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1.
Phys Rev Lett ; 98(13): 132503, 2007 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-17501196

RESUMEN

A rotational band has been unambiguously observed in an odd-proton transfermium nucleus for the first time. An in-beam gamma-ray spectroscopic study of 101/251Md has been performed using the gamma-ray array JUROGAM combined with the gas-filled separator RITU and the focal plane device GREAT. The experimental results, compared to Hartree-Fock-Bogolyubov calculations, lead to the interpretation that the rotational band is built on the [521]1/2(-) Nilsson state.

2.
Phys Rev Lett ; 97(6): 062501, 2006 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-17026165

RESUMEN

Lifetimes of prolate intruder states in 186Pb and oblate intruder states in 194Po have been determined by employing, for the first time, the recoil-decay tagging technique in recoil distance Doppler-shift lifetime measurements. In addition, lifetime measurements of prolate states in 188Pb up to the 8+ state were carried out using the recoil-gating method. The B(E2) values have been deduced from which deformation parameters |beta2|=0.29(5) and |beta2|=0.17(3) for the prolate and the oblate bands, respectively, have been extracted. The results also shed new light on the mixing between different shapes.

3.
Phys Rev Lett ; 96(23): 232501, 2006 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-16803374

RESUMEN

The reduced transition probabilities B(E2;0(+) --> 2(+)(1)) of the neutron-rich (74)Zn and (70)Ni nuclei have been measured by Coulomb excitation in a (208)Pb target at intermediate energy. These nuclei have been produced at Grand Accélérateur National d'Ions Lourds via interactions of a 60A MeV (76)Ge beam with a Be target. The B(E2) value for (70)Ni(42) is unexpectedly large, which indicates that neutrons added above N=40 strongly polarize the Z=28 proton core. In the Zn isotopic chain, the steep rise of B(E2) values beyond N=40 continues up to (74)Zn(44). The enhanced proton core polarization in (70)Ni is attributed to the monopole interaction between the neutron in the g(9/2) and protons in the f(7/2) and f(5/2) spin-orbit partner orbitals. This interaction could result in a weakening of magicity in (78)Ni(50).

4.
Phys Rev Lett ; 90(8): 082502, 2003 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-12633421

RESUMEN

A new isomeric 0(+) state was identified as the first excited state in the self-conjugate (N=Z) nucleus 72Kr. By combining for the first time conversion-electron and gamma-ray spectroscopy with the production of metastable states in high-energy fragmentation, the electric-monopole decay of the new isomer to the ground state was established. The new 0(+) state is understood as the band head of the known prolate rotational structure, which strongly supports the interpretation that 72Kr is one of the rare nuclei having an oblate-deformed ground state. This observation gives in fact the first evidence for a shape isomer in a N=Z nucleus.

5.
Phys Rev Lett ; 89(20): 202501, 2002 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-12443472

RESUMEN

The spectrum of prompt conversion electrons emitted by excited 254No nuclei has been measured, revealing discrete lines arising from transitions within the ground state band. A striking feature is a broad distribution that peaks near 100 keV and comprises high multiplicity electron cascades, probably originating from M1 transitions within rotational bands built on high K states.

6.
Phys Rev Lett ; 87(7): 072501, 2001 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-11497885

RESUMEN

Excited states in (216)Th were investigated via prompt and delayed gamma decays and the recoil-decay tagging method. The decay schemes of the I(pi) = (8+), t(1/2) = 128(8) micros, the I(pi) = (11-), t(1/2) = 615(55) ns, and the I(pi) = (14+), t(1/2) > or = 130 ns isomers were established. The configuration pi h(9/2)f(7/2) is assigned to the I(pi) = (8+) isomer, which implies that the h(9/2) and f(7/2) states are nearly degenerate. This is ascribed to increased binding of the f(7/2) orbital by its coupling to a low-lying I(pi) = (3-) state at E(x) = 1687 keV. The role of octupole and pairing correlations for a Z = 92 shell closure prediction is discussed on the basis of shell model calculations.

10.
Ann Cardiol Angeiol (Paris) ; 43(10): 594-9, 1994 Dec.
Artículo en Francés | MEDLINE | ID: mdl-7864552

RESUMEN

Left ventricular hypertrophy is now recognized to be a major and independent risk factor of mortality and morbidity. Although all classes of antihypertensives are able to reduce left ventricular mass, two recent metaanalyses have shown that ACE inhibitors are the most effective. The antihypertensive efficacy of perindopril in man is accompanied with a significant improvement in the functional properties of large arteries and with a reduction of LVH. This study was designed to assess the course of left ventricular mass by echocardiography in a population of 893 hypertensive patients with moderate left ventricular hypertrophy, treated with perindopril for 3 months. A significant fall in blood pressure was observed by the 6th week. The morphological and functional echocardiographic parameters on a large population provided more valid statistical results than in a small series. The left ventricular cavity was found to undergo symmetrical remodelling, adapted to the new haemodynamic status. The reduction of the thickness of the wall was in line with the reduction of the size of the ventricular chamber, and left ventricular mass was reduced by 8% (p < 0.001). Systolic function was preserved and diastolic function was improved. In particular, the E/A ratio was increased by 8% (p < 0.001) and the duration of isometric relaxation was decreased by 11 ms (p < 0.02). This improvement of filling was confirmed by the reduction of the diameter of the left atrium by 0.2 mm (p < 0.001). This open study in 893 patients therefore confirmed that perindopril corrects LVH in hypertensive patients.


Asunto(s)
Antihipertensivos/uso terapéutico , Hipertensión/complicaciones , Hipertrofia Ventricular Izquierda/tratamiento farmacológico , Indoles/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Antihipertensivos/farmacología , Ecocardiografía , Femenino , Hemodinámica/efectos de los fármacos , Humanos , Hipertensión/tratamiento farmacológico , Hipertrofia Ventricular Izquierda/etiología , Hipertrofia Ventricular Izquierda/fisiopatología , Indoles/farmacología , Masculino , Persona de Mediana Edad , Contracción Miocárdica/efectos de los fármacos , Perindopril , Factores de Tiempo , Función Ventricular Izquierda/efectos de los fármacos
12.
Hepatology ; 16(3): 630-6, 1992 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1380479

RESUMEN

Recent studies have shown that hepatitis C virus antibodies are present in a large proportion of patients with autoimmune hepatitis type 2. We have studied 83 patients with liver/kidney microsome antibody-positive type 1 hepatitis. Hepatitis C virus antibodies were sought in every case by second-generation tests (hepatitis C virus enzyme-linked immunosorbent assay and recombinant immunoblot assay). Hepatitis C virus RNA sequences were sought in 22 patients (12 with recombinant immunoblot assay-positive results and 10 with recombinant immunoblot assay-negative results) by means of polymerase chain reaction and by use of primers located in the 5' noncoding region. Sixty-four patients (77%) had positive results for hepatitis C virus antibodies in the enzyme-linked immunosorbent assay test, and 41 (49.3%) were confirmed by recombinant immunoblot assay. Hepatitis C virus RNA sequences were found in all the recombinant immunoblot assay-positive patients but in none of the 10 who were recombinant immunoblot assay-negative. The recombinant immunoblot assay-negative patients were younger than those who were positive (13 +/- 11 vs. 50 +/- 11 years) and had higher gamma-globulin levels and liver/kidney microsome antibody-positive type 1 titers (61% had a titer of 1:1,000 or more, vs. only 17% of the recombinant immunoblot assay-positive patients).(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Autoanticuerpos/sangre , Enfermedades Autoinmunes/inmunología , Anticuerpos Antihepatitis/sangre , Hepatitis C/inmunología , Adolescente , Adulto , Anciano , Alanina Transaminasa/sangre , Enfermedades Autoinmunes/sangre , Enfermedades Autoinmunes/clasificación , Compuestos de Bretilio , Niño , Preescolar , Ensayo de Inmunoadsorción Enzimática , Femenino , Hepatitis C/sangre , Hepatitis C/clasificación , Anticuerpos contra la Hepatitis C , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa
13.
Rev Prat ; 41(4): 332-5, 1991 Feb 01.
Artículo en Francés | MEDLINE | ID: mdl-2008584

RESUMEN

Some viral infections, such as rubella, cytomegalovirus and parvovirus B 19 infections or varicella, are particularly feared in pregnant women in view of the risk of foetal infection. Laboratory tests play an important role since there is no other way of diagnosing the infection and determining whether it is primary or secondary, a distinction which to a great extent conditions the severity of the foetal disease. However, no virological diagnosis can be made unless the examinations needed are prescribed correctly and at the right moment. The diagnosis of rubella is now well codified, but that of CMV infection still suffers from interpretation problems and that of parvovirus B 19 infection can only be obtained from specialized laboratories. The application of rapid diagnostic methods and molecular biology to foetal specimen collected under ultrasonography should provide a more accurate prenatal diagnosis of congenital viral infections.


Asunto(s)
Intercambio Materno-Fetal , Complicaciones Infecciosas del Embarazo/microbiología , Virosis/microbiología , Femenino , Humanos , Embarazo , Complicaciones Infecciosas del Embarazo/diagnóstico , Virosis/diagnóstico , Virosis/epidemiología , Virosis/transmisión
14.
Infect Immun ; 57(3): 932-6, 1989 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2917793

RESUMEN

Using axenic quails fed a diet containing lactose, we have investigated the potentially pathogenic roles of six Clostridium butyricum strains of human origin. Three strains (CB155-3, CB1002, and CB203-1) isolated from neonatal necrotizing enterocolitis patients and two of three strains (CB19-1 and CB25-2) isolated from healthy newborns led to cecal or crop lesions or both similar to those observed in human neonatal necrotizing enterocolitis: thickening of the cecal wall with gas cysts, hemorrhagic ulcerations, and necrotic areas. The lactose-negative strain (CB46-1) did not develop any lesions. The neuraminidase-producing strain (CB155-3) caused lesions in all monoassociated quails, whereas the other strains caused lesions in 28 to 85% of animals. Removal of dietary lactose suppressed all pathological incidence. These results show that lactose fermentation is a prerequisite in these pathological changes and stress the roles played by both the strain and the host in the expression of C. butyricum enteropathogenicity.


Asunto(s)
Clostridium/patogenicidad , Enterocolitis Seudomembranosa/microbiología , Codorniz/fisiología , Animales , Ciego/microbiología , Ciego/patología , Modelos Animales de Enfermedad , Enterocolitis Seudomembranosa/patología , Enterocolitis Seudomembranosa/fisiopatología , Vida Libre de Gérmenes , Humanos , Recién Nacido
15.
Lab Anim Sci ; 33(2): 199-202, 1983 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6855193

RESUMEN

In order to study bile secretion in the fistulated pig, an apparatus which reinfused the secreted bile at a rate reflecting the secretion rate, was used. The essential parts were a glass container equipped with two platinum wire electrodes, an electronic relay, a stop valve, and a peristaltic pump. This apparatus allowed a reinfusion of collected bile in a volume determined by the position of one of the electrodes, the recording of bile flow, and a continuous sampling for chemical analysis.


Asunto(s)
Conductos Biliares/metabolismo , Bilis/metabolismo , Porcinos/fisiología , Animales , Conductos Biliares/cirugía , Fístula Biliar , Manejo de Especímenes/métodos , Manejo de Especímenes/veterinaria , Porcinos/cirugía
16.
Reprod Nutr Dev (1980) ; 23(4): 765-73, 1983.
Artículo en Inglés | MEDLINE | ID: mdl-6612097

RESUMEN

The aim of this work was to investigate the effects on bile secretion of flow rate and site of reinfusion of the collected bile to the animal. Thirty-two pigs weighing 50 +/- 3 kg at the beginning of the experiment were fitted with a reentrant fistula in the lower common bile duct and in the upper duodenum. Bile collected from the bile duct was reinfused in four different ways (four groups of 8 animals each): into the duodenum or the lower common bile duct at a constant flow rate using a peristaltic pump, or into the duodenum or the lower common bile duct at a rate mimicking the flow rate of the secretion using an automatic apparatus. Reinfusing the bile into the lower common bile duct at a rate mimicking the secretion rate provided a daily bile acid production about 21% higher than the level recorded with the other three methods. This was mainly due to a higher bile acid concentration since the bile flow was only slightly affected by the treatment.


Asunto(s)
Bilis/metabolismo , Animales , Ácidos y Sales Biliares/metabolismo , Fístula Biliar , Castración , Conducto Colédoco , Duodeno , Cinética , Masculino , Porcinos
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