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1.
Membranes (Basel) ; 13(1)2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36676922

RESUMO

Recently, polymer electrolytes have been developed for high-performance and eco-friendly fuel cells. Among the candidates, eggshell membrane (ESM) has been promising because of its abundance to assemble various energy devices with low cost and its absorption ability of organic materials. In this work, we investigated fuel cells that included ESM-absorbing xanthene-, triphenylmethane-, and azo-type tar dye, which contained abundant hydrophilic groups, as polymer electrolytes. We found out two points: (1) that the fuel cells that included ESM-absorbing xanthene-type dye generated the highest I-V performance, and (2) the basic molecular structures of the tar dyes determined the correlation of the maximum power and proton conductivities.

2.
ACS Omega ; 7(15): 12637-12642, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35474842

RESUMO

Polymer electrolyte membrane fuel cells have recently attracted considerable attention as sustainable and eco-friendly electricity generation devices from the viewpoint of carbon neutrality. This study focuses on new discoveries related to the application of eggshell membranes to polymer electrolytes in the development of cheaper, more eco-friendly fuel cells. We observed the electricity generation of the fuel cells using an eggshell membrane as a proton-conductive material and a general carbonic acid aqueous solution. This new fuel cell will contribute to the continued improvement of available fuel cells at lower costs.

3.
Abdom Radiol (NY) ; 47(6): 1929-1938, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35226124

RESUMO

PURPOSE: This study aimed to investigate the characteristics of magnetic resonance imaging (MRI) findings in pure prostatic ductal adenocarcinoma. METHODS: From January 2009 to February 2020, seven patients who were diagnosed with pure prostatic ductal adenocarcinoma and had a referable preoperative MRI scan were included in the study. We evaluated the following MRI findings for each tumor: size, location, presence of multi-cystic component, and apparent diffusion coefficient (ADC) value. RESULTS: The median maximum diameter of the tumors was 22 mm (range 19-70 mm). Regarding transverse distribution, five tumors were located in the periurethral area and two were located peripherally apart from the urethra. Two of the seven tumors had cystic components. The median ADC value of the tumors was 0.754 × 10-3 mm2/s (range 0.570-0.963 × 10-3 mm2/s). Based on the transverse distribution and components of the tumors on MRI, ductal adenocarcinomas were classified into three types: type I as a non-cystic tumor located peripherally apart from the urethra (29%, two cases); type II as a non-cystic tumor located in the periurethral area (43%, three cases); and type III as a tumor with a multi-cystic component (29%, two cases). CONCLUSION: The non-cystic mass with periurethral distribution (type II) and multi-cystic mass (type III) may be characteristic features that differentiate pure ductal adenocarcinoma from ordinary acinar adenocarcinoma on MRI.


Assuntos
Carcinoma de Células Acinares , Neoplasias da Próstata , Carcinoma de Células Acinares/patologia , Imagem de Difusão por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Neoplasias da Próstata/patologia
4.
Chemistry ; 26(3): 735-744, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31599004

RESUMO

The first examples of porous molecular crystals that are assembled through Au⋅⋅⋅Au interactions of gold complex 1 are here reported along with their exchange properties with respect to their guest components. Single-crystal X-ray diffraction (XRD) analyses indicate that the crystal structure of 1/CH2 Cl2 ⋅pentane is based on cyclic hexamers of 1, which are formed through six Au⋅⋅⋅Au interactions. The packing of these cyclic hexamers affords a porous architecture, in which the one-dimensional channel segment contains CH2 Cl2 and pentane as guests. These guests can be exchanged through operationally simple methods under retention of the host framework of 1, which furnished 1/guest complexes with 26 different guests. A single-crystal XRD analysis of 1/eicosane, which contains the long linear alkane eicosane (n-C20 H42 ), successfully provided its accurately modeled structure within the porous material. These host-guest complexes show chromic luminescence with both blue- and redshifted emissions. Moreover, this porous organometallic material can exhibit luminescent mechanochromism through release of guests.

5.
Acta Med Okayama ; 71(2): 91-96, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28420889

RESUMO

The aim of this study was to investigate the utility of single-source dual-energy computed tomography (SS-DECT) composition analysis in characterizing different types of urinary stones and differentiating them from phleboliths. This study included 29 patients with urinary stones who were scheduled for surgery. All patients were scanned, first using single-energy computed tomography acquisition and then DECT acquisition on SS-DECT. Dual-energy data were archived to a Gemstone spectral imaging (GSI) viewer (GE Healthcare, Milwaukee, WI, USA). Hounsfield units (HU) and effective atomic numbers (Zeff) were estimated using the GSI viewer. The results of dual-energy analysis were compared with the biochemical constitution of the stones. The chemical analysis determined that the stones included 32 calcium-based, 6 cystine and 1 struvite stone. Both HU and Zeff values were helpful in differentiating calcium-based stones from cystine and struvite stones and phleboliths. The Zeff values of phleboliths were significantly higher than those for struvite and cystine stones, whereas it was difficult to distinguish phleboliths from struvite and cystine stones using the HU values. Composition analysis using SS-DECT is helpful for distinguishing urinary stone types and discriminating phleboliths from urinary stones. Zeff values may be more useful than HU values for differentiating urinary stones from phleboliths.


Assuntos
Tomografia Computadorizada por Raios X/métodos , Cálculos Urinários/química , Absorciometria de Fóton/métodos , Adulto , Idoso , Feminino , Humanos , Cálculos Renais/química , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Calcificação Vascular/diagnóstico por imagem
7.
Neuroradiology ; 55(9): 1153-60, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23821124

RESUMO

INTRODUCTION: Although self-expanding carotid stents may dilate gradually, the degrees of residual stenosis have been quantified by the NASCET criteria, which is too simple to reflect the configuration of the stented artery. We measured the volumes of the stent lumens chronologically by 3D-CT in patients after carotid artery stenting (CAS), and analyzed the correlations between the volume change and medical factors. METHODS: Fourteen patients with carotid artery stenosis were treated using self-expanding, open-cell stents. All patients underwent preoperative plaque MRI (magnetization-prepared rapid acquisition gradient-echo, MPRAGE) and chronological 3D-CT examinations of their stents immediately after their placement and 1 day, 1 week, and 1 month after the procedure. The volume of the stent lumen was measured using a 3D workstation. The correlations between stent volume and various factors including the presence of underlying diseases, plaque characteristics, and the results of the CAS procedure were analyzed. RESULTS: Stent volume gradually increased in each case and had increased by 1.04-1.55 (mean, 1.25)-fold at 1 postoperative month. The presence of underlying medical diseases, plaque length, the degree of residual stenosis immediately after CAS, and plaque calcification did not have an impact on the change in stent volume. On the other hand, the stent volume increase was significantly larger in the patients with vulnerable plaques that demonstrated high MPRAGE signal intensity (P < 0.05). CONCLUSIONS: A 3D-CT examination is useful for precisely measuring stent volume. Self-expanding stents in carotid arteries containing vulnerable plaques expand significantly more than those without such plaques in a follow-up period.


Assuntos
Angiografia/métodos , Prótese Vascular , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/cirurgia , Interpretação de Imagem Assistida por Computador/métodos , Stents , Tomografia Computadorizada por Raios X/métodos , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Feminino , Humanos , Masculino , Implantação de Prótese/métodos , Intensificação de Imagem Radiográfica/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento
8.
Cardiovasc Intervent Radiol ; 32(3): 554-7, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-18704568

RESUMO

The aim of this study is to describe the effect of transarterial embolization from the ophthalmic artery as a pretreatment for orbital exenteration. A 75-year-old Chinese man with a 7-year history of gradual increase of the left eye swelling showed a massive conjunctival tumor growing outwardly from the interpalpebral fissure and had no light perception in the left eye. Magnetic resonance imaging showed orbital invasion of the tumor around the left eyeglobe. The initial surgery for the planned orbital exenteration was discontinued after skin incision around the orbital margin due to massive hemorrhage. The patient underwent transarterial embolization with gelatin sponge (Spongel) of the feeding arteries from the left ophthalmic artery and, the next day, had orbital exenteration with well-controllable bleeding and reconstruction with free vascularized anterolateral thigh cutaneous flap transfer. Pathologically, well-differentiated squamous cell carcinoma proliferated in exophytic, papillary, and nested fashions, arising from the bulbar conjunctiva. Tumor cells were also found in the conjunctival stroma around the vessels. The sclera at the equator had a perforated site with tumor cell invasion, but no intraocular invasion was found. Hematoxylin-positive gelatin sponges were found inside the orbital vessels and large choroidal vessels. In conclusion, transarterial embolization of feeding arteries arising from the ophthalmic artery is a useful pretreatment to control bleeding at orbital exenteration for malignancy.


Assuntos
Carcinoma de Células Escamosas/terapia , Túnica Conjuntiva/irrigação sanguínea , Neoplasias da Túnica Conjuntiva/terapia , Embolização Terapêutica/métodos , Artéria Oftálmica , Idoso , Carcinoma de Células Escamosas/cirurgia , Túnica Conjuntiva/patologia , Neoplasias da Túnica Conjuntiva/cirurgia , Humanos , Imageamento por Ressonância Magnética , Masculino , Exenteração Orbitária , Retalhos Cirúrgicos
9.
Acta Med Okayama ; 62(3): 159-68, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18596832

RESUMO

With the aim of sequence optimization in susceptibility-weighted imaging (SWI), 2 image acquisition parameters (slice thickness and matrix size) and 2 image processing conditions (number of slices per minimum intensity projection (MIP) and Sliding Window) were investigated using a 1.5-T magnetic resonance imaging (MRI) system. The subjects were 12 healthy volunteers and the target region for scanning was the whole brain. Informed consent was obtained from all subjects. First, susceptibility-weighted images were acquired with various slice thicknesses from 1mm to 5mm and various matrix sizes from 256 x 256 to 512 x 512, and the images were assessed in terms of the contrast-to-noise ratio (CNR) and were also visually evaluated by three radiologists. Then, the number of slices per MIP and the usefulness of the Sliding Window were investigated. In the study of the optimal slice thickness and matrix size, the results of visual evaluation suggested that a slice thickness of 3mm and a matrix size of 448 x 448 are optimal, while the results of evaluation based on CNR were not significant. As regards the image processing conditions, the results suggested that the number of slices per MIP should be set to a minimum value of 2 and that the use of Sliding Window is effective. The present study provides useful reference data for optimizing SWI sequences.


Assuntos
Encéfalo/patologia , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Adulto , Humanos , Imageamento por Ressonância Magnética/instrumentação , Masculino , Modelos Biológicos
10.
Acta Med Okayama ; 61(5): 247-54, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17971841

RESUMO

To evaluate the ability of multidetector-row CT (MDCT) to predict a risk of hemorrhage in patients with esophageal varices, a total of 40 MDCT scans were performed in 29 patients who had been diagnosed with esophageal varices by conventional upper gastrointestinal tract endoscopy. In 11 patients, MDCT was performed both before and after endoscopic injection sclerotherapy (EIS). Endoscopically, the red color sign (RC sign) was present in 28 scans. Of the 11 patients who underwent EIS, the RC sign disappeared after EIS in 9. The MDCT scans were obtained in the arterial, portal, and equilibrial phases, and the portal phase images were used in this study. Subsequently, the extent of esophageal varices was categorized into four MDCT scores. The variceal score, the maximum short axis of the varices, and the presence of palisade vein dilatation obtained from MDCT had significant correlation with endoscopic variceal forms, and the presence and severity of RC sign, respectively (p<0.01). All cases with a maximum minor axis of more than 4 mm showed positive RC sign. MDCT was useful in the evaluation of esophageal varices for predicting a risk of hemorrhage.


Assuntos
Endoscopia Gastrointestinal/métodos , Varizes Esofágicas e Gástricas/diagnóstico por imagem , Varizes Esofágicas e Gástricas/patologia , Hemorragia Gastrointestinal/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Varizes Esofágicas e Gástricas/complicações , Feminino , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fatores de Risco , Índice de Gravidade de Doença
11.
Acta Med Okayama ; 60(4): 215-21, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16943858

RESUMO

To determine the efficacy of flow-sensitive alternating inversion recovery using half-Fourier single-shot turbo spin-echo (FAIR-HASTE) in detecting cerebral hypoperfusion in chronic carotid occlusive disease, we subjected 12 patients with various degrees of cervical internal carotid artery stenoses and/or occlusion (Stenosis group) and 24 volunteers (Normal group) to FAIR-HASTE. In addition, 10 out of 12 patients in the Stenosis group underwent dynamic susceptibility contrast-perfusion magnetic resonance imaging (DSC-pMRI) before and after revascularization in the dominantly affected side. The absolute asymmetry indexes (AIs) of both cerebral hemispheres in the Normal and Stenosis groups were compared in FAIR-HASTE. In addition, the AIs were compared with those in the Stenosis group before and after revascularization in both FAIR-HASTE and regional cerebral blood flow (rCBF), calculated with DSC-pMRI. A statistically significant difference was recognized between the AIs in the Normal and Stenosis groups (AI = 2.25 +- 1.92, 8.09 +- 4.60, respectively ; p < 0.0001). Furthermore, in the Stenosis group the AIs on both FAIR-HASTE (8.88 +- 4.93, 2.22 +- 1.79, respectively ; p = 0.0003) and rCBF (7.13 +- 3.57, 1.25 +- 1.33, respectively ; p = 0.0003) significantly decreased after revascularization. In the Stenosis group, before revascularization, signal intensity on both FAIR-HASTE and rCBF had a tendency to be lower in the dominantly affected side. FAIR-HASTE imaging was useful in the detection and evaluation of cerebral hypoperfusion in chronic occlusive carotid disease.


Assuntos
Estenose das Carótidas/patologia , Imageamento por Ressonância Magnética , Adulto , Idoso , Doença Crônica , Meios de Contraste , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade
12.
No To Shinkei ; 55(5): 419-22, 2003 May.
Artigo em Japonês | MEDLINE | ID: mdl-12833884

RESUMO

A 50-year-old woman developed discomfort of oral cavity and dysarthria. Her tongue showed a slight left-deviation and atrophy in the left side in a month. Examination with X-p, CT, and MRI showed hypoplasia of the atlas and high cervical ossification of the posterior longitudinal ligament (OPLL) from C1 to C5. Thus, combination of congenital hypoplasia of the atlas and acquired high cervical OPLL reduced a function of hypoglossal nerve, which resulted in the palsy. In a case of unilateral hypoglossal palsy, a possible lesion of foramen magnum should be considered.


Assuntos
Atlas Cervical/anormalidades , Doenças do Nervo Hipoglosso/etiologia , Ossificação do Ligamento Longitudinal Posterior/complicações , Atlas Cervical/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Ossificação do Ligamento Longitudinal Posterior/diagnóstico , Tomografia Computadorizada por Raios X
13.
Physiol Chem Phys Med NMR ; 35(2): 145-56, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-15552725

RESUMO

The purpose of this study was to evaluate clinically T1-weighted spin-echo imaging (T1-SE) and T1-weighted opposed-phase gradient-echo (T1-opposed GRE) in medical examinations for vertebral metastases using 0.2 Tesla MRI. Twenty-one patients (9 males and 12 females, 105 vertebrae) with non-neoplastic lesions were assigned to the normal group (Group N), whereas 27 patients (16 males and 11 females, 133 vertebrae) with malignant metastatic vertebral lesions were assigned to the metastatic group (Group M). Using quantitative analysis, the contrast to noise ratio (CNR) for bone marrow to muscle in the region of interest (ROI) defined by the operator were determined with both groups, whereas the CNR for lesion to bone marrow was determined with Group M. In the subjective analysis, 275 vertebrae of 27 patients in Group M were evaluated. There were significant differences in the Group M between CNR values, T1-SE and T1-opposed GRE. The evaluation by T1-SE image alone was rated as 85.0% for sensitivity, 99.3% for specificity, respectively. On the other hand, evaluation rate only by T1-opposed GRE was 98.5% for sensitivity, 82.4% for specificity, respectively. T1-opposed GRE image is an effective tool for 0.2 Tesla MRI to examine metastatic bone marrow tumors. These findings indicate the necessity of both T1-SE and T1-opposed GRE in diagnostic imaging of vertebral metastases using 0.2 Tesla MRI.


Assuntos
Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Neoplasias da Coluna Vertebral/diagnóstico , Neoplasias da Coluna Vertebral/secundário , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
No To Shinkei ; 54(1): 35-40, 2002 Jan.
Artigo em Japonês | MEDLINE | ID: mdl-11868349

RESUMO

A 58-year-old woman began to show ataxia at age 45 and dysarthria at age 56. Neurological examination revealed slurred speech, truncal ataxia, and pyramydal sign. Neither history of alcoholism nor hereditary factors were found. The level of serum ammonia was increased. Brain MRI study showed a high signal intensity in the cerebral peduncle and globus pallidus and mild cerebellar atrophy on T1-weighted image. A portal-systemic shunt due to a shunt vessel was found between the left splenic and kidney veins although she did not show any other symptoms or signs due to liver cirrhosis. Her symptoms dramatically improved by an intravenous administration of branched amino acid. The present case suggests an importance in finding a treatable cerebellar ataxia.


Assuntos
Aminoácidos de Cadeia Ramificada/uso terapêutico , Ataxia Cerebelar/tratamento farmacológico , Ataxia Cerebelar/etiologia , Encefalopatia Hepática/complicações , Feminino , Encefalopatia Hepática/tratamento farmacológico , Humanos , Pessoa de Meia-Idade
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