950 resultados para Head capsule width
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Head dipping (HD) is a behavioral pattern considered to have a risk assessment or an exploratory role and is used as a complementary parameter to evaluate anxiety in experimental animals. Since rats with electrolytic lesion in the area of the median raphe nucleus displayed high frequencies of HD in a previous study, the present investigation was undertaken to confirm this observation and to determine its anxiety-related origin. HD episodes were counted in adult male Wistar rats (270-350 g) with electrolytic lesion (N = 11) and sham-lesioned controls (N = 12). When HD was measured for 60 min on an elevated open platform, lesioned rats emitted 13 times more HD than controls (264.7 ± 93.3 vs 20.3 ± 7.6 episodes), with the difference being statistically significant (P < 0.05). HD counts during 10-min sessions held 7, 14, 21, 27, and 63 days after lesion showed significantly higher means (range: 28.14 ± 5.38 to 62.85 ± 9.48) compared to sham-lesioned controls (range: 7.37 ± 1.13 to 8.5 ± 1.45). Normal rats stepped down into their home cages when the vertical distance between them and the cage was short (16 cm), and the step-down latencies increased with increasing depths (36.7 ± 7.92 to 185.87 ± 35.44 s). Lesioned rats showed a similar behavior when facing the shortest depth, but had a significantly increased number (23.28 ± 2.35 episodes) and latency (300 ± 0.00 s) of HD compared to normal rats (9.25 ± 1.37 episodes and 185.87 ± 35.44 s) when facing the greatest depth (30 cm). This suggests that HD may be a depth-measuring behavior related to risk assessment.
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Stationary states of an electron in thin GaAs elliptical quantum rings are calculated within the effective-mass approximation. The width of the ring varies smoothly along the centerline, which is an ellipse. The solutions of the Schrödinger equation with Dirichlet boundary conditions are approximated by a product of longitudinal and transversal wave functions. The ground-state probability density shows peaks: (i) where the curvature is larger in a constant-with ring, and (ii) in thicker parts of a circular ring. For rings of typical dimensions, it is shown that the effects of a varying width may be stronger than those of the varying curvature. Also, a width profile which compensates the main localization effects of the varying curvature is obtained.
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A redução do espaço nasofaringeano devido à hipertrofia adenoideana leva a adaptações posturais da cabeça, mandíbula, língua e lábios, podendo causar alterações no padrão esquelético facial. Foram coletadas 98 teleradiografias em norma lateral de pré-adolescentes na faixa etária de 7 a 10 anos na Clínica de Ortodontia da F.O. Araraquara, as quais foram selecionadas levando-se em consideração a dimensão da imagem do espaço nasofaringeano (ENF) (correspondente à menor distância do dorso do palato mole à parede faringeana posterior). As radiografias foram divididas em 3 grupos: Grupo I (estreito), ENF entre 1,7 e 5,1mm; Grupo II (médio), ENF entre 5,2 e 7,6mm; Grupo III (amplo), ENF entre 7,7 e 12,9mm. Utilizamos duas medidas angulares e seis medidas lineares para caracterizar a morfologia facial. As médias e o desvio padrão de cada medida efetuada foram obtidas, e por meio de teste de análise de variância (ANOVA), verificou-se diferença não significativa entre os grupos para as variáveis: ANperp, p=0,07; PgNperp, p=0,058, comprimento mandibular, p=0,15, comprimento maxilar, p=0,06, diferença maxilomandibular, p=0,98, eixo facial, p=0,96, altura facial inferior, p=0,84 e significativa na variável plano mandibular (p<0,01). Portanto, a redução do espaço nasofaringeano está associada a alterações no plano mandibular, que apresentou valores maiores com a diminuição do espaço nasofaringeano.
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Comparative genomic hybridization (CGH) was used to identify chromosomal imbalances in 19 samples of squamous cell carcinoma of the head and neck (HNSCC). The chromosome arms most often or er-represented were 3q (48%), 8q (42%), and 7p (32%); in many cases, these changes were observed at high copy number. Other commonly over-represented sites were 1q, 2q, 6p, 6q, and 18q. The most frequently under-represented segments were 3p and 22q. Loss of heterozygosity of two polymorphic microsatellite loci from chromosome 22 was observed in two tongue tumors, in agreement with the CGH analysis. Gains of 1q and 2q material were detected in patients exhibiting a clinical history of recurrence and/or metastasis followed by terminal disease. This association suggests that gain of 1q and 2q map be a new marker of head and neck tumors with a refractory clinical response. (C) 2000 Elsevier B.V. All rights reserved.
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Purpose: To compare a single intraoperative sub-Tenon's capsule triamcinolone acetonicle injection with steroid drops in the treatment of ocular inflammation after cataract surgery.Design: Randomized, double-masked controlled trial.Participants: A total of 100 patients were randomized prospectively into 2 groups: 50 patients treated with 1% prednisolone eyedrops (control group A) and 50 patients treated with sub-Tenon's capsule triamcinolone (treatment group B).Methods: All patients underwent phacoemulsification and intraocular posterior lens implantation. After surgery, patients were randomized to receive either (group B) an intraoperative 40 mg triamcinolone acetonicle sub-Tenon's capsule injection or (group A) 1% prednisolone acetate eyedrops, according to the following schedule: 1 drop 4 times daily (week 1), 3 times daily (week 2), 2 times daily (week 3), once daily (week 4). To mask the study, group B received vehicle drops administered on a similar schedule, and group A received an intraoperative sub-Tenon's capsule injection of a 1 ml balanced salt solution.Main Outcome Measures: the main outcome measures included inflammation (cell, flare, ciliary flush), intraocular pressure, and lack of response.Results: Triamcinolone was shown to have anti-inflammatory efficacy clinically equivalent to conventional 1% prednisolone eyedrops in reducing intraocular inflammation, as measured by clinical methods. Triamcinolone was found to be as safe as the prednisolone in terms of adverse effects, changes in visual acuity, intraocular pressure, and biomicroscopic and ophthalmoscopic variables. on the third, seventh, fourteenth, and twenty-eighth postoperative days, a significantly lower intraocular pressure (P<0.01) was noted in the triamcinolone group than in the prednisolone group.Conclusions: A single intraoperative 40-mg triamcinolone acetonide sub-Tenon's capsule injection demonstrated a clinically equivalent therapeutic response and ocular tolerance compared with 1% prednisolone drops in controlling postoperative inflammation after uncomplicated cataract surgery and merits further investigation. (C) 2004 by the American Academy of Ophthalmology.
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In populational studies, the weight/width carapace relationship analysis, can furnish indications about the individual physiological variations as a function of the environment, and it can indicate sexual dimorphism. The goal of this research is to find the mathematical expressions of weight/width carapace relationship in the crab Hepatus pudibundus. This study was accomplished by analysing the crabs that were sampled monthly with a shrimp fishing boat equipped with 2 otter-trawl nets, during the period from november/1988 to october/1989. A total of 624 specimens were obtained composed of 244 males and 380 females. In each group the sex, the weight (PE) and the carapace width (LC) were determined. The obtained values agree with the studied range, showing variations during male and female development, represented by the potential function of the equation Y = aX(b). Such variations are probably related to reproductive strategies.
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The superior cervical ganglion (SCG) provides sympathetic input to the head and neck, its relation with mandible, submandibular glands, eyes (second and third order control) and pineal gland being demonstrated in laboratory animals. In addition, the SCG's role in some neuropathies can be clearly seen in Horner's syndrome. In spite of several studies published involving rats and mice, there is little morphological descriptive and comparative data of SCG from large mammals. Thus, we investigated the SCG's macro- and microstructural organization in medium (dogs and cats) and large animals (horses) during a very specific period of the post-natal development, namely maturation (from young to adults). The SCG of dogs, cats and horses were spindle shaped and located deeply into the bifurcation of the common carotid artery, close to the distal vagus ganglion and more related to the internal carotid artery in dogs and horses, and to the occipital artery in cats. As to macromorphometrical data, that is ganglion length, there was a 23.6% increase from young to adult dogs, a 1.8% increase from young to adult cats and finally a 34% increase from young to adult horses. Histologically, the SCG's microstructure was quite similar between young and adult animals and among the 3 species. The SCG was divided into distinct compartments (ganglion units) by capsular septa of connective tissue. Inside each ganglion unit the most prominent cellular elements were ganglion neurons, glial cells and small intensely fluorescent cells, comprising the ganglion's morphological triad. Given this morphological arrangement, that is a summation of all ganglion units, SCG from dogs, cats and horses are better characterized as a ganglion complex rather than following the classical ganglion concept. During maturation (from young to adults) there was a 32.7% increase in the SCG's connective capsule in dogs, a 25.8% increase in cats and a 33.2% increase in horses. There was an age-related increase in the neuronal profile size in the SCG from young to adult animals, that is a 1.6-fold, 1.9-fold and 1.6-fold increase in dogs, cats and horses, respectively. on the other hand, there was an age-related decrease in the nuclear profile size of SCG neurons from young to adult animals (0.9-fold, 0.7-fold and 0.8-fold in dogs, cats and horses, respectively). Ganglion connective capsule is composed of 2 or 3 layers of collagen fibres in juxtaposition and, as observed in light microscopy and independently of the animal's age, ganglion neurons were organised in ganglionic units containing the same morphological triad seen in light microscopy. Copyright (c) 2007 S. Karger AG, Basel.
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Objective: To evaluate the influence of different cross-head speeds on shear bond strength test on the dentin surface.Methods: One hundred and twenty extracted bovine incisors were embedded in polystyrene resin. The specimens were prepared by wet grinding with 320-, 400- and 600-grit Al2O3 paper exposing dentin. After the application of the adhesive system Single Bond (3M) to etched dentin, the composite resin Z-100 (3M) was applied and light cured. The specimens were randomly assigned to four groups (n = 30). The shear bond strength tests were performed with an EMIC DL 500 universal testing machine at four different cross-head speeds: 0.50 (A); 0.75 (B); 1.00 (C); and 5.00 mm/min (D).Results: the mean values of shear bond strength in MPa (SD) were: A, 11.78 (3.91); B, 11.82 (4.78); C, 16.32 (6.45); D, 15.46 (5.94). The data were analyzed with one-way ANOVA and Tukey's test (alpha = 0.05). The results indicated that A = B < C = D. The fracture pattern was evaluated by visual analysis in a stereomicroscope (25 x). The percentage of fractures that occurred at the adhesive interface were: A, 92.5%; B, 91.6%; C, 70.0%; D, 47.0%. The Student's t-test to percentages (
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The aim of this study was to determine the role of head, eye and arm movements during the execution of a table tennis forehand stroke. Three-dimensional kinematic analysis of line-of-gaze, arm and ball was used to describe visual and motor behaviour. Skilled and less skilled participants returned the ball to cued right or left target areas under three levels of temporal constraint: pre-, early- and late-cue conditions. In the pre- and early-cue conditions, both high and low skill participants tracked the ball early in flight and kept gaze stable on a location in advance of the ball before ball-bat contact. Skilled participants demonstrated an earlier onset of ball tracking and recorded higher performance accuracy than less skilled counterparts. The manipulation of cue condition showed the limits of adaptation to maintain accuracy on the target. Participants were able to accommodate the constraints imposed by the early-cue condition by using a shorter quiet eye duration, earlier quiet eye offset and reduced arm velocity at contact. In the late-cue condition, modifications to gaze, head and arm movements were not sufficient to preserve accuracy. The findings highlight the functional coupling between perception and action during time-constrained, goal-directed actions.
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Background. IGF2 and H19 are reciprocal imprinted genes with paternal and maternal monoallelic expression, respectively. This is interesting, because IGF2 is known as a growth factor, and H19 encodes a RNA with putative tumor suppressor action. Furthermore, IGF2 and H19 are linked genes located on chromosome 11p15.5, a common site of loss of heterozygosity in human cancers.Methods. We performed an allelic-typing assay using a PCR-RFLP-based method for identification of heterozygous Informative cases in head and neck squamous cell carcinomas. Tumoral total RNA was extracted from each of the heterozygotes and further studied by RT-PCR analysis.Results. We detected the expression of the IGF2 gene in 10 of 10 informative cases. Two cases exhibited LOI of the IGF2 gene as evidenced by biallelic expression, and in another case, LOH was coupled with monoallelic expression of this growth factor. LOI for the H19 gene was observed in 1 of 14 informative samples analyzed. In this case, we also detected parallel mono-allelic expression of the IGF2 gene. Down-regulation of the H19 gene was observed in 10 of 14 cases.Conclusion. These findings support the hypothesis that H19 may be a tumor suppressor gene involved In head and neck carcinogenesis. Furthermore, our data showed that genetic and epigenetic chances at 11p15.5 could lead to abnormal expression of imprinted genes in HNSCC. (C) 2001 John Wiley & Sons, Inc.