Sökresultat

Filtyp

Din sökning på "*" gav 530906 sökträffar

Specialist Ambulance Nurses’ Perceptions of Nursing: A Phenomenographic Study

Although nursing is the main area of interest in the curriculum of the specialist ambulance nursing program in the advanced level of education, there has been reported a lack of knowledge about nursing in within the ambulance service. The aim was to explore specialist ambulance nurses’ perceptions of nursing, which were explored by employing a phenomenographic approach. The study comprises individ

Tensor-valued diffusion MRI differentiates cortex and white matter in malformations of cortical development associated with epilepsy

Objective: Delineation of malformations of cortical development (MCD) is central in presurgical evaluation of drug-resistant epilepsy. Delineation using magnetic resonance imaging (MRI) can be ambiguous, however, because the conventional T1- and T2-weighted contrasts depend strongly on myelin for differentiation of cortical tissue and white matter. Variations in myelin content within both cortex a

Anthropogenic transformation of Yangtze Plain freshwater lakes: patterns, drivers and impacts

Over the past half century, the Yangtze Plain of China has experienced rapid economic development. Lake reclamation (i.e., conversion of natural lake/wetland areas to agricultural/urban land or aquaculture, thereby reducing the area of natural waters) in particular has greatly contributed to meeting the increasing demands for food and urban development. However, until now, a comprehensive quantifi

Sintering of cBN Based Materials with a TaC Binder for Cutting Tool Application

Abstract: Ceramic matrix composites based on cubic boron nitride with a TaC binder phase are sintered under conditions of high pressure and high temperature. The sintering is carried out in a high-pressure apparatus of the toroid type in the temperature range of 1450–2450°C. It is shown that a chemical reaction between components of the mixture with the formation of TaB2 takes place at a sintering

Premature Termination of a Randomized Controlled Trial on Image-Guided Stereotactic Body Radiotherapy of Metastatic Spinal Cord Compression

Lessons Learned: It is possible to plan and treat some patients with stereotactic body radiotherapy (SBRT) in a timely fashion in an acute setting. Advanced and, in some indications, already implemented technologies such as SBRT are difficult to test in a randomized trial. Background: Stereotactic body radiotherapy (SBRT) in metastatic spinal cord compression (MSCC) could be an alternative to deco

Cerebral infarction after fractionated stereotactic radiation therapy of benign anterior skull base tumors

Background: The purpose of this study was to examine the occurrence of cerebral infarction (ischemic stroke), in a large combined cohort of patients with anterior skull base meningiomas, pituitary adenomas and craniopharyngiomas, after fractionated stereotactic radiation therapy (FSRT). Material and Methods: All patients, 18 years and older, with anterior skull base meningiomas, pituitary adenomas

A modality-adaptive method for segmenting brain tumors and organs-at-risk in radiation therapy planning

In this paper we present a method for simultaneously segmenting brain tumors and an extensive set of organs-at-risk for radiation therapy planning of glioblastomas. The method combines a contrast-adaptive generative model for whole-brain segmentation with a new spatial regularization model of tumor shape using convolutional restricted Boltzmann machines. We demonstrate experimentally that the meth

Diabetes increases the risk of serious adverse events after re-irradiation of the spine

Introduction: In this study we investigate the risk of radiation-induced serious adverse event of the spine in a large cohort of consecutive retreated patients with palliative radiotherapy (RT) for metastatic cancer in the spine. Methods and materials: From 2010 to 2014, 2387 patients received spinal irradiation with a palliative intent for metastatic spinal cord compression at our institution. T

Influence of volumetric modulated arc therapy and FET-PET scanning on treatment outcomes for glioblastoma patients

Background: We sought to assess the influence of the clinical introduction of new radiotherapy technologies on glioblastoma patients’ outcomes. Methods: Newly diagnosed glioblastoma patients treated with 60 Gy and temozolomide (2005–2014) were analyzed. The patients’ GTV and CTV were defined based on MR (n = 521) or FET-PET/MR (n = 190), and were treated using conformal radiotherapy (CRT, n = 159)

Feasibility of multi-parametric PET and MRI for prediction of tumour recurrence in patients with glioblastoma

Background: Recurrence in glioblastoma patients often occur close to the original tumour and indicates that the current treatment is inadequate for local tumour control. In this study, we explored the feasibility of using multi-modality imaging at the time of radiotherapy planning. Specifically, we aimed to identify parameters from pre-treatment PET and MRI with potential to predict tumour recurr

Image-guided radiotherapy reduces the risk of under-dosing high-risk prostate cancer extra-capsular disease and improves biochemical control

Background: To determine if reduced dose delivery uncertainty is associated with daily image-guidance (IG) and Prostate Specific Antigen Relapse Free Survival (PRFS) in intensity-modulated radiotherapy (IMRT) of high-risk prostate cancer (PCa). Methods: Planning data for consecutive PCa patients treated with IMRT (n = 67) and IG-IMRT (n = 35) was retrieved. Using computer simulations of setup erro

Toxicity and efficacy of re-irradiation of high-grade glioma in a phase I dose- and volume escalation trial

Introduction The purpose of this study was to evaluate the safety and efficacy of PET and MRI guided re-irradiation of recurrent high-grade glioma (HGG) and to assess the impact of radiotherapy dose, fractionation and irradiated volume. Material and methods Patients with localized, recurrent HGG (grades III-IV) and no other treatment options were eligible for a prospective phase I trial. Gross tum

Dose painting based on tumor uptake of Cu-ATSM and FDG : a comparative study

BACKGROUND: Hypoxia and increased glycolytic activity of tumors are associated with poor prognosis. The purpose of this study was to investigate differences in radiotherapy (RT) dose painting based on the uptake of 2-deoxy-2-[(18) F]-fluorodeoxyglucose (FDG) and the proposed hypoxia tracer, copper(II)diacetyl-bis(N(4))-methylsemithiocarbazone (Cu-ATSM) using spontaneous clinical canine tumor model

Prospective assessment of urinary, gastrointestinal and sexual symptoms before, during and after image-guided volumetric modulated arc therapy for prostate cancer

Objective. The aim of this study was to prospectively assess the development of 24 urinary, gastrointestinal and sexual symptoms in patients with prostate cancer (PCa) during and after image-guided volumetric modulated arc therapy (IG-VMAT). Material and methods. A total of 87 patients with PCa participated in this study. The patients were asked to complete a modified version of the Prostate Cance

Motion management during IMAT treatment of mobile lung tumors - A comparison of MLC tracking and gated delivery

Results: The average gamma index failure rate (2% and 2 mm criteria) was < 0.01% with amplitude gating for all patients, and < 0.1% with phase gating and < 3.7% with MLC tracking for three of the four patients. One of the patients had an average failure rate of 15.1% with phase gating and 18.3% with MLC tracking.With no motion compensation, the average gamma index failure rate ranged from 7.1% to