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1.
Phys Rev Lett ; 92(5): 054802, 2004 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-14995314

RESUMEN

For high luminosity in electron-positron linear colliders, it is essential to generate low vertical emittance beams. We report on the smallest vertical emittance achieved in single-bunch-mode operation of the Accelerator Test Facility, which satisfies the requirement of the x-band linear collider. The emittances were measured with a laser-wire beam-profile monitor installed in the damping ring. The bunch length and the momentum spread of the beam were also recorded under the same conditions. The smallest vertical rms emittance measured at low intensity is 4 pm at a beam energy of 1.3 GeV, which corresponds to the normalized emittance of 1.0x1.0(-8) m. It increases by a factor of 1.5 for a bunch intensity of 10(10) electrons. The measured data agreed to the calculation of intrabeam scattering within much better than a factor of 2.

2.
Phys Rev Lett ; 88(19): 194801, 2002 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-12005637

RESUMEN

Electron beams with the lowest, normalized transverse emittance recorded so far were produced and confirmed in single-bunch-mode operation of the Accelerator Test Facility at KEK. We established a tuning method of the damping ring which achieves a small vertical dispersion and small x-y orbit coupling. The vertical emittance was less than 1% of the horizontal emittance. At the zero-intensity limit, the vertical normalized emittance was less than 2.8 x 10(-8) rad m at beam energy 1.3 GeV. At high intensity, strong effects of intrabeam scattering were observed, which had been expected in view of the extremely high particle density due to the small transverse emittance.

4.
Phys Rev Lett ; 88(4): 041803, 2002 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-11801107

RESUMEN

Additional evidence for the rare kaon decay K+-->pi+nu(nu) has been found in a new data set with comparable sensitivity to the previously reported result. One new event was observed in the pion momentum region examined, 211pi+nu(nu)) = 1.57(+1.75)(-0.82)x10(-10).

5.
Phys Rev Lett ; 85(23): 4856-9, 2000 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-11102135

RESUMEN

We have performed a measurement of the K+-->pi(+)pi(0)gamma decay and have observed 2x10(4) events. The best fit to the decay spectrum gives a branching ratio for direct photon emission of (4.7+/-0.8+/-0. 3)x10(-6) in the pi(+) kinetic energy region of 55 to 90 MeV and requires no component due to interference with inner bremsstrahlung.

6.
Phys Rev Lett ; 84(17): 3768-70, 2000 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-11019201

RESUMEN

A search for additional evidence for the rare kaon decay K+-->pi(+)nunu; has been made with a new data set comparable in sensitivity to the previous exposure that produced a single event. No new events were found in the pion momentum region examined, 211pi(+)nunu;) = 1.5(+3.4)(-1.2)x10(-10).

7.
Phys Rev Lett ; 85(11): 2256-9, 2000 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-10977985

RESUMEN

We report the first measurement of a structure-dependent component in the decay K+-->&mgr;(+)nu(&mgr;)gamma. Using the kinematic region where the muon kinetic energy is greater than 137 MeV and the photon energy is greater than 90 MeV, we find that the absolute value of the sum of the vector and axial-vector form factors is |F(V)+F(A)| = 0.165+/-0.007+/-0.011. This corresponds to a branching ratio of B(SD+) = (1.33+/-0.12+/-0.18)x10(-5). We also set the limit -0. 04

8.
Endocr J ; 46(1): 59-66, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10426568

RESUMEN

We report a case of preclinical Cushing's syndrome in a 54-year-old male associated with bilateral adrenocortical tumours. Physical findings and general laboratory data were unremarkable except for mild hypertension (158/90 mmHg) and impaired glucose tolerance. Endocrinological evaluation revealed the presence of autonomous cortisol secretion including unsuppressible serum cortisol by 8 mg dexamethasone test (11 microg/dl), high serum DHEA-S (3580 ng/ml, normal: 400-3500) and increased urinary 17-KS excretion (31.0-35.8 mg/day, normal: 5.8-21.3). CT scan demonstrated the presence of tumours in both adrenals and bilateral adrenalectomy was subsequently performed. Histological examination of the resected specimens revealed an adrenocortical carcinoma on the right side and an adenoma on the left side with noticeable cortical atrophy in non-neoplastic adrenals. Immunohistochemical study of steroidogenic enzymes demonstrated that all the steroidogenic enzymes involved in cortisol biosynthesis were expressed in both right and left adrenal tumours. Enzymatic activities of 21, 17alpha, 18, 11beta-hydroxylases were detected in both right and left adrenals except for the absence of 11beta-hydroxylase activity in the left adrenal adenoma. Results of in vitro tissue steroidogenesis examined in short-term tissue culture of the specimens revealed no significant differences between carcinoma and adenoma in cortisol production, but the production of adrenal androgens in carcinoma was significantly higher than that in adenoma, which may indicate the importance of evaluating adrenal androgen levels in patients with adrenocortical neoplasms.


Asunto(s)
Adenoma/diagnóstico , Neoplasias de la Corteza Suprarrenal/diagnóstico , Carcinoma/diagnóstico , Síndrome de Cushing/diagnóstico , Sulfato de Deshidroepiandrosterona/sangre , 17-Cetosteroides/orina , Adenoma/patología , Adenoma/cirugía , Neoplasias de la Corteza Suprarrenal/patología , Neoplasias de la Corteza Suprarrenal/cirugía , Adrenalectomía , Carcinoma/patología , Carcinoma/cirugía , Técnicas de Cultivo , Dexametasona , Glucocorticoides , Humanos , Hidrocortisona/sangre , Hidrocortisona/metabolismo , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Neoplasias Primarias Múltiples/diagnóstico , Neoplasias Primarias Múltiples/patología , Neoplasias Primarias Múltiples/cirugía , Esteroide Hidroxilasas/análisis , Tomografía Computarizada por Rayos X
11.
Nihon Koshu Eisei Zasshi ; 42(5): 338-45, 1995 May.
Artículo en Japonés | MEDLINE | ID: mdl-7647351

RESUMEN

A survey was performed of acute encephalitis and bacterial meningitis in infancy and childhood from 1984 to 1993 using a questionnaire directed to departments of pediatrics in large hospitals in Aichi prefecture. The case records for 391 patients with acute encephalitis including related diseases and 328 patients with bacterial meningitis were obtained from 63 hospitals. Of 391 patients with acute encephalitis, 224 were male and 167 were female. Of 328 patients with bacterial meningitis, 200 were male and 128 were female. Sex ratio were 1.3, 1.6 respectively. Of the patients, 52.4% of encephalitis and 84.8% of meningitis were under 4 years of age and 0 year olds made up 53.7% of the latter. The causes of these diseases were confirmed in 38.7% and 82.9% of the encephalitis and meningitis patients, respectively, etiologically. In encephalitis, rubella virus was the most frequent with 29 cases, followed by measles virus (27 cases), herpes simplex virus (24) and varicella-zostervirus (19). In meningitis H. influenzae (95 cases), S. pneumoniae (56), Group B streptococcus (41) and E. coli (27) were frequently diagnosed. These diseases showed respective patterns of age distribution and clinical course, and moreover, the increases in their onset were clearly related to the prevalence of causal infections. Therefore, the results of this study should be utilized in the development of administrative measures for prevention of these diseases.


Asunto(s)
Encefalitis/epidemiología , Meningitis Bacterianas/epidemiología , Enfermedad Aguda , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Japón/epidemiología , Masculino , Pronóstico
13.
Life Sci ; 54(16): PL253-9, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-8152333

RESUMEN

The effect of recombinant human erythropoietin (r-HuEPO, 0.1 to 2.0 U/ml) on endothelin-1 (ET-1) release was examined in isolated hind legs perfused with Krebs-Ringer solution from normal rats. r-HuEPO increased immunoreactive (ir-) ET-1 release in a dose-dependent fashion; the maximal percent increment in ir-ET-1 release evoked by r-HuEPO (2.0 U/ml) was about +210% over the basal rate of release. However, r-HuEPO showed no effect on release of angiotensin II, thromboxane B2 or vasodilatory prostaglandin I2 from the vasculature. These results not only provide direct evidence that r-HuEPO has the potential to specifically stimulate release of ET-1 from peripheral vascular beds, but, hence, suggest a contributory role of ET-1 in r-HuEPO-induced hypertension in anemic human subjects undergoing r-HuEPO therapy.


Asunto(s)
Vasos Sanguíneos/efectos de los fármacos , Endotelinas/metabolismo , Eritropoyetina/farmacología , 6-Cetoprostaglandina F1 alfa/metabolismo , Angiotensina I/metabolismo , Angiotensina II/metabolismo , Animales , Vasos Sanguíneos/metabolismo , Miembro Posterior/irrigación sanguínea , Humanos , Masculino , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes/farmacología , Tromboxano B2/metabolismo
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