A novel description of FDG excretion in the renal system: application to metformin-treated models.

abstract：:Gas target systems have been used for decades on cyclotrons to produce radionuclides for medical imaging. However, the activity recovered from such targets is often lower than its theoretically predicted value. Past research has suggested that nuclide interactions with the walls of the target body may play a key role ...

journal_title：Physics in medicine and biology

authors： Zacchia NA,Buckley KR,Martinez GM,Ruth TJ,Martinez DM,Hoehr C

更新日期：2018-09-28 00:00:00

abstract：:Uncemented prosthetic joint implants used in orthopaedic surgery are usually coated with a porous surface to encourage bone ingrowth. Better contact between the endosteal bone and the porous surface improves ingrowth, and such contact may be increased if the joint further subsides into position in the first weeks foll...

journal_title：Physics in medicine and biology

authors： Berry E,Langkamer VG,Jackson PC,Snow M,Goddard PR,Wells PN

更新日期：1993-02-01 00:00:00

abstract：:In this study, we explore the potential of compressed sensing (CS) accelerated broadband 3D phase-encoded turbo spin-echo (3D-PE-TSE) for the purpose of geometrically undistorted imaging in the presence of field inhomogeneities. To achieve this goal 3D-PE-SE and 3D-PE-TSE sequences with broadband rf pulses and dedicat...

journal_title：Physics in medicine and biology

authors： van Gorp JS,Bakker CJ,Bouwman JG,Smink J,Zijlstra F,Seevinck PR

更新日期：2015-01-21 00:00:00

abstract：:A bilateral comparison of national dosimetric standards for high dose rate brachytherapy has been conducted between the Laboratoire National Henri Becquerel and the University of Wisconsin Accredited Dosimetry Calibration Laboratory. A complete overview of the methods that are currently in use to establish the two nat...

journal_title：Physics in medicine and biology

authors： Douysset G,Gouriou J,Delaunay F,DeWerd L,Stump K,Micka J,Laboratoire National Henri Becquerel.,University of Wisconsin Accredited Dosimetry Calibration Laboratory.

更新日期：2005-05-07 00:00:00

abstract：:The design and performance of a dosimetric system for the irradiation of thin biological samples with therapeutic proton beams is reported. Protons with initial energies between 40 MeV and 250 MeV are degraded with polystyrene blocks of variable thickness in order to place the sample, an aqueous layer of 10 microm thi...

journal_title：Physics in medicine and biology

authors： Bashkirov V,Schulte RW

更新日期：2002-02-07 00:00:00

abstract：:Various forms of GAFChromic film have been used for several years as radiographic media for measuring dose distributions of brachytherapy sources and small radiation fields. Upon irradiation the film changes colour and darkens with time post-irradiation. The darkening is most rapid in the first 24 h, and it has been s...

journal_title：Physics in medicine and biology

authors： Reinstein LE,Gluckman GR,Meek AG

更新日期：1998-10-01 00:00:00

abstract：:In addition to being a powerful clinical tool, Positron emission tomography (PET) is also used in small laboratory animal research to visualize and track certain molecular processes associated with diseases such as cancer, heart disease and neurological disorders in living small animal models of disease. However, dosi...

journal_title：Physics in medicine and biology

authors： Xie T,Zaidi H

更新日期：2013-01-07 00:00:00

abstract：:Dose reconstruction is a process that re-creates the treatment-time dose deposited in a patient provided there is knowledge of the delivered energy fluence and the patient's anatomy at the time of treatment. A method for reconstructing dose is presented. The process starts with delivery verification, in which the inci...

journal_title：Physics in medicine and biology

authors： Kapatoes JM,Olivera GH,Balog JP,Keller H,Reckwerdt PJ,Mackie TR

更新日期：2001-04-01 00:00:00

abstract：:Elevated interstitial fluid pressure is one of the barriers of drug delivery in solid tumors. Recent studies have shown that normalization of tumor vasculature by anti-angiogenic factors may improve the delivery of conventional cytotoxic drugs, possibly by increasing blood flow, decreasing interstitial fluid pressure,...

journal_title：Physics in medicine and biology

authors： Ozturk D,Yonucu S,Yilmaz D,Unlu MB

更新日期：2015-02-21 00:00:00

abstract：:The objective of this paper is to evaluate an iterative maximum likelihood (ML) cone-beam computed tomography (CBCT) reconstruction with total variation (TV) regularization with respect to the robustness of the algorithm due to data inconsistencies. Three different and (for clinical application) typical classes of err...

journal_title：Physics in medicine and biology

authors： Stsepankou D,Arns A,Ng SK,Zygmanski P,Hesser J

更新日期：2012-10-07 00:00:00

abstract：:A three-dimensional (3D) point-kernel multiple scatter model for point spread function (PSF) determination in parallel-beam single-photon emission computed tomography (SPECT), based on a dose gamma-ray buildup factor, is proposed. This model embraces nonuniform attenuation in a voxelized object of imaging (patient bod...

journal_title：Physics in medicine and biology

authors： Marinkovic P,Ilic R,Spaic R

更新日期：2007-10-07 00:00:00

abstract：:The electrostimulation excitation threshold of a nerve depends on temporal and frequency parameters of the stimulus. These dependences were investigated in terms of: (1) strength-duration (SD) curve for a single monophasic rectangular pulse, and (2) frequency dependence of the excitation threshold for a continuous sin...

journal_title：Physics in medicine and biology

authors： Šarolić A,Živković Z,Reilly JP

更新日期：2016-06-21 00:00:00

abstract：:The concepts of radiance and fluence are fundamental to the description of a radiation field. The International Commission on Radiological Units and Measurements (ICRU) has defined fluence in terms of the number of the radiation particles crossing a small sampling sphere. A second definition has been proposed in which...

journal_title：Physics in medicine and biology

authors： Papiez L,Battista JJ

更新日期：1994-06-01 00:00:00

abstract：:Tserng and Kalhan have raised the question of the appropriate equation to use for the measurement of turnover rate in a stable-isotope study. In a comparison of glucose turnover measured with 2H-glucose and with 13C-glucose they used five apparently different equations and obtained conflicting answers. There is, howev...

journal_title：Physics in medicine and biology

authors： Wootton R,Ford GC,Cheng KN,Halliday D

更新日期：1985-10-01 00:00:00

abstract：:The 50-year tenure of Physics in Medicine and Biology has coincided with some of the most important developments in radiological science, including the introduction of artificial radioactivity, computers and 3D imaging into medicine. These events have profoundly influenced the development of brachytherapy. Although it...

journal_title：Physics in medicine and biology

authors： Williamson JF

更新日期：2006-07-07 00:00:00

abstract：:Monte Carlo simulation was used to calculate correction factors for output factor (OF), percentage depth-dose (PDD), and off-axis ratio (OAR) measurements with the CyberKnife M6 System. These include the first such data for the InCise MLC. Simulated detectors include diodes, air-filled microchambers, a synthetic micro...

journal_title：Physics in medicine and biology

authors： Francescon P,Kilby W,Noll JM,Masi L,Satariano N,Russo S

更新日期：2017-02-07 00:00:00

abstract：:A classical trajectory model has been used to predict total cross sections of single and double ionizing processes (including capture processes) for several ion-biological molecule collisional systems in the intermediate and high energy range. In this work, the systems studied are water, adenine or cytosine targets io...

journal_title：Physics in medicine and biology

authors： Abbas I,Champion C,Zarour B,Lasri B,Hanssen J

更新日期：2008-02-21 00:00:00

abstract：:In dual energy x-ray absorptiometry (DXA) the photon attenuation is assumed to be similar in soft tissue overlying, adjacent to and inside the measured bone. In the calcaneal dual energy x-ray laser (DXL) technique, this assumption is not needed as attenuation by soft tissues at the local bone site is determined by co...

journal_title：Physics in medicine and biology

authors： Hakulinen MA,Saarakkala S,Töyräs J,Kröger H,Jurvelin JS

更新日期：2003-06-21 00:00:00

abstract：:A general theory is presented for minimizing noise in linear dimension reduction of sequences of medical images when the factors and the covariance matrix and mean of the noise are given. A dimension reduction is optimal when all diagonal elements in the covariance matrix of the noise in the signal (factor) space are ...

journal_title：Physics in medicine and biology

authors： Hermansen F,Lammertsma AA

更新日期：1995-11-01 00:00:00

abstract：:Respiratory motion can blur the tomographic reconstruction of positron emission tomography or single-photon emission computed tomography (SPECT) images, which subsequently impair quantitative measurements, e.g. in the upper abdomen area. Respiratory signal phase-based gated reconstruction addresses this problem, but d...

journal_title：Physics in medicine and biology

authors： Breuilly M,Malandain G,Guglielmi J,Marsault R,Pourcher T,Franken PR,Darcourt J

更新日期：2013-04-21 00:00:00

abstract：:In order to effectively utilize the prominent properties of heavy ions in radiotherapy, it is important to evaluate both the position of the field irradiated with incident ions and the absorbed dose distribution in a patient's body. One of the methods for this purpose is the utilization of the positron emitters produc...

journal_title：Physics in medicine and biology

authors： Inaniwa T,Kohno T,Tomitani T,Sato S

更新日期：2008-02-07 00:00:00

abstract：:Although field area and object thickness are important parameters in comparisons of techniques for optimal reduction of scattered radiation to the image, they are in practice seldom varied. For this reason, we suggest that contrast degradation (CDF) and contrast improvement (CIF) factors be more frequently used and ap...

journal_title：Physics in medicine and biology

authors： Carlsson GA,Carlsson CA,Nielsen B,Persliden J

更新日期：1986-07-01 00:00:00

abstract：:In this work, we propose a framework for optimizing spectral CT imaging parameters and hardware design with regard to material classification tasks. Compared with conventional CT, many more parameters must be considered when designing spectral CT systems and protocols. These choices will impact material classification...

journal_title：Physics in medicine and biology

authors： Rigie DS,La Rivière PJ

更新日期：2016-06-21 00:00:00

abstract：:In external beam radiation therapy, radioactive beams offer the best clinical solution to simultaneously treat and in vivo monitor the dose delivery and tumor response using PET or PET-CT imaging. However, difficulties mainly linked to the low production efficiency have so far limited their use. This study is devoted ...

journal_title：Physics in medicine and biology

authors： Lazzeroni M,Brahme A

更新日期：2011-03-21 00:00:00

abstract：:The process of organ motion correction in scintigraphy is analysed in the frequency domain. The sequence of the chi- and gamma- coordinates registered during scintigraphic recording is converted to a frequency spectrum by a discrete Fourier transform. In the frequency domain motion correction is performed by linear fi...

journal_title：Physics in medicine and biology

authors： Schmidlin P

更新日期：1975-05-01 00:00:00

abstract：:The use of calibrated tissue-equivalent (TE) ionisation chambers is commonly considered to be the most practical method for total absorbed dose determinations in mixed neutron-photon fields for biomedical applications. The total absorbed dose can be derived from the charge produced within the cavity of an ionisation c...

journal_title：Physics in medicine and biology

authors： Zoetelief J,Broerse JJ

更新日期：1983-05-01 00:00:00

abstract：:We propose a hybrid multiobjective (MO) evolutionary optimization algorithm (MOEA) for intensity-modulated radiotherapy inverse planning and apply it to optimize the number of incident beams, their orientations and intensity profiles. The algorithm produces a set of efficient solutions, which represent different clini...

journal_title：Physics in medicine and biology

authors： Schreibmann E,Lahanas M,Xing L,Baltas D

更新日期：2004-03-07 00:00:00

abstract：:We evaluated the basic properties of a commercially available BANGkit gel dosimeter, which is a normoxic type of BANG gel. This gel-kit has the same composition as the BANG 3 gel, but is fully oxygenated. To exclude oxygen, oxygen scavenging ascorbic acid and copper sulfate as a catalyst are used. The properties that ...

journal_title：Physics in medicine and biology

authors： Murakami Y,Nakashima T,Watanabe Y,Akimitsu T,Matsuura K,Kenjo M,Kaneyasu Y,Wadasaki K,Hirokawa Y,Ito K

更新日期：2007-04-21 00:00:00

abstract：:The purpose of this investigation is to propose new compensator design strategies for protons and heavier particles which are based on pencil-beam (PB) dose calculations and which significantly reduce the dose to tissues downstream from the target, yet provide acceptable target coverage under conditions of patient mot...

journal_title：Physics in medicine and biology

authors： Petti PL

更新日期：1997-07-01 00:00:00

abstract：:Values of the relative permittivity and conductivity of the rabbit retina and lens have been measured between 10 MHz and 10 GHz over the temperature range 20 to -20 degrees C. As the temperature was lowered from 20 degrees C the dielectric parameters changed smoothly until -9 degrees C where freezing occurred. At this...

journal_title：Physics in medicine and biology

authors： Gabriel C,Grant EH

更新日期：1985-09-01 00:00:00