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51.
Genetic studies on spontaneous mouse mutants with hearing defects have provided important insights into the function of genes expressed in inner ear hair cells. Here we report on our genetic analyses of the deaf mutants varitint-waddler (Va) and jerker (Espnje). A high-resolution genetic map localizes VaJ to a 0.14 ± 0.08 cM region between D3Mit85 and D3Mit259 on distal chromosome 3. By comparative mapping, the human ortholog resides at 1p22.3 between markers D1S3449 and D1S2252. To study the effect of different genetic backgrounds on the hearing phenotype, Espnje and VaJ were crossed to various inbred strains. Auditory-evoked brainstem response tests on F2 progeny demonstrate that expression, inheritance, and penetrance of the hearing phenotype are solely controlled by the mutant allele. To test for a genetic interaction between Espnje and Cdh23v, auditory function was analyzed in double heterozygotes; no significant increases of thresholds of sound pressure levels were observed. The results establish the framework for cloning the Va gene and provide valuable insights into the genetics of deafness mutations in the mouse.  相似文献   
52.
Abstract Surgical treatment of proximal humeral fractures still remains a challenge. This is primarily due to the fact that sufficient implant fixation in humeral head fractures is often not achieved due to substantial bone tissue loss with increasing age. In the last few years the locking plates and locking nails have been introduced into clinical practice with varying results. The biomechanical studies have focused on locking plate osteosynthesis as well. The following paper focuses on bone quality, biomechanical studies and biology of proper osteosynthesis and reviews the most recent literature.  相似文献   
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Background  

For patients suffering of recurrent breast cancer within the irradiated breast, generally mastectomy is recommended. The normal tissue tolerance does not permit a second full-dose course of radiotherapy to the entire breast after a second breast-conserving surgery (BCS). A novel option is to treat these patients with partial breast irradiation (PBI). This approach is based on the hypothesis that re-irradiation of a limited volume will be effective and result in an acceptable frequency of side effects. The following report presents a single center experience with intraoperative radiotherapy (IORT) during excision of recurrent breast cancer in the previously irradiated breast.  相似文献   
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The presence of blood in the ejaculate is called hematospermia or hemospermia. While often perceived as a symptom of little significance, hematospermia can cause great concern to men who experience it. We report an unusual case of hematospermia associated with pelvic arteriovenous malformation (AVM). A 60-year-old man who visited our hospital complaining of hematospermia and pollakisuria was found to have AVM and aneurysmal changes in the left side of the pelvis using computed tomography (CT). The patient was treated with steel coil embolization of the left inferior gluteal artery, and after the procedure the hematospermia and pollakisuria remained absent without flare-ups.  相似文献   
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The incidence of stonestreet formation after extracorporeal shock wave lithotripsy (ESWL) rises with increasing stone burden. However, stonestreet after ESWL is often experienced even in stones smaller than 20 mm. To examine whether the non-contrast helical computed tomography (CT) data could predict stonestreet formation in these stones, 53 radiopaque stones of 5-20 mm treated with ESWL were evaluated. Maximal dimension was measured on plain radiograph. From an attenuation value histogram graphed from the CT data, total stone volume and mean attenuation value were calculated. Seven stonestreets longer than 25 mm developed. There was no significant difference in maximal dimension and total stone volume between stones that did and stones that did not develop stonestreet. Mean attenuation value was the sole significant predictive factor. Application of mean attenuation value with cut-off level of 650 HU would anticipate stonestreet formation with a sensitivity of 85.7% and a specificity of 71.7%. The estimated risk of stonestreet formation is high in the treatment of stones with higher mean attenuation value.  相似文献   
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Haemangiomas are the most common tumours of infancy. They typically proliferate then involute with considerable variation as regards to their rates of proliferation and involution. Haemangioma of the nasal tip is a lesion of special characteristics. During proliferation, it expands, contracts and deviates the nasal cartilages. Particularly, it regresses slowly and frequently involutes incompletely. That is why excision of the lesion is frequently suggested. The present study was conducted to evaluate open rhinoplasty after initial non-excision treatment modalities namely, intra-lesional corticosteroid injections and laser treatment, as a protocol of treatment for nasal tip haemangiomas. Twelve patients with nasal tip haemangiomas were included in the present study. Patients of both sexes, of different ages, with deep and mixed haemangiomas were studied. Disfigurement was the constant presenting symptom. Initial non-excision treatment reported different responses as denoted by the regression of the lesions’ size. Haemangiomas constantly extended between the medial crura of the alar cartilages as noted by the constant widening of the columella pre-operatively and the obvious separation of the nasal cartilages intra-operatively. This separation was constantly found to require approximation by sutures. The results of the present study concluded that whenever an early presentation with nasal tip haemangioma could be established, initial non-excision treatment followed by open rhinoplasty could be a useful protocol of treatment. Within the limitations of the present study, this protocol could achieve an early, safe and effective treatment for nasal tip haemangiomas with provisionally acceptable cosmetic outcomes so far.  相似文献   
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