keyword
MENU ▼
Read by QxMD icon Read
search

validation

keyword
https://www.readbyqxmd.com/read/28102972/evaluating-the-clinical-copd-questionnaire-a-systematic-review
#1
REVIEW
Zijing Zhou, Aiyuan Zhou, Yiyang Zhao, Ping Chen
The Clinical COPD Questionnaire (CCQ) is recommended by the Global Initiative for Chronic Obstructive Lung Disease (GOLD) to evaluate health status in patients with COPD. The objective of this work was to systemically assess the reliability, validity, responsiveness and minimum clinically important difference (MCID) of the CCQ. A structured search was conducted in three databases to identify articles that evaluated the psychometric properties of the CCQ in individuals with COPD. Two investigators screened the title, abstract and full text of the articles to determine study eligibility and performed the data extraction...
February 2017: Respirology: Official Journal of the Asian Pacific Society of Respirology
https://www.readbyqxmd.com/read/28102971/how-is-physical-activity-measured-in-lung-cancer-a-systematic-review-of-outcome-measures-and-their-psychometric-properties
#2
REVIEW
Lara Edbrooke, Linda Denehy, Selina M Parry, Ronan Astin, Sandy Jack, Catherine L Granger
Physical activity (PA) levels are low in patients with lung cancer. Emerging evidence supports the use of interventions to increase PA in this population. We aimed to (1) identify and synthesize outcome measures which assess PA levels in patients with lung cancer and (2) to evaluate, synthesize and compare the psychometric properties of these measures. A systematic review of articles from searches was conducted of five electronic databases and personal records. Eligible studies were those which assessed PA using either performance-based or patient-reported measures...
February 2017: Respirology: Official Journal of the Asian Pacific Society of Respirology
https://www.readbyqxmd.com/read/28102957/rf-safety-assessment-of-a-bilateral-four-channel-transmit-receive-7-tesla-breast-coil-sar-versus-tissue-temperature-limits
#3
Thomas M Fiedler, Mark E Ladd, Andreas K Bitz
PURPOSE: The purpose of this work was to perform an RF safety evaluation for a bilateral four-channel transmit/receive breast coil and to determine the maximum permissible input power for which RF exposure of the subject stays within recommended limits. The safety evaluation was done based on SAR as well as on temperature simulations. In comparison to SAR, temperature is more directly correlated with tissue damage, which allows a more precise safety assessment. The temperature simulations were performed by applying three different blood perfusion models as well as two different ambient temperatures...
January 2017: Medical Physics
https://www.readbyqxmd.com/read/28102955/compound-speckle-model-detects-anti-angiogenic-tumor-response-in-preclinical-nonlinear-contrast-enhanced-ultrasonography
#4
Matthew R Lowerison, Justin J Tse, M Nicole Hague, Ann F Chambers, David W Holdsworth, James C Lacefield
PURPOSE: This paper proposes a method for analyzing the first-order speckle statistics of nonlinear contrast-enhanced ultrasound images from tumors. METHODS: Contrast signal intensity is modeled as a compound distribution of exponential probability density functions with a gamma weighting function. The gamma probability weighting function serves as an approximation for log-normally distributed flow velocities in a vascular network. The model was applied to sub-harmonic bolus-injection images acquired from a mouse breast cancer xenograft model treated with murine version bevacizumab...
January 2017: Medical Physics
https://www.readbyqxmd.com/read/28102954/dosimetric-impact-of-lipiodol-in-stereotactic-body-radiation-therapy-on-liver-after-trans-arterial-chemoembolization
#5
Daisuke Kawahara, Shuichi Ozawa, Akito Saito, Teiji Nishio, Tomoki Kimura, Tatsuhiko Suzuki, Kazunari Hioki, Takeo Nakashima, Yoshimi Ohno, Yuji Murakami, Yasushi Nagata
PURPOSE: Stereotactic body radiation therapy (SBRT) combining trans-arterial chemoembolization (TACE) with Lipiodol is expected to improve local control. This study is aimed to estimate the dose enhancement in Lipiodol's proximity and to evaluate the dose calculation accuracy of the Acuros XB (AXB) algorithm and anisotropic analytical algorithm (AAA) in the Eclipse treatment planning system (TPS) (ver. 11, Varian Medical Systems, Palo Alto, USA), compared with that of the Monte Carlo (MC) calculation (using BEAMnrc/DOSXYZnrc code) for a virtual phantom and a treatment plan for liver SBRT after TACE...
January 2017: Medical Physics
https://www.readbyqxmd.com/read/28102953/air-kerma-strength-determination-of-an-hdr-192-ir-source-including-a-geometric-sensitivity-study-of-the-seven-distance-method
#6
Blake R Smith, John A Micka, Manik Aima, Larry A DeWerd, Wesley S Culberson
PURPOSE: To perform an in-air air-kerma strength (SK) calibration of the Bebig model Ir2.A85-2 192Ir high-dose rate (HDR) brachytherapy source manufactured by Mallinckrodt Medical (Westerduinweg, Germany) with the NIST-traceable seven-distance technique established by the University of Wisconsin. A comparison was made between the reference air-kerma rate (RAKR) reported on a certificate from the Physikalisch-Technische Bundesanstalt (Berlin, Germany) (PTB) primary laboratory and the SK determined at the University of Wisconsin Madison Radiation Research Center (UWMRRC)...
January 2017: Medical Physics
https://www.readbyqxmd.com/read/28102951/direct-and-fast-measurement-of-ct-beam-filter-profiles-with-simultaneous-geometrical-calibration
#7
Kai Yang, Xinhua Li, X George Xu, Bob Liu
PURPOSE: To accurately measure the beam filter profiles from a variety of CT scanner models and to provide reference data for Monte Carlo simulations of CT scanners. METHODS: This study proposed a new method to measure CT beam filter profiles using a linear-array x-ray detector (X-Scan 0.8f3-512; Detection Technology Inc., Espoo, Finland) under gantry rotation mode. A robust geometrical calibration approach was developed to determine key geometrical parameters by considering the x-ray focal spot location relative to the linear-array detector and the gantry's angular increment at each acquisition point...
January 2017: Medical Physics
https://www.readbyqxmd.com/read/28102948/use-of-parallel-plate-ionization-chambers-in-reference-dosimetry-of-novac-and-liac-%C3%A2-mobile-electron-linear-accelerators-for-intraoperative-radiotherapy-a-multi-center-survey
#8
Paolo Scalchi, Alessia Ciccotelli, Giuseppe Felici, Assunta Petrucci, Raffaella Massafra, Valeria Piazzi, Paola D'Avenia, Francesca Cavagnetto, Federica Cattani, Raffaella Romagnoli, Antonella Soriani
PURPOSE: LIAC(®) and NOVAC are two mobile linear accelerators dedicated to intraoperative radiation therapy (IORT), generating electron beams in the energy range of 3-12 MeV. Due to high dose-per-pulse (up to 70 mGy per pulse), in 2003 the Italian National Institute of Health (ISS) stated that "for the measure of dose to water in reference conditions, ionization chambers cannot be employed and no published dosimetry protocol can be used". As a consequence, ferrous sulphate (or, alternatively alanine) dosimetry was recommended...
January 2017: Medical Physics
https://www.readbyqxmd.com/read/28102946/a-portal-dosimetry-dose-prediction-method-based-on-collapsed-cone-algorithm-using-the-clinical-beam-model
#9
J Martínez Ortega, N Gómez González, P Castro Tejero, M Pinto Monedero, N B Tolani, L Núñez Martín, R Sánchez Montero
PURPOSE: Amorphous silicon electronical portal imaging devices (EPIDs) are widely used for dosimetric measurements in Radiation Therapy. The purpose of this work was to determine if a portal dose prediction method can be utilized for dose map calculations based on the linear accelerator model within a commercial treatment planning system (Pinnacle(3) v8.0 m). METHODS: The method was developed for a 6 MV photon beam on the Varian Clinac 21-EX, at a nominal dose rate of 400 MU/min...
January 2017: Medical Physics
https://www.readbyqxmd.com/read/28102944/a-simple-and-robust-trajectory-based-stereotactic-radiosurgery-treatment
#10
Byron Wilson, Karl Otto, Ermias Gete
INTRODUCTION: We present a Trajectory-based Volumetric Modulated Arc Therapy (TVMAT) technique for Stereotactic Radiosurgery (SRS) that takes advantage of a modern linacs ability to modulate dose rate and move the couch dynamically. In addition, we investigate the quality of the developed TVMAT method and the dosimetric accuracy of the technique. METHODS: The main feature of the TVMAT technique is a standard beam trajectory formed by dynamic motion of the treatment couch and the linac gantry...
January 2017: Medical Physics
https://www.readbyqxmd.com/read/28102943/comparison-of-five-cluster-validity-indices-performance-in-brain-18-f-fet-pet-image-segmentation-using-k-means
#11
Bedor Abualhaj, Guoyang Weng, Melissa Ong, Ali Asgar Attarwala, Flavia Molina, Karen Büsing, Gerhard Glatting
PURPOSE: Dynamic [(18) F]fluoro-ethyl-L-tyrosine positron emission tomography ([(18) F]FET-PET) is used to identify tumor lesions for radiotherapy treatment planning, to differentiate glioma recurrence from radiation necrosis and to classify gliomas grading. To segment different regions in the brain k-means cluster analysis can be used. The main disadvantage of k-means is that the number of clusters must be pre-defined. In this study, we therefore compared different cluster validity indices for automated and reproducible determination of the optimal number of clusters based on the dynamic PET data...
January 2017: Medical Physics
https://www.readbyqxmd.com/read/28102942/a-platform-independent-method-to-reduce-ct-truncation-artifacts-using-discriminative-dictionary-representations
#12
Yang Chen, Adam Budde, Ke Li, Yinsheng Li, Jiang Hsieh, Guang-Hong Chen
PURPOSE: When the scan field of view (SFOV) of a CT system is not large enough to enclose the entire cross-section of the patient, or the patient needs to be positioned partially outside the SFOV for certain clinical applications, truncation artifacts often appear in the reconstructed CT images. Many truncation artifact correction methods perform extrapolations of the truncated projection data based on certain a priori assumptions. The purpose of this work was to develop a novel CT truncation artifact reduction method that directly operates on DICOM images...
January 2017: Medical Physics
https://www.readbyqxmd.com/read/28102936/unbiased-and-quantitative-proteomics-reveals-highly-increased-angiogenesis-induction-by-the-secretome-of-mesenchymal-stromal-cells-isolated-from-fetal-rather-than-adult-skin
#13
Massimiliano Gaetani, Cinzia Maria Chinnici, Anna Paola Carreca, Claudia Di Pasquale, Giandomenico Amico, Pier Giulio Conaldi
Scarless wound healing and functional regeneration are typical processes of the fetus, gradually lost during post-natal life, and maximally attributed to fetal skin tissue and induced by fetal skin fibroblasts. The latter have been successfully applied to post-natal wounds, with clear advantages compared with autologous dermis grafts or adult fibroblast applications. Our goal was to functionally identify and uncover key factors and mechanisms through the analysis of secretomes, the principal players in all cell therapies based on mesenchymal stromal cells (MSCs)...
January 19, 2017: Journal of Tissue Engineering and Regenerative Medicine
https://www.readbyqxmd.com/read/28102926/sodiation-based-in-source-collision-for-profiling-of-pyranocoumarins-in-radix-peucedani-qianhu-utility-of-sodium-adducts-stability-with-in-source-collision
#14
Wei Yang, Yingfei Li, Chen Kang, Haiyu Zhao, Li Xiang, Chuan Li, Qiao Wang
Full scan mode of liquid chromatography-mass spectrometry equipped with an electrospray ionization source offers a chance on global detection of complicated components; however, the scan mode carries significant challenges in rapidly capturing information of analysts. Sodiation-based in-source collision was proposed here, as a technique for rapid detecting untargeted analytes in full scan analysis, which was based on the stability of sodium adducts and the nonselectivity of in-source collision. Then the technique was applied to profile of angular-type pyranocoumarins (APs) in Radix Peucedani, with full scan analysis performed at two specific in-source collision energy: a high energy 50 V that is tolerated by the sodium adducts of APs, and a low energy 10 V, at which abundant adducts were offered...
January 19, 2017: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/28102918/medication-administration-errors-and-related-deviations-from-safe-practice-an-observational-study
#15
Alwiena J Blignaut, Siedine K Coetzee, Hester C Klopper, Suria M Ellis
AIMS AND OBJECTIVES: To determine the incidence of medication administration errors, medication administration related deviations from safe practice as well as factors associated with these errors in medical and surgical units of public hospitals in the Gauteng Province of South Africa. BACKGROUND: Several studies have been published on the incidence of medication administration errors, but only a few have studied the incidence of medication administration related deviations from safe practice...
January 19, 2017: Journal of Clinical Nursing
https://www.readbyqxmd.com/read/28102882/factors-associated-with-significant-mri-findings-in-medical-walk-in-patients-with-acute-headache
#16
Joris Budweg, Till Sprenger, Anthony De Vere-Tyndall, Anne Hagenkord, Christoph Stippich, Christoph T Berger
QUESTION: Acute headache is a main reason for emergency consultations and can be a symptom of dangerous neurological conditions. We hypothesised that in medical walk-in headache patients with low suspicion of intracranial bleeding significant findings in brain magnetic resonance imaging (MRI) are associated with clinical features. METHODS: Retrospective chart review on medical outpatient referrals for brain MRI (2010-2014) with the chief complaint "acute headache" (duration <4 weeks)...
January 19, 2017: Swiss Medical Weekly
https://www.readbyqxmd.com/read/28102879/the-conservative-and-pharmacological-management-of-chronic-subdural-haematoma
#17
Jehuda Soleman, Fabio Noccera, Luigi Mariani
Chronic subdural haematoma (cSDH), one of the most common neurosurgical entities, occurs typically in elderly patients. The incidence is expected to double by the year 2030, owing to the continuous aging of the population. Surgery is usually the treatment of choice, but conservative treatment may be a good alternative in some situations. We provide a systematic review of studies analysing the conservative treatment options and the natural history of cSDH. Of 231 articles screened, 35 were included in this systematic review...
January 19, 2017: Swiss Medical Weekly
https://www.readbyqxmd.com/read/28102877/feasibility-acceptability-and-construct-validity-of-eq-5d-in-systemic-sclerosis
#18
Roberta Gualtierotti, Francesca Ingegnoli, Luciana Scalone, Paolo Cortesi, Eleonora Bruschi, Maria Gerosa, Pier Luigi Meroni
BACKGROUND: Systemic sclerosis is a chronic disabling disease that is often associated with severe physical and psychological impairment. Nonetheless, health-related quality of life (HRQoL) in patients with systemic sclerosis is often left behind in clinical practice and research. One of the reasons for this lack of evaluation is the current use of tools, such as the short form-36 (SF-36) questionnaire, that are complete but complicated to use in everyday routine. Other self-reported outcome measures such as the health assessment questionnaire (HAQ) are simple, but specifically designed for physical disability...
January 19, 2017: Swiss Medical Weekly
https://www.readbyqxmd.com/read/28102869/design-considerations-to-minimize-the-impact-of-drug-absorption-in-polymer-based-organ-on-a-chip-platforms
#19
V S Shirure, S C George
Biocompatible polymers, such as polydimethylsiloxane (PDMS), are the materials of choice for creating organ-on-a-chip microfluidic platforms. Desirable qualities include ease of fabrication, optical clarity, and hydrophobicity, the latter of which facilitates oxygen transport to encased cells. An emerging and important application of organ-on-a-chip technology is drug discovery; however, a potential issue for polymer-based microfluidic devices has been highlighted by recent studies with PDMS, which have demonstrated absorption (and thus loss) of hydrophobic drugs into PDMS under certain experimental conditions...
January 19, 2017: Lab on a Chip
https://www.readbyqxmd.com/read/28102858/luminescent-immunoprecipitation-system-lips-for-detection-of-autoantibodies-against-atp4a-and-atp4b-subunits-of-gastric-proton-pump-h-k-atpase-in-atrophic-body-gastritis-patients
#20
Edith Lahner, Cristina Brigatti, Ilaria Marzinotto, Marilia Carabotti, Giulia Scalese, Howard W Davidson, Janet M Wenzlau, Emanuele Bosi, Lorenzo Piemonti, Bruno Annibale, Vito Lampasona
OBJECTIVES: Circulating autoantibodies targeting the H+/K+-ATPase proton pump of gastric parietal cells are considered markers of autoimmune gastritis, whose diagnostic accuracy in atrophic body gastritis, the pathological lesion of autoimmune gastritis, remains unknown. This study aimed to assess autoantibodies against ATP4A and ATP4B subunits of parietal cells H+, K+-ATPase in atrophic body gastritis patients and controls. METHODS: One-hundred and four cases with atrophic body gastritis and 205 controls were assessed for serological autoantibodies specific for ATP4A or ATP4B subunits using luminescent immunoprecipitation system (LIPS)...
January 19, 2017: Clinical and Translational Gastroenterology
keyword
keyword
84460
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"