21(3): 313-24, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1437450

RESUMO

Two aspects of neon color spreading, local color spreading (neon flank) and illusory contour, were investigated by dichoptic viewing. Neon flank was not observed under appropriate dichoptic stimulation, suggesting that input to the process for local color spreading is based on monocular configuration. However, illusory contours were formed according to the interocularly combined configuration rather than according to each monocular configuration, suggesting that input to the process responsible for illusory contours should be ocularly-nonselective and binocular, rather than monocular. The possibilities of artifacts such as those arising from interocular rivalry were appropriately eliminated, and thus, it is tentatively concluded that the process underlying local color spreading is monocularly driven, whereas the process underlying illusory contours is binocularly driven. Furthermore, a new demonstration is presented that indicates that interocularly-induced illusory contours 'capture' and extend the monocularly-induced local color spreading, resulting in global color spreading (neon color spreading). These results support our hypotheses that neon color spreading involves two separable processes in the early visual processing, the feature detection process (for local color spreading) and the illusory contour process, and that these two processes interact with each other at later stages of cortical processing. The relation of local color spreading and illusory contours to surface separation is also discussed.


Assuntos
Percepção de Cores , Percepção de Forma , Ilusões Ópticas , Percepção Visual , Adulto , Desenho de Equipamento , Feminino , Humanos , Masculino , Projetos de Pesquisa
12.
Perception ; 21(2): 177-84, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1513667

RESUMO

A novel kind of depth-spreading effect which should be distinguished in various aspects from the known interpolation, averaging, or 'filling-in' phenomena is reported. The demonstrations and experiments suggest that depth from an uncrossed disparity can be extrapolated from, not just interpolated between, illusory or real contours to form perceptually a background surface. In addition, the form of the illusory contour itself could be drastically changed in configuration and sharpness, contingently with perceptual background-surface formation. No such effects of surface and contour formation were observed in the crossed disparity case. Because the illusory contours were enhanced and perceived as illusory 'occluding contours', these effects may be closely related to the 'occlusion constraints' in the real world.


Assuntos
Atenção , Percepção de Profundidade , Ilusões Ópticas , Reconhecimento Visual de Modelos , Mascaramento Perceptivo , Sensibilidades de Contraste , Aprendizagem por Discriminação , Humanos , Orientação , Psicofísica
13.
Percept Psychophys ; 47(5): 457-67, 1990 May.
Artigo em Inglês | MEDLINE | ID: mdl-2349058

RESUMO

In the present study, we examine the relation between neon color spreading (Redies & Spillmann, 1981) and illusory contours. In Experiment 1, the effects of misalignment between the line elements on the illusory contours in the Ehrenstein figure and in the Redies-Spillmann figure were examined. The remarkable overlap of the two curves for the likelihood of perceiving illusory contours in the Ehrenstein figure and in the Redies-Spillmann figure suggests that the illusory contours surrounding brightness enhancement (Ehrenstein, 1941) and those surrounding neon color spreading are caused by the same mechanism. We further examined both the effects of the interposed grids seen either in front of or behind the figures (Experiment 2) and the effects of misalignment (Experiment 3) on the illusory contours and range of color spreading, and found a high correlation between the appearance/disappearance of illusory contours and global/local color spreading. In Experiment 4, we added new lines to induce illusory contours to the line elements inducing local color spreading. We found that global color spreading was seen to cover the area surrounded by the illusory contours. On the basis of these findings, we suggest that there is an interaction between illusory contours and local color spreading.


Assuntos
Percepção de Cores , Percepção de Forma , Ilusões , Ilusões Ópticas , Adulto , Atenção , Humanos , Masculino , Orientação
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