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The purpose of this study was to evaluate the properties of a novel inorganic xenogenic bone substitute, calcinated antler cancellous bone (CACB). Physicochemical properties of CACB including surface morphology, phase composition, chemical bond structure, Ca/P ratio and porosity were characterized by scanning electron microscopy, X-ray diffraction spectroscopy, Fourier-transform infrared spectroscopy, inductively coupled plasma-atomic emission spectroscopy and nitrogen adsorption analysis, and were found to closely resemble calcinated human cancellous bone. The bone defect repair efficacy of CACB was evaluated in comparison with commercially available bone substitutes (Bio-Oss®) within rabbit mandible defects. The gross observation, micro-CT and histology analysis data demonstrated that CACB was efficacious for bone regeneration, and was comparable with Bio-Oss® bone substitute in inducing neovascularization and osteogenesis within the mandible defects. CACB can therefore serve as a safe, renewable, and sustainable source of bone graft material, but without the ethical issues pertaining to animal welfare.  相似文献   
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To establish the prognostic factors for primary intraosseous squamous cell carcinoma we designed a retrospective study of patients treated in the head and neck department of a tertiary referral centre in China from 2010–2015. We collected clinical, radiological, and histopathological data from 36 patients treated during the given time period, among which 34 were followed up. There were 22 male and 12 female patients, 13 of whom gave a history of smoking tobacco and four who drank alcohol. All 34 patients were treated by segmental mandibulectomy and neck dissection. Nine had cervical lymph node metastases on histopathological examination, and none had invaded surgical margins. Twenty-eight were treated with radiotherapy postoperatively. During follow up nine died of locoregional recurrence or metastases. Specific factors such as cervical lymph node metastases were related to a greater likelihood of locoregional recurrence. Patients who drank alcohol were also more likely to develop metastases postoperatively. Tumours more than 4 cm in size were significantly associated with reductions in locoregional control and survival.  相似文献   
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Diagnosis of invasive pulmonary aspergillosis (IPA) is a challenging process in immunocompromised patients. Galactomannan (GM) antigen detection in bronchoalveolar lavage (BAL) fluid is a method to detect IPA with improved sensitivity over conventional studies. We sought to determine the diagnostic yield of BAL GM assay in a diverse population of immunocompromised patients. A retrospective review of 150 fiberoptic bronchoscopy (FOB) with BAL for newly diagnosed pulmonary infiltrate in immunocompromised patients was performed. Patient information, procedural details and laboratory studies were collected. BAL and serum samples were evaluated for GM using enzyme‐linked immunoassay. Of 150 separate FOB with BAL, BAL GM was obtained in 143 samples. There were 31 positive BAL GM assays. In those 31 positive tests, 13 were confirmed as IPA, giving a positive predictive value of 41.9%. There was one false negative BAL GM. Of the 18 false positive BAL GM, 4 were receiving piperacillin–tazobactam and 11 were receiving an alternative beta‐lactam antibiotic. BAL GM assay shows excellent sensitivity for diagnosing IPA. There was a significant number of false positive BAL GM assays and several of those patients were receiving beta‐lactam antibiotics at the time of bronchoscopy.  相似文献   
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Clinical Oral Investigations - There is significant evidence that articaine and lidocaine buccal injections alone are sufficient for painless extraction of maxillary teeth. The aim of this study...  相似文献   
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