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D Van Neste† RM Trüeb‡ 《Journal of the European Academy of Dermatology and Venereology》2006,20(5):578-583
BACKGROUND: Computer-assisted image analysis has been proposed for human hair growth studies. METHODS: The performances of Trichoscan, a commercially available automated system combining epiluminiscence microscopy with digital image analysis, developed for office-based hair growth measurements, have been evaluated comparatively on the same skin sites using standardized photographic equipment and calibrated processing for contrast-enhanced phototrichogram (CE-PTG) analysis. This reference method has been validated with scalp biopsies and histological examination of serial sectioning. RESULTS: Besides edge effects, hair fibres escaped the Trichoscan analysis for various reasons including, but not limited to, thickness, pigmentation, closeness and crossing. CONCLUSION: Most of these problems have been identified in the late 1980s and remain largely unsolved by the processing software that was evaluated in 2004. Therefore claims promoting the Trichoscan method for accurate hair measurements in clinical trials on scalp and body hair are not supported by the present investigation. The speed at which the analysis is performed is outweighed by the errors in signal detection. Therefore we suggest that improvements must be clearly documented before Trichoscan is established for quantified diagnostic purposes and detailed hair cycle monitoring during hair trials. 相似文献
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A. Heinig S. H. Heywang-Köbrunner P. Viehweg D. Lampe J. Buchmann R. P. Spielmann 《Der Radiologe》1997,37(9):710-717
Summary
Early recognition of recurrence and work-up of clinically indeterminate lesions may be impaired after reconstruction with
silicone implants due to superimposition of the implant or to scarring. This study was undertaken to evaluate the use of contrast-enhanced
MRI in patients with silicone implant after breast cancer. Contrast-enhanded MRI was offered to 169 patients. Comparative
two- to three-view mammography was also performed in 169 patients, as well as comparative sonography in 144 patients. Conventional
imaging and clinical examination detected only 8/13 recurrences, whereas 12/13 were detected by MRI. One recurrence had been
visible as a strongly enhancing 2-mm dot in a previous examination (2 years before), but was not called. It was therefore
counted as false negative. In addition, multicentricity was detected by MRI alone in two of three cases. MRI correctly diagnosed
scar tissue in all cases with indeterminate findings. However, due to false-positive calls caused by enhancing granulomas
specificity could not be improved. Contrast-enhanded MRI allowed decisive additional information in our study group and improved
the sensitivity significantly (concerning all diagnoses). Contrast-enhanded MRI is recommended in patients with diagnostic
problems or high risk of recurrence after silicone implants.
相似文献
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Differential diagnosis of poisoning by North American mushrooms, with particular emphasis on Amanita phalloides-like intoxication 总被引:2,自引:0,他引:2
It is possible to determine the management and prognosis of mushroom poisoning from the history and initial symptoms with a high degree of confidence. The most important intoxications are those involving Amanita phalloides or other potentially fatal amatoxin-containing mushrooms, which have a latent period of ten to 12 hours before the patient becomes symptomatic. Because aggressive gastroenteric decontamination can reduce the extent of hepatic damage, it is important to attempt to determine during this asymptomatic period whether amatoxin exposure has occurred. Various laboratory methods that might be useful are reviewed. 相似文献
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Birgit Herting MD Bettina Beuthien‐Baumann MD Katrin Pöttrich PhD Markus Donix MD Antje Triemer PhD Johannes B. Lampe MD Rüdiger von Kummer MD Karl Herholz MD Heinz Reichmann MD Vjera A. Holthoff MD 《Movement disorders》2007,22(4):490-497
Depressive symptoms are common in patients with neurodegenerative disorders. Imaging studies suggest that a disruption of frontal-subcortical pathways may underlie depression associated with basal ganglia disease. This pilot study tested the hypothesis that frontal dysfunction contributes to depression associated with multiple system atrophy (MSA) and progressive supranuclear palsy (PSP). Depressed patients with MSA (n = 11), PSP (n = 9), and age-matched controls (n = 25) underwent measures of cerebral glucose metabolism applying positron emission tomography with (18)F-fluorodeoxyglucose. Regional metabolism in the patient groups was compared to the normal subjects using the voxel-based statistical parametric mapping. Depressive symptom severity (Hamilton Depression Rating) and degree of locomotor disability (Hoehn & Yahr) were assessed in the patient groups. The association between prefrontal metabolism and the occurrence of depressive symptoms and the degree of locomotor disability was investigated. When compared to controls, MSA patients revealed significant metabolic decreases in bilateral frontal, parietal, and cerebellar cortex and in the left putamen. In PSP patients, significant hypometabolism was demonstrated in bilateral frontal cortex, right thalamus, and midbrain. Depression severity but not the patients' functional condition was significantly associated with dorsolateral prefrontal glucose metabolism in both patient groups. The findings of this pilot study support the hypothesis that depressive symptoms in MSA and PSP are associated with prefrontal dysfunction. 相似文献
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V Schleyer† S Radakovic-Fijan‡ S Karrer† T Zwingers§ A Tanew‡ M Landthaler† RM Szeimies† 《Journal of the European Academy of Dermatology and Venereology》2006,20(7):823-828
BACKGROUND: Based on good results in the treatment of superficial skin tumours, since the early 1990s topical photodynamic therapy with aminolaevulinic acid (ALA PDT) has been used for disseminated, inflammatory dermatoses including psoriasis. However, there is still a lack of well-documented trials. OBJECTIVE: A prospective randomized, double-blind phase I/II intrapatient comparison study was conducted in 12 patients to investigate whether topical ALA PDT is an effective treatment for chronic plaque-type psoriasis. METHODS: In each patient three psoriatic plaques were randomly treated with a light dose of 20 J/cm(2) and 0.1%, 1% and 5% ALA, respectively. Treatment was conducted twice a week until complete clearance or for a maximum of 12 irradiations. Therapeutic efficacy was assessed by weekly determination of the psoriasis severity index (PSI). RESULTS: The mean percentage improvement was 37.5%, 45.6% and 51.2% in the 0.1%, 1% and 5% ALA-treated groups, respectively. Irradiation had to be interrupted several times because of severe burning and pain sensation. CONCLUSION: Topical ALA PDT did not prove to be an appropriate treatment option for plaque-type psoriasis due to disappointing clinical efficacy, the time-consuming treatment procedure and its unfavourable adverse event profile. 相似文献
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