993 resultados para Anomalies immunitaires


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Benign and malignant thyroid tumors constitute a wide range of neoplasias showing recurrent chromosome abnormalities. In an attempt to characterize specific numerical chromosome abnormalities in thyroid tissues, We present here the findings from a study of archival samples depicted by 10 malignant tumors, 30 benign lesions, and 10 normal thyroid tissues. Fluorescence in situ hybridization was performed on noncultured samples using biotinylated centromere-specific probes for chromosomes 7, 10, and 17. Trisomy or tetrasomy 7 were present in 19 benign and in 7 malignant tumors. Trisomy 10 or 17 were observed in 18 adenomas or goiters and in 9 carcinomas, and monosomy 17 was seen in 2 carcinomas. Our findings suggest that such abnormalities are an in vivo phenomenon and may be important in the neoplastic proliferation of thyroid gland. (C) Elsevier B.V., 2000. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

It is argued, contrary to various claims and expectations, that the phase shifts calculated via variational principles for the t matrix involving complex algebra may exhibit anomalous behavior. These anomalies are numerically demonstrated in the case of the complex Kohn and the Newton variational principles for the t matrix and are expected to appear for other similar variational principles for the t matrix, such as the Takatsuka-McKoy variational principle.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We report on two unrelated Brazilian girls born to normal and nonconsanguineous parents and presenting ectodermal dysplasia, ectrodactyly, clefting, tear duct anomalies, and micro/anophthalmia. The clinical picture presented by these patients suggests the diagnosis of Goltz-Gorlin (Focal dermal hypoplasia) syndrome and EEC syndrome.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Polycrystalline or single-crystal ferroelectric materials present dielectric dispersion in the frequency range 100 MHz-1 GHz that has been attributed to a dispersive ( relaxation-like) mechanism as well as a resonant mechanism. Particularly in 'normal' ferroelectric materials, a dielectric response that is indistinguishable from dispersion or a resonance has been reported. Nevertheless, the reported results are not conclusive enough to distinguish each mechanism clearly. A detailed study of the dielectric dispersion phenomenon has been carried out in PbTiO3-based ferroelectric ceramics, with the composition Pb1-xLaxTiO3 (x = 0.15), over a wide range of temperatures and frequencies, including microwave frequencies. The dielectric response of La-modified lead titanate ferroelectric ceramics, in 'virgin' and poled states, has been investigated in the temperature and frequency ranges 300-450 K and 1 kHz-2 GHz, respectively. The results revealed that the frequency dependence of the dielectric anomalies, depending on the measuring direction with respect to the orientation of the macroscopic polarization, may be described as a general mechanism related to an 'over-damped' resonant process. Applying either a uniaxial stress along the measurement field direction or a poling electric field parallel and/or perpendicular to the measuring direction, a resonant response of the real and imaginary components of the dielectric constant is observed, in contrast to the dispersion behavior obtained in the absence of the stress, for the 'virgin' samples. Both results, resonance and/or dispersion, can be explained by considering a common mechanism involving a resonant response (damped and/or over-damped) which is strongly affected by a ferroelastic-ferroelectric coupling, contributing to the low-field dielectric constant.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

It is demonstrated, contrary to various claims, that the phase shifts calculated via variational principles involving the Green function may exhibit anomalous behavior. These anomalies may appear in variational principles for the K matrix (Schwinger variational principle) of potential V, for (K-V) (Kohn-type and Newton variational principles), and other variational principles of higher order (Takatsuka-McKoy variational principle).

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We discuss the problem of the breakdown of conformal and gauge symmetries at finite temperature in curved-spacetime background, when the changes in the background are gradual, in order to have a well-defined quantum field theory at finite temperature. We obtain the expressions for Seeley's coefficients and the heat-kernel expansion in this regime. As applications, we consider the self-interacting lambdaphi4 and chiral Schwinger models in curved backgrounds at finite temperature.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The aim of this study was to evaluate the effects of exercise prior to or during pregnancy on maternal reproductive outcome, biochemical profile, and on fetal anomaly frequency in a rat pregnancy model utilizing chemically induced diabetes. Wistar rats (minimum n = 11 animals/group) were randomly assigned the following groups: group 1 (G1), sedentary, nondiabetic; G2, nondiabetic, exercised during pregnancy; G3, nondiabetic, exercised prior to and during pregnancy; G4, sedentary, diabetic; G5, diabetic, exercised during pregnancy; and G6, diabetic, exercised prior to and during pregnancy. A swimming program was utilized for moderate exercise. On day 21 of pregnancy, all rats were anesthetized to obtain blood for biochemical measurements. The gravid uterus was weighed with its contents, and the fetuses were analyzed. The nondiabetic rats exercised prior to pregnancy presented a reduced maternal weight gain. Besides, G2 and G3 groups showed decreased fetal weights at term pregnancy, indicating slight intrauterine growth restriction (IUGR). In the diabetic dams, the swimming program did not have antihyperglycemic effects. The exercise applied only during pregnancy caused severe IUGR, as confirmed by reduced fetal weight mean, fetal weight classification, and ossification sites. Nevertheless, exercise was not a teratogenic factor and improved the rats' lipid profiles, demonstrating that the exercise presented possible benefits, but there are also risks prior and during pregnancy, especially in diabetic pregnant women. © The Author(s) 2012.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In vitro production and somatic cell nuclear transfer are biotechnologies widely used for breeding cattle, although may result in congenital anomalies. This paper aims to report a set of congenital anomalies in two Nelore calves, a male and a female, produced through in vitro fertilization. The major anomalies revealed at necropsy were hypospadias, bifid scrotum, atresia ani and rectum ending in blind pouch in the male calf. In the female calf accessory spleen, atresia ani, underdevelopment of extern genitalia and urethral orifice, and rectum ending in blind pouch forming a uterus-rectum fistula were observed.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The purposes of this study were to investigate radiographically the dental and maxillomandibular in patients with neuropsychomotor disorders and determine the role of panoramic radiographs for quantitative and qualitative analyses of dental alterations. A total of 322 panoramic radiographs from 190 males and 132 females aged 4 to 57 years were obtained from the files of the Center for Care to Patients with Special Needs (CAPE; Dental School, University of São Paulo) and subdivided into syndromes, special needs, neurological, neuromuscular or cerebral disorders, and sequels of diseases. 32% of dental alterations were in tooth position, with 69% of this group associated with tooth rotation. The mandible accounted for 54.62% of alterations. The male gender (55.85%) and the permanent dentition (78.7%) were most affected. Panoramic radiographs were proved to be well suited for quantitative evaluation of dental anomalies of epidemiological nature. Panoramic radiographs are important diagnostic resources when applied to patients with special needs because of the difficulty to place intraoral films and held them correctly positioned during the radiographic technique.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

OBJECTIVE: To determine the prevalence of mesiodens in deciduous and mixed dentitions and its association with other dental anomalies. MATERIAL AND METHODS: Panoramic radiographs of 1,995 orthodontic patients were analyzed retrospectively, obtaining a final sample of 30 patients with mesiodens. The following aspects were analyzed: gender ; number of mesiodens; proportion between erupted and non-erupted mesiodens; initial position of the supernumerary tooth; related complications; treatment plan accomplished; and associated dental anomalies. The frequency of dental anomalies in the sample was compared to reference values for the general population using the chi-square test (c²), with a significance level set at 5%. RESULTS: The prevalence of mesiodens was 1.5% more common among males (1.5:1). Most of the mesiodens were non-erupted (75%) and in a vertical position, facing the oral cavity. Extraction of the mesiodens was the most common treatment. The main complications associated with mesiodens were: delayed eruption of permanent incisors (34.28%) and midline diastema (28.57%). From all the dental anomalies analyzed, only the prevalence of maxillary lateral incisor agenesis was higher in comparison to the general population. CONCLUSION: There was a low prevalence of mesiodens (1.5%) in deciduous and mixed dentition and the condition was not associated with other dental anomalies, except for the maxillary lateral incisor agenesis.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Cancer is the third most frequent cause of death in children in Brazil. Early diagnosis and medical advances have significantly improved treatment outcomes, which has resulted in higher survival rates and the management of late side effects has become increasingly important in caring for these patients. Dental abnormalities are commonly observed as late effects of antineoplastic therapy in the oral cavity. The incidence and severity of the dental abnormalities depend on the child's age at diagnosis and the type of chemotherapeutic agent used, as well as the irradiation dose and area. The treatment duration and aggressivity should also be considered. Disturbances in dental development are characterized by changes in shape, number and root development. Enamel anomalies, such as discoloration, opacities and hypoplasia are also observed in these patients. When severe, these abnormalities can cause functional and esthetic sequelae that have an impact on the children's and adolescents' quality of life. General dentists and pediatric dentists should understand these dental abnormalities and how to identify them aiming for early diagnosis and appropriate treatment.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)