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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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Philip W. Wirtz 《Alcoholism, clinical and experimental research》2007,31(S3):57s-63s
Background: While causal modeling is generally well known to alcohol researchers, several causal structures (including suppression, mediated moderation, and moderated mediation) are often poorly understood and seldom employed when investigators seek to model the complex mechanisms of behavior change, despite their widespread applicability to the field.
Methods: This paper compares and contrasts five basic structures of causal modeling in the context of contemporary alcohol research and demonstrates how mechanisms of behavior change can be conceptualized and tested as parallel and serial sequences of these basic causal structures, forming causal chains.
Conclusion: Recent methodological developments, while representing an important advancement for the field, fail to adequately address the complexities of alcohol dependence phenomena. A differentiation between frequently combined forms of these causal structures is proposed that would better address the needs of the field. 相似文献
Methods: This paper compares and contrasts five basic structures of causal modeling in the context of contemporary alcohol research and demonstrates how mechanisms of behavior change can be conceptualized and tested as parallel and serial sequences of these basic causal structures, forming causal chains.
Conclusion: Recent methodological developments, while representing an important advancement for the field, fail to adequately address the complexities of alcohol dependence phenomena. A differentiation between frequently combined forms of these causal structures is proposed that would better address the needs of the field. 相似文献
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R. Fock H. Bergmann H. Bußmann G. Fell E.-J. Finke U. Koch M. Niedrig M. Peters D. Scholz A. Wirtz 《Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz》2001,44(10):969-980
The World Health Organization (WHO) and the majority of the influenza experts assume that an influenza pandemic might reemerge again at any time. Therefore WHO has called upon all member states to set up a national pandemic preparedness plan. For Germany such a plan is long overdue. In order to gain as much time as possible early identification of the pandemic virus is of highest priority. Furthermore progression of a pandemic is influenced by the time needed to develop a subtype specific vaccine as well as by the vaccines availability. However, in case of a pandemic a shortage of vaccines and prophylactic pharmaceuticals cannot be avoided. Therefore, decisions have to be made in order to establish priorities concerning the vaccination and the prophylactic and/or therapeutic antimicrobial treatment of selected sub-populations. There is also a need to lay down measures ensuring the distribution of vaccines and antiviral drugs, adequate health care and ambulance service, and the organization of dignified funerals of the deceased. It is also necessary to enter into an early agreement with vaccine manufacturers on a guaranteed supply of respective batches of vaccine doses. In addition procedures should be established to allow an increase in vaccine production in case of a pandemic. There is also a need for early agreements with the manufacturers of antiviral agents and for a decision concerning the establishment of a national stockpile to guarantee an adequate supply. Some measures must already be taken in the inter-pandemic period. Those are: enhancement of surveillance and research, development of new vaccines and new methods of vaccine production, licensing of new vaccines in case of a pandemic and establishment of a national influenza committee. Problems like the effectiveness of antiepidemic measures, such as immigration control and the closing of schools, must be solved in advance of a pandemic. 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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Zusammenfassung Hintergrund: Bei Patienten mit stumpfem Thoraxtrauma muss mit einer Contusio cordis gerechnet werden. Das Spektrum der Symptomatik variiert von einer leichten regionalen myokardialen Funktionsstörung bis hin zur Ruptur und zum plötzlichen Herztod. Fallbeschreibung: Ein 27-jähriger Patient wurde nach einem Fußtritt gegen die Brust bei Kammerflimmern reanimiert. Das EKG sowie das Enzymmuster entsprachen denen eines akuten Myokardinfarkts, echokardiographisch zeigte sich eine Hypokinesie apikal und anteroseptal bei mittelgradig reduzierter Pumpfuktion. Die 10 Tage nach dem Trauma durchgeführte Koronarangiographie und Lävokardiographie ergaben einen unauffälligen Befund. Schlussfolgerung: Als Ursache des primären Kammerflimmerns und der initialen elektro- und echokardiographischen Befunde muss aufgrund der Anamnese eine Contusio cordis diskutiert und in der Therapie berücksichtigt werden. Abstract Background: Patients with a blunt chest trauma often sustain myocardial contusion. The spectrum of symptoms varies from regional myocardial dysfunction to myocardial rupture of sudden cardiac death. Case Report: After a kick against his chest, a 27-year-old patient was resuscitated because of ventricular fibrillation. ECG and enzymatic pattern corresponded to an acute myocardial infarction, the echocardiogram revealed an apical and anteroseptal hypokinesia. 10 days after the acute event, coronary arteriography and ventriculography did not show any abnormalities. Conclusion: On the basis of the anamnesis, a myocardial contusion must be discussed as reason for the ventricular fibrillation and the pathologic findings in ECG and echocardiogram. This has to be considered in the therapy. 相似文献