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OBJECTIVES: Measurement of cortical thickness and subjective assessment of cortical porosity on panoramic radiographs are methods previously reported for diagnosing osteoporosis. The aims of this study were to determine the relative efficacy of the mandibular cortical index and cortical width in detecting osteoporosis, both alone and in combination, and to determine the optimal cortical width threshold for referral for additional osteoporosis investigation. STUDY DESIGN: Six hundred seventy-one postmenopausal women 45 to 70 years of age were recruited for this study. They received dual energy x-ray absorptiometry (DXA) scans of the left hip and lumbar spine (L1 to L4), and dental panoramic radiographic examinations of the teeth and jaws. Three observers separately assessed the mandibular cortical width and porosity in the mental foramen region of the mandible. Cortical width was corrected for magnification errors. Chi-squared automatic interaction detection analysis (CHAID) software was used (SPSS AnswerTree, version 3.1, SPSS Inc., Chicago, IL). RESULTS: Chi-squared automatic interaction detection analysis showed that the cortical porosity was a poorer predictor of osteoporosis than mandibular cortical width. For the 3 observers, a mandibular cortical width of <3 mm provided diagnostic odds ratios of 6.51, 6.09, and 8.04. The test is therefore only recommended in triage screening of individuals by using radiographs made for purposes other than osteoporosis. CONCLUSION: When evaluating panoramic radiographs, only those patients with the thinnest mandibular cortices (i.e., <3 mm) should be referred for further osteoporosis investigation.  相似文献   
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CASE REPORT: The reported female patient underwent sub-total resection of an intra-medullary cervicothoracic astrocytoma classified as WHO grade II in 1984 at the age of 18 months and received local irradiation. In 1989, a local recurrence was diagnosed and a partial resection was performed. Sixteen years later, a small recurrent cervicothoracic tumour was found and spinal seeding to the equine nerve roots and the left cerebellar cortex was apparent on MRI. The patient was implanted with a ventriculoperitoneal shunt for a pseudo-tumour cerebri producing papilloedema, which eventually lead to amaurosis. After an extended biopsy, the invasive lumbosacral tumour was classified as glioblastoma multiforme. Two months later, the patient died after rapid progression of the caudal cranial nerve dysfunction. DISCUSSION AND CONCLUSION: Anaplastic progression and dissemination of spinal astrocytomas even two decades after initial diagnosis and treatment are rare. Therapies and diagnostic follow-up strategies are discussed.  相似文献   
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OBJECTIVE  Increased plasma concentrations of GH and increased GH responses to provocative stimuli are reported in patients with poorly controlled type I diabetes and are suggested to be related to complications. Our aim was to investigate GH concentrations in moderately controlled patients.
PATIENTS AND MEASUREMENTS  We have investigated IGF-I concentrations and fasting GH concentrations and the response to 1 μg/kg body weight GH-releasing hormone (GHRH) intravenously and/or to 150 μg clonidine intravenously in 77 moderately controlled patients with type I diabetes and in 46 healthy controls.
RESULTS  Median HbA1c in the patients was 8.5% (upper level of normal 6.3%). Fasting GH and GH concentrations after the administration of GHRH were not significantly different in patients with type I diabetes compared with normal controls. Fasting and stimulated GH concentrations after the administration of clonidine were significantly higher in the patients, but this could be explained by their lower age and body mass index compared with controls. In controls but not in patients there was a negative correlation between GH and glucose concentrations. IGF-I was significantly lower in patients with diabetes than in controls, even after correction for age, body mass index and sex.
CONCLUSIONS  Patients with moderately controlled type I diabetes mellitus have normal baseline and stimulated GH concentrations after the administration of GHRH or clonidine compared with healthy controls, when corrected for age, body mass index and sex. However, these 'normal' GH concentrations must be considered inappropriately high in view of the hyperglycaemia in these patients. The low plasma IGF-I concentrations might be responsible for the GH over-production.  相似文献   
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The results of this single-blind randomised trial comparing adrenaline 1% with dipivalyl epinephrine (Propine) 0.1% confirm that both have a significant effect in lowering the intraocular pressure in patients with open-angle glaucoma and ocular hypertension, but it is generally insufficient to warrant their use as the first line medical treatment of these two conditions. There was no significant difference between the intraocular lowering effect of the two preparations, and 60% of patients receiving Propine and 66% of those receiving adrenaline noted side effects.  相似文献   
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Testimony provided by Kemp (1991) before the Subcommittee on Employment Opportunities of the U.S. House of Representatives provided occupational therapists with an open invitation to become involved with the implementation of the ADA: [The] EEOC's [Equal Employment Opportunity Commission's] Office of General Counsel anticipates that a significant portion of the ADA cases will require the use of medical, architectural, ergonomics or vocational specialists. These experts will be called on to provide advice and guidance on general and specific ADA issues and to provide specific advice and testimony in certain cases. (Kemp, 1991 [no page no.]) We need to rally to this opportunity. Occupational therapists' knowledge and understanding of the Americans With Disabilities Act of 1990 is an important component to providing comprehensive services to clients. It is crucial that we as occupational therapists become sophisticated regarding the implications of the ADA and advocate for its implementation for our clients.  相似文献   
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