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11.
Early stage nasopharyngeal carcinoma: radiotherapy dose and time factors in tumor control 总被引:1,自引:0,他引:1
Chang JT; See LC; Liao CT; Chen LH; Leung WM; Chen SW; Chen WC 《Japanese journal of clinical oncology》1998,28(3):207-213
OBJECTIVE: To evaluate radiotherapy dose and length of treatment in the
control of early stage nasopharyngeal carcinoma (NPC) treated with a
combination of external radiotherapy and brachytherapy, MATERIALS &
METHODS: We reviewed the records of 133 patients with early stage
nasopharyngeal carcinoma (stage I or II, AJC/UICC staging system) who
received definitive radiotherapy in Chang Gung Memorial Hospital from 1979
to 1991. The median follow-up time was 7.1 years with a minimum of 2 years.
All patients were treated with megavoltage external radiotherapy to the
nasopharynx area (63-72 Gy) followed by high dose rate intracavitary
brachytherapy (5-16.5 Gy in one to three fractions, spaced 1-2 weeks
apart). The median total dose and time of irradiation was 75 Gy (69.8-81.4
Gy) and 11.6 weeks (7.8-20 weeks) respectively. Survival analysis was used
to examine the effect of several variables on prognosis. RESULTS: The
5-year rates were 86.4% for local control, 84.7% for disease free survival,
88.5% for actuarial survival and 84.2% for overall survival. The treatment
group (combination of time and dose of irradiation) was the most important
prognostic factor according to Cox's proportional hazard model. Patients
receiving radiation at a total dose of < or = 75 Gy completed in < 12
weeks showed the best prognosis. CONCLUSION: Treatment time and total
treatment dose are both important factors in treating early stage NPC.
Decreasing the total radiation time to < 12 weeks and not exceeding a
radiation dose of 75 Gy gave the best results.
相似文献
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The pulmonary bioprosthetic heart valve: its unsuitability for use as an aortic valve replacement 总被引:1,自引:0,他引:1
Jennings LM Butterfield M Booth C Watterson KG Fisher J 《The Journal of heart valve disease》2002,11(5):668-78; discussion 679
BACKGROUND AND AIM OF THE STUDY: The porcine pulmonary bioprosthetic heart valve represents an alternative means of aortic valve replacement (AVR), though knowledge of its biomechanical function and characteristics is limited. The valve has potential advantages over the aortic bioprosthesis; notably, it lacks the muscular shelf of the right coronary cusp of the latter bioprosthesis. The study aim was to investigate the suitability of the porcine pulmonary bioprosthetic valve for AVR. METHODS: Porcine pulmonary and aortic roots were zero pressure-fixed with 0.5% buffered glutaraldehyde, characterized, and compared with fresh porcine pulmonary and aortic roots. The in-vitro analysis included assessment of mechanical properties, hydrodynamic function, geometry of the pulmonary root, and durability. RESULTS: The fixed pulmonary roots and fresh aortic roots were similar in certain aspects of mechanical response, notably leaflets in the radial direction and the root wall. The fixed pulmonary root was slightly more compliant than the fixed aortic root, and this led to an improvement in forward flow hydrodynamic function. The reverse flow hydrodynamic function of the pulmonary roots was poor; fresh pulmonary roots exhibited a trivial closed valve regurgitant volume. On fixation, this characteristic was aggravated, leading to a gross closed valve regurgitant volume in 50% of all fixed pulmonary roots. The cause of leakage was identified as a prolapsed anterior leaflet. Durability of the fixed pulmonary root was also inferior to that of the fixed aortic root; three fixed pulmonary roots subjected to accelerated fatigue testing showed signs of leaflet macroscopic damage. CONCLUSION: Overall, the performance of the porcine pulmonary bioprosthesis was far inferior to that of the currently used porcine aortic bioprosthesis. Hence, the porcine pulmonary bioprosthetic valve was deemed unsuitable for AVR. 相似文献
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Effects of repetitive bolus injections of zymosan-activated plasma on lung mechanics and airway responsiveness in awake sheep 总被引:1,自引:0,他引:1
J R Snapper M J Butterfield D B Rayburn P L Lefferts 《The American review of respiratory disease》1991,143(3):578-584
We studied the pulmonary effects of repetitive bolus injections of autologous zymosan-activated plasma (ZAP) in nine chronically instrumented awake sheep. Aerosol histamine responsiveness was determined 1 h before and 4.5 h after the first bolus injection of ZAP. Each sheep received in the pulmonary artery a total of eight 5-ml bolus injections of ZAP separated by 30 min. On a separate day, with the order of experimentation varied to avoid sequential bias, six of the nine sheep also received "control" plasma (plasma prepared in the identical fashion as ZAP but not incubated with zymosan). "Control" plasma caused reproducible transient increases in pulmonary artery pressure, but it did not cause alterations in any of the other measured variables. Repetitive bolus injections of ZAP caused reproducible alterations in lung mechanics, pulmonary hemodynamics, lung fluid and solute exchange, oxygenation, and peripheral leukocyte counts. The increases in thromboxane-B2 concentrations in lung lymph and plasma were greatest after the first bolus injection of ZAP, with the magnitude of these changes diminishing on succeeding injections of ZAP. Aerosol histamine responsiveness did not increase after the eight bolus injections of ZAP. 相似文献
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P Valent D Bevec D Maurer J Besemer F Di Padova J H Butterfield W Speiser O Majdic K Lechner P Bettelheim 《Proceedings of the National Academy of Sciences of the United States of America》1991,88(8):3339-3342
Cell recognition molecules play a crucial role in the regulation of immune cells. We recently found that mast cells (MCs) express leukocyte recognition molecules, including ICAM-1 antigen, a natural ligand of LFA-1. We here report that interleukin 4 (IL-4), a pleiotropic cytokine and mast cell differentiation factor, selectively promotes expression of surface ICAM-1 antigen and ICAM-1 mRNA in human MCs. IL-4 also up-regulates ICAM-1 antigen in cells of monocyte/macrophage lineage but has no effect on ICAM-1 antigen expressed on basophils, fibroblasts, or lymphocytes. The increase in expression of mast cell/macrophage ICAM-1 antigen induced by IL-4 may contribute to the accumulation of leukocytes and facilitate cell-contact-dependent regulation of immune cells in inflamed tissues. 相似文献
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