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31.
Ligia Teban Hubert Pehamberger Klaus Wolff Michael Binder Harald Kittler 《Journal der Deutschen Dermatologischen Gesellschaft》2003,1(4):292-296
Background and objectives: The aim of this study was to evaluate the practical value of the dermatoscopic classification of Clark nevi Patients and methods: Dermatoscopic images of 268 lesions clinically and dermatoscopically diagnosed as Clark nevi were presented to 2 dermatologists without knowledge of the histological diagnosis. The dermatologists evaluated the lesions according to a simplified version of the classification scheme for Clark nevi proposed by Hofmann‐Wellenhof and differentiated between 12 different types of Clark nevi. Results: The most common type of Clark nevus was the reticular‐homogenous type (n = 64, 23,9 %), followed by the globular‐homogeneous type (n = 32, 12 %) and by the homogenous type (n = 30, 11,2 %). The overall inter‐rater agreement between the examiners was moderate to good (kappa = 0,58). The highest level of agreement was found for the peripheral hyperpigmented type (kappa = 0,83). Histologically, 17 lesions (6,3 %) were diagnosed as melanomas. The frequency of melanoma was highest among the peripheral‐hyperpigmented type for one observer and among the homogenous type for the other observer. No melanoma was found among the globular, reticular‐globular, and the central‐hyperpigmented types. Conclusions: A dermatoscopic classification of Clark nevi is practically feasible and allows – to some extent – a risk stratification of Clark nevi, which could be useful for clinical management. 相似文献
32.
Monitoring left ventricular dilation in mice with PET. 总被引:3,自引:0,他引:3
Lars Stegger Klaus P Sch?fers Ulrich Fl?gel Lefteris Livieratos Sven Hermann Christoph Jacoby Petra Keul Edward M Conway Otmar Schober Jürgen Schrader Bodo Levkau Michael Sch?fers 《Journal of nuclear medicine》2005,46(9):1516-1521
Molecular imaging by small-animal PET is an important noninvasive means to phenotype transgenic mouse models in vivo. When investigating pathologies of the left ventricular (LV) myocardium, the serial assessment of LV volumes is important. By this, the presence of LV dilation as a sign of developing heart failure can be detected. Whereas PET is usually used to derive biochemical and molecular information, functional parameters such as ventricular volumes are generally measured using echocardiography or MRI. In this study, a novel method to monitor LV dilation in mice with PET is presented and evaluated using cardiac MRI. METHODS: A semiautomatic 3-dimensional algorithm was used to delineate the LV myocardial wall on static PET images depicting myocardial glucose metabolism ((18)F-FDG PET) for 20 mice: 10 wild-type and 10 genetically modified littermates designed to develop a dilative cardiomyopathy phenotype (cardiomyocyte-specific knockout of survivin). The volume enclosed by the 3-dimensional midmyocardial contour was calculated as a measure for LV volume for each mouse. Data were compared with ventricular volumes measured by MRI in the same animals. RESULTS: LV volumes obtained by PET and MRI correlated well (R = 0.89) for hearts with small and large left ventricles. In accordance with the hypothesis, the LV volumes were increased significantly for transgenic mice examined at an older age compared with those examined at a younger age (MRI: 160.5 +/- 25.7 microL vs. 114.7 +/- 15.2 microL [P = 0.012]; PET: 129.3 +/- 15.3 microL vs. 73.8 +/- 15.0 microL [P < 0.001], all values shown as mean +/- SD; for MRI, mean of end-diastolic and end-systolic volumes are given), whereas they did not for their wild-type littermates (MRI: 106.2 +/- 12.3 microL vs. 94.7 +/- 14.6 microL [P = 0.214]; PET: 82.6 +/- 20.9 microL vs. 65.0 +/- 16.9 microL [P = 0.185]). CONCLUSION: Evaluation and quantitation of LV dilation in both control and cardiomyopathic mice can be reliably and serially performed using small-animal PET and (18)F-FDG, yielding useful functional information in addition to metabolic data. 相似文献
33.
Influence of Electromagnetic Fields on Function of Automated External Defibrillators 总被引:3,自引:2,他引:1
Roman Fleischhackl MD Florian Singer MD Wolfgang Nitsche PhD MSc Eng Guenther Gamperl MSc Engineering Bernhard Roessler MD Jasmin Arrich MD Sabine Fleischhackl MD Heidrun Losert MD Fritz Sterz MD Martina Mittlboeck PhD MSc Klaus Hoerauf PhD MD 《Academic emergency medicine》2006,13(1):1-6
Objectives: In this study, the authors tested whether electromagnetic interference (EMI) is able to impair correct electrocardiogram analysis and produce false‐positive shock advice from automated external defibrillators (AEDs) when the true rhythm is sinus. Methods: Nineteen healthy subjects were used to test five AEDs available on the Austrian market in a prospective, open, and sequence‐randomized study. The primary outcome variable was the absolute number of shocks advised in the presence of EMI. The secondary outcome was the number of impaired analyses caused by incorrectly detected patient movements or electrode failure. Results: Of 760 tests run, 18 (2.37%) cases of false‐positive results occurred, and two of five AEDs recommended shocks in the presence of sinus rhythm. Of 760 tests run, no electrode failures occurred. There were 27 occurrences (3.55%) of motion detected by an AED in the presence of strong electromagnetic fields. Conclusions: AED models differ in their response to EMI; it may be useful to consider specific safety requirements for areas with such fields present. Working personnel and emergency medical services staff should be informed about potential risks and the possible need for patient evacuation before AEDs are attached and shock recommendations are followed. 相似文献
34.
Sami R Achem MD Alexander Klaus MD Ronald A Hinder MD PhD Kenneth R DeVault MD 《The American journal of medicine》2004,116(10):717-718
35.
Albert B. Zajko M.D. Klaus M. Bron William L. Campbell 《Cardiovascular and interventional radiology》1987,10(1):28-31
Biliary obstruction and multiple hepatic abscesses occurred in a patient after ligation of a segmental branch of the right
hepatic duct. The patient was successfully managed by transhepatic biliary drainage and balloon dilatation of an internal
fistula that developed between the ligated duct and a Roux limb of jejunum. Internal biliary fistulas may be dilated using
interventioanl radiologic techniques to permit nonobstructed bile flow. Implications for the nonsurgical treatment' of biliary
strictures are discussed. 相似文献
36.
Asymmetric Electrophilic α-Amidoalkylation, 4): Generation and Trapping Reactions of Chiral N- Acylpyrrolidiniumions The pyrrole derivatives 1 , 6 , and 10 react in the presence of TiCl4 with the silyl enol ether 3 to form α-substituted pyrrolidine amides steroselectively. 6 and 10 (after HCl-addition = > 11 ) react even at ?78°C, the reaction of 10 exceeds that of 6 in yield and stereoselectivity. 相似文献
37.
Dr Klaus Rieneck 《European journal of haematology》2006,76(5):451-452
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M L Ganikos C McNeil J B Braslow E B Arkin D Klaus E E Oberley M F White 《Public health reports (Washington, D.C. : 1974)》1994,109(5):626-631
The chasm between the supply and demand of donated organs and tissues continues to grow despite widespread public awareness of transplantation and numerous efforts to educate the public about organ donation. It is fast becoming a significant public health problem in this country. The need for more effective public education is well documented in the literature on transplantation and is a primary objective of organizations in the transplant field. In response to this need, the Division of Organ Transplantation in the Health Resources and Services Administration of the Public Health Service initiated a project to examine the nature and scope of donation education initiatives throughout the country, to identify shortcomings, and to suggest ways the Federal Government could contribute to the effectiveness of public education in organ and tissue donation. The project resulted in the development of a protocol that also is applicable to other health education programs. Its major steps consisted of assessing the status of donation-related public education in the United States, identifying existing needs in donation education by applying principles learned from other public health education programs, and identifying roles that could be assumed to help strengthen the American public''s commitment to organ and tissue donation. These roles, which could be adopted by an transplant-related organization, were as broker of knowledge, producer of educational strategies, energizer through communications research, and catalyst by bringing together other groups. This approach to needs assessment and planning may provide useful insights both for those concerned with transplants and for professionals conducting education campaigns related to other public health issues. 相似文献