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1.
Phys Rev Lett ; 122(19): 192501, 2019 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-31144924

RESUMEN

We present a precision analysis of the ^{136}Xe two-neutrino ßß electron spectrum above 0.8 MeV, based on high-statistics data obtained with the KamLAND-Zen experiment. An improved formalism for the two-neutrino ßß rate allows us to measure the ratio of the leading and subleading 2νßß nuclear matrix elements (NMEs), ξ_{31}^{2ν}=-0.26_{-0.25}^{+0.31}. Theoretical predictions from the nuclear shell model and the majority of the quasiparticle random-phase approximation (QRPA) calculations are consistent with the experimental limit. However, part of the ξ_{31}^{2ν} range allowed by the QRPA is excluded by the present measurement at the 90% confidence level. Our analysis reveals that predicted ξ_{31}^{2ν} values are sensitive to the quenching of NMEs and the competing contributions from low- and high-energy states in the intermediate nucleus. Because these aspects are also at play in neutrinoless ßß decay, ξ_{31}^{2ν} provides new insights toward reliable neutrinoless ßß NMEs.

3.
Phys Rev Lett ; 117(8): 082503, 2016 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-27588852

RESUMEN

We present an improved search for neutrinoless double-beta (0νßß) decay of ^{136}Xe in the KamLAND-Zen experiment. Owing to purification of the xenon-loaded liquid scintillator, we achieved a significant reduction of the ^{110m}Ag contaminant identified in previous searches. Combining the results from the first and second phase, we obtain a lower limit for the 0νßß decay half-life of T_{1/2}^{0ν}>1.07×10^{26} yr at 90% C.L., an almost sixfold improvement over previous limits. Using commonly adopted nuclear matrix element calculations, the corresponding upper limits on the effective Majorana neutrino mass are in the range 61-165 meV. For the most optimistic nuclear matrix elements, this limit reaches the bottom of the quasidegenerate neutrino mass region.

4.
Phys Rev Lett ; 105(15): 156601, 2010 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-21230921

RESUMEN

We report on the inversion of spin-dependent photocurrent via interface localized states formed at the interface of an Fe/n-AlGaAs/GaAs quantum well heterostructure by means of an optical spin orientation technique. A careful adjustment of the excitation photon energy, which is determined by a separate analysis of electroluminescence spectra under a spin injection condition, enables us to explore the spin-dependent characteristics of photoelectron transmission from the quantum well into Fe. The bias dependence of the spin-dependent photocurrent shows clear spikelike features at the voltage which is compatible with the formation of the interface localized resonant states in the Schottky depletion layer.

5.
J Investig Med ; 49(2): 184-90, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11288759

RESUMEN

BACKGROUND: We have developed a gene transfection system using laser beams. The principle of this procedure is that a small hole is made in a cell membrane by pulse laser irradiation, and a gene contained in a medium is transferred into the cytoplasm through the hole. This hole disappears immediately with the application of laser irradiation of the appropriate power. METHODS: A pulse-wave Nd:YAG laser with a wavelength of 355 nm was used to make a hole in a cell membrane. To trap a cell, a continuous-wave Nd:YAG laser with a wavelength of 1015 nm was used. Plasmids that encode the enhanced green fluorescent protein (EGFP) gene were contained in a medium and transferred to HuH-7 and NIH/3T3 cells with pulse laser irradiation. We evaluated transfection efficiency on the basis of the number of cells that expressed EGFP. Stimulatory protein 2 cells in suspension were fixed using a trapping laser and the neomycin-resistance gene was transfected by pulse laser irradiation. We examined cell proliferation in the selection medium. RESULTS: Cells that expressed EGFP were recognized in the group that was irradiated by pulse laser. No cells expressed EGFP without irradiation. Transfection efficiency was approximately 10% at a plasmid concentration of 10.0 microg/mL. At concentrations greater than 20 microg/mL, the transfection rate reached a plateau. We also successfully transfected neomycin-resistance genes to cells floating in suspension after fixation that was achieved with trapping laser irradiation. CONCLUSIONS: This method enables us to transfect targeted cells, ie, cells in suspension as well as attached cells, with a simple technique that does not involve harmful vectors. The present method is very useful for gene transfection in cellular biotechnology.


Asunto(s)
Transfección/métodos , Células 3T3 , Animales , Proteínas Fluorescentes Verdes , Proteínas Luminiscentes/genética , Ratones , Ratones Endogámicos BALB C , Plásmidos
6.
Nihon Jibiinkoka Gakkai Kaiho ; 99(6): 875-83, 1996 Jun.
Artículo en Japonés | MEDLINE | ID: mdl-8753073

RESUMEN

Despite the fact that vertigo has been one of the most frequent complaints encountered in daily practice in an ENT outpatient clinic, it is believed to be the most unwelcome subject for ENT physicians. The reasons are diverse; e.g., the understanding of vertigo is still a difficult task for most physicians and requires time-consuming multiple studies. However, answers to those questions, although speculated a posteriori, are yet to be substantiated. Therefore, we have analyzed the data obtained from multiple questionnaires that were addressed to ENT physicians practicing in Chiba Prefecture in November of 1993. However, those who work in publicly run hospitals were excluded from the study. The study included otorhinolaryngologists who were members of the Society of Otorhinolaryngology of Japan. We received filled questionnaire forms from 76 of 155 members (49%). The age ranged from 33 to 82 years (mean 55.8 years, 68 men and 8 women). From these questionnaires, it became apparent that physicians are not necessarily reluctant to see patients with vertigo. Instead, most ENT physicians appeared to be actively paying attention to this symptom and to be making efforts to approach its diagnosis and treatment. Although we are not certain if the data obtained here represent the majority of ENT physicians, the positive attitudes toward the patients with vertigo/dizziness would certainly encourage those of us who are interested in this particular symptom category.


Asunto(s)
Otolaringología , Vértigo/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Actitud del Personal de Salud , Femenino , Humanos , Japón , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios
7.
Tohoku J Exp Med ; 176(3): 173-80, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8553355

RESUMEN

Cystic adventitial disease (CAD) of the popliteal artery (PA) is rare but one of the well-recognized causes of intermittent claudication. Now more than 200 case reports are available in the world, but there are only 6 cases younger than 15 years old. In this paper, we report a case of 14-year-old boy with CAD of the PA found by intermittent claudication. On examination, the pulses were not palpable below the right popliteal artery, and the angiography demonstrated about 1.5 cm-long obstruction of the right PA. We operated a resection of a cyst with artery, and replaced the autovein graft (V. saphena magna). Cyst contained mucoid degeneration-like ganglion. Two weeks after operation, the angiography showed no stenotic lesion, and follow-up at 4 years showed no symptoms.


Asunto(s)
Arteriopatías Oclusivas/diagnóstico , Quistes/diagnóstico , Claudicación Intermitente/etiología , Arteria Poplítea/patología , Adolescente , Arteriopatías Oclusivas/complicaciones , Quistes/complicaciones , Humanos , Masculino
8.
Am J Chin Med ; 20(3-4): 313-7, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1471615

RESUMEN

Kuei-chih-fu-ling-wan (Keishi-bukuryo-gan; KBG), a traditional Chinese herbal remedy contains five components: bark of Cinnamomum cassia Bl. (Lauraceae), root of Paeonia lactiflora Pall. (Paeoniaceae), seed of Prunus persica Batsch. or P. persiba Batsch.var.davidiana Maxim. (Rosaceae), carpophores of Poria cocos Wolf. (Polyporaceae), and root bark of Paeonia suffruticosa Andr. (Paeoniaceae). This prescription has been frequently used in the treatment of gynecological disorders such as hypermenorrhea, dysmenorrhea and sterility. We previously reported that KBG might act as a LH-RH antagonist and a weak anti-estrogen on the uterine DNA synthesis in immature rats. In the present study, we investigated the effects of KBG on 110 premenopausal patients with uterine myomas. Clinical symptoms of hypermenorrhea and dysmenorrhea were improved in more than 90% of the cases with shrinking of uterine myomas in roughly 60% of the cases.


Asunto(s)
Medicamentos Herbarios Chinos/uso terapéutico , Leiomioma/tratamiento farmacológico , Neoplasias Uterinas/tratamiento farmacológico , Adulto , Antígenos de Carbohidratos Asociados a Tumores/sangre , Medicamentos Herbarios Chinos/administración & dosificación , Medicamentos Herbarios Chinos/farmacología , Estradiol/sangre , Femenino , Hormona Folículo Estimulante/sangre , Humanos , Leiomioma/sangre , Leiomioma/patología , Hormona Luteinizante/sangre , Persona de Mediana Edad , Prolactina/sangre , Neoplasias Uterinas/sangre , Neoplasias Uterinas/patología
9.
Nihon Jibiinkoka Gakkai Kaiho ; 93(12): 1991-8, 1990 Dec.
Artículo en Japonés | MEDLINE | ID: mdl-2292749

RESUMEN

A retrospective study of 44 patients who were involved in combination with chronic sinusitis and bronchiectasis provided better understanding of the etiology in the relationship between upper air ways tract and lower air way tract. The incidence of bronchictasis was found in 5%, 3 out of 60 cases with chronic sinusitis and that of chronic sinusitis in 45%, 44 out of 98 cases with idiopathic bronchiectasis. Both side involvements of the paranasal sinus and the lung were statistically high in sinobronchiectasis compared to chronic sinusitis or bronchiectasis involved alone. The past history of the patients with sinobronchiectasis showed high occurrence of bronchial asthma or allergic rhinitis, habitual angina of the throat, acute otitis media and pneumonia. A chest X. Ray evaluation of 70 patients with chronic sinusitis alone revealed relatively high incidence of abnormal fibro-nodular shadow in the lung compared to 70 patients without chronic sinusitis. It was thought that weakness of air-way tract to infection in the patients with sinobronchiectasis might play some role on break down of sino-bronchial syndrome, a combination disease of chronic sinusitis and chronic bronchitis.


Asunto(s)
Bronquiectasia/complicaciones , Sistema Respiratorio/fisiopatología , Sinusitis/complicaciones , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Bronquiectasia/fisiopatología , Bronquitis/etiología , Niño , Enfermedad Crónica , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Sinusitis/fisiopatología
14.
Rhinology ; 23(4): 327-32, 1985 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-4081531

RESUMEN

Radiological images of muco-pyoceles of the maxillary sinus often simulate those of malignancy. This presents a diagnostic dilemma for rhinologists. The authors studied the computed tomographic findings of 13 cases of muco-pyoceles of the maxillary sinus by obtaining two different images, one of the soft tissues and the other of the bony structures. The bony sinus walls are distended and thinned in many cases by long-standing intramural pressure. The most reliable finding in the diagnosis of muco-pyoceles is the smooth clear-cut margins of bone erosions occurring in the sinus walls.


Asunto(s)
Seno Maxilar/diagnóstico por imagen , Mucocele/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adulto , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Seno Maxilar/cirugía , Neoplasias del Seno Maxilar/diagnóstico por imagen , Persona de Mediana Edad , Factores de Tiempo
15.
Auris Nasus Larynx ; 12 Suppl 1: S211-3, 1985.
Artículo en Inglés | MEDLINE | ID: mdl-3835911

RESUMEN

Atelectasis of the middle ear cavity occurs in advanced chronic otitis media with effusion. Atelectasis with effusion may progress to atelectasis without effusion, and further possible complications include adhesive otitis, ossicular disruption, cholesteatoma, and sensorineural hearing loss. A classification is presented of the various sequelae of otitis media with effusion under the basic concept of the atelectatic ear because most of the sequelae observed had developed through the atelectatic ear. This classification depends on localization of the main pathology, i.e. the tympanic membrane, middle ear or inner ear.


Asunto(s)
Otitis Media con Derrame/patología , Membrana Timpánica/patología , Adolescente , Niño , Preescolar , Enfermedad Crónica , Clasificación , Femenino , Pérdida Auditiva Sensorineural/etiología , Humanos , Masculino
16.
Arch Otorhinolaryngol ; 239(1): 61-8, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6197964

RESUMEN

Keratin debris is a constant feature in middle-ear cholesteatoma. Keratin prepared from rat skin induced a foreign-body granuloma in the subcutaneous space in the rat. In vitro this granuloma produced high levels of bone-resorbing factors: prostaglandin E2, osteoclast-activating factor, and leucine aminopeptidase. In the in vivo study, keratin-induced granuloma in the rat middle ear caused partial resorption of the cochlear wall. Macrophages, fibroblasts, and osteoclastlike cells were found at bone-resorption areas. These cells appeared to be responsible for bone resorption through production of prostaglandin E2, osteoclast-activating factor, and proteases.


Asunto(s)
Resorción Ósea , Colesteatoma/metabolismo , Queratinas/metabolismo , Otitis Media/metabolismo , Animales , Resorción Ósea/efectos de los fármacos , Carragenina/farmacología , Colesteatoma/inducido químicamente , Dinoprostona , Técnicas In Vitro , Leucil Aminopeptidasa/metabolismo , Linfocinas/metabolismo , Masculino , Prostaglandinas E/metabolismo , Ratas
18.
Rhinology ; 20(4): 213-21, 1982 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7163740

RESUMEN

From a study of the roentgenographic findings of fronto-ethmoidal mucoceles and anatomical specimens of the paranasal sinuses the authors surmised that many of the fronto-ethmoidal mucocele probably originate either in one of the deeply seated supra-orbital frontal or ethmoidal recesses, or in an ethmoid cell whose ostium has been obstructed by postoperative, post-traumatic or post-inflammatory osteoneogenesis or cicatrization. When isolated, the cell with secreting mucosa would increase its cavity slowly but steadily, and eventually blocks the naso-frontal duct from without. The characteristic localization of the mucoceles, frequent erosion of the superomedial wall of the orbit with inferolateral displacement of the globe, our roentgenographic findings of a mucocele within the frontal sinus, pseudostratified columnar epithelium that lines the mucocele, occasional multilocularity, and the long interval, over ten years, that is required for the mucocele to show any symptoms in most instances would support this hypothesis.


Asunto(s)
Mucocele/diagnóstico por imagen , Enfermedades de los Senos Paranasales/diagnóstico por imagen , Adulto , Anciano , Senos Etmoidales , Femenino , Seno Frontal , Humanos , Masculino , Persona de Mediana Edad , Mucocele/patología , Enfermedades de los Senos Paranasales/patología , Radiografía , Factores de Tiempo
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