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31.
Imaging is an essential diagnostic tool in reconstructive middle ear surgery, especially in pre-operative planning. Due to ongoing improvement of imaging quality and development of new imaging techniques like e.g. rotational tomography (RT) post-operative follow-up and immediate evaluation of surgical results may become more important. The aim of this experimental study was to evaluate RT as a new tool for postoperative determination of middle ear anatomy and implant position in temporal bones. RT was performed in ten temporal bone specimen after insertion of different middle ear prostheses concerning material, shape and length (PORP; TORP; Stapes piston). An implantable hearing device (Symphonix Soundbridge®) was also implanted and visualized. For comparison some specimen additionally underwent conventional computed tomography (CT), including the newest technology. Characterization of anatomical structures of the temporal bone using RT was of comparable quality to conventional CT-scans in all investigated specimen while requiring approximately 30% of the CT’s irradiation exposure. Unlike CT the RT showed almost no problems due to metallic artefacts of the implanted prostheses. Furthermore RT enabled a 3-dimensional view of the temporal bone and angle determination of inserted prostheses towards the tympanic membrane and/or the malleus handle. Detailed imaging of the prostheses allowed determination of shape, material and localization within the specimen’s reconstructed middle ear. The new imaging technique of RT allows precise presentation of anatomical structures and middle ear implants in temporal bones. Following these experimental results it will be our future work to evaluate this method in clinical practise.  相似文献   
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Melphalan and cyclophosphamide, cytostatics used for cancer therapy, were investigated for their ability to induce morphological transformation of embryonic cells of the golden hamster and to evoke structural chromosome aberrations. The antimitotic action of both drugs was also investigated. Cyclophosphamide, under conditions in which it did not produce either structural chromosomal aberrations or exerted cytotoxic action, induced morphological transformation of hamster cells. Under the experimental conditions melphalan induced morphological transformation of hamster cells at concentrations not inducing chromosomal aberrations.  相似文献   
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Summary The management of displaced intracapsular fractures of the hip is still controversial because of the high incidence of complications after internal fixation or hemiarthroplasty. To avoid some of these complications we have used primary total hip replacement for independently mobile patients over 65 years of age.Of 49 patients who were interviewed an average of 4.6 years after total hip replacement, 81.6% had excellent or good results as assessed by the Harris Hip Score. At that time two hips had been revised and another converted to Girdlestone due to deep infection. The survival of the prostheses was at 5 years 91.3%.It is concluded that total hip replacement is an established method of management for a selected group of patients with this injury, but further prospective studies are needed in order to define the groups of patients that benefit the most.  相似文献   
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Malakoplakia of the testis presenting as painless enlargement of the testis in an 80-year-old man is described. The literature is reviewed.  相似文献   
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Summary In three consecutive cases of giant left sided paraclinoid aneurysms we employed an endovascular retrograde suction decompression technique in combination with intra-operative angiography. A double-lumen balloon catheter was placed in the left internal carotid artery by the transfemoral route. After balloon inflation and placement of a temporary clip distal to the aneurysm blood was aspirated and the aneurysm collapsed. Thus further dissection of the aneurysm could easily be achieved and clips could be placed. Afterwards real-time digital subtraction angiography was performed. Intra-operative angiography led to clip repositioning in all cases either due to a clip induced stenosis of the parent vessel, or because of incomplete aneurysm obliteration. Afterwards successful clipping could be confirmed in all cases. Outcome was excellent in one case, good in the other. The third case, extremely complicated by an accompanying craniopharyngioma, showed a satisfactory outcome, but presented new neurological deficits.  相似文献   
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Heart failure is a complex clinical syndrome. There is evidence for a genetic contribution to the pathophysiology of heart failure. Considering the fundamental role of neurohormonal factors in the pathophysiology and progression of cardiac dysfunction and hypertrophy, variants of genes involved in this system are logical candidate genes in heart failure. In this report, genetic polymorphisms of the major neurohormonal systems in heart failure will be discussed. Studies on polymorphisms of the renin-angiotensin-aldosterone system (RAAS), adrenergic receptor polymorphisms, endothelin (receptor) polymorphisms, and a group of miscellaneous polymorphisms that may be involved in the development or phenotypic expression of heart failure will be reviewed. Research on left ventricular hypertrophy is also included. The majority of genetic association studies focused on the ACE I/D polymorphism. Initial genetic associations have often been difficult to replicate, mainly due to problems in study design and lack of power. Promising results have been obtained with genetic polymorphisms of the RAAS and sympathetic system. Considering the evidence so far, a modifying role for these polymorphisms seems more likely than a role of these variants as susceptibility genes. Besides the need for larger studies to examine the effects of single nucleotide polymorphisms and haplotypes, future studies also need to focus on the complexity of these systems and study gene-gene interactions and gene-environment interactions.  相似文献   
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