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81.
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Selective luteinizing hormone deficiency due to mutations in the luteinizing hormone beta-subunit gene (LHB) is a rare cause of hypogonadism. We describe the clinical features of a consanguineous family in which three siblings, two men and one woman, had hypogonadism related to isolated luteinizing hormone deficiency. These subjects have a newly discovered homozygous mutation of a 5' splice site in LHB: IVS2+1G-->C. This mutation disrupts the splicing of messenger RNA (mRNA), generating a gross abnormality in the processing of the luteinizing hormone beta-subunit mRNA, which abrogates the secretion of luteinizing hormone. We also determined that the female phenotype of this LHB mutation is characterized by normal pubertal development, secondary amenorrhea, and infertility.  相似文献   
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Objective:

To evaluate the role of socioeconomic variables and self-perceived oral health in the polarization of caries among adolescents in Santa Bárbara D''Oeste, Brazil.

Material and Methods:

Cross-sectional study. Sampling was randomized and sample size was defined according to WHO criteria. Two hundred and seventy seven adolescents (15 to 18 year-old) were examined by five trained examiners that assessed DMFT index according to WHO criteria. Self-perceived oral health, access to dental services and socio-demographic variables were self-reported. Student''s t tests, chi-square tests, and multivariate logistic regression (with significant caries index (SiC) as the outcome), were performed.

Results:

Mean DMFT was 5.48 (±4.22) and the proportion of "caries free" subjects was 15.5%. Mean DMFT (9.71±2.85) and mean D (1.67±2.18) of SiC positive subjects were significantly higher than mean DMFT (2.88±2.17) and mean D (0.45±0.87) of SiC negative subjects (p<0.0001). Mean D of white (0.76±1.51) was significantly smaller than mean D of non-white subjects (1.32±2.01). The only variable independently associated with the "SiC positive" outcome was "report of toothache within six months prior to the study" [OR=1.83 (95%CI 1.08 to 3.12)], p<0.001.

Conclusion:

SiC was associated with "report of toothache" but not with sociodemographic variables in the studied population.  相似文献   
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Tonsillolith is a rare dystrophic calcification as a result of chronic inflammation of the tonsils. Three asymptomatic cases of tonsillolith are reported, incidentally discovered through panoramic radiographs, which showed different sizes of radiopaque images, varying from 2 to 5 mm; cases I and III images did not overlap the mandible ramus, which led to a probable diagnosis of soft tissue calcification. Case II had radiopaque unilateral images, with osseous tissue density, overlapping the mandibular ramus, leading to a benign intra-osseous lesion, which was considered as differential diagnosis. No symptoms were reported in any case. Only case I had clinical characteristics, showing highly consistent white plaques partially visible through the mucosa. Computed tomography of the maxillofacial region/head and neck were requested to find out the exact location of these images, since most of the overlapping radiopaque images in the mandibular ramus were very similar to intra-osseous abnormalities. The computed tomography showed hyperdense images in the palatine tonsils, confirming the diagnosis of tonsillolith. The patients are currently under follow-up. No treatment is required if there is no symptom. In conclusion, tonsillolith might show images on panoramic radiographs similar to intra osseous abnormalities. The diagnosis is relatively easy when computed tomography is requested, although the images are not pathognomonic. Therefore, clinicians should consider other pathologies as differential diagnosis.  相似文献   
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Background: Maxillofacial defects caused by cancer treatment are a huge problem affecting the quality of life of patients. Some of these deformities are minimized using facial epitheses, which need some additional retention devices like glasses or skin adhesives. The use of extraoral fixtures as bone anchorage was introduced many years ago and since then many patients were rehabilitated with better results. Purpose: Because of poor bone conditions, for example, irradiated bone, the success rate of extraoral implants is less than in the oral cavity, causing difficulties to rehabilitation. One possible cause of fixture failure could be the poor primary stability achieved in some cases, hence, with an increased bone contact implant stability and survival could be improved. The present report discusses possibilities to use extraoral fixtures with a modified surface structure. Materials and Methods: A new porous surfaced Brazilian extraoral implant (MasterExtra®, Conexão, Sistema de Próteses, São Paulo, Brazil) was used. A bone transplant from the iliac crest was taken to make it possible to insert at least three extraoral implants for an auricle epithesis. Clinical evaluation and resonance frequency analysis (RFA) measurements were performed during the course of the treatment. Results: Eight months after grafting, four fixtures were inserted. Three fixtures were used for connection of an auricular epithesis. RFA measurements did show high initial values and the values remained stable during the course of the treatment and at later checkups. Conclusion: Porous fixture is a good option in areas where the bone is compromised. RFA is a good tool also in the clinical setting to evaluate immediate and long‐term stability of extraoral fixtures.  相似文献   
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This study investigated the effects of 670-nm indium gallium phosphide (InGaP) and 830-nm gallium aluminum arsenide (GaAlAs) laser therapy on second-degree burns induced on the back of Wistar rats. Sixty-three male Wistar rats were anesthetized, and second-degree burns were made on their back. The animals were then divided randomly into three groups: control (C), animals treated with 670-nm InGaP laser (LIn), and animals treated with 830-nm GaAlAs laser (LGa). The wound areas were removed after 2, 6, 10, 14, and 18 days of treatment and submitted to structural and morphometric analysis. The following parameters were studied: total number of granulocytes and fibroblasts, number of newly formed blood vessels, and percentage of birefringent collagen fibers in the repair area. Morphometric analysis showed that different lasers 670-nm InGaP and 830-nm GaAlAs reduced the number of granulocytes and an increase of newly formed vessels in radiated lesions. The 670-nm InGaP laser therapy was more effective in increasing the number of fibroblasts. The different treatments modified the expression of VEGF and TGF-β1, when compared with lesions not irradiated. The different types of light sources showed similar effects, improved the healing of second-degree burns and can help for treating this type of injury. Despite the large number of studies with LLTI application in second-degree burns, there is still divergence about the best irradiation parameters to be used. Further studies are needed for developing a protocol effective in treating this type of injury.  相似文献   
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