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81.
82.
We present a case of melanotic neuroectodermal tumor in the maxilla that followed an aggressively malignant course. In the first biopsy the tumor showed a classical histological picture, while in the last biopsy only malignant undifferentiated cells were evident. The tumor recurred twice after excision, and in spite of radiotherapy and various chemotherapeutic measures the patient died within 16 months of onset. Similar cases reported in the literature are discussed.  相似文献   
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84.
Bioactive glass-ceramics in facial skeleton contouring   总被引:1,自引:0,他引:1  
The removal of certain facial-bone defects is a prerequisite to restoration of function, stability, and appearance. Synthetic bone substitutes are beneficial in cases where other operative techniques would be an unacceptable burden for a patient. Satisfactory results can be achieved in one surgical intervention with low costs and low demand on technical equipment. Osteoconductive, biocompatible, non-resorbable glass-ceramic implants based on oxyfluoroapatite and wollastonite permit osteointegration—a direct physical and chemical bond between live bone tissue and the implant without formation of a fibrous capsule. They display better stress durability in simulated body fluid than hydroxyapatite implants do. This material was used for facial skeletal framework, contour restoration in 44 cases under conditions where other solutions were doubtful. Patients were observed for 24.8 months. Immediate healing occurred without any adverse reaction. The main problem was extrusion, observed in 20.45% cases over a 2–3 month period after the implantation. All cases, with one exception, were solved with a satisfactory final result by reoperation, implant size reduction, and increased soft tissue cover. This approach was found to be a suitable technique, especially for patients exhausted by prior incompetent treatment but still dissatisfied with their appearance. Successful reconstruction with a bone substitute may remarkably increase quality of life for affected persons and, at the same time, reduce surgery-related time and costs.  相似文献   
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The aim of the research was to select some easily available and easily replicable biological markers that could be used as predictors of both acute and long-term therapy. A selection of state markers (structural computer tomography [CT] parameters, psychological parameters, tests concentrating on attention and memory, "soft signs"), trait markers (quantified electroencephalograph [QEEG], cortisolemia, prolactinemia [PRL], and their changes) and clinical symptoms (Positive and Negative Syndrome Scale [PANSS], Clinical Global Impression [CGI]) were determined in 52 hospitalised schizophrenic patients showing either an acute episode or an exacerbation. The evaluation was repeated after one year of outpatient therapy. The parameters studied so far are not sufficiently specific and sensitive; therefore, the prediction cannot be based on a single parameter. In order to overcome this shortcoming, we carried out the analysis by means of multidimensional statistics, applying discriminant analysis. The results of both a broader and a more specific approach are stated in the paper. In all the used examples of discriminant analysis, the optimum discriminator is cortisolemia or its changes after administering dexamethasone and structural CT parameters. The results indicate that combinations of vulnerability markers and state markers (cortisolemia) may be of predictive value and are compatible with the vulnerability-stress ethiopathogenetic model of schizophrenia.  相似文献   
87.
OBJECTIVE: Both donor pulmonary macrophages and recipient circulating leukocytes may be involved in reperfusion injury after lung transplantation. By using the macrophage inhibitor gadolinium chloride and leukocyte filters, we attempted to identify the roles of these two populations of cells in lung transplant reperfusion injury. METHODS: With our isolated, ventilated, blood-perfused rabbit lung model, all groups underwent lung harvest followed by 18-hour cold storage and 2-hour blood reperfusion. Measurements of pulmonary artery pressure, lung compliance, and arterial oxygenation were obtained. Group I (n = 8) served as a control. Group II (n = 8) received gadolinium chloride at 14 mg/kg 24 hours before lung harvest. Group III (n = 8) received leukocyte-depleted blood reperfusion by means of a leukocyte filter. RESULTS: The gadolinium chloride group had significantly improved arterial oxygenation and pulmonary artery pressure measurements compared with control subjects and an improved arterial oxygenation compared with the filter group after 30 minutes of reperfusion. After 120 minutes of reperfusion, however, the filter group had significantly improved arterial oxygenation and pulmonary artery pressure measurements compared with the control group and an improved arterial oxygenation compared with the gadolinium chloride group. CONCLUSIONS: Lung transplant reperfusion injury occurs in two phases. The early phase is mediated by donor pulmonary macrophages and is followed by a late injury induced by recipient circulating leukocytes.  相似文献   
88.
BACKGROUND: We sought to identify the role of retinoic acid (RA) upon lung growth. RA has a role in perinatal lung development, and we hypothesized that exogenous RA would enhance postpneumonectomy compensatory lung growth. METHODS: Utilizing the postpneumonectomy rat model, we studied the impact of RA upon contralateral lung growth. Adult Sprague-Dawley rats were divided into three groups. Group S underwent a sham left thoracotomy, group P underwent left pneumonectomy, and group R underwent left pneumonectomy with administration of exogenous RA (0.5 microg/g/day intraperitoneally). We then quantitated right lung growth after 10 and 21 days. Lung weight and volume were expressed as a ratio to the final body weight (lung weight and volume indices, LWI and LVI). Epidermal growth factor receptor (EGFR) expression was quantitated using Western blot analysis. Cellular proliferation index (CPI) was determined using BrdU immunostaining. RESULTS: LWI, LVI, CPI, and EGFR expression at 21 days were significantly higher in group R versus S and P. At the 10-day interval, both LWI and LVI were significantly higher in group R versus S and P. CONCLUSIONS: RA administration markedly enhances lung growth after pneumonectomy, as evidenced by increases in LWI, LVI, and CPI. Upregulation of EGFR expression was associated with these effects.  相似文献   
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90.
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