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IntroductionAdaptive techniques to deliver radiotherapy to the bladder may ensure treatment accuracy whilst sparing organs at risk. This study assesses the frequency of when an alternative plan to the current standard may be beneficial and establish the treatment resource implications of adaptive techniques. Assess the variation in accuracy of skeletal surrogate compared to the target. Additionally describes a training package for therapeutic radiographers evaluating CBCT datasets for adaptive techniques.MethodsA library of three plans was created for each patient, small, standard and large. Weekly CBCT and planar imaging data were acquired from 10 bladder cancer patients receiving radical radiotherapy. Bladder volumes from weekly CBCT were compared to the planning scan. Image registration was performed using bone and soft tissue structures on the CBCT images. A database of images was created to develop competency assessment and a training package.ResultsMatching to a skeletal surrogate may under estimate movement of the target. Bladder volume can vary significantly during the course of treatment, even in the presence of bladder preparation protocols. The additional time required to implement this technique is 4 min per fraction compared to standard treatment with planar imaging.ConclusionsThis feasibility study is a useful process to facilitate the implementation of adaptive techniques. However a limitation of this study is the low number of CBCT datasets evaluated. The advent of IGRT and adaptive techniques gives increased confidence to reduce margins, consequently facilitating hypo-fractionation, and may provide a gain in linear accelerator efficiency and reduce the number of hospital visits for the patient. CBCT paired with a development programme for therapeutic radiographers is an effective and efficient means of implementing adaptive radiotherapy. 相似文献
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Tabreskhan Pathan Sachin Ingale Ashish Sharma Rhea Mohan C. S. Ramaa 《Medicinal chemistry research》2012,21(5):584-589
A series of difluorinated propanediones were synthesized and evaluated for in vitro cytotoxic activity by Sulforhodamine B
(SRB) assay against a panel of four human cancer cell lines. Though the compounds showed varying degrees of cytotoxicity in
the tested cell lines, most marked effect was observed in breast cancer cell line (MCF7), wherein nine of the ten synthesized
chalcones showed good antiproliferative activity. 相似文献
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Rahul Jain C. Daniel Mullins Helen Lee Winston Wong 《Research in social & administrative pharmacy》2012,8(1):47-59
BackgroundMeta-analyses of oral hypoglycemic agents (OHAs) revealed that rosiglitazone increased the risk of myocardial infarction (MI) and heart failure (HF) and that pioglitazone increased the risk of HF and decreased the risk of MI.ObjectiveTo characterize the change in the pattern of use of OHAs immediately after the publication of these meta-analyses on May 21, 2007.MethodsPharmacy and medical claims data for a managed care organization were analyzed for patients continuously enrolled from January 1, 2005, to November 30, 2007, with at least 1 pharmacy claim for OHA in the 13-month period between November 1, 2006, and November 30, 2007. A 5-month pre-publication period (November 1, 2006, through March 31, 2007) was compared with a 5-month post-publication period (July 1, 2007, through November 30, 2007) using a differences-in-differences multinomial logistic regression. This regression explored discontinuation; continuation with monotherapy or adding another drug; and switching to a drug different from the index monotherapy drug after adjusting for gender, age, type of insurance, past 1-year history of MI or HF, and risk factors for MI and HF in the past 1 year.ResultsThe relative rate of switching to nonindex drug in the postpublication relative to prepublication was 2.64 (P = .046) for monotherapy rosiglitazone users and 0.72 (P = .583) for monotherapy pioglitazone users. The differences-in-differences estimate of the rate of switching to nonindex drugs for monotherapy rosiglitazone users was 3.64 (P = .090) times higher relative to the estimate for monotherapy pioglitazone users.ConclusionThe pattern of use differed fundamentally between monotherapy rosiglitazone users and users of all other monotherapy OHAs in the postperiod. Not only were monotherapy rosiglitazone patients switching to non-rosiglitazone drugs at a higher rate, but the rate also was more than 3 times higher than similar switches among monotherapy pioglitazone users in the postperiod relative to the preperiod. This shows that the market response as observed by patient/prescriber decisions to the adverse news was interpreted narrowly to monotherapy rosiglitazone, and there is little or no spillover to the other drugs. Therefore, this study found that there was a differential effect of meta-analyses on the use of the 2 drugs. 相似文献
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Vikas Maurya Uday Aditya Gupta Ravindra K. Dewan Sudhir Jain Ashok Shah 《Archivos de bronconeumologia》2013,49(1):31-34
Spontaneous, complete resolution of inflammatory pseudotumour (IPT) of lungs is exceptionally rare. A 44-year-old male was referred for evaluation for «non resolving pneumonitis». He had cough and minimal expectoration for 5 months, chest pain, haemoptysis and fever for a fortnight. Computed tomography of thorax (CT-thorax) confirmed the presence of a homogenous mass with irregular borders in right middle lobe with areas of breakdown and air bronchogram. Transbronchial lung biopsy was suggestive of «plasma cell granuloma». Thoracotomy disclosed a hard mass in right middle lobe adherent to lower lobe, chest wall and mediastinum which could not be removed. A wedge biopsy confirmed IPT. Chest radiograph after 4 weeks revealed significant resolution. CT-thorax a year later showed fibrotic scar. Till date, there are only five reports documenting 6 patients with spontaneous resolution of IPT of lungs and in 4 this occurred within 3 months of an invasive diagnostic intervention. 相似文献