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排序方式: 共有283条查询结果,搜索用时 15 毫秒
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Long‐term treatment with allergoid immunotherapy with Parietaria. Clinical and immunologic effects in a randomized, controlled trial 总被引:1,自引:0,他引:1
BACKGROUND: Specific immunotherapy (SIT) is a valuable treatment for respiratory allergy, and the use of chemically modified allergens (allergoids) has improved its safety, as testified by several studies. We evaluated the effects of a SIT course with an allergoid extract of Parietaria pollen in a double-blind, placebo-controlled trial. METHODS: The study was double-blind in the first year; then it was prolonged up to 3 years with all patients on active treatment. Clinical effectiveness, safety, skin reactivity, systemic immunologic parameters, and subjective assessment were evaluated. We also had available a self-evaluation recorded in a follow-up visit 4 years after the discontinuation of SIT. RESULTS: A significant reduction of the symptoms plus drug intake scores during the pollen seasons was observed in the patients receiving active SIT. The placebo patients, after switching to active SIT, also showed significant clinical improvement. The clinical efficacy persisted during years 2 and 3 of treatment. After year 1, the actively treated patients reported a significant subjective improvement (frequency of symptoms, P = 0.001; duration of symptoms, P = 0.024; physical performance, P = 0.043) compared with the placebo group. The self-evaluation by visual analog scale showed that all patients maintained a significant clinical improvement up to 4 years after discontinuing SIT (year 1: active=+31.6%, placebo=-15.7%; year 7: active=+35.8%, placebo=+31.3%). The systemic immunologic changes after active SIT paralleled those described elsewhere (IgE decreased from 22 to 9 and from 21 to 8 IU/ml; IgG4 increased from 43 to 87 and from 18 to 60 IU/ml). A significant decrease in skin reactivity to three different allergen concentrations was observed at year 3 compared with pretreatment values (P<0.05). CONCLUSIONS: The investigational SIT with Parietaria appeared to be effective and safe; a 3-year course of treatment achieved a long-lasting efficacy. 相似文献
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LJ Bell L Oliver P Vial TN Eade M Rinks E Hammond GW Morgan M Back KL Wiltshire 《Journal of Medical Imaging and Radiation Oncology》2010,54(1):82-89
The aim of this paper is to detail the experience obtained in implementing an image-guided radiation therapy program at the Northern Sydney Cancer Centre. This required retrofitting a Varian Clinac 21EX with an on-board imager. The commissioning and quality assurance procedures, organisation of a multidisciplinary image guided radiation therapy group, and the development of clinical protocols for orthogonal kV and cone beam computed tomography implementation are described. Reassessment of the image-guided radiation therapy program has continued as new equipment and software versions were made available in the department. 相似文献
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CP Murray PM Wong J Louw GW Waterer 《Journal of Medical Imaging and Radiation Oncology》2009,53(4):339-344
To determine the prevalence of small lung nodules on low‐dose helical computed tomography (CT) in a Western Australian cohort of asymptomatic long‐term cigarette smokers and to compare this with a large, similarly derived cohort of North Americans from the Mayo Clinic Lung Cancer Screening Trial. Forty‐nine asymptomatic long‐term cigarette smokers of minimum age 50 years underwent a low‐dose 64‐slice helical CT of the lungs. Images were viewed on a soft copy reporting station with thin section axial and coronal images, maximum intensity projection images, and advanced image manipulation tools. The prevalence of all nodules was 39%, significantly lower than the Mayo Clinic cohort prevalence of 51% (P < 0.01, Fisher's exact test), despite the use of more advanced imaging technology and image manipulation designed to increase the sensitivity for nodules. The prevalence of small nodules in asymptomatic long‐term cigarette smokers in Western Australia is high, though significantly less than that found in a large study in North America. The authors postulate this is due to the relatively low rates of mycobacterium tuberculosis and soil‐derived fungal pulmonary infections in Western Australia, as well as a lower degree of urban air pollution. 相似文献
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Transrectal endosonography is one of the most sensitive techniques to evaluate prostatic disease and is far more accurate than conventional sonography. A retrospective review of sonographic characteristics of the prostate was made in an attempt to define the ability of the technique to distinguish benign from malignant disease. Analysis included evaluation of the capsule (smoothness, regularity, and/or invasion), abnormal foci (echogenicity, margination, brightness, thickness, and symmetry), and presence of acoustic shadowing and/or enhancement from the abnormal foci. Evaluation of 443 pathologically proved cases (the majority being large lesions) showed that differentiation between benign and large and/or invasive malignant disease may be suggested by results of transrectal endosonography. However, there is still great overlap of the sonographic appearances. 相似文献
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Pond GD; Seeley GW; Ovitt TW; Chernin MM; Yoshino MT; Roehrig H; McIntyre KE 《Radiology》1989,170(2):367-370
This prospective study compared images obtained with a photostimulable imaging plate with matched images obtained with a conventional screen-film combination in 26 patients undergoing intraoperative arteriography. Diagnostic accuracy of the two techniques was assessed objectively, and image quality was assessed subjectively. In 16 patients (62%), the radiation exposure was reduced by 50% for the imaging plate technique by decreasing the mAs level generally used for the screen-film combination. Because of the dynamic range of the imaging plate system, no repeat examinations were necessary, while 12% of the screen-film studies had to be repeated because of over- or under-penetration. Imaging plate studies required 6% more time for processing than screen-film studies. Receiver-operating-characteristic analysis indicated no difference in diagnostic accuracy between the two imaging techniques. Subjective evaluation also revealed no difference in observer preference for imaging plate or screen-film studies. The imaging plate technique is an excellent alternative to screen-film studies in the operating room. 相似文献