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1.
Rev Sci Instrum ; 81(2): 023304, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20192489

RESUMO

A multichannel time-of-flight (TOF) system was constructed to observe the ions generated from relativistic laser plasma, where the ions have polychromatic energies and multiple species. The TOF system is composed of a ten-channel scintillation detector array and an electromagnet that generates a magnetic field of 0-1.24 T. The magnet field enables us to analyze protons, deuterons, and full-stripped carbon ions to 50, 25, and 150 MeV, respectively. The system experimentally identified protons of 0.27-1.6 MeV energy and ions of a half specific charge (deuterons of 0.3-0.8 MeV and full-stripped carbons of 1.8-4.8 MeV). The measured TOF values agree well with the calculated values within the designed accuracy; +/-2.5 ns for protons and +/-5 ns for the others (d or C(6+)) on each detector channel. Comparison of ion numbers detected by a track detector (CR-39) and the TOF system enabled us to obtain the number of ions detected on each scintillation counter with less than 16% error.

2.
Opt Lett ; 27(5): 309-11, 2002 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-18007786

RESUMO

We have demonstrated femtosecond time-resolved and picosecond time-interval successive observations of a single femtosecond optical pulse propagating in air with ultrafast self-modulation such as filamentation. A quadruple femtosecond probe pulse crossing an intense propagating pulse at picosecond intervals was able to capture directly four successive images of the propagating pulse as in a movie but with femtosecond time resolution. From this observation, we can directly analyze and recognize the propagation process, which is significantly affected by pulse-energy fluctuation, and (or) atmospheric turbulence from shot to shot.

3.
Jpn J Ophthalmol ; 44(6): 691-692, 2000 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11094195

RESUMO

Purpose: Eyes with an intraocular lens (IOL) implanted that have no accommodative ability are likely to have night myopia caused by Purkinje's shift and chromatic aberration. We evaluated the changes in retinal images caused by night myopia in various IOL-implanted eyes by simulation using model eyes.Methods: A polymethylmethacrylate (PMMA) IOL, soft acrylic IOLs, and high-refractive-index silicone IOLs were prepared, and inserted into the model eye. The image plane of the model eye was determined as the line image at which a slit light of 560 nm was best focused, which was regarded as emmetropic condition under photopic vision. A slit light of 505 nm was then directed into the model eye. Its line image on the image plane was blurred, which was regarded as myopic condition under scotopic vision. Under each condition. The modulation transfer functions (MTF) were calculated and the line images were photographed.Results: The degree of reduction of MTF and blurring of the line image under the night myopic condition was in the order of PMMA

4.
Hinyokika Kiyo ; 46(4): 273-6, 2000 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-10845161

RESUMO

We report here 3 cases of papillary adenocarcinoma of the prostate. In all 3 cases, the tumors were discernible on cystourethroscopy and transurethral biopsy established the diagnosis, whereas no significant finding was found on digital rectal examination. Although androgen deprivation therapy was administered in all cases, different surgical procedures were employed according to the stage in each case. In case 1, since the papillary tumor was confined within the prostatic urethra, complete resection was accomplished by transurethral resection (TUR). In case 2, since pelvic lymph nodes metastases were found, local radiation therapy was added. In case 3, since the patient had vesical invasion of tumor total cysto-prostatectomy was performed. Papillary adenocarcinoma of the prostate originates from the prostatic duct, resulting in existence at the "central portion" of the prostate gland. Cystourethroscopy and transurethral biopsy is helpful for diagnosis of this disease, whereas rectal digital examination is useless. As a surgical procedure for the primary site, TUR may be efficient for tumors confined within the prostatic urethra, although more extensive surgery may be necessary for those with a more invasive profile.


Assuntos
Adenocarcinoma Papilar , Neoplasias da Próstata , Adenocarcinoma Papilar/patologia , Adenocarcinoma Papilar/radioterapia , Adenocarcinoma Papilar/cirurgia , Idoso , Terapia Combinada , Cistectomia , Cistoscopia , Humanos , Masculino , Prostatectomia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/cirurgia
5.
Nippon Ganka Gakkai Zasshi ; 104(5): 324-7, 2000 May.
Artigo em Japonês | MEDLINE | ID: mdl-10835886

RESUMO

PURPOSE: Eyes with an intraocular lens (IOL) implanted that have no accommodative ability are likely to have night myopia caused by Purkinje's shift and chromatic aberration. We evaluated the changes in retinal images caused by night myopia in various IOL-implanted eyes by simulation using model eyes. METHODS: A polymethylmethacrylate (PMMA) IOL, soft acrylic IOLs, and high-refractive-index silicone IOLs were prepared, and inserted into the model eye. The image plane of the model eye was determined as the line image at which a slit light of 560 nm was best focused, which was regarded as emmetropic condition under photopic vision. A slit light of 505 nm was then directed into the model eye. Its line image on the image plane was blurred, which was regarded as myopic condition under scotopic vision. Under each condition, the modulation transfer functions (MTF) were calculated and the line images were photographed. RESULTS: The degree of reduction of MTF and blurring of the line image under the night myopic condition was in the order of PMMA < soft acrylic < high refractive index silicone IOL. CONCLUSION: Eyes with a soft acrylic or high-refractive-index silicone IOL may have more intense night myopia caused by chromatic aberration.


Assuntos
Lentes Intraoculares , Miopia/etiologia , Catarata/fisiopatologia , Humanos , Modelos Biológicos , Tempo
6.
Hinyokika Kiyo ; 45(6): 435-7, 1999 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-10442289

RESUMO

We report two rare cases of urinary retention secondary to aseptic meningitis. Case I was in a 13-year-old boy admitted to the pediatric department due to aseptic meningitis. Eight days after his admission, urinary retention developed and cystometry showed atonic bladder. Case 2 was in a 18-year-old woman consulted the urological department with a chief complaint of urinary retention accompanied with high fever, headache and vomiting. The spinal fluid examination and cystometry revealed aseptic meningitis and atonic bladder, respectively. In both cases, the patients were treated with conservative therapy and bladder dysfunction was resolved after a few weeks. Eleven cases of urinary retention secondary to aseptic meningitis have been reported in the previous literature.


Assuntos
Meningite Asséptica/complicações , Retenção Urinária/etiologia , Adolescente , Feminino , Humanos , Masculino , Bexiga Urinaria Neurogênica/complicações
7.
Nippon Ganka Gakkai Zasshi ; 103(3): 237-42, 1999 Mar.
Artigo em Japonês | MEDLINE | ID: mdl-10214059

RESUMO

PURPOSE: To evaluate the chromatic aberration of the eyes with a poly (methylmethacrylate) (PMMA) intraocular lens or a soft acrylic intraocular lens (AcrySof), by comparing them with normal eyes. SUBJECTS AND METHODS: The longitudinal chromatic aberration (LCA) of the eye was measured by a modified chromoretinoscopy of Bobier & Sivak, for 48 eyes with a PMMA intraocular lens, 49 eyes with an AcrySof, and 27 eyes with a normal lens. In addition, these LCAs were calculated theoretically by the paraxial ray-tracing technique with a personal computer. RESULTS: The average values of the LCA between the wavelengths of 500 nm and 640 nm were 0.75 +/- 0.18 D (mean +/- standard deviation) in PMMA eyes, 1.20 +/- 0.22 D in AcrySof eyes, and 0.82 +/- 0.16 D in normal eyes. The calculated LCA was 0.64 D in the PMMA eye, 0.98 D in the AcrySof eye, and 0.74 D in the normal eye (Gullstrand's thematic eye). CONCLUSION: The PMMA eyes had chromatic aberrations almost equal to those of the normal eyes, whereas the AcrySof eyes have significantly larger aberrations. Therefore, we conclude that quality of the retinal image is reduced in eyes with an AcrySof lens.


Assuntos
Percepção de Cores , Pseudofacia/fisiopatologia , Acrilatos , Idoso , Humanos , Polimetil Metacrilato
8.
Opt Lett ; 24(12): 850-2, 1999 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-18073874

RESUMO

A time-resolved imaging technique for visualizing ultrafast propagation dynamics of intense light pulses in a medium has been demonstrated. The method probes the instantaneous birefringence induced by a pulse in the medium. Through consecutive femtosecond snapshot images of intense femtosecond laser pulses propagating in air, ultrafast temporal changes in the two-dimensional spatial distribution of the optical pulse intensity were clearly seen.

10.
Science ; 269(5227): 1080-3, 1995 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-17755528

RESUMO

Self-condensing vinyl polymerization was used to produce dendritic polymers with both highly branched structures and numerous reactive groups. A vinyl monomer will undergo self-polymerization if it contains a pendant group that can be transformed into an initiating moiety by the action of an external stimulus. The self-polymerization combines features of a classical vinyl polymerization process with those of a polycondensation because growth is accomplished by the coupling of reactive oligomers. Highly branched, irregular dendritic structures with a multiplicity of reactive functionalities are obtained by polymerization of 3-(1-chloroethyl)-ethenylbenzene.

11.
Jpn Circ J ; 58(2): 107-15, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8196152

RESUMO

To assess the clinical value of simultaneous dual myocardial imaging with iodine-123-beta-methyl-iodophenyl-pentadecanoic acid (123I-BMIPP) and thallium-201 (201Tl), myocardial imaging was performed at rest and during exercise in seven patients with coronary heart disease. When 123I-BMIPP and 201Tl images were compared, the initial exercise and resting images agreed 87% and 64%, respectively. In the initial resting images, the regional uptake of 123I-BMIPP was frequently less than that of 201Tl. The incidence of exercise-induced reversible defects by 201Tl in the Tl > BMIPP regions was significantly higher than that in the Tl = BMIPP regions (57% vs 4%, p < 0.01) and the incidence of coronary narrowing of more than 90% in the Tl > BMIPP regions was also significantly higher than that in the Tl = BMIPP regions (91% vs 38%, p < 0.01). In addition, this disparity (Tl > BMIPP) was found more frequently in regions with abnormal wall motion than in regions with normal wall motion (hypokinetic regions; 68%, severe hypokinetic or akinetic regions; 50%, vs normokinetic region; 4%, p < 0.01). In contrast, the uptake of 123I-BMIPP correlated closely with that of 201T1 in normal myocardium and the uptake of both 123I-BMIPP and 201Tl was severely reduced in myocardium with severe ischemia during exercise and prior infarction. These results indicate that dual myocardial imaging with 123I-BMIPP and 201Tl may provide a unique means of identifying patients with metabolically disturbed myocardium, such as hibernating and stunned myocardium.


Assuntos
Doença das Coronárias/diagnóstico por imagem , Ácidos Graxos , Coração/diagnóstico por imagem , Radioisótopos do Iodo , Iodobenzenos , Radioisótopos de Tálio , Idoso , Doença das Coronárias/fisiopatologia , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Contração Miocárdica , Tomografia Computadorizada de Emissão de Fóton Único
12.
Jpn Heart J ; 34(6): 763-72, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8164344

RESUMO

Carnitine deficiency has been demonstrated in diabetic hearts, and it is also well known that L-carnitine administration has a beneficial effect on cardiac function. Carnitine treatment would be expected to reduce the accumulation of long-chain acylcarnitine. However, many reports have shown that myocardial long-chain acylcarnitine levels were increased following treatment with L-carnitine in whole-heart studies. Since acylcarnitine exists in both the mitochondrial and cytosolic compartments, it is difficult to investigate changes in subcellular distribution by studying whole-heart preparations. The present study investigated the myocardial subcellular distribution of carnitine and its acyl derivatives in diabetic rats with or without L-carnitine treatment. Approximately 90% of total cellular carnitine was located in the cytosol in the diabetic hearts. Both mitochondrial and cytosolic levels of free carnitine and short-chain acylcarnitine were significantly decreased in the diabetic heart. However, the mitochondrial level of long-chain acylcarnitine was significantly increased. L-carnitine treatment reduced the mitochondrial level of long-chain acylcarnitine, but the cytosolic level of long-chain acylcarnitine was significantly increased. These results show that L-carnitine treatment prevents the accumulation of long-chain acylcarnitine in the mitochondrial space and then reduces the detergent effect of long-chain acylcarnitine on the mitochondrial membrane. We suggest that it is a possible mechanism of the beneficial effect of L-carnitine treatment on the diabetic heart.


Assuntos
Carnitina/metabolismo , Carnitina/farmacologia , Diabetes Mellitus Experimental/metabolismo , Miocárdio/metabolismo , Animais , Carnitina/análogos & derivados , Citosol/metabolismo , Masculino , Mitocôndrias Cardíacas/metabolismo , Ratos , Ratos Wistar
13.
Kaku Igaku ; 29(11): 1331-9, 1992 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-1484425

RESUMO

To evaluate the relationship between regional wall motion and 99mTc-methoxy-isobutyl-isonitrile (MIBI) uptake, ECG-gated single-photon emission computed tomography (SPECT) with 99mTc-MIBI was performed in 20 patients with prior myocardial infarction. The left ventricular images at end-diastole (ED) and end-systole (ES) were divided into 39 segments, respectively. Based on circumferential profile analysis, relative uptake (%EDc, %ESc), percent count increase (% delta C), and normalized percent count increase (% delta Cn) were analyzed in each segment and compared with regional wall motion indices assessed by echocardiography and left ventriculography. ECG-gated SPECT with 99mTc-MIBI provided high contrast tomograms of the left ventricular myocardium. %EDc and %ESc showed good correlations with regional wall motion indices. % delta C and % delta Cn, however, showed lower correlations compared with %EDc and %ESc. In conclusion, high-quality left ventricular images were obtained with 99mTc-MIBI ECG-gated SPECT, but quantitative analysis based on only percent count increase (% delta C) have limitations for evaluation of regional wall motion.


Assuntos
Imagem do Acúmulo Cardíaco de Comporta , Coração/diagnóstico por imagem , Infarto do Miocárdio/diagnóstico por imagem , Nitrilas , Compostos de Organotecnécio , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/fisiopatologia , Tecnécio Tc 99m Sestamibi , Tomografia Computadorizada de Emissão de Fóton Único
14.
Intern Med ; 31(8): 994-7, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1477473

RESUMO

Routine coronary angiography was performed in order to determine the incidence and clinical condition of coronary artery disease in 37 patients with arteriosclerosis obliterans or aortic aneurysm. Coronary angiography demonstrated significant stenosis in 12 (57%) of 21 patients with arteriosclerosis obliterans and in 7 (44%) of 16 patients with aortic aneurysm. The prevalence of risk factors for arteriosclerosis was similar for patients with arteriosclerosis obliterans and those with aortic aneurysm, and similar for patients with and without coronary artery stenosis. But coronary artery disease is often silent in patients with arteriosclerosis obliterans.


Assuntos
Aneurisma Aórtico/complicações , Arteriosclerose Obliterante/complicações , Doença da Artéria Coronariana/epidemiologia , Idoso , Angiografia , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/etiologia , Eletrocardiografia , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Volume Sistólico
15.
J Nucl Med ; 33(1): 6-13, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1530969

RESUMO

We studied whether emission computed tomography (ECT) with 123I-labeled 15-(p-iodophenyl)-3R,S-methylpentadecanoic acid (BMIPP) shows myocardial distribution different from 201Tl in hypertrophic cardiomyopathy. In 10 patients with asymmetric septal hypertrophy (ASH), 5 with diffuse hypertrophy and 2 with apical hypertrophy, ECT was acquired 30 min (early) and 4 hr (late) after injection of 123I-BMIPP at rest and was compared with ECT with 201Tl. In 10 patients with ASH, the relative regional uptake (RRU) of the septum was lower in the early 123I-BMIPP study than in the 201Tl study, although that of the posterior wall was similar. In the early and late 123I-BMIPP studies, the RRU of the septum was lower in 10 patients with ASH than in 7 without ASH, although that of the posterior wall was similar. In the 201Tl study, however, the RRU of both the septum and posterior wall was similar in those with and without ASH. Moreover, in 16 patients, the apparent left ventricular size was larger in the early 123I-BMIPP study than in the 201Tl study, which suggested reduced 123I-BMIPP uptake in the subendocardium. In patients with hypertrophic cardiomyopathy, thus, 123I-BMIPP imaging may reveal impaired regional fatty acid utilization, which is independent of regional perfusion.


Assuntos
Cardiomegalia/diagnóstico por imagem , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Ácidos Graxos , Radioisótopos do Iodo , Iodobenzenos , Tomografia Computadorizada de Emissão/métodos , Adulto , Idoso , Feminino , Septos Cardíacos/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Tálio
16.
Clin Nucl Med ; 15(6): 408-11, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2354580

RESUMO

Two patients with myocardial sarcoidosis are presented, both of whom underwent SPECT imaging with Tl-201 and Ga-67. The first had Ga-67 myocardial uptake with a Tl-201 defect, which disappeared with corticosteroid therapy. The second had multiple Tl-201 defects without Ga-67 uptake, which persisted despite corticosteroid therapy. Therefore, the combination of Tl-201 and Ga-67 imaging may be useful for recognizing myocardial sarcoidosis and for predicting the response to corticosteroid therapy.


Assuntos
Cardiomiopatias/diagnóstico por imagem , Radioisótopos de Gálio , Sarcoidose/diagnóstico por imagem , Radioisótopos de Tálio , Tomografia Computadorizada de Emissão , Corticosteroides/uso terapêutico , Cardiomiopatias/tratamento farmacológico , Feminino , Humanos , Pessoa de Meia-Idade , Sarcoidose/tratamento farmacológico , Tomografia Computadorizada de Emissão/métodos
17.
Jpn Circ J ; 52(3): 211-8, 1988 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2967384

RESUMO

We retrospectively compared the efficacy of percutaneous transluminal coronary angioplasty (PTCA) and intracoronary thrombolysis (ICT) in patients with acute myocardial infarction (AMI). The ICT group consisted of 62 consecutive patients who underwent ICT before the introduction of PTCA for AMI and who were considered to be candidates for PTCA based on review of their cine-films. The PTCA group consisted of 92 consecutive patients who underwent PTCA thereafter. The reperfusion rate was significantly higher in the PTCA group than in the ICT group (92.4% vs 71.4%, p less than 0.01) and the residual stenosis was significantly lower in the former. Furthermore, the incidences of reinfarction and post-infarction angina were significantly lower in the former than in the latter (3.3% vs 12.9%, p less than 0.05 and 6.5% vs 29.0%, p less than 0.001 respectively). Although the degree of improvement in left ventricular function was influenced by the result of reperfusion, it was not affected by the reperfusion method. Therefore, PTCA did not improve left ventricular function more than ICT unless ICT alone failed to achieve reperfusion.


Assuntos
Angioplastia com Balão , Doença das Coronárias/terapia , Trombose Coronária/terapia , Infarto do Miocárdio/terapia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
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