4,036 research outputs found
Intraosseous mandibular hemangioma : a case report and review of the literature
Intraosseous vascular lesions are rare conditions, comprising only 0.5% to 1% of all intraosseous tumors. They mainly occur in the second decade of life especially in women. The most common locations are the vertebral column and skull; nevertheless, the mandible is a quite rare location. According to the World Health Organization, hemangiomas are benign vasoformative neoplasms of endothelial origin. However, the origin of central hemangioma is debatable. Some authors believe that it is a true neoplasm, whereas others state it is a hamartomatous lesion. Clinically, the patient may be completely symptom-free or may present discomfort, pulsatile bleeding, bluish discoloration, mobile teeth, derangement of the arch form or accelerated dental exfoliation. Most frequently radiographic finding is a multilocular radiolucent image with honeycombs or soap bubble appearance. Differential diagnosis includes neoplasms such as ameloblastoma, cystic lesions such as residual cyst, keratocyst and fibro-osseous lesions such as fibrous dysplasia. There are some therapeutic alternatives, although wide surgical excision remains as the gold standard. We now present a case report of a 51-year-old woman diagnosed in a mandibular hemangioma. Clinical, radiological and histological features of this unusual tumor are described
Solitary fibrous tumor surrounding the carotid sheath
Solitary fibrous tumors (SFTs) are rare spindle cell neoplasms that are mostly found arising from the pleura. Although SFTs recently have been reported in other regions, they are rare in the head and neck and have often been misdiagnosed due to their rarity. SFTs are benign in most cases. Clinically, SFTs usually manifest as wellcircumscribed, slow-growing, smooth and painless masses. Symptoms are often minimal, although they may include sore throat, difficulty in swallowing, change of voice or trismus. CT-Scan and MRI are the most sensitive imaging procedures used. The treatment of choice is complete surgical excision of the lesion. Because recurrences have been noted up to 30 years after surgery, long-term follow up is mandatory. In this article, we present a case of a Solitary Fibrous Tumor arising in the parapharyngeal space in a 20-year-old man, involving the carotid sheath, treated by surgical excision with no recurrence after 1 year. The clinical presentation, surgical management and pathological findings are described
Radiopurity of Micromegas readout planes
Micromesh Gas Amplification Structures (Micromegas) are being used in an
increasing number of Particle Physics applications since their conception
fourteen years ago. More recently, they are being used or considered as readout
of Time Projection Chambers (TPCs) in the field of Rare Event searches (dealing
with dark matter, axions or double beta decay). In these experiments, the
radiopurity of the detector components and surrounding materials is measured
and finely controlled in order to keep the experimental background as low as
possible. In the present paper, the first measurement of the radiopurity of
Micromegas planes obtained by high purity germanium spectrometry in the low
background facilities of the Canfranc Underground Laboratory (LSC) is
presented. The obtained results prove that Micromegas readouts of the microbulk
type are currently manufactured with radiopurity levels below 30 microBq/cm2
for Th and U chains and ~60 microBq/cm2 for 40K, already comparable to the
cleanest detector components of the most stringent low background experiments
at present. Taking into account that the studied readouts were manufactured
without any specific control of the radiopurity, it should be possible to
improve these levels after dedicated development.Comment: 15 pages, 2 figure
Rank two quadratic pairs and surface group representations
Let be a compact Riemann surface. A quadratic pair on consists of a
holomorphic vector bundle with a quadratic form which takes values in fixed
line bundle. We show that the moduli spaces of quadratic pairs of rank 2 are
connected under some constraints on their topological invariants. As an
application of our results we determine the connected components of the
-character variety of .Comment: 37 pages, 1 figur
Neurofibroma plexiforme en mucosa yugal: presentación de un caso clínico
Presentamos un caso clínico de neurofibroma plexiforme localizado
en región geniana, a nivel submucoso. Su interés radica
en que, a pesar de ser el tumor de origen neurógeno más frecuente,
es una entidad poco habitual y que rara vez se localiza
a nivel intraoral. Por otra parte, la variedad plexiforme es todavía
menos frecuente. Desde el punto de vista clínico, se manifiestan
como lesiones anodinas, con escasa sintomatología, que
cuando aparece es derivada de la compresión nerviosa. En nuestro
caso el tumor era asintomático salvo por el tamaño.
Radiológicamente no existe una imagen definitiva. Tiene relación
con determinados síndromes poliglandulares y facomatosis.
El tratamiento es básicamente quirúrgico aunque existen dudas
de la idoneidad del mismo y se están buscando nuevas vías de
tratamiento. Aprovechando la descripción del caso se realiza
una revisión bibliográfica incidiendo en la epidemiología, comportamiento
clínico, métodos diagnósticos, así como en el tratamiento
de este tipo de tumores benignos.The case reported deals with a solitary plexiform neurofibroma
affecting the cheek submucosa.
Neurofibroma is an uncommon tumor which rarely appears in
oral cavity but it represents the most common neurogenic tumor.
Furthermore, plexiform variety is less frequent. Clinically,
oral neurofibromas usually apperars as anodyne and asintomatic
lesions. Sometimes, they produce nervous compression. In this
case, tumor is big but asintomatic. There is no definitive
radiologic image. It has association with poliglandular syndroms
and phacomatosis. The treatment of choice is excision. There
are doubts of the surgical results so that some authors are looking
for new non-surgical treatments. The clinical characteristics,
epidemiology, diagnosis and treatment are described as soon as
a bibliographic revision
Bootstrapping a Portuguese WordNet from Galician, Spanish and English wordnets
Series: Lecture notes in computer science, ISSN 0302-9743, vol. 8854In this article we exploit the possibility on bootstrapping
an European Portuguese WordNet from the English, Spanish and Galician
wordnets using
Probabilistic Translation Dictionaries automatically created from parallel corpora.
The process generated a total of 56~770 synsets and 97~058 variants.
An evaluation of the results using the Brazilian OpenWordNet-PT as a gold standard
resulted on a precision varying from 53\% to 75\% percent, depending on the
cut-line. The results were satisfying and comparable to similar experiments
using the WN-Toolkit.PEst-OE/EEI/UI0752/2014, TIN2012-38584-C06-01, TIN2012-38584-C06-0
Oral leiomyoma in retromolar trigone : a case report
Leiomyomas are bening tumours originated on smooth muscle. The most frequent site of appearance are uterine myometrium, gastrointestinal tract and skin. The highest incidence ocurs between 40 and 49 years of age. Its presentation is unusual in children or in older patients. Leiomyomas are unfrequent in the oral cavity, but in this location are usually localized on tongue, lips and palate. Leiomyomas use to appear as well-defined masses, with slow growth and totally asymptomatic. Pain is present just in rare cases. The treatment is surgical escision. Recurrences are extremely unfrequent. The diagnosis is mainly determined by histological studies due to its unspecific clinical appearance. Histopathologicaly proliferation of smooth muscle cells is observad without necrotic areas. A low number of mitotic figures can be seen. We present the case report of a 25-year old male patient, with a leiomioma on his right retromolar trigone.The low incidence of this pathology, the age of the patient and the inusual location, make the report of the case worthy
Transcultural adaptation and validation of the Spanish language version of the questionnaire OQLQ for the assessment of quality of life in orthognathic patients
Orthognathic surgery is the cornerstone of the treatment of dentofacial deformities, which have a great psychological and social impact on the life of the patient. Patient satisfaction and the impact on quality of life have recently become clinical parameters of growing importance. The aim of this study was to undertake a transcultural adaptation, translation to Spanish and validation of this version of the questionnaire OQLQ, used to measure quality of life in the context of Spanish culture. Validation of the OQLQ questionnaire to the Spanish language was carried out through the methodology of translation and back translation, conceptual equivalence and piloting. The Spanish version was applied through a cross-sectional study to a total of 50 patients undergoing orthognathic surgery. The adapted and validated version showed adequate metric properties of reliability, change sensitivity and validity. In this study, a positive impact of orthognathic surgery on the specific quality of life was evident in 96% of patients, with an average improvement of 58% with respect to the initial score. Dentofacial deformities have a marked negative impact on the lives of patients, with orthognathic surgery being a therapeutic tool of great value in improving the quality of life in social, functional and aesthetic terms. The pilot test of this Spanish language version of the OQLQ proved valid for the assessment of quality of life in Spanish-speaking orthognathic patients or those with a Spanish culture
Advances and perspectives of the use of the entomopathogenic fungi Beauveria bassiana and Metarhizium anisopliae for the control of arthropod pests in poultry production.
Global poultry production is plagued by a wide variety of arthropods. The problems associated with their chemical control have led to an increasing search for control alternatives, and entomopathogenic fungi seem to be a promising strategy. Despite the large number of insects and mites considered as important pests in animal production, studies on the use of entomopathogenic fungi for their control are still scarce compared with agricultural pests, particularly in Brazil. This article reviews some damages and control aspects of the main arthropod pests that affect Brazilian poultry production, including house flies, lesser mealworms, and feather mites, by the use of the entomopathogenic fungi Beauveria bassiana and Metarhizium anisopliae. Studies published in the last 20 years were reviewed, and the main problems and limitations of that pest-control strategy are discussed
Indirect study of 19Ne states near the 18F+p threshold
The early E < 511 keV gamma-ray emission from novae depends critically on the
18F(p,a)15O reaction. Unfortunately the reaction rate of the 18F(p,a)15O
reaction is still largely uncertain due to the unknown strengths of low-lying
proton resonances near the 18F+p threshold which play an important role in the
nova temperature regime. We report here our last results concerning the study
of the d(18F,p)19F(alpha)15N transfer reaction. We show in particular that
these two low-lying resonances cannot be neglected. These results are then used
to perform a careful study of the remaining uncertainties associated to the
18F(p,a)15O and 18F(p,g)19Ne reaction rates.Comment: 18 pages, 8 figures. Accepted in Nuclear Physics
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