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C Hauser-Kronberger GW Hacker K Albegger A Saria WH Muss J Schl?hmicher-Thier O Dietze 《Canadian Metallurgical Quarterly》1994,42(2):89-98
Asymmetry in the face and dentition is a naturally occurring phenomenon. In most cases facial asymmetry can only be detected by comparing homologous parts of the face. The etiology of asymmetry includes: a) Genetic or congenital malformations e.g. hemifacial microsomia and unilateral clefts of the lip and palate; b) Environmental factors, e.g. habits and trauma; c) Functional deviations, e.g. mandibular shifts as a result of tooth interferences. Dental asymmetries and a variety of functional deviations can be treated orthodontically. On the other hand, significant structural facial asymmetries are not easily amenable to orthodontic treatment. These problems may require orthopedic correction during the growth period and/or surgical management at a later point. Patient complaints and desires need to be addressed since they may vary from unrealistic expectations to a lack of concern even in the presence of large deviations. With mild dental, skeletal and soft tissue deviations the advisability of treatment should be carefully considered. 相似文献
74.
S Schlegel R Schl?sser C Hiemke O Nickel A Bockisch K Hahn 《Canadian Metallurgical Quarterly》1996,124(3):285-287
A case of primary cardiac chondrosarcoma in a 41-year-old woman who presented with cardiac tamponade and cardiac intracavitary obstruction is described. The tumor originated from the right atrium and invaded the adjacent right ventricular wall and interatrial septum. Primary cardiac chondrosarcoma is extremely rare, and its clinical, computed tomographic, echocardiographic, and magnetic resonance imaging findings are described. 相似文献
75.
Radiofrequency current catheter ablation of accessory atrioventricular pathways in Ebstein's anomaly
R Cappato M Schlüter C Weiss M Antz DH Koschyk T Hofmann KH Kuck 《Canadian Metallurgical Quarterly》1996,94(3):376-383
BACKGROUND: In patients with Ebstein's anomaly, localization of accessory pathways (APs) may be impeded by abnormal local electrograms recorded along the atrialized right ventricle and by the presence of multiple APs. The impact of these factors on radiofrequency (RF) current catheter ablation of APs has not been evaluated yet. METHODS AND RESULTS: Twenty-one patients with Ebstein's anomaly and reentrant atrioventricular tachycardias underwent electrophysiological evaluation and subsequent attempts at RF catheter ablation. Thirty-four right-sided APs were found, with 30 located along the atrialized ventricle. Local electrograms in this region were normal in 10 patients but fragmented in 11. Fragmented electrograms prevented the clear distinction between atrial and ventricular activation potentials as well as the identification of AP potentials. Right coronary artery mapping was performed in 7 patients. Abolition of all 26 APs was achieved in the 10 patients with normal local electrograms and in 6 of 11 patients with abnormal electrograms. Right coronary artery mapping allowed AP localization and ablation in 5 patients. In the 5 patients with abnormal electrograms and a total of 8 APs, 6 APs could not be ablated. Unsuccessfully treated patients received antiarrhythmic drugs. During 22 +/- 12 months of follow-up, 5 patients had clinical recurrences, including 4 who had undergone a successful RF procedure. CONCLUSIONS: In patients with Ebstein's anomaly and reentrant atrioventricular tachycardias, factors likely to account for failure of RF catheter ablation include an AP located along the atrialized right ventricle and the abnormal morphology of endocardial activation potentials generated in this region. 相似文献
76.
Temperature-gradient gel electrophoresis as a screening tool for polymorphisms in multigene families
C Schl?tterer 《Canadian Metallurgical Quarterly》1995,16(5):722-728
Information about sequence variability between different copies of a multigene family is indispensable for understanding the evolutionary mechanisms acting on multigene families. However, their high copy number has been a major obstacle to systematic analysis. Exemplified by the internal transcribed spacer 1 (ITS1) of the rDNA in Drosophila melanogaster, it is shown how temperature gradient gel electrophoresis (TGGE) can be used to study sequence polymorphisms in a multigene family. Experimental conditions influencing the melting behavior of the ITS1 fragment are discussed as well as discrepancies between observed and calculated melting patterns. 相似文献
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78.
A 34 year-old woman, working with pine wood treated with sodium hydroxide and pyrogallol, developed dermatitis on arms, face and neck. Patch testing showed allergic reaction to colophony and pine wood, but not to sodium hydroxide or pyrogallol. Pine wood contains colophony. Since avoiding pine wood, she has had no further attack of dermatitis. 相似文献
79.
Bayesian decision threshold, detection limit and confidence limits in ionising-radiation measurement
Weise K Hübel K Rose E Schläger M Schrammel D Täschner M Michel R 《Radiation protection dosimetry》2006,121(1):52-63
Based on Bayesian statistics and the Bayesian theory of measurement uncertainty, characteristic limits such as the decision threshold, detection limit and limits of a confidence interval can be calculated taking into account all sources of uncertainty. This approach consists of the complete evaluation of a measurement according to the ISO Guide to the Expression of Uncertainty in Measurement (GUM) and the successive determination of the characteristic limits by using the standard uncertainty obtained from the evaluation. This procedure is elaborated here for several particular models of evaluation. It is, however, so general that it allows for a large variety of applications to similar measurements. It is proposed for the revision of those parts of DIN 25482 and ISO 11929 that are still based on conventional statistics and, therefore, do not allow to take completely into account all the components of measurement uncertainty in the calculation of the characteristic limits. 相似文献
80.
Yi‐Jun Xu Gisela Weinberg Xi Liu Olaf Timpe Robert Schlögl Dang Sheng Su 《Advanced functional materials》2008,18(22):3613-3619
Nanoarchitecturing of carbon nanospheres onto the surface of activated carbon (AC) gives birth to a new composite carbon material that features a hierarchical structure with macro‐ and nanometer dimensions of the respective carbon components and exhibits a remarkably enhanced adsorption capability for heavy‐metal ions ( and Fe3+) from aqueous solution as compared to AC. Thus, we first propose that nanoarchitecturing of AC can be utilized not only as a flexible method for the synthesis of novel, hybrid, nanostructured composite carbon materials but also as a new and “green‐route” strategy for functionalization of the surface of AC in an effective manner. Hence, there is scope for a possible new concept in the functionalization of industrial AC for specific applications. 相似文献