1000 resultados para Modelo ocular


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We examined the correlation between results obtained from the in vivo Draize test for ocular irritation and in vitro results obtained from the sheep red blood cell (RBC) haemolytic assay, which assesses haemolysis and protein denaturation in erythrocytes, induced by cosmetic products. We sought to validate the haemolytic assay as a preliminary test for identifying highly-irritative products, and also to evaluate the in vitro test as alternative assay for replacement of the in vivo test. In vitro and in vivo analyses were carried out on 19 cosmetic products, in order to correlate the lesions in the ocular structures with three in vitro parameters: (i) the extent of haemolysis (H50); (ii) the protein denaturation index (131); and (iii) the H50/DI ratio, which reflects the irritation potential (IP). There was significant correlation between maximum average scores (MAS) and the parameters determined in vitro (r = 0.752-0.764). These results indicate that the RBC assay is a useful and rapid test for use as a screening method to assess the IP of cosmetic products, and for predicting the IP value with a high level of concordance (94.7%). The assay showed high sensitivity and specificity rates of 91.6% and 100%, respectively.

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Purpose To determine the relationship between ocular hypertension and glaucoma in patients with Graves` orbitopathy. Methods A total of 107 patients with a diagnosis of Graves` orbitopathy, followed at the Oculoplasty sector of the University Hospital, Medical School of Ribeirao Preto, were evaluated by applanation tonometry, computed visual campimetry (Humphrey 30-2, Full Threshold) and analysis and photographic documentation of the optic nerve. The patients considered to have the suspicion of glaucoma were re-evaluated 1 year later for diagnostic confirmation or exclusion. Results A 3.74% prevalence of ocular hypertension (four patients) and a 2.8% prevalence of glaucoma (three patients) was observed. When considering only patients older than 40 years, the prevalence of ocular hypertension was 5.4% (four patients) and the prevalence of glaucoma was 4.76% (three patients). Conclusion The present study did not reveal a statistically significant difference in the prevalence of ocular hypertension or glaucoma between patients with Graves` orbitopathy and the general population.

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A 14-year-old spayed female domestic short-haired cat was presented for evaluation of a mass in the right eye. Ophthalmic examination revealed a blind right eye and presence of two distinct masses: a pink and a red-to-brown mass, the latter occupying most of the cornea and part of the conjunctiva. Exenteration was performed under general anesthesia, and the ocular tissues were processed routinely for histopathology. Upon microscopic examination, a malignant epithelial neoplasm and a benign vascular neoplasm were present in the cornea. The conjunctiva and the third eyelid were also affected. Upon immunohistochemistry, the epithelial tumor was positive for cytokeratin and negative for vimentin and the endothelial tumor was negative for cytokeratin and positive for vimentin. A diagnosis of squamous cell carcinoma (SCC) and hemangioma was made. The SCC was affecting the cornea, bulbar conjunctiva (lateral and inferior) and the base of the third eyelid, whereas the hemangioma was affecting the cornea and medial limbus. To the authors` knowledge, this is the first report of concomitant SCC and hemangioma affecting the ocular surface in a cat.

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Many coral reef fish are beautifully coloured and the reflectance spectra of their colour patterns may include UVa wavelengths (315-400 nm) that are largely invisible to the human eye (Losey, G. S., Cronin, T. W., Goldsmith, T. H., David, H., Marshall, N. J., & McFarland, W.N, (1999). The uv visual world of fishes: a review. Journal of Fish Biology, 54, 921-943; Marshall, N. J. & Oberwinkler, J. (1999). The colourful world of the mantis shrimp. Nature, 401, 873-874). Before the possible functional significance of UV patterns can be investigated, it is of course essential to establish whether coral reef fishes can see ultraviolet light. As a means of tackling this question, in this study the transmittance of the ocular media of 211 coral reef fish species was measured. It was found that the ocular media of 50.2% of the examined species strongly absorb light of wavelengths below 400 nm, which makes the perception of UV in these fish very unlikely. The remaining 49.8% of the species studied possess ocular media that do transmit UV light, making the perception of UV possible. (C) 2001 Elsevier Science Ltd. All rights reserved.

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Germline variants in the melanocortin 1 receptor gene (MC1R) and the p16 gene (CDKN2A) are associated with an increased risk of cutaneous melanoma. The frequency of these germline variants was examined in a population-based, incident series of 62 ocular melanoma cases and ethnicity-matched population controls. In both cases and controls, 59% of individuals carried at least one MC1R variant and there were no significant differences in the frequency of any of the five most common variants of MC1R. We also found no significant differences between cases and controls in the frequency of any of the four most common variants of CDKN2A, and no melanoma case carried a deleterious germline CDKN2A mutation. Our findings argue against an important predisposing effect of the MC1R and CDKN2A genes for ocular melanoma.

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To define the location of potential oncogenes and tumor suppressor genes in ocular melanoma we carried out comparative genomic hybridization (CGH) analysis on a population-based series of 25 formalin-fixed, paraffin-embedded primary tumors comprising 17 choroidal, 2 ciliary body, 4 iris, and 2 conjunctival melanomas. Twelve (48%) of the 25 melanomas showed no chromosomal changes and 13 (52%) had at least one chromosomal gain or loss. The mean number of CGH changes in all tumors was 3.3, with similar mean numbers of chromosomal gains (1.5) and losses (1.8). The highest number of chromosomal changes (i.e., nine) occurred in a conjunctival melanoma and included four changes not observed in tumors at any other ocular site (gains in 22q and 11p and losses in 6p and 17p). The most frequent gains in all primary ocular melanomas were on chromosome arm 8q (69%), 6p (31%) and 8p (23%) and the most frequent losses were on 6q (38%), 10q (23%), and 16q (23%). The most common pairing was gain in 8p and gain in 8q, implying a whole chromosome copy number increase; gains in 8p occurred only in conjunction with gains in 8q. The smallest regions of copy number alteration were mapped to gain of 8q21 and loss of 6q21, 10q21, and 16q22. Sublocalization of these chromosomal changes to single-band resolution should accelerate the identification of genes involved in the genesis of ocular melanoma.

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The visual biology of Hawaiian reef fishes was explored by examining their eyes for spectral sensitivity of their visual pigments and for transmission of light through the ocular media to the retina. The spectral absorption curves for the visual pigments of 38 species of Hawaiian fish were recorded using microspectrophotometry. The peak absorption wavelength (lambda(max)) of the rods varied from 477-502 nm and the lambda(max) of individual species conformed closely to values for the same species previously reported using a whole retina extraction procedure. The visual pigments of single cone photoreceptors were categorized, dependent on their lambda(max)-values, as ultraviolet (347-376 nm), violet (398-431 nm) or blue (439-498 nm) sensitive cones. Eight species possessed ultraviolet-sensitive cones and 14 species violet-sensitive cones. Thus, 47% of the species examined displayed photosensitivity to the short-wavelength region of the spectrum. Both identical and nonidentical paired and double cones were found with blue sensitivity or green absorption peaks (> 500 nm). Spectrophotometry of the lens, cornea, and humors for 195 species from 49 families found that the spectral composition of the light transmitted to the retina was most often limited by the lens (73% of species examined). Except for two unusual species with humor-limited eyes, Acanthocybium solandri (Scombridae) and the priacanthid fish, Heteropriacanthus cruentatus, the remainder had corneal-limited eyes. The wavelength at which 50% of the light was blocked (T50) was classified according to a system modified from Douglas and McGuigan (1989) as Type I, T50 < = 355 nm, (32 species); Type IIa, 355 < T50 < = 380 nm (30 species); Type IIb, 380 < T50 405 nm (84 species). Possession of UV-transmitting ocular media follows both taxonomic and functional lines and, if the ecology of the species is considered, is correlated with the short-wavelength visual pigments found in the species. Three types of short-wavelength vision in fishes are hypothesized: UV-sensitive, UV-specialized, and violet-specialized. UV-sensitive eyes lack UV blockers (Type I and IIa) and can sense UV light with the secondary absorption peak or beta peak of their longer wavelength visual pigments but do not possess specialized UV receptor cells and, therefore, probably lack UV hue discrimination. UV-specialized eyes allow transmission of UV light to the retina (Type I and IIa) and also possess UV-sensitive cone receptors with peak absorption between 300 and 400 nm. Given the appropriate perceptual mechanisms, these species could possess true UV-color vision and hue discrimination. Violet-specialized eyes extend into Type IIb eyes and possess violet-sensitive cone cells. UV-sensitive eyes are found throughout the fishes from at least two species of sharks to modern bony fishes. Eyes with specialized short-wavelength sensitivity are common in tropical reef fishes and must be taken into consideration when performing research involving the visual perception systems of these fishes. Because most glass and plastics are UV-opaque, great care must be taken to ensure that aquarium dividers, specimen holding containers, etc., are UV-transparent or at least to report the types of materials in use.

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When asked to compare two lateralized shapes for horizontal size, neglect patients often indicate the left stimulus to be smaller. Gainotti and Tiacci (1971) hypothesized that this phenomenon might be related to a rightward bias in the patients' gaze. This study aimed to assess the relation between this size underestimation and oculomotor asymmetries. Eye movements were recorded while three neglect patients judged the horizontal extent of two rectangles. Two experimental manipulations were performed to increase the likelihood of symmetrical scanning of the stimulus display. The first manipulation entailed a sequential, rather than simultaneous presentation of the two rectangles. The second required adaptation to rightward displacing prisms, which is known to reduce many manifestations of neglect. All patients consistently underestimated the left rectangle, but the pattern of verbal responses and eye movements suggested different underlying causes. These include a distortion of space perception without ocular asymmetry, a failure to view the full leftward extent of the left stimulus, and a high-level response bias. Sequential presentation of the rectangles and prism adaptation reduced ocular asymmetries without affecting size underestimation. Overall, the results suggest that leftward size underestimation in neglect can arise for a number of different reasons. Incomplete leftward scanning may perhaps be sufficient to induce perceptual size distortion, but it is not a necessary prerequisite.

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A arquitetura de inform??tica do IBGE busca refletir a evolu????o das Tecnologias da Informa????o e de Comunica????o (TIC) e vem sendo modificada ao longo dos anos, de maneira a manter - se um equil??brio entre os anseios e diretrizes institucionais e governamentais. A partir do aprendizado e do sucesso obtidos no Censo Demogr??fico 2010, o IBGE inova agora na forma de administrar sua ??rea de TIC, baseado em software especialista adquirido.O IBGE se beneficia da administra????o dos bens de inform??tica, da responsabilidade sobre contratos, da gest??o do patrim??nio, do uso otimizado dos softwares comerciais, da agilidade de obten????o de informa????es sobre o parque computacional instalado, do monitoramento on-line dos servi??os oferecidos pela TI, da economia de gastos com viagens para suporte t??cnico dentro dos estados e entre os mesmos, da reeduca????o de funcion??rios quanto ao uso de tecnologias, da forma organizada e planejada de trabalho e, portanto, da gest??o p??blica das TIC

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A fun????o capacita????o passa a ser concebida dentro de uma nova proposta materializada no modelo Pool de Capacita????o que tem por objetivos aumentar a capacidade do processo, alinhar a ??rea de recursos humanos ??s estrat??gias institucionais e sintoniz??-la com a cultura organizacional e os cen??rios externos. O processo de capacita????o passa a operar de forma sist??mica, desconcentrada e articulada em rede interna e externa

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O Minist??rio do Trabalho e Emprego, por interm??dio de sua Secretaria de Inspe????o do Trabalho, vem desenvolvendo arrojado programa de metas, visando diminuir os altos ??ndices de informalidade na contrata????o de m??o-de-obra. Al??m de ilegal, tal situa????o provoca graves preju??zos aos trabalhadores. Visando superar este contexto no meio rural, a Secretaria de Inspe????o do Trabalho lan??ou o projeto denominado "Condom??nio de Empregadores". O Condom??nio de Empregadores ?? a uni??o de produtores rurais pessoas f??sicas, com a ??nica finalidade de contratar diretamente empregados rurais, sendo outorgados a um dos produtores poderes para contratar e gerir a m??o-de-obra em suas propriedades. Iniciado em julho de 1999, o projeto consiste na capacita????o dos auditores fiscais, no estabelecimento de parcerias com institui????es governamentais e n??o governamentais e na implanta????o desse novo modelo de contrata????o em ??mbito nacional. Com o apoio do Minist??rio P??blico do Trabalho, do Instituto Nacional de Seguridade Social e de entidades representativas dos trabalhadores e segmento patronal, j?? foram implantados condom??nios no Paran??, Minas Gerais e S??o Paulo. Espera-se at?? o final do ano a cria????o de condom??nios em quase todo o territ??rio nacional, com a regulariza????o de dezenas de milhares de v??nculos laborais

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Texto que focaliza o processo de surgimento e desenvolvimento do modelo gerencial (managerialism ou public management) no campo da administra????o p??blica, analisando seus limites e potencialidades, mediante a abordagem do caso ingl??s e americano de reformas administrativas de governo, ao longo das d??cadas de 80 e 90; ao final, al??m do perfil das principais mudan??as administrativas que t??m afetado o setor p??blico em escala mundial, um coment??rio breve sobre o caso brasileiro.

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Este Caderno traz dois relat??rios de pesquisa internacionais. O primeiro objetiva fazer um levantamento do que se sabe sobre organiza????es de aprendizagem, traduzir as informa????es resultantes em orienta????es pr??ticas e desenvolver abordagens que possam ajudar gerentes a transformar seus locais de trabalho. O segundo relat??rio objetiva verificar a exist??ncia de um modelo canadense de administra????o p??blica canadense, identificando suas principais caracter??sticas distintivas de outros modelos