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Facial hemiatrophies are anomalies of the first branchial arch and affect one in 4000-5000 newborns. Bone distraction is the technique of choice for the treatment of these dysmorphoses. Mandibular osteodistraction requires prior determination of the characteristics of the distraction vector whose three components will serve to activate the distractor. The patient, aged 5 years, presented with a right facial hemiatrophy, Grade IB according to the classification of Pruzansky. Tomodensitometric acquisition was obtained with a CT scanner. Software specifically designed for this application allows segmentation of the anatomical elements by a region-growing algorithm. The 3D representation of each element is added to a 3D scene, in which are placed the built-up landmarks necessary for the surgical simulation after 3D cephalometric analysis. The surgical cleavage plane is oriented according to the surgeon's requirements while preserving the predominant anatomical elements. The software allows performance of rotations and translations of the bone segments rendered independently from the cleavage plane. The distances and angles covered during the virtual movement are measured at its conclusion. The aim of moving the bone segments is to render the mandibular occlusion plane parallel to the reference occlusion plane. The vertical growth of the maxilla is realized by secondary recuperation. The distractor used was of an external multidirectional type allowing elongation of the mandibular ramus and mandibular corpus, closure of the goniac angle, and lateralization or medialization of the ramus. On the 15th day, the mandibular angle was reduced by 10 degrees, which allowed closure of the anterior gap and recentering of the incisive areas by a half-cuspid. The patient presented with a complex bone deficit in the three spatial directions, which allowed the development of software for modeling the distraction. Other clinical cases will be necessary to validate this 3D imaging-based technique.  相似文献   
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Introduction –  The relative frequencies of different ataxias vary among different ethnic and geographic groups. The aim of this study was to examine patients with cerebellar ataxia and find the occurrence of autosomal dominant and recessive cerebellar ataxias in the population of the southern and eastern parts of Norway and estimate its prevalence.
Materials and methods –  Probands were systematically tested for spinocerebellar ataxia 1, 2, 3, 6 and Friedreich's ataxia. A total of 94 patients with ataxia were assessed.
Results –  We registered 60 patients from 39 unrelated families with hereditary ataxias. One family with SCA2 (two patients), one family with Friedreich's ataxia (two patients), two patients heterozygote for Friedreich's ataxia and one metabolic ataxia were identified.
Conclusions –  We have few Friedreich's ataxia and SCA 1,2,3 and 6 in our population. Prevalence in Oslo County was estimated at 2.2/100,000 for autosomal recessive and 3.0/100,000 for autosomal dominant ataxia, respectively.  相似文献   
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The severely of skin loss and the options of resurfacing is determined by taking into account the following factors. 1) The size & location of the defect, 2) The depth of the defect and the quality of the tissue bed, 3) The extent of exposed vital structures, 4) The associated bone and other tissues injuries, 5) The availability of donor skin flap. The size of the defect is the most important factor in choosing a resurfacing option. The size can be categorized into small, medium and large. A small defect is one that is less than 5 cm2 in size, a medium defect is between 5 to 15 cm2, and a large defect is greater than 15 cm2. Local flaps are usually sufficient to cover small defects <5 cm2. These are advancement flaps or rotation and transposition flaps. Regional flaps are indicated to resurface these medium‐sized defects 5 to 15 cm2. The donor is within the same region of the hand, from one of the digits or from dorsum and palmar surfaces of the hand. It is usually based on vascular or NV pedicles. Large defects >15 cm2 will need larger flaps for coverage. These large flaps are pedicled distant flaps and free flaps. In these severe injuries, there is usually associated bone and soft tissues injuries. These injuries can be reconstructed as a single stage combined reconstruction or multi‐staged reconstructions. The resurfacing should always be given priority.  相似文献   
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Obesity related cardiovascular disease has assumed epidemic proportions and it is important that we properly understand how hormones of metabolism influence cardiac function. Over the last 15 years a multitude of factors have been discovered that appear to play significant roles in energy balance and metabolism, markedly changing our view of fat and GI cells and their dynamic control and regulation of metabolism. This presentation will focus on how three recently discovered hormones Ghrelin, Leptin and Resistin may directly influence cardiac function. Ghrelin is predominately produced and secreted from the X/A cells of the stomach and studies suggest it can act as a cardioprotective agent. However, Ghrelin also acts to constrict the coronary arteries, which places potential limitations upon its therapeutic use. Leptin is produced by adipose tissue in proportion to fat deposition and appears to drive satiety signals in the body. In contrast, Leptin appears to antagonise cardiac function and it may drive the development of hypertension by impairing renal pressure natriuresis and down regulating endothelium derived vasorelaxant factors. The third factor, Resistin, was originally described from rat adipose tissue and was shown to impair insulin action and glucose control. In humans however, Resistin is primarily produced in inflammatory cells such as monocytes and macrophages. Resistin worsens the recovery of the heart from a period of experimental ischemia and promotes the release of inflammatory agents such as tumour necrosis factor‐alpha. Such actions may be partially responsible for the observed insulin resistance after cardiac surgery.  相似文献   
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