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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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The long-term cost of effective management for benign prostatic hyperplasia (BPH) remains an important issue in pharmacoeconomics because about 25% of men aged 50 yr and older experience voiding problems due to BPH. With the ageing population and the increase in the percentage of patients with BPH for whom any type of treatment can be considered, a substantial increase in total costs to society can be expected. The up-front costs of interventional approaches to BPH are being replaced by a pattern of long-term medical and preventive therapy. The age-adjusted rate of transurethral resection of the prostate (TURP) reached a high point in 1987 and TURP rates, but not costs, have been in decline ever since. Mean 1-yr treatment costs (medical therapy and TURP) have been estimated in a pan-European study to be 858 Euros per patient, 75% of which were medication costs. Using a 2-yr time frame for treatment, Medicare costs for finasteride, terazosin, and TURP have been estimated as $3874, $2161, and $1820, respectively. The available models of the total long-term cost for all therapies for BPH remain compromised by a lack of inclusion of indirect costs, the lack of true long-term data and, critically, the lack of human cost information (patient preference). Only medical therapy provides a preventive as well as symptomatic potential and, if all of the issues were fully incorporated, it is likely that medical therapy would be increasingly recognised as economically preferable. 相似文献
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G Zamboni G Franzin F Bonetti A Scarpa M Chilosi R Colombari F Menestrina M Pea C Iacono G Serio 《The American journal of surgical pathology》1990,14(8):703-713
We report the clinicopathologic, immunohistochemical, and ultrastructural features of three small-cell neuroendocrine carcinomas of the ampullary region of the duodenum. All patients were men; their ages were 51, 62, and 66 years. The therapy consisted of pancreatoduodenectomy. All patients died of the disease; median survival was 10 months from the diagnosis. The histological appearance was identical to pulmonary and extrapulmonary small-cell carcinoma. The neuroendocrine differentiation was demonstrated ultrastructurally by the presence of dense-core granules, and by the positive immunoreaction for neuron-specific enolase and Leu-7 in each case. One case expressed a focal positivity for chromogranin A (PHE-5) and argyrophilic granules. The same case showed the presence of neurofilaments on frozen material. Neurofilament proteins could not be demonstrated in any case in paraffin sections. Neoplastic cells exhibited cytoplasmic immunostaining for cytokeratins (CAM 5.2) in all cases. In one case, a large number of neoplastic cells (60-70%) exhibited nuclear Ki-67 positivity. We postulate that the disease's histogenesis was from epithelial stem cell expressing both epithelial and neuroendocrine characteristics. The clinical behavior of small-cell neuroendocrine carcinomas of the ampullary region appears to be extremely aggressive, with early metastases and fatal outcome. 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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The temporal coupling between the transport and grasp components of prehension movements was investigated through two experiments. In Experiment 1, six normal subjects were required to reach and grasp each of three spheres located at three different distances (Blocked trials). In Experiment 2, a visual perturbation paradigm was used in which the location of the object to be reached and grasped could change at the beginning of arm movement (Perturbed trials). The same subjects participated in both experiments. Kinematics of wrist trajectory (transport component) and of distance between thumb and index finger (grasp component) were analyzed. The results of Experiment 1 showed that the two components could be temporally coupled during their time course. In Experiment 2, the visual perturbation affected both the components, but different times were required by each component to reorganize the movement towards the new target. These different times caused the decoupling of those events that appeared synchronized in Experiment 1. Finally, evidence was found to suggest that planning of grip formation takes into account not only the perceived characteristics of the object, but also the time planned by the transport component to reach the object. 相似文献
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