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1.
Phys Rev Lett ; 116(4): 041801, 2016 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-26871322

RESUMEN

We report on measurements of the decays of B¯ mesons into the semileptonic final states B¯â†’D^(*)π^(+)π^(-)ℓ^(-)ν¯, where D^(*) represents a D or D^(*) meson and ℓ^(-) is an electron or a muon. These measurements are based on 471×10^(6) BB ¯ pairs recorded with the BABAR detector at the SLAC asymmetric B factory PEP-II. We determine the branching fraction ratios R_{π^{+}π^{-}}^{(*)}=B(B[over ¯]→D^{(*)}π^{+}π^{-}ℓ^{-}ν[over ¯])/B(B[over ¯]→D^{(*)}ℓ^{-}ν[over ¯]) using events in which the second B meson is fully reconstructed. We find R_{π^{+}π^{-}}=0.067±0.010±0.008 and R_{π^{+}π^{-}}^{*}=0.019±0.005±0.004, where the first uncertainty is statistical and the second is systematic. Based on these results and assuming isospin invariance, we estimate that B[over ¯]→D^{(*)}ππℓ^{-}ν[over ¯] decays, where π denotes either a π^{±} and π^{0} meson, account for up to half the difference between the measured inclusive semileptonic branching fraction to charm hadrons and the corresponding sum of previously measured exclusive branching fractions.

2.
Phys Rev Lett ; 114(17): 171801, 2015 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-25978225

RESUMEN

We present a search for a neutral, long-lived particle L that is produced in e+ e- collisions and decays at a significant distance from the e+ e- interaction point into various flavor combinations of two oppositely charged tracks. The analysis uses an e+ e- data sample with a luminosity of 489.1 fb(-1) collected by the BABAR detector at the ϒ(4S), ϒ(3S), and ϒ(2S) resonances and just below the ϒ(4S). Fitting the two-track mass distribution in search of a signal peak, we do not observe a significant signal, and set 90% confidence level upper limits on the product of the L production cross section, branching fraction, and reconstruction efficiency for six possible two-body L decay modes as a function of the L mass. The efficiency is given for each final state as a function of the mass, lifetime, and transverse momentum of the candidate, allowing application of the upper limits to any production model. In addition, upper limits are provided on the branching fraction B(B→XsL), where Xs is a strange hadronic system.

3.
Phys Rev Lett ; 114(8): 081801, 2015 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-25768754

RESUMEN

We present a measurement of the asymmetry A_{CP} between same-sign inclusive dilepton samples ℓ^{+}ℓ^{+} and ℓ^{-}ℓ^{-} (ℓ=e, µ) from semileptonic B decays in ϒ(4S)→BB[over ¯] events, using the complete data set recorded by the BABAR experiment near the ϒ(4S) resonance, corresponding to 471×10^{6} BB[over ¯] pairs. The asymmetry A_{CP} allows comparison between the mixing probabilities P(B[over ¯]^{0}→B^{0}) and P(B^{0}→B[over ¯]^{0}), and therefore probes CP and T violation. The result, A_{CP}=[-3.9±3.5(stat)±1.9(syst)]×10^{-3}, is consistent with the standard model expectation.

4.
Phys Rev Lett ; 113(20): 201801, 2014 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-25432035

RESUMEN

Dark sectors charged under a new Abelian interaction have recently received much attention in the context of dark matter models. These models introduce a light new mediator, the so-called dark photon (A^{'}), connecting the dark sector to the standard model. We present a search for a dark photon in the reaction e^{+}e^{-}→γA^{'}, A^{'}→e^{+}e^{-}, µ^{+}µ^{-} using 514 fb^{-1} of data collected with the BABAR detector. We observe no statistically significant deviations from the standard model predictions, and we set 90% confidence level upper limits on the mixing strength between the photon and dark photon at the level of 10^{-4}-10^{-3} for dark photon masses in the range 0.02-10.2 GeV. We further constrain the range of the parameter space favored by interpretations of the discrepancy between the calculated and measured anomalous magnetic moment of the muon.

5.
Phys Rev Lett ; 111(10): 101802, 2013 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-25166652

RESUMEN

We present results of a search for CP violation in B0- B0 mixing with the BABAR detector. We select a sample of B0→D*- Xℓ+ ν decays with a partial reconstruction method and use kaon tagging to assess the flavor of the other B meson in the event. We determine the CP violating asymmetry ACP≡[N(B0B0)-N(B0B0)]/[N(B0B0)+N(B0B0)]=(0.06±0.17(-0.32)(+0.38))%, corresponding to ΔCP=1-|q/p|=(0.29±0.84(-1.61)(+1.88))×10(-3).

6.
Phys Rev Lett ; 111(11): 111801, 2013 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-24074072

RESUMEN

We measure the mass difference Δm0 between the D*(2010)+ and the D0 and the natural linewidth Γ of the transition D*(2010)+ → D0π+. The data were recorded with the BABAR detector at center-of-mass energies at and near the Υ(4S) resonance, and correspond to an integrated luminosity of approximately 477 fb(-1). The D0 is reconstructed in the decay modes D0 → K- π+ and D0 → K- π+ π- π+. For the decay mode D0 → K- π+ we obtain Γ = (83.4±1.7±1.5) keV and Δm0 = (145425.6±0.6±1.7) keV, [corrected] where the quoted errors are statistical and systematic, respectively. For the D0 → K- π+ π- π+ mode we obtain Γ = (83.2±1.5±2.6) keV and Δm0 = (145426.6±0.5±1.9) keV. [corrected] The combined measurements yield Γ = (83.3±1.2±1.4) keV and Δm0 = (145425.9±0.4±1.7) keV; the width is a factor of approximately 12 times more precise than the previous value, while the mass difference is a factor of approximately 6 times more precise.

7.
Am J Psychiatry ; 133(9): 995-1007, 1976 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-786048

RESUMEN

There has been a recent and rapid increase in research literature pertaining to women; this revolution in women's studies may be currently unequaled in any other field related to psychiatry. In this first part of a two-part article the author briefly discusses the social and intellectual contexts of research in this area. She reviews recent research on gender differences in behavior and on women's sexual and reproductive lives, including various aspects of the menstrual cycle, menopause, diseases of the reproductive organs, coitus, rape, childbirth, lactation, and fertility control. The second part will cover research on women in families, communities, work, and psychotherapy; and it will attempt to assess limitations of present knowledge and the anticipated directions and impact of future research.


PIP: The social and intellectual contexts of research in the area of the psychology of women are discussed. Major findings in aspects of gender differences and sexual and reproductive live are reviewed. The discussion on sexual and reproductive life includes the significance of aspects of the menstrual cycle, menopause, diseases of the reproductive organs, coitus, rape, childbirth, lactation, and fertility control. Today the norm of controlling one's own fertility is experienced as new, and pregnancy is felt to be a matter of choice. However, no contraceptive method except sterilization is 100% effective and many have medical hazards. The safest methods for women are the diaphragm and the condom with back-up abortion, but these methods are psychologically less acceptable. There is a need for research on the psychology of family planning outside of the nuclear family. Data support the conclusion that abortion is safer than normal birth.


Asunto(s)
Mujeres , Coito , Servicios de Planificación Familiar , Femenino , Identidad de Género , Enfermedades de los Genitales Femeninos , Humanos , Trabajo de Parto , Lactancia , Menopausia , Menstruación , Embarazo , Psicología , Violación , Reproducción , Investigación , Conducta Sexual
8.
Am J Psychiatry ; 133(10): 1111-23, 1976 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-788527

RESUMEN

In the first part of this overview the author reviewed research on gender differences in behavior and women's sexual and reproductive lives, and discussed the social and intellectual context of the recent knowledge explosion in women's studies. In this second part she reviews recent research on selected aspects of the social psychology of women's lives. Highlighted themes include women in relationship to family structure and child rearing, work and achievement motivation, and implications for the psychiatric treatment of women that can be drawn from the psychotherapy research literature. She briefly assesses the possible impact of research in these areas on psychiatric theory and practice.


Asunto(s)
Empleo , Familia , Psicoterapia , Mujeres , Logro , Crianza del Niño , Derechos Civiles , Depresión/terapia , Predicción , Identidad de Género , Homosexualidad , Humanos , Relaciones Interpersonales , Trastornos Mentales/etiología , Psicología , Investigación , Esquizofrenia/terapia , Estrés Psicológico
9.
Head Neck Surg ; 8(4): 287-95, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3744857

RESUMEN

The literature describes numerous techniques for reconstruction of the subglottic larynx. The use of rigid bone grafts or flaps has been associated with problems because the rigid bone cannot conform to the defect and form an airtight seal. We have performed subglottic reconstruction using the sternocleidomastoid myoperiosteal flap with very optimistic results on long-term follow up. The sternocleidomastoid myoperiosteal flap is a relatively simple procedure that can be used for a large variety of defects. The pliable periosteal flap used for closing the defect can be molded over a stent to form an airtight seal. We have demonstrated bone formation in the periosteum which is crucial to the stability of the airway and long-term success of the procedure. The sternocleidomastoid myoperiosteal flap yields a pliable, durable tissue capable of airtight closure and a tension-free suture line. This technique will make the closure of subglottic defects a much more practical task.


Asunto(s)
Cartílagos Laríngeos/cirugía , Colgajos Quirúrgicos , Estenosis Traqueal/cirugía , Anciano , Animales , Perros , Femenino , Humanos , Persona de Mediana Edad , Complicaciones Posoperatorias/cirugía , Estenosis Traqueal/etiología , Traqueotomía/efectos adversos
10.
Head Neck Surg ; 7(1): 22-7, 1984 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6490382

RESUMEN

Data from 131 consecutive patients with operable stage III or IV (American Joint Committee) supraglottic carcinoma were analyzed. Based on existing treatment policies at the time of presentation, patients received either preoperative radiation therapy (RT) (48 patients), surgery alone (42 patients), or postoperative RT (41 patients). Preoperative RT dose levels were either 2,000 rad in five fractions (33 patients) or 5,000 rad in 25 fractions (15 patients). Postoperative RT dosages were 5,000 to 6,000 rad in 6 to 6 1/2 weeks. Surgical procedures included either subtotal or total laryngectomy and radical neck dissection. Tumor control was achieved in 21 of 42 patients (50%) treated with surgery alone, 23 of 48 patients (48%) treated with preoperative RT, and 29 of 41 patients (71%) treated with postoperative RT (P = 0.005). The actuarial, recurrence-free survival at 5 years was 36% and 35%, respectively, in the surgery alone or preoperative RT groups as compared to 55% in postoperatively irradiated patients. The authors conclude that advanced but resectable supraglottic carcinomas may be best treated with surgery followed by RT, rather than with surgery alone or with combined preoperative RT and surgery.


Asunto(s)
Carcinoma de Células Escamosas/terapia , Glotis , Neoplasias Laríngeas/terapia , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/cirugía , Terapia Combinada , Humanos , Neoplasias Laríngeas/radioterapia , Neoplasias Laríngeas/cirugía , Recurrencia Local de Neoplasia , Complicaciones Posoperatorias , Pronóstico , Traumatismos por Radiación/etiología
11.
Psychiatr Clin North Am ; 12(1): 1-24, 1989 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2652102

RESUMEN

Throughout life, some psychological issues facing women are shared with men, and some are unique to women. This article compares the traditional life cycle perspective with the complementary perspective of different lines of development that characterize women's lives. Traditionally, there was a concept, especially of the woman's life cycle, linking growth and reproduction to expected work, social status, and sources of self-esteem. Today, there is no single life cycle for women, but rather a number of predictable areas of growth and development. The article will explore the biologic-reproductive life cycle, the family-marital life cycle, and the educational-vocational life cycle, from before birth to old age. It will also review psychological problems most common at each stage, and it will discuss how societal changes in expectations of women may be changing women's growth and development today.


Asunto(s)
Envejecimiento/psicología , Identidad de Género , Identificación Psicológica , Acontecimientos que Cambian la Vida , Desarrollo de la Personalidad , Femenino , Humanos
12.
Laryngoscope ; 111(1): 9-14, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11192906

RESUMEN

OBJECTIVES/HYPOTHESIS: Two of the most common causes of olfactory loss include upper respiratory infection (URI) and nasal or sinus disease. The etiology of most URI-related losses is thought to be viral and, as yet, there is no available treatment. In contrast, nasal or sinus disease produces an obstructive or conductive loss that often responds dramatically to appropriate therapy. Therefore, the distinction is important but in many cases may be difficult because such patients often present with no other nasal symptoms, and routine physical findings may be nonspecific. The purpose of this report is to characterize those aspects of the history and physical examination that will help to substantiate the diagnosis of a conductive olfactory loss. STUDY DESIGN: A retrospective, nonrandomized study of consecutive patients presenting with a primary complaint of olfactory loss. METHODS: This study reviewed 428 patients seen at a university-based taste and smell clinic from July 1987 through December 1998. Of this total, 60 patients were determined to have a conductive olfactory loss. All patients were referred specifically because of a primary chemosensory complaint. The University of Pennsylvania Smell Identification Test (UPSIT; Sensonics, Inc., Haddon Heights, NJ) was administered in all cases. RESULTS: The most commonly diagnosed etiologies of olfactory loss were head injury (18%), upper respiratory infection (18%), and nasal or sinus disease (14%). Of the 60 patients with a conductive loss, only 30% complained of nasal obstruction, whereas 58% described a history of chronic sinusitis. Only 45% reported that their olfactory loss at times seemed to fluctuate in severity. Anterior rhinoscopy failed to diagnose pathology in 51% of cases, whereas nasal endoscopy missed the diagnosis in 9%. Systemic steroids elicited a temporary reversal of conductive olfactory loss in 83% of patients who received them, offering a useful diagnostic maneuver, whereas topical steroids did so in only 25%. CONCLUSIONS: The etiology for olfactory loss can in many cases be difficult to determine, but it is important to establish prognosis and to predict response to therapy. Diagnosis requires a thorough history, appropriate chemosensory testing, and a physical examination that should include nasal endoscopy. A trial of systemic steroids may serve to verify that the loss is indeed conductive.


Asunto(s)
Trastornos del Olfato/diagnóstico , Corticoesteroides/administración & dosificación , Corticoesteroides/uso terapéutico , Enfermedad Crónica , Traumatismos Craneocerebrales/complicaciones , Traumatismos Craneocerebrales/diagnóstico , Endoscopía , Femenino , Humanos , Masculino , Anamnesis , Persona de Mediana Edad , Obstrucción Nasal/complicaciones , Obstrucción Nasal/diagnóstico , Pólipos Nasales/complicaciones , Pólipos Nasales/diagnóstico , Enfermedades Nasales/complicaciones , Enfermedades Nasales/diagnóstico , Trastornos del Olfato/etiología , Enfermedades de los Senos Paranasales/complicaciones , Enfermedades de los Senos Paranasales/diagnóstico , Planificación de Atención al Paciente , Examen Físico , Pronóstico , Infecciones del Sistema Respiratorio/complicaciones , Infecciones del Sistema Respiratorio/diagnóstico , Estudios Retrospectivos , Rinitis/complicaciones , Rinitis/diagnóstico , Sinusitis/complicaciones , Sinusitis/diagnóstico , Olfato/fisiología , Estadísticas no Paramétricas , Gusto/fisiología
13.
Laryngoscope ; 105(9 Pt 1): 919-23, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7666725

RESUMEN

Within the upper aerodigestive tract, histoplasmosis often mimics carcinoma, making prompt and accurate diagnosis imperative. More severe and potentially lethal infections with Histoplasma capsulatum are now being seen as the numbers of patients at the extremes of age, as well as those with compromised immune systems, increase. We reviewed the cases of 115 hospitalized patients with disseminated histoplasmosis. Of these, 9 patients were identified with otolaryngologic manifestations: 4 were infected with human immunodeficiency virus (HIV), 1 was diabetic, and 3 were renal transplant patients. Sites of involvement included the larynx (in 2 cases) and the oral cavity and oral pharynx (in 7 cases). Eight of the 9 patients had a positive biopsy result; the other, a positive culture. Treatment with amphotericin B was generally effective, while the use of newer azole anti-fungal agents were less effective. As the number of immunocompromised patients continues to increase in modern clinical practice, histoplasmosis will undoubtedly be encountered more frequently in the head and neck area.


Asunto(s)
Histoplasmosis , Enfermedades de la Laringe/microbiología , Enfermedades Estomatognáticas/microbiología , Anfotericina B/uso terapéutico , Infecciones por VIH/complicaciones , Histoplasmosis/diagnóstico , Histoplasmosis/tratamiento farmacológico , Humanos , Itraconazol/uso terapéutico , Enfermedades de la Laringe/diagnóstico , Neoplasias Laríngeas/diagnóstico , Laringoscopía , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Enfermedades Estomatognáticas/complicaciones , Enfermedades Estomatognáticas/tratamiento farmacológico , Resultado del Tratamiento
14.
Arch Otolaryngol Head Neck Surg ; 121(10): 1183-7, 1995 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7546588

RESUMEN

OBJECTIVE: To determine the extent to which olfactory function can improve after loss induced by head trauma or a previous upper respiratory tract infection (URI) and the time for this improvement for more effective patient counseling. DESIGN: Patients initially evaluated at the University of Cincinnati (Ohio) Taste and Smell Center were reevaluated for olfactory loss with the University of Pennsylvania (Philadelphia) Smell Identification Test 1 to 5 years after initial testing. Changes in score on this test were used to indicate improvement in sensory function. Subjective information on olfactory ability and olfactory symptoms was also collected. SETTING: University-based tertiary care center. PATIENTS AND OTHER PARTICIPANTS: Forty-one patients with olfactory loss induced by head trauma (20) or previous URI (21). RESULTS: Seven (35%) of 20 patients with head trauma improved on the smell test by 4 points or more. Fourteen of 21 (67%) patients with a previous URI had improved scores of this magnitude or more. A statistically significant correlation was noted between the amounts of improvement and length of follow-up for URI patients. Thirteen of these patients also reported improved olfactory function. CONCLUSION: These findings for patients with head trauma are consistent with other reports of recovery of (or improvement in) olfactory function after trauma-induced loss. For patients with previous URI, these data indicate that improvement in olfactory function occurs, but the improvement may take several years.


Asunto(s)
Traumatismos Craneocerebrales/complicaciones , Trastornos del Olfato/etiología , Infecciones del Sistema Respiratorio/complicaciones , Adulto , Consejo , Femenino , Estudios de Seguimiento , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Odorantes , Trastornos del Olfato/fisiopatología , Remisión Espontánea , Reproducibilidad de los Resultados , Olfato/fisiología
15.
Arch Otolaryngol Head Neck Surg ; 118(7): 731-8, 1992 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1627295

RESUMEN

Thirty-six mucosal specimens were obtained with a biopsy instrument from the upper nasal septum of 12 human autopsy cases before the en bloc removal of the entire olfactory area. Examination of these 36 specimens with transmission electron microscopy demonstrated olfactory epithelium in only 17. A significant negative correlation (r = -.728) was noted between the age of the subject and the probability of obtaining olfactory epithelium, supporting the idea that the olfactory mucosa is gradually replaced by respiratory epithelium with aging. Using the en bloc specimens, the distribution of olfactory epithelium was reconstructed from light microscopic examination of silver-stained sections. Multiple patches of respiratory epithelium were observed over the upper portion of the nasal septum and superior turbinates, ie, the presumptive olfactory area. On transmission electron microscopic examination, frequent respiratory metaplasia was also suggested. Within the area of respiratory metaplasia, supporting cell-like and microvillar cell-like structures often were found; these structures may be remnants of olfactory epithelium. The sampling of olfactory tissue with a biopsy procedure is hampered by the irregular and patchy distribution of olfactory epithelium. The invasion of respiratory epithelial patches into the olfactory mucosa seems to be characteristic of the human olfactory epithelium and may increase as a function of age. Thus, conclusions about the structure of the olfactory mucosa in an individual patient must be based on several tissue samples.


Asunto(s)
Envejecimiento/fisiología , Mucosa Olfatoria/citología , Adulto , Anciano , Anciano de 80 o más Años , Autopsia , Células Epiteliales , Humanos , Metaplasia , Microscopía Electrónica , Persona de Mediana Edad , Sistema Respiratorio/citología
16.
Otolaryngol Clin North Am ; 34(1): 227-41, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11344075

RESUMEN

Frontal headache is a common complaint associated with frontal sinus disease and is often the only complaint. It is also a common location for headache pain in association with other primary and secondary headache disorders. Therefore, the clinician needs to have a thorough understanding of the differential diagnosis of frontal headache pain. This article reviews the causes of frontal pain in association with nasal and sinus pathology and also discusses other headache disorders that can present with similar symptoms.


Asunto(s)
Sinusitis Frontal/complicaciones , Sinusitis Frontal/fisiopatología , Cefalea/etiología , Adolescente , Diagnóstico Diferencial , Femenino , Sinusitis Frontal/diagnóstico , Cefalea/clasificación , Cefalea/diagnóstico , Humanos , Tomografía Computarizada por Rayos X
17.
Otolaryngol Clin North Am ; 25(4): 817-35, 1992 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1470441

RESUMEN

Chemosensory disorders have been receiving increasing clinical attention but remain a difficult diagnostic problem. With the development of several well-standardized testing methods, taste or smell loss can now be verified, and this has added to knowledge concerning the common causes of dysfunction. Diagnosis typically rests upon the history and physical examination, but, except in the case of obstructive nasal and sinus pathologic conditions, therapy usually remains elusive.


Asunto(s)
Trastornos del Olfato , Trastornos del Gusto , Atención Ambulatoria , Traumatismos Craneocerebrales/complicaciones , Humanos , Trastornos del Olfato/diagnóstico , Trastornos del Olfato/etiología , Trastornos del Olfato/terapia , Pronóstico , Enfermedades Respiratorias/complicaciones , Células Receptoras Sensoriales/anatomía & histología , Células Receptoras Sensoriales/fisiología , Trastornos del Gusto/diagnóstico , Trastornos del Gusto/etiología , Trastornos del Gusto/terapia
18.
Acta Cytol ; 44(6): 1073-6, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11127737

RESUMEN

BACKGROUND: Fine needle aspiration (FNA) biopsy is reliably used to classify most conditions involving the salivary glands. It is useful for establishing, or at least suggesting, the diagnosis in unusual cases or narrowing the differential diagnosis. CASE: A 25-year-old male presented with a slowly enlarging mass of the left parotid. FNA biopsy of the parotid gland was performed, and a diagnosis of papillary-cystic variant of acinic cell carcinoma was suggested. The patient underwent incomplete resection of the lesion, which was interpreted as acinic cell carcinoma. CONCLUSION: Papillary-cystic variant of acinic cell carcinoma is rarely seen, especially in young people. FNA biopsy is a useful diagnostic procedure that can help diagnose this relatively uncommon type of salivary gland neoplasm and guide its management.


Asunto(s)
Carcinoma de Células Acinares/patología , Neoplasias de las Glándulas Salivales/patología , Adulto , Biopsia con Aguja , Carcinoma Papilar/patología , Cistadenocarcinoma/patología , Humanos , Masculino
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