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991.
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BACKGROUND: Image-guided percutaneous drainage has been shown to be a safe and effective alternative to surgery in the management of psoas abscess in adults and adolescents. There is little information on its use in children. OBJECTIVE: To evaluate the safety and efficacy of US-guided percutaneous needle aspiration and catheter drainage of ilio-psoas abscesses. MATERIALS AND METHODS: A retrospective review of 14 children with 16 ilio-psoas abscesses (10 pyogenic and 4 tuberculous) who were treated by US-guided percutaneous needle aspiration (n = 5) or catheter drainage (n = 9) along with appropriate antimicrobial therapy. RESULTS: Percutaneous treatment was successful in 10 of the 14 patients; all showed clinical improvement within 24-48 h of drainage and subsequent imaging demonstrated resolution of the abscess cavities. Surgery was avoided in all of these ten patients except one, who underwent open surgical drainage of ipsilateral hip joint pus. Of the other four patients, two had to undergo surgical drainage of the ilio-psoas abscesses after failure of percutaneous treatment, one improved with antibiotics after needle aspiration failed to yield any pus, and one died of continuing staphylococcal septicaemia within 24 h of the procedure. There were no procedural complications. CONCLUSIONS: Percutaneous drainage represents an effective alternative to surgical drainage as a supplement to medical therapy in the management of children with ilio-psoas abscesses.  相似文献   
994.
PURPOSE: This retrospective study was conducted to review the results of treatment and to identify prognostic factors for local and regional control in a population of 378 patients with nasopharyngeal carcinomas treated in a single institution by radiation therapy alone. METHODS AND MATERIAL: All patients were treated at The University of Texas M. D. Anderson Cancer Center between 1954 and 1992 following a consistent treatment philosophy but with evolving technique. There were 286 males and 92 females with a median age of 52 years (range: 16-86 years). The majority of the patients were Caucasian (282 patients, 75%). Thirty-two patients (8%) had one or more cranial nerve deficits. Three-fourths of the patients presented with AJCC Stage IV disease (T4, N0-3, 118 patients; T1-3, N2-3 164 patients). Histologically, 193 tumors (51%) were squamous cell carcinomas, 154 (41%) lymphoepitheliomas, and 31 (8%) unclassified carcinomas. Average total dose varied with T-stage and ranged from 60.2 to 72.0 Gy. Median follow-up time was 10 years. RESULTS: For the entire population the 5-, 10-, and 20-year actuarial survival rates were 48, 34, and 18%, respectively, with 184 patients (49%) dying of nasopharyngeal cancer. Actuarial control rates at 5, 10, and 20 years were 71, 66, and 66% for the primary site and 84, 83, and 83% for the neck. A total of 100 patients (26%) had local failures and 51 patients (13%) had regional failures with a median time to recurrence of 8.2 months and 13 months, respectively. Advanced T-stage, squamous histology, and presence of cranial nerve deficits were poor prognostic factors for local control in both univariate and multivariate analyses. N-stage and tumor histology were significant factors for neck control. Treatment year, total dose within the ranges used, and duration of treatment did not have any significant effect on local or regional control. The actuarial incidence of Grade 3-5 late complications was 16, 19, and 29% at 5, 10, and 20 years, respectively. Twelve patients (3%) died of treatment-related complications; all but one fatal complication occurred before 1971 and the other in 1976. CONCLUSIONS: This study shows very good long-term local and regional control rates for nasopharyngeal carcinomas after definitive radiotherapy and establishes a benchmark for newer treatment strategies. Improvements in treatment technique over the years have dramatically reduced the frequency of severe late complications. Patients with advanced stage tumors and differentiated squamous histology have a relatively poor prognosis when treated with conventional radiotherapy and are candidates for dose escalation or combined modality studies.  相似文献   
995.
As we demonstrated earlier, platelets adhere to intact endothelium provided they are activated and convectively transported against the endothelial surface. To identify the platelet receptors involved we superfused cultured endothelium with activated platelet rich plasma (PRP) by means of the Stagnation Point Flow Adhesio- Aggregometer while blocking various platelet receptors. Inhibition was performed with the tetrapeptide RGDS, the non-peptide Ro-43-8857, or a monoclonal antibody directed against integrin alphaIIbeta3. Platelet deposition was video-recorded and quantified by image analysis. Infusion of RGDS or Ro-43-8857 into ADP-stimulated PRP completely prevented adhesion as well as subsequent aggregation. Interrupting the inhibitor infusion while ADP stimulation persisted, prompted adhesion and aggregation, demonstrating the reversibility of the inhibition. Platelet adhesion was irreversibly blocked by preincubation of the PRP with the moab against alphaIIbeta3. Its specific binding was confirmed by immunoelectron microscopy. Our results suggest that platelet adhesion to intact endothelium is mediated via platelet integrin alphaIIbeta3.  相似文献   
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Before appropriate therapy can be instituted for a cancer patient, the presence and extent of tumor must be evaluated. Deciding which imaging technique to use depends on tumor location, type, and biologic behavior. Conventional radiography provides important information at a relatively low cost compared with other imaging modalities. Ultrasound is a valuable adjunct to radiography, but does not replace it because both imaging modalities provide unique information. Nuclear medicine procedures contribute additional, unique data by providing physiological information, but specificity is lacking. Both CT and MRI provide images with exquisite anatomic detail, but availability and cost prohibit their general use.  相似文献   
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Male and female subjects (n = 125) were measured on a battery of anthropometric tests every six months for a period of five years. Using maturity status as the temporal component (pubescent assessment stages one through five), proportionality characteristics of subjects were monitored as they matured toward the adult form. Subjects were assigned to one of the Hi, Mid and Lo sub-groups based on their score at PA stage one for each of 15 proportionality characteristics. Subsequently, those in the Mid group were removed from the analysis, while male and female subjects were pooled for the final ANOVA model. The results showed that a number of variables remained stable from PA stages one through five. That is, differences between the Hi and Lo groups were maintained throughout maturation. Predominantly, these included the proportional body segment breadth measures. Proportionality characteristics of the upper limbs appeared to stabilise from mid-adolescence. However, those related to the lower limb were not stable. In other words, a significant difference for the lower limb variables at PA stage one was not maintained through stages four and five. The results raised some doubts as to the suitability of using lower limb proportions as selection criteria in talent identification programs.  相似文献   
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