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1.
Phys Rev Lett ; 88(2): 021802, 2002 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-11801004

RESUMEN

We have studied two-body charmless decays of the B meson into the final states rho(0)rho(0), K(*0)rho(0), K(*0)K(*0), K(*0)K(*0), K(*+)rho(0), K(*+)K(*0), and K(*+)K(*-) using only decay modes with charged daughter particles. Using 9.7x10(6) BB pairs collected with the CLEO detector, we place 90% confidence level upper limits on the branching fractions (1.4-14.1)x10(-5), depending on final state and polarization.

2.
Phys Rev Lett ; 86(22): 5000-3, 2001 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-11384405

RESUMEN

We have measured the charge asymmetry in like-sign dilepton yields from B(0)B*(0) meson decays using the CLEO detector at the Cornell Electron Storage Ring. We find a(0)(ll) identical with[N(l(+)l(+))-N(l(-)l(-))]/[N(l(+)l(+))+N(l(-)l(-))] = +0.013+/-0.050+/-0.005. We combine this result with a previous, independent measurement and obtain Re(epsilon(B))/(1+ the absolute value of epsilon(B)(2)) = +0.0035+/-0.0103+/-0.0015 (uncertainties are statistical and systematic, respectively) for the CP impurity parameter, epsilon(B).

3.
Phys Rev Lett ; 86(17): 3718-21, 2001 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-11329307

RESUMEN

We have studied two-body charmless hadronic decays of B mesons into the final states straight phiK and phiK(*). Using 9.7 million B&Bmacr; pairs collected with the CLEO II detector, we observe the decays B- --> phiK- and B0--> phiK(*0) with the following branching fractions: B(B--->phiK-) = (5.5(+2.1)(-1.8)+/-0.6)x10(-6) and B(B0--> phiK(*0)) = (11.5(+4.5+1.8)(-3.7-1.7))x10(-6). We also see evidence for the decays B0-->phiK0 and B---> phiK(*-). However, since the statistical significance is not overwhelming for these modes, we determine upper limits of <12.3x10(-6) and <22.5x10(-6) ( 90% confidence level), respectively.

4.
Phys Rev Lett ; 86(13): 2737-41, 2001 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-11290027

RESUMEN

We analyze 9.7x10(6) B_B pairs recorded with the CLEO detector to determine the production ratio of charged to neutral B-meson pairs produced at the Upsilon(4S) resonance. We measure the rates for B0-->J/psiK((*)0) and B+-->J/psiK((*)+) decays and use the world-average B-meson lifetime ratio to extract the relative widths f(+-) / f(00) = gamma(Upsilon(4S)-->B+B-) / gamma(Upsilon(4S)-->B0 B-0)) = 1.04+/-0.07(stat)+/-0.04(syst). With the assumption that f(+-)+f(00) = 1, we obtain f(00) = 0.49+/-0.02(stat)+/-0.01(syst) and f(+-) = 0.51+/-0.02(stat)+/-0.01(syst). This production ratio and its uncertainty apply to all exclusive B-meson branching fractions measured at the Upsilon(4S) resonance.

5.
Phys Rev Lett ; 84(7): 1393-7, 2000 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-11017526

RESUMEN

We present the first observation of the decay B-->J/psistraight phiK. Using 9.6x10(6) B&Bmacr; meson pairs collected with the CLEO detector, we have observed ten fully reconstructed B-->J/psistraight phiK candidates, whereas the estimated background is 0.5+/-0.2 event. We obtain a branching fraction of B(B-->J/psistraight phiK) = (8. 8(+3.5)(-3.0)[stat]+/-1.3[syst])x10(-5). This is the first observed B meson decay requiring the creation of an additional s&smacr; quark pair.

7.
Pediatr Nephrol ; 10(4): 448-52, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8865241

RESUMEN

Tamm-Horsfall protein (THP), a glycoprotein with a molecular weight of 95 kilodaltons, is produced and secreted in the ascending loop of Henle. To evaluate the measurement of THP in the assessment of fetal renal development and function, we stained fetal kidney sections for THP and measured THP concentrations in 129 amniotic fluid samples from healthy pregnancies, together with other parameters such as transferrin, albumin, alpha 1- and beta 2-microglobulin. After the 16th week of gestation THP could be detected immunohistochemically in the distal tubular cells, but was not consistently detected by sandwich enzyme immunoassay until after the 20th week of gestation (detection limit 50 ng/ml). Between the 15th and 19th week of gestation THP was only detected occasionally, but after the 20th week of gestation the concentration increased significantly reaching levels of 0.4-4 mg/l at term. The THP concentration was lower in samples taken directly before birth than in the corresponding first urine after birth, indicating that THP is produced from the fetal kidney only and does not pass the placental barrier. This pattern was different from other proteins studied. Transferrin and albumin were significantly lower in the first urine voided, microglobulins remained unchanged, and the creatinine concentration increased. This indicates that maternal to fetal exchange or transport is likely for most of the other proteins. Measurement of THP concentrations, in addition to other proteins in the amniotic fluid, can improve fetal renal assessment, but because the range of THP concentrations is wide accurate predictions are still not possible.


Asunto(s)
Túbulos Renales/embriología , Túbulos Renales/metabolismo , Mucoproteínas/metabolismo , Proteínas Gestacionales/metabolismo , alfa-Globulinas/metabolismo , Líquido Amniótico/química , Biomarcadores , Creatinina/sangre , Femenino , Edad Gestacional , Humanos , Inmunohistoquímica , Peso Molecular , Embarazo , Transferrina/metabolismo , Uromodulina
13.
Med Pediatr Oncol ; 25(6): 479-84, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7565313

RESUMEN

Pleuro-pulmonary blastoma is a rare malignant lung tumor in children and distinct from ordinary pulmonary blastoma of adulthood. Combination chemotherapy plays an important role in the treatment of this tumor, but so far no attempt of high dose chemotherapy with subsequent bone marrow or blood stem cell transplantation has been published. The case is reported of a 2-year-old boy with pleuro-pulmonary blastoma who achieved partial remission with conventional chemotherapy and surgery. Subsequent administration of high dose melphalan, etoposide, and carboplatin, followed by autologous blood stem cell transplantation resulted in a 3-month disease-free interval but did not prevent eventual local recurrence, leading to death within a few weeks. Clinical presentation, pathology, management, and prognosis are discussed and the literature reviewed.


Asunto(s)
Neoplasias Pulmonares , Neoplasias Pleurales , Blastoma Pulmonar , Preescolar , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/terapia , Masculino , Neoplasias Pleurales/diagnóstico , Neoplasias Pleurales/terapia , Blastoma Pulmonar/diagnóstico , Blastoma Pulmonar/terapia
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