RESUMEN
Betel quid chewing is a major cause of oral cancers in Asia. Practitioners must be able to recognize premalignant lesions. Cessation of betel quid use and preventive treatment must be recommended. Primary prevention will be difficult because of the traditional nature and commercial importance of this old habit.
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Areca/efectos adversos , Carcinoma de Células Escamosas/etiología , Masticación , Neoplasias de la Boca/etiología , Anciano , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/terapia , Quimioterapia Adyuvante , Resultado Fatal , Femenino , Humanos , Neoplasias de la Boca/diagnóstico , Neoplasias de la Boca/terapia , Radioterapia Adyuvante , Trastornos Relacionados con Sustancias/complicacionesRESUMEN
A comprehensive review of physics at an [Formula: see text] linear collider in the energy range of [Formula: see text] GeV-3 TeV is presented in view of recent and expected LHC results, experiments from low-energy as well as astroparticle physics. The report focusses in particular on Higgs-boson, top-quark and electroweak precision physics, but also discusses several models of beyond the standard model physics such as supersymmetry, little Higgs models and extra gauge bosons. The connection to cosmology has been analysed as well.
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To determine the importance of usual risk factors of coronary artery disease (CAD) in patients with coronary artery spasm, 40 patients with vasospastic angina (VA), normal or nearly normal coronary arteries and without previous myocardial infarction were compared with 2 control groups of 40 patients each, matched for age and sex: 1 group with CAD and 1 without heart disease. Ninety percent of patients with VA were cigarette smokers and 70% were heavy smokers (more than 20 cigarettes daily), compared with 53% and 33% in patients with CAD (p less than 0.001) and 30% and 15% in those without heart disease (p less than 0.001). Except for cigarette smoking, the risk factor profile of patients with VA appeared more like the profile of patients without heart disease than that of patients with CAD. The results suggest that cigarette smoking may play a role in CAD independent of atherosclerosis and possibly favoring coronary artery spasm.
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Enfermedad Coronaria/etiología , Vasoespasmo Coronario/etiología , Fumar , Adulto , Factores de Edad , Anciano , Colesterol/sangre , Enfermedad Coronaria/patología , Vasoespasmo Coronario/patología , Vasos Coronarios/patología , Complicaciones de la Diabetes , Femenino , Humanos , Hipertensión/complicaciones , Masculino , Persona de Mediana Edad , Riesgo , Factores SexualesRESUMEN
The E815 (NuTeV) neutrino experiment has performed a search for a 33. 9 MeV/c(2) weakly interacting neutral particle produced in pion decay. Such a particle may be responsible for an anomaly in the timing distribution of neutrino interactions in the KARMEN experiment. E815 has searched for this particle's decays in an instrumented decay region; no evidence for this particle was found. The search is sensitive to pion branching ratios as low as 10(-13).
RESUMEN
An epidemiological and clinical study was carried out on 31 patients with spasm of normal coronary arteries. The series comprised 24 males and 7 females aged 30 to 68 years (mean age: 48 years) with isolated resting chest pain (61 p. 100) or with resting and effort chest pains (39 p. 100). Their cardiovascular risk factors were compared to 735 unselected patients with coronary insufficiency undergoing coronary coronary angiography. Abnormalities of lipid metabolism (45 p. 100) and obesity (14 p. 100) were less common but there was a higher incidence of smoking (74 p. 100 compared to 48 p. 100). Sixteen patients had a psychological test: repressed aggressivity and severe anxiety were found in all patients, a state of separation coincided wtih the onset of the illness in 10 of the 16 patients. On admission, 13 patients presented with attacks of Prinzmetal variant angina, with myocardial infarction in 2 cases. Eighteen patients had non-invalidating angina with sporadic attacks. Coronary angiography was normal in 8 patients and showed lesions with less than 50 p. 100 narrowing in the other 23 patients. Mitral valve prolapse was found on left ventriculography in four patients. Exercise electrocardiography was positive in 7 out of 20 patients, and notably in those who had not had effort angina. All patients were treated with calcium antagonist drugs (25 Nifedipine, 6 Diltiazem), the efficacity of which was tested in 20 patients with a control ergometrine test. Thirty patients were followed up for 6 to 46 months (mean: 15 months). The exercise stress tests were repeated in the 7 patients with positive results before treatment and the results were negative in all cases. Twenty three patients were completely pain free or significantly improved, although 25 p. 100 of control tests remained positive (4/16). Six patients continued to have as much chest pain, and three had positive control tests. One patient with a negative control test developed acute myocardial infarction six months later in the territory of the spasm: during hospitalisation the ergometrine test became positive again.
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Angiografía Coronaria , Vasoespasmo Coronario/etiología , Adulto , Anciano , Vasoespasmo Coronario/diagnóstico , Vasoespasmo Coronario/tratamiento farmacológico , Vasos Coronarios/patología , Prueba de Esfuerzo , Femenino , Estudios de Seguimiento , Ventrículos Cardíacos/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/etiología , FumarRESUMEN
Arterial blood gases (pH, pO2, p CO2) were studied in 100 patients with documented pulmonary embolism (Group A), confirmed by pulmonary angiography (n = 51) or scintigraphy ( n = 49). The pO2 ranged from 32 to 97 mm Hg (average 60,5 +/- 13 mm Hg). Hypoxaemia was found in 97 cases and would therefore seem to be a reliable sign of pulmonary embolism. In the three cases in which it was absent, the embolism was small. Hypoxaemia was associated with hypocapnia and alkalosis in 91 cases. However, hypoxaemia was not a specific finding; it was also present in 49 patients with suspected pulmonary embolism (Group B) in whom the diagnosis was excluded by pulmonary angiography or scintigraphy. A previous history of cardiovascular disease was found in 37 patients (76%) in this group: of the 12 remaining patients, 6 were heavy smokers and 4 were significantly obese. No correlation was found between the degree of hypoxaemia and the extent of amputation of the vascular bed on pulmonary angiography or scintigraphy. Nevertheless, a pO2 of under 50 mm Hg was always associated with a severe embolism with amputation of over 40% of the pulmonary vascular bed. A significant correlation was found between the severity of hypoxaemia and the degree of cyanosis (p less than 0,05) and ECG changes (p less than 0,01). The average pO2 was 59 +/- 12 mm Hg in patients with cardiovascular disease ( n = 21) and 55 +/- 11 mm Hg with known pulmonary disease ( n = 6). A higher average pO2 was found when these conditions were absent (61,5 +/- 13 mmHg). The difference was not statistically significant unless previous cardiac and pulmonary disease were associated (pO2 = 51 +/- 14 mm Hg, p less than 0,05).
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Análisis de los Gases de la Sangre , Embolia Pulmonar/sangre , Enfermedad Aguda , Anciano , Arterias , Femenino , Humanos , Concentración de Iones de Hidrógeno , Masculino , Persona de Mediana Edad , Pronóstico , Embolia Pulmonar/diagnósticoRESUMEN
The aim of this study was to compare the medium-term results of medical therapy and aortocoronary bypass surgery in 87 patients selected on the following criteria: Clinical: unstable angina, defined as effort and/or resting angina appearing for the first time or increasing in severity within the previous 3 months, the last attack of chest pain occurring less than 8 days before admission to the Coronary Care Unit, with no signs of myocardial infarction before hospital admission and at coronary angiography. Coronary angiography: proximal isolated left anterior descending artery stenosis (greater than 70%). Thirty five patients were treated medically and 52 underwent coronary bypass surgery on the LAD artery: the results were compared at 18 and 24 months. Six patients were lost to follow-up, 2 from the medical group; the other 33 patients comprised group A. Four surgical patients were lost to follow-up, the other 48 patients comprised group B. The two groups had comparable clinical and epidemiological features. They differed in the incidence of hypertension which was more common in group A (p less than 0.01), in the better quality of the distal LAD artery in group B (p less than 0.01), and in the coexistence of less than 50% stenosis on the right coronary and left circumflex arteries which was commoner in group A (p less than 0.05). The mean follow-up period was comparable in the two groups (group A: 20.5 +/- 4.6 months; group B: 19.8 +/- 5.5 months).(ABSTRACT TRUNCATED AT 250 WORDS)
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Angina de Pecho/terapia , Angina Inestable/terapia , Angiografía Coronaria , Puente de Arteria Coronaria , Antagonistas Adrenérgicos beta/uso terapéutico , Angina Inestable/etiología , Anticoagulantes/uso terapéutico , Bloqueadores de los Canales de Calcio/uso terapéutico , Vasos Coronarios/patología , Quimioterapia Combinada , Electrocardiografía , Humanos , Nitratos/uso terapéutico , Pronóstico , Vasodilatadores/uso terapéuticoRESUMEN
To evaluate the epidemiological features of human hydatidosis during the first two decades of life, and to assess whether it exists autochthonously in Catalonia, we analysed the patients younger than 20 years who had been diagnosed and/or treated between 1977 and 1985 in 46 hospitals (representing 95% of the hospital beds in Catalonia where surgical therapy for hydatid disease is available). Ninety-five cases were detected in 87 patients. The mean yearly incidence rate was 0.53/100,000. In 81 patients hydatidosis was diagnosed for the first time in their lives, in 11 for the second time, and in three for the third time. Among the first there was a predominance of exclusively pulmonary cysts (41.9%) over those with exclusively hepatic localization (32%) and with simultaneous hepatic and pulmonary localization (13%). Surgical operations were undertaken in 112 instances, with a mortality rate of 2.2%. It was estimated, by the actuarial method, that the likelihood of a second diagnosis of hydatid disease after the surgical removal of all the cysts found at the time of the first diagnosis was 4.2% two years after the last operation, 9.5% after four years, and 24.6% after 7 years. The incidence rate in the immigrant population was 3.03 times higher than the recorded one for Catalonia. Sixteen patients born in Catalonia reported not to have ever traveled out of it; this information was confirmed by the separate parents report. This would confirm the occurrence of autochthonous hydatid disease.
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Equinococosis/epidemiología , Adolescente , Adulto , Niño , Preescolar , Equinococosis/cirugía , Equinococosis Hepática/epidemiología , Equinococosis Hepática/cirugía , Equinococosis Pulmonar/epidemiología , Equinococosis Pulmonar/cirugía , Femenino , Hepatectomía , Humanos , Masculino , Neumonectomía , EspañaAsunto(s)
Arritmias Cardíacas/inducido químicamente , Digitoxina/envenenamiento , Digoxina/inmunología , Fragmentos Fab de Inmunoglobulinas , Adulto , Arritmias Cardíacas/terapia , Reacciones Cruzadas , Digitoxina/análisis , Femenino , Bloqueo Cardíaco/terapia , Humanos , Fragmentos Fab de Inmunoglobulinas/análisis , Potasio/sangre , Intento de Suicidio , Fibrilación Ventricular/terapiaAsunto(s)
Eritema Nudoso/complicaciones , Complicaciones del Embarazo/diagnóstico , Enfermedades Cutáneas Vesiculoampollosas/complicaciones , Adulto , Eritema Nudoso/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neutrófilos , Embarazo , Enfermedades Cutáneas Vesiculoampollosas/diagnóstico , SíndromeRESUMEN
We present a LIGO search for short-duration gravitational waves (GWs) associated with soft gamma ray repeater (SGR) bursts. This is the first search sensitive to neutron star f modes, usually considered the most efficient GW emitting modes. We find no evidence of GWs associated with any SGR burst in a sample consisting of the 27 Dec. 2004 giant flare from SGR 1806-20 and 190 lesser events from SGR 1806-20 and SGR 1900+14. The unprecedented sensitivity of the detectors allows us to set the most stringent limits on transient GW amplitudes published to date. We find upper limit estimates on the model-dependent isotropic GW emission energies (at a nominal distance of 10 kpc) between 3x10;{45} and 9x10;{52} erg depending on waveform type, detector antenna factors and noise characteristics at the time of the burst. These upper limits are within the theoretically predicted range of some SGR models.
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We present a new measurement of the difference between the nucleon strange and antistrange quark distributions from dimuon events recorded by the NuTeV experiment at Fermilab. This analysis is the first to use a complete next to leading order QCD description of charm production from neutrino scattering. Dimuon events in neutrino deep inelastic scattering allow direct and independent study of the strange and antistrange content of the nucleon. We find a positive strange asymmetry with a significance of 1.6sigma. We also report a new measurement of the charm mass.
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We place direct upper limits on the amplitude of gravitational waves from 28 isolated radio pulsars by a coherent multidetector analysis of the data collected during the second science run of the LIGO interferometric detectors. These are the first direct upper limits for 26 of the 28 pulsars. We use coordinated radio observations for the first time to build radio-guided phase templates for the expected gravitational-wave signals. The unprecedented sensitivity of the detectors allows us to set strain upper limits as low as a few times 10(-24). These strain limits translate into limits on the equatorial ellipticities of the pulsars, which are smaller than 10(-5) for the four closest pulsars.
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The Laser Interferometer Gravitational-Wave Observatory has performed a third science run with much improved sensitivities of all three interferometers. We present an analysis of approximately 200 hours of data acquired during this run, used to search for a stochastic background of gravitational radiation. We place upper bounds on the energy density stored as gravitational radiation for three different spectral power laws. For the flat spectrum, our limit of omega0 < 8.4 x 10(-4) in the 69-156 Hz band is approximately 10(5) times lower than the previous result in this frequency range.
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Exploiting the manipulation of the SLAC Linear Collider electron-beam polarization, we present precise direct measurements of the parity-violation parameters A(c) and A(b) in the Z-boson-c-quark and Z-boson-b-quark coupling. Quark-antiquark discrimination is accomplished via a unique algorithm that takes advantage of the precise SLAC Large Detector charge coupled device vertex detector, employing the net charge of displaced vertices as well as the charge of kaons that emanate from those vertices. From the 1996-1998 sample of 400 000 Z decays, produced with an average beam polarization of 73.4%, we find A(c)=0.673+/-0.029(stat)+/-0.023(syst) and A(b)=0.919+/-0.018(stat)+/-0.017(syst).
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Noncarious tooth lesions (NCTL) are frequent findings in contemporary dental practices. Unlike other dental and periodontal diseases, NCTL have not been studied in an anthropological context. The purpose of the present study was to compare the prevalence of NCTL in three archaeological samples from the Copper Age and Middle Ages and in subjects examined in three dental practices. Both archaeological samples and dental-practice subjects were from southern France. In the archaeological sample group, no NCTL were detected in 3,927 teeth from 259 individuals. In the dental-practice group, prevalence rates were in agreement with current epidemiological data. Our data also suggest that prevalence of NCTL increases with age and is higher in females. Premolars were the most affected tooth type. Occurrence of NCTL has long been attributed to toothbrushing and to erosion by intrinsic and extrinsic acids. More recently, occlusal stress associated with tooth flexure has been implicated. The reasons underlying the total absence of NCTL in archaeological samples are discussed. The most likely explanations involve differences in lifestyle, diet, and dental condition.
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Fósiles , Cuello del Diente/patología , Enfermedades Dentales/patología , Adolescente , Adulto , Antropología Física , Niño , Dieta , Femenino , Francia , Humanos , Estilo de Vida , Masculino , Masticación , Prevalencia , Estrés Mecánico , Enfermedades Dentales/epidemiologíaRESUMEN
The clinical course of 48 consecutive patients with vasospastic angina and minor coronary atherosclerosis (no stenoses greater than 50%) was analyzed during an average follow-up period of 47 months. The study group consisted of 37 men and 11 women. Patients were treated with usual doses of calcium antagonists. One patient died (2%) and three had myocardial infarctions (6%). Seventy-one percent were asymptomatic or had infrequent angina; 13% had recurrences but had periods of remission lasting at least 10 months. Only 16% had persistent angina. None of the clinical or angiographic findings at the time of diagnosis were predictive of myocardial infarction or death, and they could not separate angina-free patients from those with recurrences. Thus, vasospastic angina without fixed coronary narrowing has a good prognosis despite the possibility of recurrences. However, there is a slight risk of myocardial infarction and death. This fact should be considered if there are plans to discontinue treatment.
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Angina Pectoris Variable/tratamiento farmacológico , Arteriosclerosis/complicaciones , Enfermedad Coronaria/complicaciones , Adulto , Angina Pectoris Variable/complicaciones , Angina Pectoris Variable/diagnóstico por imagen , Bloqueadores de los Canales de Calcio/uso terapéutico , Angiografía Coronaria , Muerte Súbita , Ergonovina , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Recurrencia , Factores de TiempoRESUMEN
BACKGROUND: The homeless are at very high risk of suffering tuberculosis (TB). The aims of this study were to determine the prevalence and risk factors for tuberculosis infection and disease among the homeless in Barcelona and to evaluate the roles of case finding and contact investigation. METHODS: Observational prevalence study carried out between 1997 and 1998. PARTICIPANTS: 447 homeless patients (394 men and 53 women) were evaluated before admission to shelters and free-meal services. At the same time, 48 co-residents with smear-positive TB patients in 2 long-term shelters were evaluated too. A chest X-ray and Tuberculin Skin Test were performed on all subjects. Sputum smears were processed by the Ziehl-Neelsen and Löwenstein-Jensen procedures in patients with radiographic findings consistent with pulmonary TB. RESULTS: Of the 447 homeless examined, 335 (75%) were infected with Mycobacterium tuberculosis. Active pulmonary TB was diagnosed in five persons (1.11%), and 62 (13.8%) had radiographic evidence of inactive pulmonary TB. Tuberculosis infection was associated with age and smoking, but not with sex or alcohol abuse. No significant differences in infection rates were found between the main group and 48 homeless co-residents of smear-positive subjects. Only 16.9% of the homeless with active TB in Barcelona in the same period were diagnosed through active case-finding, the remainder being mainly detected in hospitals (69.8%) and other several centres (13.3%). CONCLUSIONS: Homeless individuals have a very high risk of TB infection and disease and contact investigation requires specific methods for them. Programmes of screening and supervised treatment should be ensured in this group.
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Personas con Mala Vivienda , Tuberculosis Pulmonar/epidemiología , Adolescente , Adulto , Factores de Edad , Anciano , Alcoholismo , Femenino , Humanos , Masculino , Tamizaje Masivo , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Factores Sexuales , Fumar/efectos adversos , España/epidemiología , Prueba de Tuberculina , Tuberculosis Pulmonar/diagnósticoRESUMEN
We have made the first direct symmetry tests in the decays of polarized Z0 bosons into fully identified bbg states, collected in the SLD experiment at SLAC. We searched for evidence of parity violation at the bbg vertex by studying the asymmetries in the b-quark polar- and azimuthal-angle distributions, and for evidence of T-odd, CP-even or CP-odd, final-state interactions by measuring angular correlations between the three-jet plane and the Z0 polarization. We found results consistent with standard model expectations and set 95% C. limits on anomalous contributions.