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1.
Artículo en Inglés | MEDLINE | ID: mdl-38082913

RESUMEN

Computer-aided diagnostic methods, such as automatic and precise liver tumor detection, have a significant impact on healthcare. In recent years, deep learning-based liver tumor detection methods in multi-phase computed tomography (CT) images have achieved noticeable performance. Deep learning frameworks require a substantial amount of annotated training data but obtaining enough training data with high quality annotations is a major issue in medical imaging. Additionally, deep learning frameworks experience domain shift problems when they are trained using one dataset (source domain) and applied to new test data (target domain). To address the lack of training data and domain shift issues in multiphase CT images, here, we present an adversarial learning-based strategy to mitigate the domain gap across different phases of multiphase CT scans. We introduce to use Fourier phase component of CT images in order to improve the semantic information and more reliably identify the tumor tissues. Our approach eliminates the requirement for distinct annotations for each phase of CT scans. The experiment results show that our proposed method performs noticeably better than conventional training and other methods.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Neoplasias Hepáticas , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Neoplasias Hepáticas/diagnóstico por imagen
2.
Children (Basel) ; 10(5)2023 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-37238422

RESUMEN

BACKGROUND: The number of children infected with novel coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has increased during the outbreak of the Omicron strain. Hyperferritinemia has been reported in severe cases of COVID-19, and in children or neonates with multisystem inflammatory syndrome (MIS). Hyperferritinemia is considered to be one of the signs of MIS, but thus far, there have been few summarized reports on it. We retrospectively analyzed four infants less than 3 months of age with SARS-CoV-2 infections treated in our institution during the outbreak of the Omicron strain. RESULTS: most patients were in good condition, but hyperferritinemia was observed in all of four cases. CONCLUSIONS: Hyperferritinemia can be observed in infantile COVID-19 patients even with mild symptoms. It is necessary to carefully monitor their clinical course and monitor the patients.

3.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 1536-1539, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-36085648

RESUMEN

Automatic and efficient liver tumor detection in multi-phase CT images is essential in computer-aided diagnosis of liver tumors. Nowadays, deep learning has been widely used in medical applications. Normally, deep learning-based AI systems need a large quantity of training data, but in the medical field, acquiring sufficient training data with high-quality annotations is a significant challenge. To solve the lack of training data issue, domain adaptation-based methods have recently been developed as a technique to bridge the domain gap across datasets with different feature characteristics and data distributions. This paper presents a domain adaptation-based method for detecting liver tumors in multi-phase CT images. We adopt knowledge for model learning from PV phase images to ART and NC phase images. Clinical Relevance- To minimize the domain gap we employ an adversarial learning scheme with the maximum square loss for mid-level output feature maps using an anchorless detector. Experiments show that our proposed method performs much better for various CT-phase images than normal training.


Asunto(s)
Aclimatación , Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Radiofármacos , Tomografía Computarizada por Rayos X
4.
Beilstein J Org Chem ; 18: 152-158, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35140816

RESUMEN

We report the high-speed C-H chlorination of ethylene carbonate, which gives chloroethylene carbonate, a precursor to vinylene carbonate. A novel photoflow setup designed for a gas-liquid biphasic reaction turned out to be useful for the direct use of chlorine gas. The setup employed sloped channels so as to make the liquid phase thinner, ensuring a high surface-to-volume ratio. When ethylene carbonate was introduced to the reactor, the residence time was measured to be 15 or 30 s, depending on the slope of the reactor set at 15 or 5°, respectively. Such short time of exposition sufficed the photo C-H chlorination. The partial irradiation of the flow channels also sufficed for the C-H chlorination, which is consistent with the requirement of photoirradiation for the purpose of radical initiation. Near-complete selectivity for single chlorination required the low conversion of ethylene carbonate such as 9%, which was controlled by limited introduction of chlorine gas. At a higher conversion of ethylene carbonate such as 61%, the selectivity for monochlorinated ethylene carbonate over dichlorinated ethylene carbonate was 86%. We found that the substrate contamination with water negatively influenced the performance of the C-H chlorination.

7.
Dalton Trans ; 49(12): 3692-3699, 2020 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-32091516

RESUMEN

Flexible porous materials have great potential for adsorption/separation of small molecules. In this study, a highly CO2-selective two-dimensional (2D) layered metal-organic framework (MOF) showing gate-type adsorption properties was synthesized and fully characterized by single-crystal X-ray diffraction (XRD), in situ powder XRD, thermogravimetric analysis, inductively coupled plasma atomic emission spectroscopy, and gas adsorption/separation analyses. The MOF named ELM-13 is a 2D layered material functionalized with (trifluoromethyl)trifluoroborate to control interlayer interactions and exhibits dynamic guest accommodation/removal properties. In a gas adsorption study, the MOF showed no adsorption at low pressure followed by abrupt uptake and sudden desorption at a pressure lower than that of adsorption, i.e., gate adsorption, in the N2, O2, Ar, NO, and CO2 isotherms at the boiling/sublimation temperature of each gas. The structure of the MOF in the CO2 adsorption was influenced by both the amount adsorbed and the adsorption process. High-pressure adsorption experiments at 273 K indicated that, out of N2, O2, Ar, and CO2, only CO2 was adsorbed on the MOF below 900 kPa. The CO2 selectivity from an equimolar CO2/N2 mixture with a total gas pressure of 1 MPa at 273 K was experimentally evaluated and compared with the CO2 selectivities of other selected porous materials theoretically, suggesting that ELM-13 is a good candidate for CO2 separation.

8.
Langmuir ; 35(40): 13003-13010, 2019 10 08.
Artículo en Inglés | MEDLINE | ID: mdl-31510745

RESUMEN

Cooperativity of motor proteins is essential for intracellular transport. Although their motion is unidirectional, they often cause bidirectional movement by different types of motors as seen in organelles. However, in vitro assessments of such cellular functions are still inadequate owing to the experimental limitations in precisely patterning multiple motors. Here, we present an approach to immobilize two motor proteins, kinesin-1 and dynein, using the aqueous two-phase system (ATPS) made of poly(ethylene glycol) and dextran polymers. The negligible influence of polymer solutions on the attachment and velocity of motor proteins ensures the compatibility of using ATPS as the patterning technique. The selective fixation of kinesin and dynein was assessed using polarity-marked microtubules (PMMTs). Our experimental results show that on a patterned kinesin surface, 72% of PMMTs display minus-end leading motility, while on a dynein surface, 79% of PMMTs display plus-end leading motility. This work offers a universal and biocompatible method to pattern motor proteins of different classes at the nanoscale, providing a new route to study different cellular functions performed by molecular motors such as the formation of mitotic spindles.


Asunto(s)
Dextranos/química , Dineínas/metabolismo , Cinesinas/metabolismo , Microtúbulos/metabolismo , Polietilenglicoles/química , Animales , Bioensayo , Dictyostelium , Humanos , Movimiento (Física) , Porcinos
9.
Chem Senses ; 39(9): 781-6, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25305761

RESUMEN

The excessive intake of dietary salt is a global issue in health. Attempts have been made to address this issue, including the development of salt substitutes. Yet, none of these substances are currently in wide use, because of their weak saltiness. The purpose of this study was to assess the effects of sodium aspartate (Asp-Na) on salty taste perception using the bullfrog glossopharyngeal nerve response and human sensory tests. When added to the mixture of NaCl and KCl, Asp-Na significantly enhanced the glossopharyngeal nerve response to the mixture by 1.6-fold compared to control. Asp-Na did not enhance the response to NaCl, nor did Asp-Na enhance the response to sour, bitter, or umami stimuli. The optimal concentration for Asp-Na to enhance the salt mixture was 1.7mM. The largest enhancement was induced when NaCl and KCl were mixed at equimolar concentrations. Asp-Na significantly suppressed the glossopharyngeal nerve response to quinine hydrochloride, which suggests that bitterness of KCl is suppressed by Asp-Na. The salty taste enhancing effect of Asp-Na was also confirmed with human sensory tests. The present results suggested that the mixture of NaCl and KCl containing Asp-Na can be used as a salt substitute. In addition to demonstrating that Asp-Na enhanced salt taste responses in an experimental animal and human, our findings provide clues to identify the elusive salty taste receptors.


Asunto(s)
Ácido Aspártico/farmacología , Nervio Glosofaríngeo/efectos de los fármacos , Rana catesbeiana/fisiología , Cloruro de Sodio Dietético/metabolismo , Percepción del Gusto/efectos de los fármacos , Adulto , Animales , Ácido Aspártico/metabolismo , Femenino , Nervio Glosofaríngeo/fisiología , Humanos , Masculino , Gusto/efectos de los fármacos
10.
Inorg Chem ; 49(20): 9247-52, 2010 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-20843060

RESUMEN

A two-dimensional flexible porous coordination polymer (2D-PCP) that shows expansion/shrinkage structural transformation accompanied by molecular accommodation was synthesized by control of dimensionality in zero-dimensional and one-dimensional PCPs: The dynamic structural transformation cooperatively proceeds in the solid state with a drastic molecular rearrangement. Kinetics of the structural transformation was investigated.

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