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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 vagal nerve as a link between the nervous and immune system in the instance of polymicrobial sepsis 总被引:5,自引:0,他引:5
Wolfram Kessler Tobias Traeger Alexandra Westerholt Friederike Neher Marlene Mikulcak Antje Müller Stefan Maier Claus-Dieter Heidecke 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2006,391(2):83-87
Background The role of the vagal nerve in the autonomic nervous system is widely well known. Recently, an additional function was revealed
serving as a connector between the nervous and immune system. This connection is called the “cholinergic inflammatory pathway.”
Through stimulation of the acetylcholine receptors located upon the macrophages, the “unspecific” immune system can be directly
influenced.
Methods The vagal nerve was completely transected directly posterior to its passage through the diaphragm. The effect of complete
vagotomy was analyzed using a murine model of polymicrobial peritonitis (colon ascendens stent peritonitis, CASP). Survival
and clinical course of vagotomized or sham-operated mice were analyzed in the CASP model.
Results After CASP surgery, vagotomy led to a significantly increased mortality (64.7%) in comparison to sham-vagotomized animals
(34%). No difference in the bacterial load of various tissues (lung, liver, spleen, blood, lavage fluid, and kidney) from
septic animals with or without vagotomy was observed. Vagotomized animals reveal elevated serum cytokine levels (TNF, IL-6,
IL-10, and MCP-1) 20 h after the induction of polymicrobial peritonitis.
Conclusion The vagal nerve is therefore an important modulator of the immune system.
W. Kessler and T. Traeger contributed equally to this work
Best of Forum Papers presented at the Annual Meeting of the German Society of Surgery, 2–5 May 2006, Berlin, Germany 相似文献
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The course of schizophrenia: Some remarks on a yet unsolved problem of retrospective data collection
Wolfram an der Heiden Bertram Krumm 《European archives of psychiatry and clinical neuroscience》1991,240(4-5):303-306
Summary The retrospective assessment of symptoms and syndromes is a basic measure in research of the longitudinal course of schizophrenia. In spite of its importance there have been few studies evaluating the standard of quality of instruments for retrospective data collection. Combining retrospectively and cross-sectionally collected data on schizophrenic symptomatology in a cohort study over a period of 5 years revealed a significant underestimation of symptoms when assessed in retrospect. The need for studies on the validity of instruments for the retrospective assessment of symptoms is stressed. 相似文献
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Differential Stripping: Determination of the Amount of Topically Applied Substances Penetrated into the Hair Follicles
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Alexa Teichmann Ute Jacobi Michael Ossadnik† Heike Richter Stefan Koch† Wolfram Sterry Jürgen Lademann 《Journal of general internal medicine》2005,20(5):264-269
The determination of penetration pathways of topically applied substances into the skin is the subject of several investigations. Recently, follicular penetration has become a major focus of interest. To date, a direct, non-invasive quantification of the amount of topically applied substance penetrated into the follicles had not been possible. The development of such a method was the aim of this study. Therefore, the advantages of both stripping techniques, tape stripping and cyanoacrylate skin surface biopsy, were combined and evaluated. Tape stripping was used to remove the part of the stratum corneum that contained the topically applied dye. Subsequently, the follicular contents were ripped off by cyanoacrylate skin surface biopsy. The combined method termed "differential stripping" was evaluated in vitro and in vivo , and the amount of topically applied fluorescent dye penetrated into the hair follicles was quantified after different penetration times. After 30 min, 5% of the recovered concentration of sodium fluorescein was found in the follicular infundibula, where it was still detectable after 48 h. Altogether, the results of this investigation revealed that differential stripping is a new method that can be used to study the penetration of topically applied substances into the follicular infundibula non-invasively and selectively. 相似文献
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Prof. Dr. E. Minar B. Pokrajac R. Wolfram A. Budinsky C. Kirisits R. Pötter 《Gef?sschirurgie》2003,8(2):75-84
The therapeutic concept of irradiation of the vessel wall for prevention of restenosis after endovascular procedures is based on increasing knowledge about the pathophysiology of the process leading to restenosis. There is until now only a limited number of studies concerning the use of brachytherapy (BT) in the peripheral circulation, which is in contrast to the already large experience in the coronary circulation. In the peripheral trials the radiation dose was administered by a remote afterloader using a gamma source. According to the available data, vascular BT is a promising technology with the potential to reduce the restenosis rate. The Vienna-2-Trial was the first randomised study to demonstrate the efficacy of endovascular BT for prophylaxis of restenosis after femoropopliteal percutaneous transluminal angioplasty. However, we have to await further supportive data from ongoing clinical trials before definitive recommendations can be given. Currently, endovascular BT seems already justified in patients with recurrent interventions or after long-segment femoropopliteal angioplasty because of the high risk of restenosis in these patients. The next years will demonstrate the ultimate role of endovascular BT in comparison to the rapidly evolving field of drug-eluting stents. 相似文献