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The axial coupling of the nucleon, gA, is the strength of its coupling to the weak axial current of the standard model of particle physics, in much the same way as the electric charge is the strength of the coupling to the electromagnetic current. This axial coupling dictates the rate at which neutrons decay to protons, the strength of the attractive long-range force between nucleons and other features of nuclear physics. Precision tests of the standard model in nuclear environments require a quantitative understanding of nuclear physics that is rooted in quantum chromodynamics, a pillar of the standard model. The importance of gA makes it a benchmark quantity to determine theoretically-a difficult task because quantum chromodynamics is non-perturbative, precluding known analytical methods. Lattice quantum chromodynamics provides a rigorous, non-perturbative definition of quantum chromodynamics that can be implemented numerically. It has been estimated that a precision of two per cent would be possible by 2020 if two challenges are overcome1,2: contamination of gA from excited states must be controlled in the calculations and statistical precision must be improved markedly2-10. Here we use an unconventional method 11 inspired by the Feynman-Hellmann theorem that overcomes these challenges. We calculate a gA value of 1.271 ± 0.013, which has a precision of about one per cent.
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The combination of multiple observational probes has long been advocated as a powerful technique to constrain cosmological parameters, in particular dark energy. The Dark Energy Survey has measured 207 spectroscopically confirmed type Ia supernova light curves, the baryon acoustic oscillation feature, weak gravitational lensing, and galaxy clustering. Here we present combined results from these probes, deriving constraints on the equation of state, w, of dark energy and its energy density in the Universe. Independently of other experiments, such as those that measure the cosmic microwave background, the probes from this single photometric survey rule out a Universe with no dark energy, finding w=-0.80_{-0.11}^{+0.09}. The geometry is shown to be consistent with a spatially flat Universe, and we obtain a constraint on the baryon density of Ω_{b}=0.069_{-0.012}^{+0.009} that is independent of early Universe measurements. These results demonstrate the potential power of large multiprobe photometric surveys and pave the way for order of magnitude advances in our constraints on properties of dark energy and cosmology over the next decade.
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Observation of neutrinoless double beta decay, a lepton number violating process that has been proposed to clarify the nature of neutrino masses, has spawned an enormous world-wide experimental effort. Relating nuclear decay rates to high-energy, beyond the standard model (BSM) physics requires detailed knowledge of nonperturbative QCD effects. Using lattice QCD, we compute the necessary matrix elements of short-range operators, which arise due to heavy BSM mediators, that contribute to this decay via the leading order π^{-}âπ^{+} exchange diagrams. Utilizing our result and taking advantage of effective field theory methods will allow for model-independent calculations of the relevant two-nucleon decay, which may then be used as input for nuclear many-body calculations of the relevant experimental decays. Contributions from short-range operators may prove to be equally important to, or even more important than, those from long-range Majorana neutrino exchange.
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Novel endogenous cDNAs of beta-1, 4-endoglucanases (Oa-EGase I and Oa-EGase II) were cloned from the cerambycid beetle Oncideres albomarginata chamela. Oa-EGase I- and Oa-EGase II-deduced proteins and three-dimensional structures possess all features, including general architecture, signature motifs and catalytic domains, of glycosyl hydrolase families 5 and 45 (GHF5 and GHF45) and also share high levels of homology with other beetle cellulases. Total carboxymethylcellulase activity of O. a. chamela was 208.13 U/g of larvae. Phylogenetic analyses suggest that insect GHF5 and GHF45 are very ancient gene families and indicate, at least in the case of GHF5, that this family likely evolved from a common ancestor rather than, as is often reported, via horizontal gene transfer. Beetle GHF45 cellulases did not cluster with other metazoan cellulases. However, the presence of GHF45 cellulases in ancient molluscan taxa puts into question the hypothesis of horizontal gene transfer for the evolution of cellulases in animals.
Assuntos
Celulase/genética , Besouros/enzimologia , Besouros/genética , DNA Complementar/genética , Evolução Molecular , Modelos Moleculares , Homologia Estrutural de Proteína , Sequência de Aminoácidos , Animais , Southern Blotting , Celulase/química , Celulase/metabolismo , Clonagem Molecular , Ensaios Enzimáticos , Dados de Sequência Molecular , Filogenia , Estrutura Secundária de Proteína , Alinhamento de SequênciaRESUMO
BACKGROUND: The Cuban population is essentially a result of the admixture between Spanish, West African and, to a lesser degree, Amerindian tribes that inhabited the island. AIM: The study analysed the genetic structure of the three principal ethnic groups from Havana City, and the contribution of parental populations to its genetic pool. SUBJECTS AND METHODS: According to genealogical information and anthropological traits, 206 subjects were classified as Mulatto, of Spanish decent or of African descent. Seventeen Ancestry Informative Markers, with high difference in frequency between parental populations, were selected to estimate individual and group admixture proportions. The statistical analyses were performed using the ADMIX, ADMIX95 and STRUCTURE 2.1 packages. RESULTS: The results demonstrate a high level of European and African admixture in Mulattos (57-59% European; 41-43% West African). The European contribution was higher in those of Spanish descent (85%) while in those of African descent, the West African contribution ranged between 74% and 76%. Genetic structure was only detected in Mulattos and those of African descent. An Amerindian contribution was not detectable in the studied sample. CONCLUSION: Our findings indicate the existence of admixture and genetic structure in the population of Havana City. This study represents one of the first steps towards understanding Cuban population admixture in order to produce successful experimental designs for admixture mapping.
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População Negra/genética , Etnicidade/genética , Indígenas Sul-Americanos/genética , População Urbana/estatística & dados numéricos , População Branca/genética , Adulto , África Ocidental/etnologia , Antropometria , Doadores de Sangue , Cuba , Etnicidade/estatística & dados numéricos , Feminino , Frequência do Gene , Marcadores Genéticos , Humanos , Masculino , Casamento , Polimorfismo de Nucleotídeo Único , Espanha/etnologiaRESUMO
Klebsiella spp. isolates from community-acquired infections were characterized. A total of 39 Klebsiella spp. isolates were obtained from outpatients at four rural hospitals in Mexico (2013-2014). The biochemical tests identified all as being K. pneumoniae. The molecular multiplex-PCR test identified 36 (92.4%) K. pneumoniae isolates and one (2.5%) K. variicola isolate, and phylogenetic analysis of the rpoB gene identified two isolates (5.1%) belonging to K. quasipneumoniae subsp. quasipneumoniae and K. quasivariicola. The last one was confirmed by phylogenetic analysis of six-loci concatenated genes. Mostly the isolates were multidrug resistant; however, a minority were extended-spectrum ß-lactamase producing (10.2%). The extended-spectrum ß-lactamase CTX-M-15 gene was identified in these isolates. Analysis of biofilm production and the hypermucoviscosity phenotype showed a total of 35 (92.3%) and seven (17.9%) of the isolates were positive for these phenotypes respectively. The K2 (4/39, 10.2%), K5 (2/39, 5.1%) and K54 (1/39, 2.5%) serotypes were identified in seven (17.9%) of the isolates, and only 28.5% (2/7) hypermucoviscous isolates were positive for the K2 and K5 serotypes. In general, the sequence type (ST) analysis and phylogenetic analysis of seven multilocus sequence typing loci were heterogeneous; however, ST29 was the most prevalent ST in the analysed isolates, accounting for 19% (4/21) of the total isolates. Two of the four ST29 isolates had the hypermucoviscosity phenotype. The virulence factors for fimbriae were the most prevalent, followed by siderophores. Community-acquired infections are caused by various species from Klebsiella genus, with different profiles of antibiotic resistance and heterogeneous virulence factors.
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The study of the composition of the intestinal flora is important to the health of the host, playing a key role in maintaining intestinal homeostasis and the evolution of the immune system. For these studies, various universal primers of the 16S rDNA gene are used in microbial taxonomy. Here, we report an evaluation of 5 universal primers to explore the presence of microbial DNA in colon biopsies preserved in RNAlater solution. The DNA extracted was used for the amplification of PCR products containing the variable (V) regions of the microbial 16S rDNA gene. The PCR products were studied by restriction fragment length polymorphism (RFLP) analysis and DNA sequence, whose percent of homology with microbial sequences reported in GenBank was verified using bioinformatics tools. The presence of microbes in the colon of rats was quantified by the quantitative PCR (qPCR) technique. We obtained microbial DNA from rat, useful for PCR analysis with the universal primers for the bacteria 16S rDNA. The sequences of PCR products obtained from a colon biopsy of the animal showed homology with the classes bacilli (Lactobacillus spp) and proteobacteria, normally represented in the colon of rats. The proposed methodology allowed the attainment of DNA of bacteria with the quality and integrity for use in qPCR, sequencing, and PCR-RFLP analysis. The selected universal primers provided knowledge of the abundance of microorganisms and the formation of a preliminary test of bacterial diversity in rat colon biopsies.
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Colo/microbiologia , Microbioma Gastrointestinal , Tipagem Molecular/métodos , RNA Ribossômico 16S/genética , Animais , Bactérias/genética , Primers do DNA/genética , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Genes Bacterianos , Masculino , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Fragmento de Restrição , Ratos , Análise de Sequência de DNARESUMO
pupae of Ceratitis capitata that were about to hatch were sterilized with Gamma(10 krds). Residual Malathionr was applied at 0.001, 0.01, 0.1, 1.0 and 10 micrograms/ml. A level of 0.0904 produced the highest mortality in females that reached sexual maturity and were irradiated as pupae (lowest for mature, non-irradiated males).
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Inibidores da Colinesterase/farmacologia , Dípteros/efeitos dos fármacos , Inseticidas/farmacologia , Malation/farmacologia , Animais , Costa Rica , Dípteros/genética , Dípteros/crescimento & desenvolvimento , Dípteros/efeitos da radiação , Feminino , Proteínas de Insetos/antagonistas & inibidores , Resistência a Inseticidas/genética , Resistência a Inseticidas/efeitos da radiação , Dose Letal Mediana , Masculino , México , PupaRESUMO
The author discusses his department's conversion to a new incident reporting system--why the decision was made, how the program was set up and data were entered, the purchase and installation of new computers, the computer network itself, the flow plan for reports, how training was conducted, and what problems had to be overcome.
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Departamentos Hospitalares/organização & administração , Sistemas de Informação Hospitalar , Gestão de Riscos , Medidas de Segurança/organização & administração , Sistemas Computacionais , Inovação Organizacional , Resolução de Problemas , Desenvolvimento de Programas , Design de Software , TexasRESUMO
The security problems faced by a recently opened psychiatric center located on the campus of a hospital--including staffing, fire safety, access control, patient restraints, and budget cuts--and how they are being dealt with.
Assuntos
Hospitais Psiquiátricos/organização & administração , Modelos Organizacionais , Medidas de Segurança/organização & administração , Orçamentos , Hospitais com 300 a 499 Leitos , Hospitais Psiquiátricos/economia , Hospitais de Ensino/organização & administração , Capacitação em Serviço , Afiliação Institucional , Restrição Física , TexasRESUMO
A collection of 15 carbapenem-resistance Acinetobacter baumannii clinical isolates was analysed on two tertiary hospitals in Mexico. The OXA-51 was identified in all isolates, followed by OXA-239 and OXA-58; OXA-239 is described as a new OXA-23-like allele. These carbapenemases were identified on four clonal groups, distributed between two neighbouring hospitals. Acinetobacter baumannii is poorly studied in Mexico; this situation urges the implementation of strategies to prevent its dissemination.
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RESUMEN En la investigación de la percepción visual comúnmente se usan programas computarizados comerciales para la presentación de los estímulos, configurados por lo general para admitir una respuesta por cada estímulo presentado. Sin embargo, el estudio de la percepción multiestable, requiere la presentación de un estímulo que permanece invariable aunque la percepción de éste puede variar en dos o más configuraciones, lo que demanda que el programa admita respuestas para cada cambio en la percepción de un mismo estímulo. Se presenta PercepFiguras desarrollado con lenguaje de programación C++ que es un sistema de estimulación visual que permite al usuario: a) presentar imágenes y recibir una o varias respuestas a cada una, b) sincronizar las respuestas con un sistema de registro electroencefalográfico mediante el envío de pulsos TTL, c) generar un archivo conductual y d) generar un archivo con el total de respuestas y promedios de las latencias a cada tipo de figura. Se realizó un estudio piloto con una tarea de presentación continua de una figura ambigua alternando con dos variantes de menor ambigüedad, se obtuvo mayor frecuencia de cambios perceptuales y menor estabilidad perceptual para la figura ambigua respecto a las de menor ambigüedad, comprobándose la utilidad del programa.
ABSTRACT In the study of visual perception, the use of computerized commercial programs for the presentation of stimuli, usually configured to admit a response for each stimulus presented, is common. However, the study of multistable perception requires the presentation of a stimulus that remains unchanged, although the perception of it can vary in two or more configurations during its observation, which demands that the program admit responses for each change in perception of the same stimulus. PercepFiguras is a system developed with C++ programming language that allows: a) present images and receive multiple responses to the same stimulus, b) synchronize the responses with an electroencephalographic recording system by sending TTL pulses, c) generate a behavioral file, d) generate a file with the total responses and averages of the latencies for each type of figure. In the pilot study with a task of continuous presentation of an ambiguous figure to alternating with two variants of less ambiguity, we observe greater frequency of perceptual and less perceptual stability to the ambiguous figure with respect to the less ambiguous figures, which proves the usefulness of the program.
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Refractive surgery has been used widely in some countries for the last 20 years for the correction of myopia. Radial keratotomy and keratomileusis, the most common procedures, may concur with retinal detachment. A total of 14 eyes in 12 patients, 7 after keratomileusis and 7 after radial keratotomy, which had either asymptomatic or symptomatic retinal breaks, subclinical and clinical rhegmatogenous retinal detachments, or both, are discussed here. Five eyes were treated with either laser photocoagulation or cryopexy alone, seven eyes with a scleral buckling procedure, one eye with vitrectomy, and one eye was not operated on. At the final follow-up examination, anatomic reattachment had been achieved in 12 of 14 eyes (85.7%). Visual acuity improved in 3 eyes (21.4%), remained stable in 9 eyes (64.3%), and was worse in 2 eyes (14.3%). The scleral buckling procedures used in the repair of retinal detachment induced refractive changes by modifying axial length and corneal curvature, with recurrence of myopia and astigmatism. Myopia increased a mean of -3.00 diopters in 6 of 7 eyes (86%). Myopic astigmatism power changed a mean of -1.00 diopter in 5 eyes (71%), and the astigmatic axes shifted in 3 eyes (43%). This situation could be prevented with an early peripheral search for and treatment of peripheral retinal degenerative pathologic changes, by avoiding encircling bucklings, or by using alternative methods of treatment.
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Transplante de Córnea/efeitos adversos , Ceratotomia Radial/efeitos adversos , Miopia/cirurgia , Descolamento Retiniano/etiologia , Adulto , Astigmatismo/etiologia , Criocirurgia , Feminino , Seguimentos , Humanos , Fotocoagulação a Laser , Masculino , Pessoa de Meia-Idade , Descolamento Retiniano/cirurgia , Recurvamento da Esclera , Acuidade VisualRESUMO
We reviewed the medical records of 44 patients who underwent a pars plana vitrectomy to remove posttraumatic intraocular foreign bodies. The group most affected was that of males with a mean age of 28 years, who sustained a job injury, presenting with a single corneal laceration less than 2 mm in extension. There were 31 (70.45%) metallic foreign bodies. At surgery, 27 (61.36%) of the 44 foreign bodies were removed with forceps and 17 (38.63%) with the rare-earth magnet. From these patients, 84.61% obtained a final visual acuity equal or better than that on admission. We did not find a statistically significant difference between the groups with different timing on their vitrectomy, nor between groups presenting with and without vitreous hemorrhage.
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Corpos Estranhos no Olho/cirurgia , Ferimentos Oculares Penetrantes/cirurgia , Instrumentos Cirúrgicos , Vitrectomia/instrumentação , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Magnetismo , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Acuidade Visual , Hemorragia Vítrea/cirurgiaRESUMO
To evaluate the results of using and removing silicone oil in the management of giant retinal tears, 24 cases of vitrectomy with fluid-silicone oil exchange were reviewed. We did not use cryotherapy in any case. For chorioretinal adherence, we used either endolaser or postoperative external laser and a narrow buckle. The retina was reattached successfully in 22 (91.6%) of the 24 eyes. Of these, visual acuity was 20/200 or better in 18 (75%) eyes. This was significantly better than the preoperative visual acuity (P = .02). After removing the silicone oil in 15 cases, 13 (92.8%) had visual acuities of 20/200 or better, which was considerably better than that of the group in which the silicone oil was not removed (P = .006). We recommend removing the silicone oil and additional peeling of membranes an average of six months postoperatively when the eye is stable.
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Perfurações Retinianas/cirurgia , Óleos de Silicone , Adolescente , Adulto , Idoso , Feminino , Seguimentos , Humanos , Terapia a Laser , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Prognóstico , Descolamento Retiniano/cirurgia , Recurvamento da Esclera , Acuidade Visual , VitrectomiaRESUMO
To learn more about postictal behaviors and their underlying mechanisms, five behaviors and EEG recordings were studied following fully generalized, kindled seizures in rats. The behaviors included bar pressing for food; tail withdrawal, squeak, and multiple squeak responses to painful tail shocks; consumption of freely available food; clinging to a vertical grid; and locomotion. Latencies from the end of a seizure afterdischarge until each behavior recovered were compared and were found to cluster in three distinct pairs. Locomotion and grid clinging recovered most quickly; consumption of freely available food and EEG postictal depression recovered next; and bar pressing for food and the multiple squeak response recovered most slowly. Naloxone pretreatment (10 mg/kg but not 1 mg/kg) shortened recovery to multiple squeak responses, grid clinging, and locomotion, without affecting recovery of bar pressing, food consumption, or EEG postictal depression. These results suggest that complex behaviors recover more slowly following a seizure than simple behaviors. It also appears that opioids are released by a kindled seizure and mediate certain postictal changes in motor- and pain-related behaviors.
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Comportamento Animal/efeitos dos fármacos , Excitação Neurológica , Naloxona/farmacologia , Convulsões/fisiopatologia , Animais , Eletroencefalografia , Masculino , Movimento/efeitos dos fármacos , Ratos , Ratos EndogâmicosRESUMO
OBJECTIVE: The objective of this study was to perform an epidemiological analysis of the frequency of anophthalmia/microphthalmia (A/M) in syndromes identified in newborn infants in Spain. PATIENTS AND METHODS: Data of the Spanish Collaborative Study of Congenital Malformations during the period of 1976-1994, corresponding to more than 1,200,000 births, was analyzed. Among these, 86 newborn infants with A/M presented some of the recognized syndromes. RESULTS: There is a wide etiological heterogeneity among the syndromes with this ocular defect, with chromosomal syndromes being the most frequent (67.9% of total syndromes with A/M), followed by monogenic syndromes (19.1%), environmental (9.5%) and those of unknown etiology (3.6%). CONCLUSIONS: Some guidelines when a baby is born with A/M are derived from this study. First, given the tendency of the defect to present together with other anomalies, it is advisable to perform a detailed study to rule out or to confirm the existence of other defects. Adequate samples should be taken (even in stillborn infants) for cytogenetic study. Examine carefully the prenatal history, looking for chronic diseases, infectious processes or exposure to teratogens. Depending on the baby's survival, follow-up of the psychomotor development should be made. All of these aspects are always important in malformed babies, but especially in infants with A/M given the tendency of the defect to present in syndromes as the etiologic diagnosis determines the counselling regarding the risk of recurrence, detection of carriers in some cases and possible prenatal diagnosis.
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Anoftalmia/epidemiologia , Anoftalmia/genética , Humanos , Recém-Nascido , Espanha/epidemiologia , SíndromeRESUMO
La Artritis Reumatoide es una enfermedad de etiología multifactorial, que involucra la presencia de factores genéticos, ambientales, inmunológicos y hormonales. En los últimos años se ha establecido una asociación entre la predisposición a padecer esta enfermedad y la existencia de determinados haplotipos del HLA clase II. El objetivo fundamental de este trabajo es la caracterización del polimorfismo de las moléculas HLA-DQB1 y HLA-DRB de un grupo de pacientes cubanos con Artritis Reumatoide, además analizar una posible correlación entre los niveles de varias citocinas proinflamatorias en un grupo de estos pacientes, con los alelos HLA tipo II genotipados, el sexo y el tiempo de diagnosticada la enfermedad. El estudio se llevo a cabo en 50 pacientes cubanos con el diagnóstico de Artritis Reumatoide y un grupo control, compuesto de 211 donantes sanos. Los haplotipos HLA-DQ y HLA-DRB1 fueron determinados a través de la reacción en cadena de la polimerasa. La cuantificación de las citocinas se realizó empleando inmuno-ensayos comerciales. Los resultados obtenidos en este análisis indican que los alelos con un radio de la razón de probabilidades superior a 2 fueron para el caso de la molécula HLA-DQB 1: HLA-DQB1*03 y *06, y para la molécula HLA-DRB 1 los alelos: *01, *04, *09 y *10. Encontramos además que los niveles de la citocina interferon ganma están significativamente aumentados en los pacientes con menos tiempo de diagnosticada la enfermedad. Este trabajo constituye el primer reporte de caracterización de las moléculas HLA tipo II, a través de técnicas moleculares, en pacientes cubanos con Artritis Reumatoide(AU)
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Artrite Reumatoide/diagnóstico , Antígenos HLA , Linfotoxina-alfaAssuntos
Face/anatomia & histologia , Recém-Nascido , Antropometria , Feminino , Humanos , Masculino , MéxicoRESUMO
1q Helicobacter pylori (HP) es una bacteria Gram (-) que coloniza el antro gastrico en mas del 90// de los pacientes con ulcera duodenal o gastrica y en 50 a 70// de pacientes con dispepsia no ulcerosa. Esta presente tambien, en individuos asintomaticos y en pacientes con enfermedad hepatica alcoholica. En el presente trabajo se realizo un estudio retrospectivo de todos los pacientes sometidos a biopsia endoscopica y que presentaron sintomatologia del tracto digestivo superior en el IGBJ durante un periodo de 2 anos y medio. Se revisaron 516 fichas, de las cuales 279 tenian diagnostico histopatologico positivo para HP, de las que 53// eran del sexo masculino y 47// femenino. Los grupos de edad mas afectados estaban comprendidos entre 21-30 anos y 31 y 40. El diagnostico endoscopico mas frecuente fue gastritis cronica 49//; la histopatologia demostro gastritis cronica en un 48//. Clinicamente, los sintomas mas sobresalientes fueron: dolor abdominal epigastrico (70//), de tipo urente (63//) y pirosis retroesternal (38//). La imagen endoscopica atribuible a HP fue polimorfa, con cambios atrofica de la mucosa antral, presentando desde un aspecto de empedrado, hasta engrosamiento congestivo de pliegues con erosion central cubierta por fibrina, pasando por areas zonales (spots) congestiva alterando con mucosa de cloracion normal.