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PURPOSE: The purpose of this pilot study was to test a new Le Fort I internal distraction device. PATIENTS AND METHODS: A new internal Le Fort I distraction device designed by 1 of the authors was used in 3 patients with cleft lip and palate and severe maxillary hypoplasia who needed maxillary advancements in excess of 12 mm. Presurgical planning used CASSOS (SoftEnable Technology, Ltd, Hong Kong SAR, China) prediction tracing software and a stereolithographic model to calculate the distraction vector. The distractors were pre-bent and installed on the stereolithographic model and activated to advance the maxilla. Surgery was performed in a conventional manner, and distraction was started after a 7-day latency phase at the rate of 1 mm/day and continued until the presurgical plan was achieved. The distractor was removed after a 3-month consolidation phase. Cephalometric radiographs were taken at the completion of each phase. RESULTS: This new Le Fort I internal distraction device successfully distracted the maxillae as planned in all 3 patients. At the end of the distraction phase, the maxillary advancement was measured at 15.8 mm, 15.8 mm, and 13.5 mm, respectively. In each patient, a clockwise rotation of the maxilla was observed with a tendency to a posterior open bite. Postoperative radiographs also showed that the actual distraction vectors differed from the planned vectors. After the consolidation phase, radiographs showed a relapse of 2.6 mm, 0 mm, and 5.0 mm, respectively. There was no further relapse on 3-month follow-up radiographs. Each case showed radiographic evidence of excellent new bone formation at the osteotomy sites. CONCLUSION: The new Le Fort I internal distraction device produced the necessary advancement in all 3 patients. The study also showed that the actual distraction vector differed from the planned vector. This discrepancy was caused by a clockwise rotation of the maxilla during the distraction. Finally, the study showed a variable relapse rate not previously reported in maxillary distraction.  相似文献   
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Four poorly differentiated malignant lesions occurred in a 60-year-old Chinese male in the nasal cavity, submandibular gland, a lymph node in the neck, and the mandible. These malignant lesions developed within an 8-year period and each showed distinctive histological features. Among these malignant lesions, the neoplasm in the submandibular gland presented variegated histological and immunohistochemical (IHC) features and posed a diagnostic challenge in interpretation. Based on microscopic and IHC findings, we believe the diagnosis of teratocarcinosarcoma is justified for the submandibular neoplasm and the metastasis in the lymph node. The pathological features and diagnoses of these malignant lesions are discussed.  相似文献   
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Background: Noncompliance with instructed saliva sampling times in ambulatory settings can compromise resulting cortisol findings.Purpose and Methods: Here, the impact of noncompliance on the cortisol awakening response (CAR), an established marker for hypothalamic-pituitary-adrenal axis activity, was examined over 3 sampling days in middle- and older-age participants in the Chicago Health, Aging, and Social Relations Study.Results: Noncompliant participants had a significantly lower cortisol rise after awakening (assessed by an awakening sample and a 30-min after awakening sample) on 2 of the 3 sampling days (Day 1, ns; Days 2 & 3, ps<.02). Furthermore, social support measured by the Interpersonal Support Evaluation List correlated negatively with the number of “noncompliant” samples (r=−.19, p<.05), indicating that participants reporting more social support had more “compliant” samples.Conclusion: The results confirm that nonadherence to saliva sampling in ambulatory settings can exert a significant impact on the resulting CAR. Furthermore, the data raise the idea that the extent of nonadherence might be systematically associated with psychosocial factors like social support. For future studies on the relationship between CAR and psychological factors, we therefore recommend controlling for saliva sampling adherence because noncompliance might be systematically associated with the phenomenon being investigated. Funding was provided by the National Institute of Aging Grant No. PO1 AG18911 and the John Templeton Foundation. Brigitte M. Kudielka was supported by grants from the German Research Foundation (DFG grant KU 1401/3-1 and KU 140/4-1).  相似文献   
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