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41.
Optimum ratio of distraction in double level tibial lengthening 总被引:2,自引:0,他引:2
Choi IH Sohn CS Chung CY Cho TJ Lee JW Lee DY 《Clinical orthopaedics and related research》1999,(368):240-246
The authors reviewed 43 double level tibial lengthenings by Ilizarov technique in 34 consecutive patients (6-31 years old), and investigated the factors affecting regenerate bone healing to determine the optimum ratio of distraction rate or magnitude of lengthening at the proximal and distal osteotomy sites. Length gain averaged 6.1 cm (range, 2.5-12.3 cm), equivalent to a 28% increase of the segment. The variables investigated included age, gender, concomitant deformity correction, etiology, and the amount of length gain. The healing index averaged 1.8 months per centimeter proximally and 2.8 months per centimeter distally. Age and the amount of length gain affected the healing index at proximal and distal lengthening sites. However, the proximal to distal healing index ratio, which averaged 0.72, was not affected by any parameters investigated. This study suggests that to minimize external fixation treatment time, the distraction rate, or amount of length gain, of the distal osteotomy site should be approximately 3/4 that of the proximal site in the double level tibial lengthening. 相似文献
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PURPOSE: To analyse chromosome aberrations in nuclear-power-plant workers taking account of the mean lifetime of lymphocytes (MLTL). MATERIALS AND METHODS: Analysis of chromosome aberrations was performed on peripheral lymphocytes from 395 nuclear-power-plant workers and 135 controls. An equivalent acute dose (EAD) was calculated utilizing MLTL values of either 4.3 or 10 years. RESULTS: Using an MLTL value of 10 years produced an EAD range of 0.O1 mSv -182mSv(mean 46.6mSv), while using an MLTL, of 4.3 years produced results ranging from 0.01 mSv to 86.2 mSv (mean 23.4 mSv). A significant increase of chromosome-type exchange by the equivalent acute dose was observed using an MLTL of either 10 or 4.3 years when including the control in the analysis, but a significant increase was not seen when only the exposed was considered. A significant increase of chromosome-type deletion by EAD was seen even when only the exposed group was considered. CONCLUSIONS: EAD values based on an MLTL of either 4.3 or 10 years, as well as cumulative dose, showed no significant association with chromosome aberrations, when radiation workers only were analysed. The narrow dose range examined in this study might have contributed to this finding. 相似文献
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Comparing MR imaging and CT in the staging of gastric carcinoma 总被引:49,自引:0,他引:49
Sohn KM Lee JM Lee SY Ahn BY Park SM Kim KM 《AJR. American journal of roentgenology》2000,174(6):1551-1557
OBJECTIVE: The purpose of this study was to assess the usefulness of breath-hold two-dimensional (2D) fast low-angle shot (FLASH) and T2-weighted turbo spin-echo fast MR imaging compared with helical CT in the staging of gastric carcinoma. SUBJECTS AND METHODS: Thirty patients with gastric carcinoma underwent preoperative MR imaging and helical CT. MR imaging at 1.5 T was performed immediately after the intramuscular injection of scopolamine and the oral administration of water or effervescent granules. Breath-hold 2D FLASH T1-weighted images in all three planes, turbo spin-echo T2-weighted axial images, and gadolinium-enhanced fat-suppressed 2D FLASH axial images were included. Helical CT was performed 60 sec after initiation of i.v. contrast medium injection (2.5-3 ml/sec). Two groups of two radiologists each independently analyzed the MR and helical CT findings, and these results were compared with the pathologic findings. RESULTS: For T staging, MR imaging accuracy was higher than that of helical CT (73.3% and 66.7%, respectively); however, the accuracies of the two methods were not significantly different from each other (McNemar test, p > 0.05). Overstaging was noted in 6.7% of cases with MR imaging and 10% with helical CT. Understaging was noted in 20% of cases with MR imaging and 23.3% with helical CT. For N staging, the accuracies of MR imaging and helical CT were 55% and 58.6%, respectively, with no statistical significance (overstaging, 10% and 6.9%; understaging, 34.5% and 34.5%, respectively). CONCLUSION: MR imaging was comparable to helical CT in the T and N staging of gastric cancer. 相似文献
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Elizabeth E. Springston Claudia H. Lau Parav Patel Manoj R. Warrier Min‐Woong Sohn Jacqueline Pongracic Ruchi S. Gupta 《Pediatric allergy and immunology》2012,23(7):642-647
Objective: To evaluate a brief educational tool for pediatricians developed to address known gaps in food allergy knowledge. Study Design: Pre‐ and post‐assessments were administered to a convenience sample of 61 US pediatricians completing the Food Allergy Comprehension Tool between February and March of 2010. McNemar’s and Wilcoxon signed rank tests were used to determine whether clinical knowledge of food allergy and level of comfort in caring for food‐allergic children increased significantly after reviewing the tool. Logistic regression models were used to measure the association of participant characteristics with increased knowledge and comfort. Results: Sixty‐one percent of surveyed physicians answered more knowledge questions correctly after reviewing the tool. Significantly more participants correctly indicated that anaphylaxis poses the greatest threat to teenagers rather than young children, and correctly rejected chronic nasal problems as a symptom of food allergy (p < 0.05). Comfort in caring for food‐allergic children increased significantly on all items post‐intervention (p < 0.05). Odds of increased knowledge and comfort were significantly higher among pediatricians without previous training in food allergy. Conclusion: The Food Allergy Comprehension Tool is a rapid way to address known knowledge gaps among pediatricians and to identify areas in need of further intervention. We recommend integration of the tool with current food allergy guidelines. 相似文献
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Stefan Stefanovic Florian Schuetz Christof Sohn Philipp Beckhove Christoph Domschke 《Cancer metastasis reviews》2014,33(1):309-320
Breast cancer is a systemic disease with a primarily local component. Besides surgical resection and irradiation of the locoregional tumor setting, central therapeutic aim is the elimination of disseminated micrometastatic tumor cells using cytostatic and/or hormonal treatment. Nevertheless, in the course of time a majority of patients suffer from systemic recurrence in the form of distant metastases. Intriguingly, in this connection, intratumoral cytotoxic T lymphocytes might serve as independent predictors of treatment efficacy and clinical outcome. Loss of immune balance (tumor dormancy) during intensive cross talk between T cells and tumor cells in the bone marrow microenvironment is suggested one reason for distant metastatic relapse. In this clinical context, further supportive therapies become increasingly attractive, taking immunological features of breast cancer cells into special account. The present review aims to dissect bone marrow-derived cellular antitumor immune responses and translational immunologic treatment options regarding their actual relevance to patients’ clinical benefit and their future directions in breast cancer management. 相似文献
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