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101.
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   
102.
Lipopolysaccharide (LPS) preconditioning provides neuroprotection against subsequent cerebral ischemic injury. Tumor necrosis factor-alpha (TNFalpha) is protective in LPS-induced preconditioning yet exacerbates neuronal injury in ischemia. Here, we define dual roles of TNFalpha in LPS-induced ischemic tolerance in a murine model of stroke and in primary neuronal cultures in vitro, and show that the cytotoxic effects of TNFalpha are attenuated by LPS preconditioning. We show that LPS preconditioning significantly increases circulating levels of TNFalpha before middle cerebral artery occlusion in mice and show that TNFalpha is required to establish subsequent neuroprotection against ischemia, as mice lacking TNFalpha are not protected from ischemic injury by LPS preconditioning. After stroke, LPS preconditioned mice have a significant reduction in the levels of TNFalpha (approximately threefold) and the proximal TNFalpha signaling molecules, neuronal TNF-receptor 1 (TNFR1), and TNFR-associated death domain (TRADD). Soluble TNFR1 (s-TNFR1) levels were significantly increased after stroke in LPS-preconditioned mice (approximately 2.5-fold), which may neutralize the effect of TNFalpha and reduce TNFalpha-mediated injury in ischemia. Importantly, LPS-preconditioned mice show marked resistance to brain injury caused by intracerebral administration of exogenous TNFalpha after stroke. We establish an in vitro model of LPS preconditioning in primary cortical neuronal cultures and show that LPS preconditioning causes significant protection against injurious TNFalpha in the setting of ischemia. Our studies suggest that TNFalpha is a twin-edged sword in the setting of stroke: TNFalpha upregulation is needed to establish LPS-induced tolerance before ischemia, whereas suppression of TNFalpha signaling during ischemia confers neuroprotection after LPS preconditioning.  相似文献   
103.
The use of deep brain stimulation (DBS) to treat movement disorders such as Parkinson's disease, essential tremor, and dystonia is increasing. Although some published literature describes the methods for DBS programming, the time and nursing requirements to run a DBS surgical program have not been examined previously. For this study, we prospectively recorded the time required for both assessments and programming of the DBS from the preoperative period to 1 year after surgery in a variety of patients. Results showed that the mean total time spent programming the stimulator and assessing these patients ranged from 18.0-36.2 hours per patient. It took twice as long to program the stimulator in patients with Parkinson's disease as it did in patients with essential tremor or dystonia. When setting up a program for movement disorders surgery, nursing time spent on patient assessment and programming should be considered in the workload.  相似文献   
104.
BACKGROUND: The life expectancy of individuals with CF has increased to 33 years. Thus, issues such as quality of life and psychological well-being, previously thought to be of lesser importance than physical well-being, are now recognised as significant factors. This study examined the interrelationships between quality of life, family functioning, individual psychopathology and optimism of adolescents with CF. METHODS: Adolescents attending the CF clinic completed a number of questionnaires. Quality of Life was measured using the Cystic Fibrosis Questionnaire, family functioning by the Family Environment Scale (3rd edition), general psychopathology with the Symptom Checklist-90-Revised and optimism for the future by the Hunter Opinions and Personal Expectations Scale. Disease severity was assessed using the Shwachman score and spirometry at the time of questionnaire completion. RESULTS: The level of psychopathology (12.5% of those 13 years and over) in the group was lower than that reported for young people in Australia (15-20%). The results indicated that young people with a delayed diagnosis and those who are alienated from their families may be in need of additional psychosocial support. The group was hopeful and positive about their future and these attributes were independent of clinical measures of disease severity. In general, these young people scored relatively highly on the quality of life scale. For example the mean standardised score for physical functioning was 70 points, for respiratory symptoms was 63 points and for emotional state was 78 points. Increased levels of psychopathology and lack of hope for the future were however associated with lower ratings on a number of quality of life measures. Family cohesiveness, expressiveness and organization were associated with better psychological functioning in the young people. CONCLUSIONS: Adolescents with CF appear to be a psychologically well functioning and well-adjusted group. These findings support the importance of a more sophisticated model of well-being for adolescents with CF, which explores the young person's views on their quality of life and wider support frameworks rather than relying solely on measures of physical health to gauge well-being.  相似文献   
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In recent work, we have demonstrated that testosterone propionate accelerates recovery from facial nerve injury in the adult male hamster. Central synaptic stripping following peripheral motor neuron damage is a well-established component of the injury response. Gonadal steroids regulate synaptogenesis in the normal nervous system. In this study, we tested the hypothesis that testosterone propionate administration at the time of facial nerve transection alters the synaptic connectivity of injured facial motoneurons. Adult hamsters were subjected to right facial nerve transection at the level of the stylomastoid foramen. Half the animals received subcutaneous implants of testosterone propionate; the other half were sham implanted. At 5 days postoperative, the animals were killed by intracardiac perfusion-fixation, and the control and axotomized facial nuclear groups from the brainstems of nonhormone- and testosterone propionate-treated animals processed for routine transmission electron microscopy. Quantiative analysis of the synaptic ratio (percent somal membrane covered by synaptic profiles) and the average length of axosomatic synapses was accomplished. The results indicate that axotomy alone resulted in an 81% reduction in the synaptic ratio and a 26% decrease in the average synaptic length of axosomatic synapses. Exposure to testosterone propionate from the time of facial nerve transection resulted in only a 48% reduction in the synaptic ratio and a 16% decrease in the average synaptic length of axosomatic synapses following injury. Thus, testosterone propionate significantly attenuated the amount of synaptic stripping that occurred at 5 days postoperative and the decrease in average length of the remaining synapses as well. It is concluded that gonadal steroids modulate central synaptic plasticity following peripheral nerve injury. The results are discussed in light of our recent findings of steroidal effects on the central astrocyctic response to facial nerve injury as well.  相似文献   
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One goal of supportive housing is to enlarge and improve the functioning of the social support networks of residents. The networks of a convenience sample of 42 residents were assessed using scales developed by Barrera. The size of the networks (11.5) was no larger than that reported for similar clients living in other types of community settings but the composition differed. Staff and co-residents appear to partially replace rather than add to family and friends. This is of concern because friends are uniquely important determinants of satisfaction. An association between perceived need for support and network size was also found. These findings suggest some positive influences but also raise questions about unintended negative consequences of living in artificially constructed social environments.When this project was undertaken, Dr. Goering, Janet Durbin, Bill Lancee and Taras Babiak were all members of the Social and Community Psychiatry Section, Clarke Institute. Robert Foster was Executive Director of Regeneration House, Inc., where Susan Boyles is Assistant Executive Director.  相似文献   
110.
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