Abstract:
:Coherent x-rays from synchrotron sources are increasingly used in non-conventional radiological techniques ('phase-contrast' radiology). Our experiments demonstrate that by using white (unmonochromatic) radiation and a time-resolving system, it is possible to image microscopic details of moving blood vessels in different live animals without using any contrast agent. The images have excellent contrast plus unprecedented spatial resolution for microangiography (< 10 microm). This result is likely to impact many different areas of biological and medical research and of diagnostic radiology.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Hwu Y,Tsai WL,Je JH,Seol SK,Kim B,Groso A,Margaritondo G,Lee KH,Seong JKdoi
10.1088/0031-9155/49/4/002subject
Has Abstractpub_date
2004-02-21 00:00:00pages
501-8issue
4eissn
0031-9155issn
1361-6560journal_volume
49pub_type
杂志文章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
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journal_title:Physics in medicine and biology
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journal_title:Physics in medicine and biology
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journal_title:Physics in medicine and biology
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abstract::Ion chamber dosimetry requires a high degree of precision, at all steps within the dosimetric process, in order to ensure accurate dose measurements. This work presents a novel technique for ion chamber volume determination and quality assurance, using micro-computed tomography (micro-CT). Four nominally identical Exr...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/53/18/012
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abstract::A number of radiation-therapy-related uses based on a commercially available spreadsheet program have been developed at our facility. The graphics and display capabilities inherent in these spreadsheet programs allow for concise visual results. The spreadsheets are used as an independent check for several types of rad...
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pub_type: 杂志文章
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abstract::Fluorescence diffuse optical tomography (fDOT) provides 3D images of fluorescence distributions in biological tissue, which represent molecular and cellular processes. The image reconstruction problem is highly ill-posed and requires regularisation techniques to stabilise and find meaningful solutions. Quadratic regul...
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journal_title:Physics in medicine and biology
pub_type: 历史文章,杂志文章
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abstract::Monte Carlo simulation techniques are applied to track the annihilation photons from positron decay, and store the photon histories. Reasonably realistic models of the isotope distribution in the brain and heart during typical PET studies, as well as the traditional phantoms used for measuring PET scanner performance ...
journal_title:Physics in medicine and biology
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abstract::New definitions of the absorbed dose conversion factors Clambda and CE are proposed. The absorbed dose in water is given by the product of absorbed dose conversion factor, exposure calibration factor, ionisation chamber reading, cap displacement correction factor and perturbation correction factor. At exposure calibra...
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journal_title:Physics in medicine and biology
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更新日期:1980-01-01 00:00:00
abstract::With high-dose administration of (90)Y labeled antibodies, it is possible to image (90)Y without an admixture of (111)In. We have earlier shown that it is possible to perform quantitative (90)Y bremsstrahlung SPECT for dosimetry purposes with reasonable accuracy. However, whole-body (WB) activity quantification with t...
journal_title:Physics in medicine and biology
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/52/3/007
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abstract::The prompt-gamma neutron activation facility at Brookhaven National Laboratory was upgraded to improve both the precision and accuracy of its in vivo determinations of total body nitrogen. The upgrade, guided by Monte Carlo simulations, involved elongating and modifying the source collimator and its shielding, reposit...
journal_title:Physics in medicine and biology
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journal_title:Physics in medicine and biology
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journal_title:Physics in medicine and biology
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abstract::Grating interferometry is advantageous over conventional x-ray absorption imaging because it enables the detection of samples constituted by low atomic number elements (low-Z materials). Therefore, it has a potential application in biological science and medical diagnostics. The grating interferometry has some critica...
journal_title:Physics in medicine and biology
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journal_title:Physics in medicine and biology
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abstract::It has been reported that the dose effects of metallic guidewires are significant in intravascular brachytherapy (IVBT) using a beta source. The purpose of this work is to investigate the dependence of these dose effects on guidewire position. The EGS4 Monte Carlo codes were used to perform the dose calculations for t...
journal_title:Physics in medicine and biology
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journal_title:Physics in medicine and biology
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journal_title:Physics in medicine and biology
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journal_title:Physics in medicine and biology
pub_type: 传,历史文章,杂志文章,评审
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abstract::The whole prostatic volume (PV) is an important indicator for benign prostate hyperplasia. Correlating the PV with other clinical parameters in a population-based prospective cohort study (SHIP-2) requires valid prostate segmentation in a large number of whole-body MRI scans. The axial proton density fast spin echo fa...
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
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更新日期:2021-01-20 00:00:00
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journal_title:Physics in medicine and biology
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journal_title:Physics in medicine and biology
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abstract::Quantifying the retention or washout of (99m)Tc-Sestamibi (MIBI) in breast tumours in vivo may provide a basis for predicting the chemotherapy response. The aim of this study is to investigate the variations and limitations of the different methods used to quantify these parameters. A phantom was developed that allowe...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
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