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1.
Phys Rev Lett ; 105(14): 145003, 2010 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21230839

RESUMO

Reversed-shear Alfvén eigenmodes were observed for the first time in a helical plasma having negative q0'' (the curvature of the safety factor q at the zero shear layer). The frequency is swept downward and upward sequentially via the time variation in the maximum of q. The eigenmodes calculated by ideal MHD theory are consistent with the experimental data. The frequency sweeping is mainly determined by the effects of energetic ions and the bulk pressure gradient. Coupling of reversed-shear Alfvén eigenmodes with energetic ion driven geodesic acoustic modes generates a multitude of frequency-sweeping modes.

2.
Semin Oncol ; 24(2 Suppl 6): S6-122-S6-129, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9151927

RESUMO

Thirty-two patients with hepatocellular carcinoma (HCC) were treated with YNK-01, a prodrug of cytarabine for oral administration. A dose of 200 mg/d of YNK-01 was administered to 17 cases and 300 mg/d to 15 cases. One course was 2 weeks in duration, and this was repeated every 4 weeks for as long as the patients were able to tolerate it. There were five partial responses (15%) and 13 patients with no change (41%). A higher partial response rate was observed in the 300 mg/d group (27%) compared with the 200 mg/d group (6%). The average durations of partial response and no change were approximately 4 and 3 months, respectively. The main side effects of YNK-01 were anemia, leukopenia, thrombocytopenia, and symptoms of the alimentary tract (nausea, anorexia, diarrhea, etc). These results suggest that YNK-01 is a potentially useful oral agent for chemotherapy of hepatocellular carcinoma.


Assuntos
Antineoplásicos/administração & dosagem , Arabinonucleotídeos/administração & dosagem , Carcinoma Hepatocelular/tratamento farmacológico , Monofosfato de Citidina/análogos & derivados , Neoplasias Hepáticas/tratamento farmacológico , Pró-Fármacos/administração & dosagem , Administração Oral , Idoso , Antineoplásicos/efeitos adversos , Arabinonucleotídeos/efeitos adversos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Monofosfato de Citidina/administração & dosagem , Monofosfato de Citidina/efeitos adversos , Feminino , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Pró-Fármacos/efeitos adversos , Tomografia Computadorizada por Raios X
3.
Phys Rev Lett ; 84(6): 1216-9, 2000 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-11017482

RESUMO

The confinement characteristics of large net-current-free plasmas heated by neutral-beam injection have been investigated in the Large Helical Device (LHD). A systematic enhancement in energy-confinement times from the scaling derived from the medium-sized heliotron/torsatron experiments have been observed, which is attributed to the edge pedestal. The core confinement is scaled with the Bohm term divided by the square root of the gyro radii. The comparative analysis using a dimensionally similar discharge in the Compact Helical System indicates gyro-Bohm dependence in the core and transport improvement in the edge region of LHD plasmas.

4.
Phys Rev Lett ; 84(1): 103-6, 2000 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-11015845

RESUMO

In LHD discharges a significant enhancement of the global energy confinement has been achieved for the first time in a helical device with an edge thermal barrier, which exhibits a sharp gradient at the edge of the temperature profile. Key features associated with the barrier are quite different from those seen in tokamaks: (i) almost no change in particle (including impurity) transport, (ii) a gradual formation of the barrier, (iii) a very high ratio of the edge temperature to the average temperature, and (iv) no edge relaxation phenomenon. These features are very attractive in applying the thermal barrier to future reactor grade devices.

5.
Seishin Shinkeigaku Zasshi ; 98(7): 441-59, 1996.
Artigo em Japonês | MEDLINE | ID: mdl-8911088

RESUMO

123I-IMP SPECT (SPECT) has been widely used in clinical neuropsychiatry for establishing the clinical diagnosis, and evaluating the course of the disease. However, little is known about the significance of alterations in SPECT. In this paper, we present comparative study between alterations in SPECT and neuropathological findings in the case of Alzheimer's disease (AD). The patient, a 59-year-old female, began to show memory disturbance and the left hemisphere disturbances, non-fluent aphasia, but right hemisphere disturbances, constructional apraxia, visuo-spatial dysfunctions were not notable at the early stage. The neuroimaging also revealed left-side dominant cerebral atrophy in MRI and left-side dominant hypoactive regions in SPECT (especially in parietal lobe). Memory disturbance and non-fluent aphasia gradually progressed after admission. Then, mirror phenomenon and Bálint's syndrome appeared at the age of 63 years. In the advanced stage, hypoactive regions in SPECT were expanded into temporal and frontal areas. The laterality observed at the early stage became unremarkable. The patient died from heart failure at 64 years. Pathological diagnosis was AD. Eleven ROI (region of interests) were determined on each hemisphere in transverse SPECT image. We calculated ROI% (each ROI count/ROI count at central cerebellum). Neuronal cell count (NCC) and amyloid beta protein deposited areas (BDA) were estimated using 3 serial sections stained with Nissl's method and immunostained for amyloid using monoclonal antibody raised against synthetic A beta, mcAb 90/12. Digitized images based on photographs were analyzed with NIH-image 1.45. NCC decreased in number in frontal, temporal, and parietal lobes. Significant asymmetrical reduction of NCC (lt. < rt.) was observed in orbital, superior temporal and angular gyri (p < 0.01). BDA in superior parietal lobule, superior temporal gyrus and superior, middle, inferior frontal gyri were larger than those in precentral gyrus and visual cortex. Asymmetry of BDA (lt. > rt.) was significant in middle temporal gyrus (p < 0.01). ROI% at the early stage was correlated with corresponding NCC (r = 0.49, p < 0.05) and BDA (r = -0.55, p < 0.01), but at the advanced stage was not significantly correlated with corresponding NCC (r = 0.26) and BDA (r = -0.20). It is evident that SPECT shows good correlation with clinical features and pathological alterations during the course of AD. Our observations imply that the changes in SPECT usually precede the appearance of the clinical symptoms. SPECT is very sensitive in detecting the functional decline in certain regions of the CNS. In the case of AD, the hypoactive regions in SPECT at the early stage may indicate functional decline of the neuronal cells, and at the advanced stage, these may indicate the degree of pathological changes, especially neuronal loss and amyloid beta protein deposition.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Tomografia Computadorizada de Emissão de Fóton Único , Feminino , Humanos , Pessoa de Meia-Idade
12.
Phys Rev Lett ; 97(5): 055002, 2006 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-17026108

RESUMO

In reduced recycling discharges in the Large Helical Device, a super dense core plasma develops when a series of pellets are injected. A core region with density as high as 4.5 x 10(20) m(-3) and temperature of 0.85 keV is maintained by an internal diffusion barrier with very high-density gradient. These results may extrapolate to a scenario for fusion ignition at very high density and relatively low temperature in helical devices.

13.
Br J Cancer ; 88(10): 1543-8, 2003 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-12771919

RESUMO

Carcinoma cells can lose their epithelial cell characteristics and dedifferentiate into a fibroblast-like cell during progression of a neoplasm. Aberrant expression of oligomeric transcriptional complexes contributes to progression of carcinomas. Although individual transcription factors initiating progression remain unknown, LIM-only protein (LMO) and LIM-domain binding protein (LDB) negatively regulate breast carcinoma cell differentiation. In this study, we investigated the expression of LMO4 and LDB in squamous cell carcinomas of the oral cavity. LMO4 mRNA was amplified in four of six carcinoma tissues and eight of 12 carcinoma cell lines, and LDB1 in three carcinoma tissues and 11 cell lines examined. Immunoprecipitation studies revealed that LMO4 and LDB1 interact with each other in the nuclear milieu of the carcinoma cells indicating the presence of an LMO4-LDB1-mediated transcription complex. Both LMO4 and LDB1 proteins were preferentially localised in the nuclei of carcinoma cells at the invasive front and the immunoreactivity was increased in less-differentiated carcinoma tissues (P<0.01). Carcinoma cells metastasised to the cervical lymph nodes with increased immunoreactivity compared to the primary site of neoplasm (P<0.05). These data suggest that the LMO4-LDB1 complexes may be involved in carcinoma progression possibly through dedifferentiation of squamous carcinoma cells of the oral cavity.


Assuntos
Carcinoma de Células Escamosas/patologia , Diferenciação Celular , Transformação Celular Neoplásica , Proteínas de Ligação a DNA/farmacologia , Neoplasias Bucais/patologia , Proteínas Oncogênicas/farmacologia , Carcinoma de Células Escamosas/genética , Núcleo Celular , Primers do DNA , Proteínas de Ligação a DNA/análise , Progressão da Doença , Humanos , Proteínas com Domínio LIM , Neoplasias Bucais/genética , Metástase Neoplásica , Proteínas Oncogênicas/análise , Reação em Cadeia da Polimerase , Fatores de Transcrição , Células Tumorais Cultivadas
14.
Biochemistry ; 16(13): 2860-6, 1977 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-18162

RESUMO

The origin of the skeletal carbons in the lactone ring of 16-membered macrolide antiobiotics has been studied. 13C-labeled antibiotics leucomycin and tylosin, have been obtained from the culture broth of Streptomyces kitasatoensis 66-14-3 and Streptomyces fradiae C-373, respectively in the presence of appropriate 13C-labeled precursors, and 13C NMR spectra of the antibiotics thus obtained have been measured. It was shown that the aglycone of leucomycin A3 is derived from five acetates, one propionate, one butyrate, and an unknown precursor corresponding to two carbons. The formyl carbon which is characteristic of the basic 16-membered macrolides orginates from C-4 butyrate. On the other hand, the aglycone of tylosin is formed from two acetates, five propionates and one butyrate. Butyric acid and ethylmalonic acid are metabolized to propionyl-CoA or methylmolonyl-CoA through a pathway involving methylmalonyl-CoA mutase, and subsequently incorporated into the lactone ring of tylosin.


Assuntos
Antibacterianos/biossíntese , Leucomicinas/biossíntese , Streptomyces/metabolismo , Acetatos/metabolismo , Butiratos/metabolismo , Fenômenos Químicos , Química , Espectroscopia de Ressonância Magnética , Malonatos/metabolismo , Metilmalonil-CoA Mutase/metabolismo , Modelos Biológicos , Propionatos/metabolismo
15.
Phys Rev Lett ; 88(5): 055005, 2002 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-11863738

RESUMO

In the Large Helical Device plasma discharges, the size of an externally imposed island with mode number ( n/m = 1/1) decreases substantially when the plasma is collisionless ( nu(*)< approximately 1) and the beta is finite ( > approximately 0.1%) at the island location. For the collisional plasmas with finite beta, on the other hand, the size of the island increases. However, there is a threshold in terms of the vacuum island size below which the island enlargement is not seen.

16.
Phys Rev Lett ; 86(23): 5297-300, 2001 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-11384482

RESUMO

Recent large helical device experiments revealed that the transition from ion root to electron root occurred for the first time in neutral-beam-heated discharges, where no nonthermal electrons exist. The measured values of the radial electric field were found to be in qualitative agreement with those estimated by neoclassical theory. A clear reduction of ion thermal diffusivity was observed after the mode transition from ion root to electron root as predicted by neoclassical theory when the neoclassical ion loss is more dominant than the anomalous ion loss.

17.
Phys Rev Lett ; 87(13): 135002, 2001 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-11580597

RESUMO

It was observed that the vacuum magnetic island produced by an external error magnetic field in the large helical device shrank in the presence of plasma. This was evidenced by the disappearance of flat regions in the electron temperature profile obtained by Thomson scattering. This island behavior depended on the magnetic configuration in which the plasmas were produced.

18.
Phys Rev Lett ; 90(20): 205001, 2003 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-12785901

RESUMO

Sawtooth oscillations have been observed in current-carrying helical plasmas by using electron-cyclotron-emission diagnostics in the Large Helical Device. The plasma current, which is driven by neutral beam injection, reduces the beta threshold of the sawtooth oscillation. When the central q value is increased due to the plasma current, the core region crashes, and, when it is decreased, the edge region crashes annularly. Observed rapid mixture of the plasma in the limited region suggests that these sawtooth crashes are reconnection phenomena. Unlike previous experiments, no precursor oscillation has been observed.

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