Log in

Relevant bibliographies by topics / High resolution ultrasound spectroscopy / Journal articles

To see the other types of publications on this topic, follow the link: High resolution ultrasound spectroscopy.

Journal articles on the topic 'High resolution ultrasound spectroscopy'

Author: Grafiati

Published: 28 June 2021

Last updated: 4 February 2022

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 journal articles for your research on the topic 'High resolution ultrasound spectroscopy.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.

1

Hoe, Susan, Paul M. Young, Philippe Rogueda, and Daniela Traini. "Determination of Reference Ultrasound Parameters for Model and Hydrofluoroalkane Propellants Using High-Resolution Ultrasonic Spectroscopy." AAPS PharmSciTech 9, no. 2 (May 6, 2008): 605–11. http://dx.doi.org/10.1208/s12249-008-9087-z.

Full text

APA, Harvard, Vancouver, ISO, and other styles

2

Griffin, J. L., and O. Corcoran. "High-resolution magic-angle spinning 13C NMR spectroscopy of cerebral tissue." Magnetic Resonance Materials in Physics, Biology and Medicine 18, no. 1 (February 10, 2005): 51–56. http://dx.doi.org/10.1007/s10334-004-0094-0.

Full text

APA, Harvard, Vancouver, ISO, and other styles

3

Miraux, Sylvain, Gérard Raffard, Laurent Pothuaud, Laure De Taillac, Joelle Amédée, Paul Canioni, Eric Thiaudière, and Jean-Michel Franconi. "NMR microscopy with a high-resolution liquid-state spectroscopy probe." Concepts in Magnetic Resonance Part B: Magnetic Resonance Engineering 25B, no. 1 (April 2005): 12–17. http://dx.doi.org/10.1002/cmr.b.20030.

Full text

APA, Harvard, Vancouver, ISO, and other styles

4

Sitter, Beathe, Tone Bathen, Bj� �rn Hagen, Cecilie Arentz, Finn Egil Skjeldestad, and Ingrid S. Gribbestad. "Cervical cancer tissue characterized by high-resolution magic angle spinning MR spectroscopy." MAGMA Magnetic Resonance Materials in Physics, Biology and Medicine 16, no. 4 (March 1, 2004): 174–81. http://dx.doi.org/10.1007/s10334-003-0025-5.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

MacRitchie, Neil, Gianluca Grassia, Jonathan Noonan, Paul Garside, Duncan Graham, and Pasquale Maffia. "Molecular imaging of atherosclerosis: spotlight on Raman spectroscopy and surface-enhanced Raman scattering." Heart 104, no. 6 (October 23, 2017): 460–67. http://dx.doi.org/10.1136/heartjnl-2017-311447.

Full text

Abstract:

To accurately predict atherosclerotic plaque progression, a detailed phenotype of the lesion at the molecular level is required. Here, we assess the respective merits and limitations of molecular imaging tools. Clinical imaging includes contrast-enhanced ultrasound, an inexpensive and non-toxic technique but with poor sensitivity. CT benefits from high spatial resolution but poor sensitivity coupled with an increasing radiation burden that limits multiplexing. Despite high sensitivity, positron emission tomography and single-photon emission tomography have disadvantages when applied to multiplex molecular imaging due to poor spatial resolution, signal cross talk and increasing radiation dose. In contrast, MRI is non-toxic, displays good spatial resolution but poor sensitivity. Preclinical techniques include near-infrared fluorescence (NIRF), which provides good spatial resolution and sensitivity; however, multiplexing with NIRF is limited, due to photobleaching and spectral overlap. Fourier transform infrared spectroscopy and Raman spectroscopy are label-free techniques that detect molecules based on the vibrations of chemical bonds. Both techniques offer fast acquisition times with Raman showing superior spatial resolution. Raman signals are inherently weak; however, leading to the development of surface-enhanced Raman spectroscopy (SERS) that offers greatly increased sensitivity due to using metallic nanoparticles that can be functionalised with biomolecules targeted against plaque ligands while offering high multiplexing potential. This asset combined with high spatial resolution makes SERS an exciting prospect as a diagnostic tool. The ongoing refinements of SERS technologies such as deep tissue imaging and portable systems making SERS a realistic prospect for translation to the clinic.

APA, Harvard, Vancouver, ISO, and other styles

6

Jugl, Adam, and Miloslav Pekař. "Hyaluronan-Arginine Interactions—An Ultrasound and ITC Study." Polymers 12, no. 9 (September 12, 2020): 2069. http://dx.doi.org/10.3390/polym12092069.

Full text

Abstract:

High-resolution ultrasound spectroscopy and isothermal titration calorimetry were used to characterize interactions between hyaluronan and arginine oligomers. The molecular weight of arginine oligomer plays an important role in interactions with hyaluronan. Interactions were observable for arginine oligomers with eight monomer units and longer chains. The effect of the ionic strength and molecular weight of hyaluronan on interactions was tested. In an environment with increased ionic strength, the length of the arginine oligomer was crucial. Generally, sufficiently high ionic strength suppresses interactions between hyaluronan and arginine oligomers, which demonstrated interactions in water. From the point of view of the molecular weight of hyaluronan, the transition between the rod conformation and the random coil conformation appeared to be important.

APA, Harvard, Vancouver, ISO, and other styles

7

WANG, HUI, YINONG LU, and JUNJIE ZHU. "PREPARATION OF CUBE-SHAPED CdS NANOPARTICLES BY SONOCHEMICAL METHOD." International Journal of Nanoscience 01, no. 05n06 (October 2002): 437–41. http://dx.doi.org/10.1142/s0219581x02000462.

Full text

Abstract:

Cube-shaped CdS nanoparticles have been successfully prepared by a sonochemical method in an oil-in-water microemulsion. The product was characterized by using techniques including X-ray powder diffraction, high-resolution transmission electron microscopy, energy-dispersive X-ray analysis and UV-visible absorption spectroscopy. This microemulsion system in the presence of high-intensity ultrasound irradiation provides special conditions for the nucleation and growth of the CdS nanoparticles.

APA, Harvard, Vancouver, ISO, and other styles

8

Mouly-Bandini, A., J. Vion-Dury, P. Viout, M. Sciaky, T. Mesana, and P. J. Cozzone. "Detection of acute cardiac rejection by high resolution proton magnetic resonance spectroscopy of plasma." Magma: Magnetic Resonance Materials in Physics, Biology, and Medicine 11, no. 1 (February 2000): 27–32. http://dx.doi.org/10.1007/bf02678486.

Full text

APA, Harvard, Vancouver, ISO, and other styles

9

Pippa, Natassa, Diego Romano Perinelli, Stergios Pispas, Giulia Bonacucina, Costas Demetzos, Aleksander Forys, and Barbara Trzebicka. "Studying the colloidal behavior of chimeric liposomes by cryo-TEM, micro-differential scanning calorimetry and high-resolution ultrasound spectroscopy." Colloids and Surfaces A: Physicochemical and Engineering Aspects 555 (October 2018): 539–47. http://dx.doi.org/10.1016/j.colsurfa.2018.07.025.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Si, Wei, Chao Ding, and Siqi Ding. "Synthesis and Characterization of YAG Nanoparticles by Ultrasound-Assisted and Ultrasound-Microwave-Assisted Alkoxide Hydrolysis Precipitation Methods." Journal of Nanomaterials 2014 (2014): 1–8. http://dx.doi.org/10.1155/2014/408910.

Full text

Abstract:

Yttrium aluminum garnet (YAG, Y3Al5O12) nanoparticles were synthesized by ultrasound-assisted and ultrasound-microwave-assisted alkoxide hydrolysis precipitation methods. The effect of reaction parameters including pH value, ultrasonic radiation time, and calcination temperature on the composition of the products was investigated. The YAG nanoparticles and their precursor were characterized by X-ray powder diffraction (XRD), differential thermal analysis (DTA), Fourier-transform infrared spectroscopy (FT-IR), and high-resolution transmission electron microscopy (HRTEM). The results show that the single ultrasound-assisted method to synthesize YAG phase often contains intermediate phases of YAM (Y4Al2O9) and YAP (YAlO3); pure YAG phase can form only at special conditions and as single crystal. The pure phase YAG powders can be obtained at each experimental condition when using ultrasound-microwave-assisted synthesis and the grain is polycrystalline. This is due to the microwave radiation which promotes atomic diffusion and forms a lot of crystal nuclei of YAG in the precursor. The YAG nanoparticles with a grain size of 18 nm can be obtained at a calcination temperature of 900°C when using ultrasound-microwave-assisted method.

APA, Harvard, Vancouver, ISO, and other styles

11

Musa, Corentin, Pierre-Edouard Danjou, Antoine Pauwels, Francine Cazier-Dennin, and François Delattre. "Ultrasound-Assisted Heterogeneous Synthesis of Bio-Based Oligo-Isosorbide Glycidyl Ethers: Towards Greener Epoxy Precursors." Molecules 24, no. 9 (April 26, 2019): 1643. http://dx.doi.org/10.3390/molecules24091643.

Full text

Abstract:

The substitution of toxic precursors such as bisphenol A by renewable and safer molecules has become a major challenge. To overcome this challenge, the 12 principles of green chemistry should be taken into account in the development of future sustainable chemicals and processes. In this context, this paper reports the highly efficient synthesis of oligo-isosorbide glycidyl ethers from bio-based starting materials by a rapid one-pot heterogeneous ultrasound-assisted synthesis. It was demonstrated that the use of high-power ultrasound in solvent-free conditions with sodium hydroxide microbeads led for the first time to a fully epoxidated prepolymer with excellent epoxy equivalent weight (EEW). The structure of the epoxy precursor was characterized by FT-IR, NMR spectroscopy and high-resolution mass spectrometry (HRMS). The efficiency of the ultrasound-assisted synthesis was attributed to the physical effects caused by micro-jets on the surface of the solid sodium hydroxide microspheres following the asymmetrical collapse of cavitation bubbles.

APA, Harvard, Vancouver, ISO, and other styles

12

Štengl, Václav, Jiří Henych, and Michaela Slušná. "h-BN-TiO2Nanocomposite for Photocatalytic Applications." Journal of Nanomaterials 2016 (2016): 1–12. http://dx.doi.org/10.1155/2016/4580516.

Full text

Abstract:

h-BN-TiO2nanocomposites were synthesized by the thermal hydrolysis of titanium peroxo-complexes in the presence of exfoliated h-BN. The bulk h-BN was prepared by annealing mixture of boric acid and urea, and high intensity ultrasound was used for its exfoliation. The prepared samples were characterized by X-ray powder diffraction (XRD), infrared spectroscopy, Raman spectroscopy, electron spin resonance (ESR), high resolution electron microscopy, BET surface area, and BJH porosity measurement. The UV-Vis diffuse reflectance spectroscopy was employed to estimate band-gap energies. The photoinduced charge on the surface of h-BN-TiO2nanocomposites was visualized using electric force microscopy (EFM). The photocatalytic activity was determined by azo dyes Orange II and Reactive Black 5 photobleaching. The highest rate constantk= 0.0762 min−1and 0.0164 min−1, under UV and visible light irradiation, respectively, showed sample denoted TiP050BN with moderate concentration of h-BN.

APA, Harvard, Vancouver, ISO, and other styles

13

Jung, Joon Min, Ji Young Cho, Woo Jin Lee, Sung Eun Chang, Mi Woo Lee, and Chong Hyun Won. "Emerging Minimally Invasive Technologies for the Detection of Skin Cancer." Journal of Personalized Medicine 11, no. 10 (September 24, 2021): 951. http://dx.doi.org/10.3390/jpm11100951.

Full text

Abstract:

With the increasing incidence of skin cancer, many noninvasive technologies to detect its presence have been developed. This review focuses on reflectance confocal microscopy (RCM), optical coherence tomography (OCT), high-frequency ultrasound (HFUS), electrical impedance spectroscopy (EIS), pigmented lesion assay (PLA), and Raman spectroscopy (RS) and discusses the basic principle, clinical applications, advantages, and disadvantages of each technology. RCM provides high cellular resolution and has high sensitivity and specificity for the diagnosis of skin cancer. OCT provides lower resolution than RCM, although its evaluable depth is deeper than that of RCM. RCM and OCT may be useful in reducing the number of unnecessary biopsies, evaluating the tumor margin, and monitoring treatment response. HFUS can be mainly used to delineate tumor depths or margins and monitor the treatment response. EIS provides high sensitivity but low specificity for the diagnosis of skin malignancies. PLA, which is based on the genetic information of lesions, is applicable for the detection of melanoma with high sensitivity and moderate-to-high specificity. RS showed high accuracy for the diagnosis of skin cancer, although more clinical studies are required. Advances in these technologies for the diagnosis of skin cancer can lead to the realization of optimized and individualized treatments.

APA, Harvard, Vancouver, ISO, and other styles

14

Hernandez-Pichardo, M. L., M. A. Valenzuela, S. P. Paredes, P. Del Angel, and J. A. Montoya De la Fuente. "Ni/ZrO₂-CeO₂ Catalysts for the Simultaneous Production of Hydrogen and Carbon Nanotubes." Journal of New Materials for Electrochemical Systems 14, no. 2 (April 7, 2011): 127–31. http://dx.doi.org/10.14447/jnmes.v14i2.121.

Full text

Abstract:

The catalytic methane decomposition (CMD) using Ni/ZrO2-CeO2 catalysts for the simultaneous production of hydrogen and carbon nanotubes, was studied on samples prepared by different synthesis methods. The catalysts were synthesized by the impregnation and coprecipitation methods with or without ultrasound treatment. X-ray diffraction (XRD), Raman spectroscopy and high resolution transmission electron microscopy (HRTEM) were the main characterization techniques. It was observed that the Ni impregnated catalyst with ultrasound treatment increases significantly the production of hydrogen and carbon nanotubes in the CDM at 500 °C. The results also indicated that the synthesis of catalysts via coprecipitation generates a higher number of encapsulated Ni particles by both, the ZrO2-CeO2 support and the produced carbon at the end of the reaction.

APA, Harvard, Vancouver, ISO, and other styles

15

Vegh, Viktor, Hector Sanchez, Ian M. Brereton, and Stuart Crozier. "Toward designing asymmetric head gradient coils for high-resolution imaging." Concepts in Magnetic Resonance Part B: Magnetic Resonance Engineering 31B, no. 1 (2007): 1–11. http://dx.doi.org/10.1002/cmr.b.20082.

Full text

APA, Harvard, Vancouver, ISO, and other styles

16

Passeri, Alessandro, Stefano Mazzuca, and Veronica Del Bene. "Radiofrequency field inhomogeneity compensation in high spatial resolution magnetic resonance spectroscopic imaging." Physics in Medicine and Biology 59, no. 12 (May 15, 2014): 2913–34. http://dx.doi.org/10.1088/0031-9155/59/12/2913.

Full text

APA, Harvard, Vancouver, ISO, and other styles

17

Mao, Meijun, Minqing Zhang, Wei Xu, and Bei Zhao. "Design and development of peptide-functionalized iron oxide nanoparticles: Investigation of ultrasound imaging for the diagnosis and treatment of cancers." Materials Express 11, no. 6 (June 1, 2021): 817–23. http://dx.doi.org/10.1166/mex.2021.1990.

Full text

Abstract:

Iron oxide nanoparticles (Fe3O4 NPs) with superparamagnetic characteristics were synthesized and coated with glypican-3 ligand peptide (GPC3), resulting in GPC3@Fe3O4 NPs. Fourier-transform infrared spectroscopy and high resolution transmission electron microscopy (HRTEM) were used to characterize the fabricated GPC3@Fe3O4 NPs, and dynamic light scattering measurements were performed to determine the average particle surface charge. The morphology and size distributions of the uncoated Fe3O4 NPs were determined using HRTEM images, which revealed uniform-sized GPC3@Fe3O4 NPs with a particle size of approximately 10 nm. An in vitro cell proliferation assay was performed on non-cancerous HEK-293 cells to examine the cytotoxicity of free Fe3O4 NPs, free GPC3, and GPC3@Fe3O4 NPs. The potential of the engineered GPC3@Fe3O4 NPs to act as contrast agents for enhanced ultrasound imaging was also examined in vitro. The results showed that GPC3@Fe3O4 NPs significantly improved the effective ultrasound contrast analysis for cancer detection and treatment.

APA, Harvard, Vancouver, ISO, and other styles

18

van Asten, Jack J. A., Vincent Cuijpers, Christina Hulsbergen-van de Kaa, Claudia Soede-Huijbregts, J. Alfred Witjes, Albert Verhofstad, and Arend Heerschap. "High resolution magic angle spinning NMR spectroscopy for metabolic assessment of cancer presence and Gleason score in human prostate needle biopsies." Magnetic Resonance Materials in Physics, Biology and Medicine 21, no. 6 (November 2008): 435–42. http://dx.doi.org/10.1007/s10334-008-0156-9.

Full text

APA, Harvard, Vancouver, ISO, and other styles

19

Seo, Youngseob. "High spatial resolution magnetic resonance imaging of insects covered with a hard exoskeleton." Concepts in Magnetic Resonance Part B: Magnetic Resonance Engineering 48B, no. 1 (February 2018): e21366. http://dx.doi.org/10.1002/cmr.b.21366.

Full text

APA, Harvard, Vancouver, ISO, and other styles

20

Stenman, Katarina, Jón B. Hauksson, Gerhard Gröbner, Pär Stattin, Anders Bergh, and Katrine Riklund. "Detection of polyunsaturated omega-6 fatty acid in human malignant prostate tissue by 1D and 2D high-resolution magic angle spinning NMR spectroscopy." Magnetic Resonance Materials in Physics, Biology and Medicine 22, no. 6 (November 17, 2009): 327–31. http://dx.doi.org/10.1007/s10334-009-0187-x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

21

Arunachalam, Thirunavukkarasu, Muthukumaran Karpagasundaram, and Nithya Rajarathinam. "Ultrasound assisted green synthesis of cerium oxide nanoparticles using Prosopis juliflora leaf extract and their structural, optical and antibacterial properties." Materials Science-Poland 35, no. 4 (March 20, 2018): 791–98. http://dx.doi.org/10.1515/msp-2017-0104.

Full text

Abstract:

Abstract Cerium oxide nanoparticles (CONPs) were prepared using ultrasound assisted leaf extract of Prosopis juliflora acting as a reducing as well as stabilizing agent. The synthesized CONPs were characterized by ultraviolet-visible absorption spectroscopy (UV-Vis), particle size analyzer (PSA), Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and high-resolution transmission electron microscopy (HRTEM). From the UV-Vis analysis, the optical band gap of the prepared CONPs (Eg = 3.62 eV) was slightly increased as compared to the bulk ceria (Eg = 3.19 eV). The phytochemicals in the extract reduced the particle size to 3.7 nm ± 0.3 nm, as it is evident from the PSA. FT-IR results confirmed the Ce-O stretching bands by showing the peaks at 452 cm-1. The Raman spectrumshowed a characteristic peak shift for CONPs at 461.2 cm-1. XRD analysis revealed the cubic fluorite structure of the synthesizednanoparticles with the lattice constant, a of 5.415 Å and unit cell volume, V of 158.813 Å3. XPS signals were used to determine the concentration of Ce3+ and Ce4+ in the prepared CONPs and it was found that major amount of cerium exist in the Ce4+ state. HRTEM images showed spherical shaped particles with an average size of 15 nm. Furthermore, the antibacterial activity of the prepared CONPs was evaluated and their efficacies were compared with the conventional antibiotics using disc diffusion assay against a set of Gram positive (G+) bacteria (Staphylococcus aureus, Streptococcus pneumonia) and Gram negative (G-) bacteria (Pseudomonas aeruginosa, Proteus vulgaris). The results suggested that CONPs showed antibacterial activity with significant variations due to the differences in the membrane structure and cell wall composition among the two groups tested.

APA, Harvard, Vancouver, ISO, and other styles

22

Stanisz, Ewa, and Magdalena Krawczyk-Coda. "ZnO nanoparticles as an adsorbent in ultrasound-assisted dispersive micro solid-phase extraction combined with high-resolution continuum source electrothermal atomic absorption spectrometry for determination of trace germanium in food samples." Microchemical Journal 132 (May 2017): 136–42. http://dx.doi.org/10.1016/j.microc.2017.01.018.

Full text

APA, Harvard, Vancouver, ISO, and other styles

23

Dowlatshahi, K., and J. Dieschbourg. "Shift in the surgical treatment of non-palpable breast cancer: tactile to visual." Breast Cancer Online 9, no. 1 (January 2006): 1–10. http://dx.doi.org/10.1017/s1470903105003755.

Full text

Abstract:

Increasing number of small, early-staged breast cancers are detected by screening mammography. Diagnosis and determination of the prognostic factors may be made by either ultrasound (US) or stereotactically guided needle biopsy. Approximately 2000 stereotactic tables are installed at various medical centers throughout the United States and a significant number in other countries where breast cancer is common. Many surgeons and interventional radiologists are trained in the use of this technology for diagnostic purposes. Employing the same technology, these physicians may be trained to treat selected breast cancers with laser energy percutaneously. Experimental and clinical reports to-date indicate the technique to be safe. High-resolution imaging modalities including grayscale and color Doppler US, magnetic resonance imaging, mammography and needle biopsy, when necessary, will confirm the tumor kill. Newer imaging modalities such as magnetic resonance spectroscopy may also provide additional confirmation for total tumor ablation.

APA, Harvard, Vancouver, ISO, and other styles

24

Geraldes, Carlos F. G. C. "Introduction to Infrared and Raman-Based Biomedical Molecular Imaging and Comparison with Other Modalities." Molecules 25, no. 23 (November 26, 2020): 5547. http://dx.doi.org/10.3390/molecules25235547.

Full text

Abstract:

Molecular imaging has rapidly developed to answer the need of image contrast in medical diagnostic imaging to go beyond morphological information to include functional differences in imaged tissues at the cellular and molecular levels. Vibrational (infrared (IR) and Raman) imaging has rapidly emerged among the molecular imaging modalities available, due to its label-free combination of high spatial resolution with chemical specificity. This article presents the physical basis of vibrational spectroscopy and imaging, followed by illustration of their preclinical in vitro applications in body fluids and cells, ex vivo tissues and in vivo small animals and ending with a brief discussion of their clinical translation. After comparing the advantages and disadvantages of IR/Raman imaging with the other main modalities, such as magnetic resonance imaging (MRI), computed tomography (CT), positron emission tomography/single-photon emission-computed tomography (PET/SPECT), ultrasound (US) and photoacoustic imaging (PAI), the design of multimodal probes combining vibrational imaging with other modalities is discussed, illustrated by some preclinical proof-of-concept examples.

APA, Harvard, Vancouver, ISO, and other styles

25

Sun, Wuji, Yangye Jiang, Hong Yan, and Xiuqing Song. "Synthesis and Photoreaction of 2-Amino-3-cyano-4-aryl-4H-pyrans." Australian Journal of Chemistry 68, no. 2 (2015): 273. http://dx.doi.org/10.1071/ch14113.

Full text

Abstract:

A series of 2-amino-3-cyano-4-aryl-4H-pyrans (1) were synthesised by reacting malononitrile, ethyl acetoacetate, and aromatic aldehydes under ultrasound irradiation. The photochemical properties, including the photostability and photoreaction of 1, were investigated in conventional solvents. The results indicated that compounds 1 were unstable and underwent a photoreaction to the 1,3-butadienes under irradiation with UV light. A mechanism for the photoreaction is proposed and investigated using electron spin resonance spectroscopic techniques. The 1,3-butadiene structures were determined by 1H and 13C NMR spectra, high-resolution mass spectrometry, and single crystal X-ray diffraction analysis.

APA, Harvard, Vancouver, ISO, and other styles

26

Rådegran, Göran. "Limb and skeletal muscle blood flow measurements at rest and during exercise in human subjects." Proceedings of the Nutrition Society 58, no. 4 (November 1999): 887–98. http://dx.doi.org/10.1017/s0029665199001196.

Full text

Abstract:

The aim of the present review is to present techniques used for measuring blood flow in human subjects and advice as to when they may be applicable. Since blood flow is required to estimate substrate fluxes, energy turnover and metabolic rate of skeletal muscle, accurate measurements of blood flow are of extreme importance. Several techniques have therefore been developed to enable estimates to be made of the arterial inflow to, venous outflow from, or local blood flow within the muscle. Regional measurements have been performed using electromagnetic flow meters, plethysmography, indicator methods (e.g. thermodilution and indo-cyanine green dye infusion), ultrasound Doppler, and magnetic resonance velocity imaging. Local estimates have been made using 133Xe clearance, microdialysis, near i.r. spectroscopy, positron emission tomography and laser Doppler. In principle, the aim of the study, the type of interventions and the limitations of each technique determine which method may be most appropriate. Ultrasound Doppler and continuous indo-cyanine green dye infusion gives the most accurate limb blood flow measurements at rest. Moreover, the ultrasound Doppler is unique, as it does not demand a steady-state, and because its high temporal resolution allows detection of normal physiological variations as well as continuous measurements during transitional states such as at onset of and in recovery from exercise. During steady-state exercise thermodilution can be used in addition to indo-cyanine green dye infusion and ultrasound Doppler, where the latter is restricted to exercise modes with a fixed vessel position. Magnetic resonance velocity imaging may in addition be used to determine blood flow within deep single vessels. Positron emission tomography seems to be the most promising tool for local skeletal muscle blood-flow measurements in relation to metabolic activity, although the mode and intensity of exercise will be restricted by the apparatus design.

APA, Harvard, Vancouver, ISO, and other styles

27

Beard, Paul. "Biomedical photoacoustic imaging." Interface Focus 1, no. 4 (June 22, 2011): 602–31. http://dx.doi.org/10.1098/rsfs.2011.0028.

Full text

Abstract:

Photoacoustic (PA) imaging, also called optoacoustic imaging, is a new biomedical imaging modality based on the use of laser-generated ultrasound that has emerged over the last decade. It is a hybrid modality, combining the high-contrast and spectroscopic-based specificity of optical imaging with the high spatial resolution of ultrasound imaging. In essence, a PA image can be regarded as an ultrasound image in which the contrast depends not on the mechanical and elastic properties of the tissue, but its optical properties, specifically optical absorption. As a consequence, it offers greater specificity than conventional ultrasound imaging with the ability to detect haemoglobin, lipids, water and other light-absorbing chomophores, but with greater penetration depth than purely optical imaging modalities that rely on ballistic photons. As well as visualizing anatomical structures such as the microvasculature, it can also provide functional information in the form of blood oxygenation, blood flow and temperature. All of this can be achieved over a wide range of length scales from micrometres to centimetres with scalable spatial resolution. These attributes lend PA imaging to a wide variety of applications in clinical medicine, preclinical research and basic biology for studying cancer, cardiovascular disease, abnormalities of the microcirculation and other conditions. With the emergence of a variety of truly compelling in vivo images obtained by a number of groups around the world in the last 2–3 years, the technique has come of age and the promise of PA imaging is now beginning to be realized. Recent highlights include the demonstration of whole-body small-animal imaging, the first demonstrations of molecular imaging, the introduction of new microscopy modes and the first steps towards clinical breast imaging being taken as well as a myriad of in vivo preclinical imaging studies. In this article, the underlying physical principles of the technique, its practical implementation, and a range of clinical and preclinical applications are reviewed.

APA, Harvard, Vancouver, ISO, and other styles

28

Calderari, Sophie, Nathalie Daniel, Eve Mourier, Christophe Richard, Michele Dahirel, Franck Lager, Carmen Marchiol, et al. "Metabolomic differences in blastocoel and uterine fluids collected in vivo by ultrasound biomicroscopy on rabbit embryos†." Biology of Reproduction 104, no. 4 (January 18, 2021): 794–805. http://dx.doi.org/10.1093/biolre/ioab005.

Full text

Abstract:

Abstract The success of embryo development and implantation depends in part on the environment in which the embryo evolves. However, the composition of the uterine fluid surrounding the embryo in the peri-implantation period remains poorly studied. In this work, we aimed to develop a new strategy to visualize, collect, and analyze both blastocoelic liquid and juxta-embryonic uterine fluid from in vivo peri-implantation rabbit embryos. Using high-resolution ultrasound biomicroscopy, embryos were observed as fluid-filled anechoic vesicles, some of which were surrounded by a thin layer of uterine fluid. Ultrasound-guided puncture and aspiration of both the blastocoelic fluid contained in the embryo and the uterine fluid in the vicinity of the embryo were performed. Using nuclear magnetic resonance spectroscopy, altogether 24 metabolites were identified and quantified, of which 21 were detected in both fluids with a higher concentration in the uterus compared to the blastocoel. In contrast, pyruvate was detected at a higher concentration in blastocoelic compared to uterine fluid. Two acidic amino acids, glutamate and aspartate, were not detected in uterine fluid in contrast to blastocoelic fluid, suggesting a local regulation of uterine fluid composition. To our knowledge, this is the first report of simultaneous analysis of blastocoelic and uterine fluids collected in vivo at the time of implantation in mammals, shedding new insight for understanding the relationship between the embryo and its local environment at this critical period of development.

APA, Harvard, Vancouver, ISO, and other styles

29

Bacci, A. "Appunti dal Congresso ASNR di Vancouver Risonanza Magnetica a 3 Tesla." Rivista di Neuroradiologia 15, no. 6 (December 2002): 779–85. http://dx.doi.org/10.1177/197140090201500619.

Full text

Abstract:

The theme of this year's 40th Congress of the American Society of Neuroradiology was 3 Tesla magnetic resonance. For many years, research into the use of magnetic resonance systems with 3 T magnets mainly focused on spectroscopy and functional magnetic resonance. More recent studies also used 3 T magnets for MR diagnosis, trying to optimize sequences for both anatomic imaging and for MR angiography and diffusion on the basis of protocols currently adopted with 1.5 T magnets1–3. The use of higher magnetic fields improves the signal/noise ratio and the chemical-shift sensitivity thereby enhancing spatial resolution (supported by the higher signal/noise ratio) and increasing the reliability of spectroscopy and functional MR imaging. The major technical problems encountered with 3 T systems are the increased number of artefacts due to magnetic sensitivity and chemical shift, the increase in tissue heating potential and the longer T1 longitudinal relaxation times. The main advantages of high magnetic field resonances are the higher signal/noise ratio, greater spectra dispersion, improved image resolution, faster acquisition times and greater sensitivity to differences in magnetic susceptibility. The drawbacks include a lower signal/noise ratio in relation to artefacts caused by magnetic susceptibility, longer T1 relaxation times, shorter T2 and T2* relaxation times, convergent tissue relaxation times, increased absorption of RF energy and a more inhomogeneous B1 signal. The advantages and limitations of higher magnetic field magnets have already been encountered at each stage in the development of MR technology. Once again, the best strategies need to be devised for the use of these new systems. Briefly, the increased signal produced by high field magnets (3 T) offers different advantages. In conventional diagnosis, the spatial resolution of the image is improved or acquisition times shortened, or when contrast is poor with current techniques as in functional MR or spectroscopy. Even the increase in artefacts due to magnetic susceptibility and chemical shift can be exploited advantageously. For example, the enhanced magnetic susceptibility produces a greater loss of signal intensity in sequences with gadolinium bolus perfusion, thereby improving assessment of brain haemodynamics and tissue vitality for a rational selection of candidates for stroke therapy and surgery. Studies were presented from different stroke centres in the United States using protocols comprising sequences for conventional anatomical investigation, weighted diffusion sequences, MR angiography and bolus perfusion. Image quality was equivalent or superior to that obtained with 1.5 T systems, especially angiographic sequences which were improved and faster with easier identification of the occluded branch. It was also demonstrated that the examination can be performed while the patient is receiving an infusion of thrombolytic drugs with real time monitoring of the pharmaceutical effect on the thrombosis. A group of researchers then presented their findings studying patients with an 8T MR system23–25. Exposure to such a high magnetic field was well tolerated and the study focused on evaluation of the small cerebral vessels exploiting sensitivity differences in blood oxygenation as deoxyhaemoglobin is paramagnetic and the effected of magnetic susceptibility exaggerated by such a high field. Using inhomogeneous local fields with gradient-echo images together with the signal/noise ratio of an 8 T system, minute cerebral vessels with a diameter of around 200 micron could be visualized. What emerged from the Congress presentations was that we can no longer be satisfied with the MR systems in use today when examinations which are currently long and cumbersome can be carried out more quickly, often with real time results and much shorter processing times. The impression was that the 1.5 T MR systems most of us use will soon be as obsolete as the 0.5 T systems and neuroradiologists' work will be increasingly shifted from morphological investigation to functional analysis, entailing new expertise. My only concern is the exposure of patients to such high magnetic fields, fearing the biological effects, especially when follow-up examinations have to be repeated. I hope that patients' welfare will not be disregarded in the search for ever greater morphological detail and that the new systems will be used when their true worth is of real benefit.

APA, Harvard, Vancouver, ISO, and other styles

30

Hlinomaz, Ota, Ladislav Groch, Jan Sitar, Michal Rezek, Jiří Seménka, Martin Novák, and Nikolay Penkov. "New Imaging Methods of Coronary Arteries in Acute Coronary Syndromes." Journal Of Cardiovascular Emergencies 1, no. 2 (December 1, 2015): 56–64. http://dx.doi.org/10.1515/jce-2015-0008.

Full text

Abstract:

Abstract Coronary angiography is still the most widely used method for the assessment of lumen of coronary arteries and for diagnosis and treatment of coronary artery disease. New imaging modalities of coronary arteries play an increasing role in interventional cardiology. Intravascular ultrasound (IVUS) is the oldest technology, however due to its high tissue penetration remains very important for imaging of left main coronary artery and saphenous vein grafts. IVUS was used in many clinical trials and clinical experience with it is huge. Optical coherence tomography (OCT) is a new, very fast developing method. It has ten times higher axial resolution than IVUS. It gives us the opportunity to assess the inner structures of coronary artery wall, to evaluate the characteristics of atherosclerotic plaques, quality of stent implantation and its healing. It helps us to find the culprit lesion of acute coronary syndrome in some cases, to diagnose the cause of stent thrombosis, and to evaluate stent apposition which has a direct relation to prognosis. We use it to perform complex percutaneous coronary interventions and after heart transplantation to diagnose the vascular graft disease. We strongly believe that OCT is important for the assessment of plaque instability and patient´s prognosis. Near infrared spectroscopy combined with IVUS can distinguish fibrous from lipid core plaques. Lipid core burden index is in relation to a risk of periprocedural myocardial infarction and to prognosis. It is the only method which can sufficiently detect the amount of lipids in coronary wall.

APA, Harvard, Vancouver, ISO, and other styles

31

Hart, Corey R., Gwenael Layec, Joel D. Trinity, Yann Le Fur, Jayson R. Gifford, Heather L. Clifton, and Russell S. Richardson. "Oxygen availability and skeletal muscle oxidative capacity in patients with peripheral artery disease: implications from in vivo and in vitro assessments." American Journal of Physiology-Heart and Circulatory Physiology 315, no. 4 (October 1, 2018): H897—H909. http://dx.doi.org/10.1152/ajpheart.00641.2017.

Full text

Abstract:

Evidence suggests that the peak skeletal muscle mitochondrial ATP synthesis rate ( Vmax) in patients with peripheral artery disease (PAD) may be attenuated due to disease-related impairments in O2 supply. However, in vitro assessments suggest intrinsic deficits in mitochondrial respiration despite ample O2 availability. To address this conundrum, Doppler ultrasound, near-infrared spectroscopy, phosphorus magnetic resonance spectroscopy, and high-resolution respirometry were combined to assess convective O2 delivery, tissue oxygenation, Vmax, and skeletal muscle mitochondrial capacity (complex I + II, state 3 respiration), respectively, in the gastrocnemius muscle of 10 patients with early stage PAD and 11 physical activity-matched healthy control (HC) subjects. All participants were studied in free-flow control conditions (FF) and with reactive hyperemia (RH) induced by a period of brief ischemia during the last 30 s of submaximal plantar flexion exercise. Patients with PAD repeated the FF and RH trials under hyperoxic conditions (FF + 100% O2 and RH + 100% O2). Compared with HC subjects, patients with PAD exhibited attenuated O2 delivery at the same absolute work rate and attenuated tissue reoxygenation and Vmax after relative intensity-matched exercise. Compared with the FF condition, only RH + 100% O2 significantly increased convective O2 delivery (~44%), tissue reoxygenation (~54%), and Vmax (~60%) in patients with PAD ( P < 0.05), such that Vmax was now not different from HC subjects. Furthermore, there was no evidence of an intrinsic mitochondrial deficit in PAD, as assessed in vitro with adequate O2. Thus, in combination, this comprehensive in vivo and in vitro investigation implicates O2 supply as the predominant factor limiting mitochondrial oxidative capacity in early stage PAD. NEW & NOTEWORTHY Currently, there is little accord as to the role of O2 availability and mitochondrial function in the skeletal muscle dysfunction associated with peripheral artery disease. This is the first study to comprehensively use both in vivo and in vitro approaches to document that the skeletal muscle dysfunction associated with early stage peripheral artery disease is predominantly a consequence of limited O2 supply and not the impact of an intrinsic mitochondrial defect in this pathology.

APA, Harvard, Vancouver, ISO, and other styles

32

Laschke, Matthias W., Christina Körbel, Jeannette Rudzitis-Auth, Isabella Gashaw, Michael Reinhardt, Peter Hauff, Thomas M. Zollner, and Michael D. Menger. "High-Resolution Ultrasound Imaging." American Journal of Pathology 176, no. 2 (February 2010): 585–93. http://dx.doi.org/10.2353/ajpath.2010.090617.

Full text

APA, Harvard, Vancouver, ISO, and other styles

33

Kerr, Lucy. "High-Resolution Thyroid Ultrasound." Ultrasound Quarterly 12, no. 1 (1994): 21–44. http://dx.doi.org/10.1097/00013644-199412010-00002.

Full text

APA, Harvard, Vancouver, ISO, and other styles

34

Tittmann, Bernhard R. "High‐resolution ultrasound: A survey." Journal of the Acoustical Society of America 119, no. 5 (May 2006): 3329. http://dx.doi.org/10.1121/1.4786380.

Full text

APA, Harvard, Vancouver, ISO, and other styles

35

Garibaldi, F. "High resolution hypernuclear spectroscopy." European Physical Journal A 24, S1 (February 2005): 91–94. http://dx.doi.org/10.1140/epjad/s2005-05-016-8.

Full text

APA, Harvard, Vancouver, ISO, and other styles

36

Buckin, Vitaly. "High-resolution ultrasonic spectroscopy." Journal of Sensors and Sensor Systems 7, no. 1 (March 29, 2018): 207–17. http://dx.doi.org/10.5194/jsss-7-207-2018.

Full text

Abstract:

Abstract. High-resolution ultrasonic spectroscopy (HR-US) is an analytical technique for direct and non-destructive monitoring of molecular and micro-structural transformations in liquids and semi-solid materials. It is based on precision measurements of ultrasonic velocity and attenuation in analysed samples. The application areas of HR-US in research, product development, and quality and process control include analysis of conformational transitions of polymers, ligand binding, molecular self-assembly and aggregation, crystallisation, gelation, characterisation of phase transitions and phase diagrams, and monitoring of chemical and biochemical reactions. The technique does not require optical markers or optical transparency. The HR-US measurements can be performed in small sample volumes (down to droplet size), over broad temperature range, at ambient and elevated pressures, and in various measuring regimes such as automatic temperature ramps, titrations and measurements in flow.

APA, Harvard, Vancouver, ISO, and other styles

37

Diehl, Bernd W. K. "High resolution NMR spectroscopy." European Journal of Lipid Science and Technology 103, no. 12 (December 2001): 830–34. http://dx.doi.org/10.1002/1438-9312(200112)103:12<830::aid-ejlt830>3.0.co;2-8.

Full text

APA, Harvard, Vancouver, ISO, and other styles

38

Brünken, S., and S. Schlemmer. "High Resolution Laboratory Spectroscopy." EAS Publications Series 75-76 (2015): 295–307. http://dx.doi.org/10.1051/eas/1575061.

Full text

APA, Harvard, Vancouver, ISO, and other styles

39

Stasyuk, Natalia Ye, Galina Z. Gayda, Roman Ja Serkiz, and Mykhailo V. Gonchar. "Cell Imaging with Fluorescent Bi-Metallic Nanoparticles." JOURNAL OF ADVANCES IN CHEMISTRY 11, no. 4 (March 9, 2015): 3499–511. http://dx.doi.org/10.24297/jac.v11i4.6694.

Full text

Abstract:

Last decades various imaging techniques have been applied in biological and biomedical research, such as magnetic resonance imaging, different types of tomography, fluorescence/bioluminescence, ultrasound, as well as multimodality approaches. Fluorescence imaging, especially in combination with nanoscale materials, is a very prospective tool for experiments in vivo and clinical applications due to its high temporal and spatial resolutions. Fluorescent nanoparticles (NPs), having ability to interact with biomolecules both on the surface of and inside the cells, may revolutionize the cell imaging approaches for diagnostics and therapy. In our investigation we report about new method of cell imaging with fluorescent bi-metallic NPs synthesized by chemical reduction of the relevant ions. As the model of living organism, the cells of yeast Hansenula polymorpha were used. All NPs in minimal concentration (up to 0.05 mM) was proved to be non-toxic for yeast cells. The NPs and NPs-modified cells were characterized with the methods of UV-VIS spectroscopy, scanning electron microscopy, atom force microscopy, transmission electron microscopy and fluorescence microscopy. The bimetallic NPs, possessing the stable fluorescence in solution and inside the cells, allow to observe the phenomenon of NPs transferring from parental to daughter cells through at least three generations followed by releasing from the modified cells. The fluorescent NPs synthesized being small, non-toxic and fluorescent was shown to be perspective tool for cell imaging.

APA, Harvard, Vancouver, ISO, and other styles

40

Starck, Göran, Barbro Vkhoff-Baaz, Maria Ljungberg, Kristina Malmgren, Eva Forssell-Aronsson, Lars Jönsson, and Sven Ekholm. "Anterior to posterior hippocampal MRS metabolite difference is mainly a partial volume effect." Acta Radiologica 51, no. 3 (April 2010): 351–59. http://dx.doi.org/10.3109/02841850903540401.

Full text

Abstract:

Background: The concentration of N-acetylaspartate (NAA) in hippocampus, as measured with magnetic resonance spectroscopy (MRS), and the ratio of NAA/(choline (Cho) + creatine (Cr)) are valuable tools in the lateralization of temporal lobe epilepsy (TLE). MRS of hippocampus is also increasingly used to study certain psychiatric and degenerative diseases. However, the reliability of such measurements of hippocampus has been questioned. Purpose: To re-evaluate MRS imaging data from prior control subjects with regard to variation of metabolite concentrations in hippocampus from anterior to posterior and the partial volume ®contribution to the measurements from adjacent tissue. Material and Methods: Twelve healthy subjects, mean age 33 years, were studied with MRS imaging. The measurement volume was angled along the temporal horns and metabolite concentration images were reconstructed at the MR system. Regions of interest (ROIs) in the anterior, medial, and posterior parts of both hippocampi were evaluated. Signal normalization to the total MRS signal from all ROIs permitted pooling of individual data with different and unknown signal scaling. One subject was re-examined with a high resolution three-dimensional (3D) volume of the brain for evaluation of partial volumes in the MRS examination. Results: Overall, there were significantly lower concentrations of NAA in the anterior parts, and of (Cho+Cr) in the posterior parts, while the NAA/(Cho+Cr) ratio in the posterior parts of the mesial temporal lobes was significantly higher. Hippocampus accounted for one-half, one-third, and one-quarter of the anterior, middle, and posterior ROIs, respectively. The NAA/(Cho+Cr) ratio thus showed a reverse relationship to the relative volume of hippocampal tissue within the ROI. Conclusion: Metabolite concentrations in the mesial temporal lobe obtained with MRS imaging represent the mean value of hippocampus and a considerable amount of adjacent tissue. To assess the hippocampus alone, an actual voxel well below 1 cm3 and a sub-centimeter slice thickness are required.

APA, Harvard, Vancouver, ISO, and other styles

41

Srivastava, P. K. "High Resolution Ultrasound of Brachial Plexus." Ultrasound in Medicine & Biology 43 (2017): S242. http://dx.doi.org/10.1016/j.ultrasmedbio.2017.08.1848.

Full text

APA, Harvard, Vancouver, ISO, and other styles

42

Srivastava, P. K. "High Resolution Ultrasound of Paediatric Neck." Ultrasound in Medicine & Biology 43 (2017): S175. http://dx.doi.org/10.1016/j.ultrasmedbio.2017.08.1588.

Full text

APA, Harvard, Vancouver, ISO, and other styles

43

GROPPER, CHARLES A., MATTHEW J. STILLER, JEROME L. SHUPACK, JACK DRILLER, MARY RORKE, and FREDERIC LIZZI. "DIAGNOSTIC HIGH-RESOLUTION ULTRASOUND IN DERMATOLOGY." International Journal of Dermatology 32, no. 4 (April 1993): 243–50. http://dx.doi.org/10.1111/j.1365-4362.1993.tb04261.x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

44

Wang, Lihong V. "Ultrasound‐aided high‐resolution biophotonic imaging." Journal of the Acoustical Society of America 114, no. 4 (October 2003): 2377. http://dx.doi.org/10.1121/1.4777486.

Full text

APA, Harvard, Vancouver, ISO, and other styles

45

Freitag, M., K. Hoffmann, S. el Gammal, and P. Altmeyer. "High resolution ultrasound of skin tumours." Melanoma Research 6, SUPPLEMENT 1 (September 1996): S29. http://dx.doi.org/10.1097/00008390-199609001-00073.

Full text

APA, Harvard, Vancouver, ISO, and other styles

46

Cronau, M., and H. Gerhards. "High resolution ultrasound in equine ophthalmology." Pferdeheilkunde Equine Medicine 20, no. 4 (2004): 321–26. http://dx.doi.org/10.21836/pem20040402.

Full text

APA, Harvard, Vancouver, ISO, and other styles

47

Whittle, Carolina, Javiera Aguirre, Veronica Catalán, Ximena Fajre, and Fabiola Vargas. "Subungual Exostosis: High-Resolution Ultrasound Findings." Journal of Diagnostic Medical Sonography 35, no. 5 (March 10, 2019): 387–90. http://dx.doi.org/10.1177/8756479319836943.

Full text

Abstract:

Subungual exostosis is a rare solitary benign osteocartilaginous tumor that arises from the tuft of the distal phalanx beneath the nail. Because of its multiple clinical presentations, it is commonly underdiagnosed, resulting in delayed diagnosis and inadequate treatment. This report provides results from a 6-year retrospective study. All patients with a sonographic diagnosis of subungual exostosis confirmed surgically were selected. The data came from a series of 19 patient cases. Only 15.7% were clinically suspected. The median age was 21 years, and 63% were females. The sonographic findings were nail dystrophy, distal onycholysis, abnormal nail incurvation, subungual space enlargement, and the presence of hyperechogenic subungual image with acoustic shadowing that continued until the phalanx surface. Sonography provides an excellent diagnostic method for subungual exostosis, with findings that are pathognomonic.

APA, Harvard, Vancouver, ISO, and other styles

48

Wang, Lihong V. "Ultrasound‐aided high‐resolution biophotonic imaging." Journal of the Acoustical Society of America 116, no. 4 (October 2004): 2616. http://dx.doi.org/10.1121/1.4808624.

Full text

APA, Harvard, Vancouver, ISO, and other styles

49

Nikoonahad, M., and F. Li. "High-resolution ultrasound transverse flow measurement." Electronics Letters 24, no. 4 (1988): 205. http://dx.doi.org/10.1049/el:19880137.

Full text

APA, Harvard, Vancouver, ISO, and other styles

50

Coraci, Daniele, Ilaria Paolasso, Pietro Emiliano Doneddu, Valter Santilli, and Luca Padua. "High-resolution ultrasound may depict pseudomeningocele." Neurological Sciences 37, no. 8 (March 15, 2016): 1369–72. http://dx.doi.org/10.1007/s10072-016-2545-6.

Full text

APA, Harvard, Vancouver, ISO, and other styles

We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!