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A new surgical technique for the treatment of recurrent temporomandibular joint subluxation or dislocation is described. Following a horizontal osteotomy and down-fracture of the articular eminence an inter-positional bovine cartilage xenograft is inserted in order to augment the vertical height of the eminence. The procedure combines simplicity with minimal post-operative morbidity. The increase in eminence height is both predictable and stable.  相似文献   
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We report a case of severe carcinoma-associated dermatomyositis which, having shown no response to conventional treatment, improved markedly within 48 h of plasmapheresis. We believe that this is the first time that dermatomyositis associated with an advanced carcinoma has been reported to respond in this way. Dermatomyositis can prove extremely difficult to treat and sometimes fails to respond even to very high doses of steroids and immunosuppressants. There is currently only a single report of the use of plasmapheresis in adult dermatomyositis. We therefore wish to support the findings of Dau and draw attention to the value of this therapeutic option in refractory dermatomyositis.  相似文献   
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Self-mutilation by lip chewing is an uncommon problem, but may result in severe mutilation, infection and loss of tissue, with associated scarring. Many modalities of treatment have been proposed in the literature with variable success and morbidity to the patient. Alternative techniques involving orthognathic surgery to create an anterior open bite are described which may result in cessation of self-mutilation. A case is presented with a 13-year follow-up, the anterior open bite is still present, and no recurrence of self-mutilation.  相似文献   
7.
Platelets from seven normal subjects were fractionated on continuous Percoll density gradients and low density (LD), intermediate, and high density (HD) platelets were prepared for transmission electron microscopy followed by computerised morphometric analysis. Normal ultrastructural appearance and discoid shape were preserved by incubation of the platelets in nutrient medium at 37 degrees C immediately before fixation. HD platelet sections had a larger mean cross-sectional area but a lower ratio of the major to the minor axis compared to LD platelet sections. HD platelets contained more alpha granules, dense granules and mitochondria per square micron of section area than LD platelets. The percentage of section area occupied by open canalicular system was greater in the LD platelets while the percentage area occupied by glycogen fields was over ten-fold higher in the HD platelets. The mean cross-sectional areas of individual alpha granules and dense granules increased with density while the opposite trend was found for mitochondria. It is suggested that these ultrastructural differences mainly arise during thrombopoiesis and may indicate some functional specialization among platelets.  相似文献   
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PURPOSE: Systematic evaluation of the Karapandzic flap in the reconstruction of lip defects after ablative surgery. PATIENTS AND METHODS: Patients who had a Karapandzic flap to reconstruct lip defects were analyzed with reference to demographic details, histology and location of the tumor, and dimensions of resection. The functional aspects of the reconstruction were assessed in terms of the size of the oral stoma, preservation of oral competence, and facial expression, in addition to speech, diet and ease of cutlery, and denture usage. The esthetic outcome was assessed with a 4-point scale and in addition the symmetry of the commissure at rest and function, preservation of the philtrum, and lip projection also were assessed. The complications were noted. RESULTS: Seven patients underwent Karapandzic flap reconstruction (4 males, 3 females) with an age range of 43 to 98 years. Three tumors were located in the upper lip, 4 in the lower lip, and there were 5 squamous and 2 basal cell carcinomas. The lip defects ranged from 40% to 75% of the lip circumference. The oral stoma was of a reduced circumference in all cases but did not lead to any functional compromise in terms of oral competence, facial expression, speech, diet, denture and cutlery usage, and sensation. There were no wound complications in our series. The esthetic outcome was considered excellent/good in 85% of cases. The commissure was symmetrical in all except 1 patient, the philtrum was preserved in all cases of lower lip reconstruction, and the projection of the lip was reduced in edentulous patients. CONCLUSIONS: The Karapandzic flap is a reliable technique that offers consistently good functional and esthetic outcomes after reconstruction of lip defects.  相似文献   
9.
Population studies of the fragile X: a molecular approach.   总被引:11,自引:1,他引:11       下载免费PDF全文
The fragile X mutation can now be recognised by a variety of molecular techniques. We report a pilot screening survey of a population of children with mental impairment in which we used Southern blotting methods to detect the fragile X mutation, augmented by cytogenetic studies on children whose phenotype suggested a possible chromosome abnormality. There were 873 children with special educational needs in our survey and 310 fulfilled our criteria for testing. A sample was obtained from 254, of whom four were found to have a full fra(X) mutation (delta L) and none to have a premutation. The number of CGG repeats in our population of X chromosomes was measured by PCR analysis and the genotype at the closely linked polymorphic locus FRAXAC1 established. The distribution of CGG repeat numbers was very similar to that of the control population reported by Fu et al and the distribution of FRAXAC1 alleles almost identical to that of the control population reported by Richards et al. Among the non-fragile X chromosomes, we found a very significant correlation between the size of the CGG repeat and the FRAXAC1 genotype. There was a dearth of A and D genotypes in subjects with a small number of CGG repeats and an excess of the A genotype in those with a large number of CGG repeats. These observations are considered in the light of the reported disequilibrium between the A (and possibly also the D) genotype and the fra(X) mutation.  相似文献   
10.
Instability of the FMR1 repeat, commonly observed in transmissions of premutation alleles (55–200 repeats), is influenced by the size of the repeat, its internal structure and the sex of the transmitting parent. We assessed these three factors in unstable transmissions of 14/3,335 normal (~5 to 44 repeats), 54/293 intermediate (45–54 repeats), and 1561/1,880 premutation alleles. While most unstable transmissions led to expansions, contractions to smaller repeats were observed in all size classes. For normal alleles, instability was more frequent in paternal transmissions and in alleles with long 3′ uninterrupted repeat lengths. For premutation alleles, contractions also occurred more often in paternal than maternal transmissions and the frequency of paternal contractions increased linearly with repeat size. All paternal premutation allele contractions were transmitted as premutation alleles, but maternal premutation allele contractions were transmitted as premutation, intermediate, or normal alleles. The eight losses of AGG interruptions in the FMR1 repeat occurred exclusively in contractions of maternal premutation alleles. We propose a refined model of FMR1 repeat progression from normal to premutation size and suggest that most normal alleles without AGG interruptions are derived from contractions of maternal premutation alleles.  相似文献   
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