873 resultados para Perfectly Plastic


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Thirty-one patients with unilateral long-standing facial palsy underwent I-stage reanimation with free gracilis muscle transplant innervated by the masseteric branch of the trigeminal nerve. They were divided into 2 nonrandomized groups according to insertion technique: group 1 (9 patients), interrupted suture between the free flap and the orbicularis oris of the upper and lower lip on the paralyzed side; group It (22 patients), palmaris longus tendon graft placed between the gracilis free flap and the orbicularis oris of the upper and lower lip on the nonparalyzed side. Qualitative evaluation of the smile demonstrated better results in patients from group II. Comparing the position Of the Cupid`s bow at rest, pre- and postoperatively in each patient, we observed significant improvement of facial symmetry in both groups. During smile, however, there was a significantly higher rate of centralization of the Cupid`s bow in patients submitted to reanimation with the use of the palmaris longus tendon (group II).

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Despite modern reanimation surgical techniques, facial paralysis presents with functional and aesthetic deficits. We evaluated facial symmetry after treating with botulinum toxin the healthy side of the face of 25 patients with long-standing facial paralysis who had previously been treated by surgical methods, with 6 months follow-up. Evaluation consisted of a clinical score, the two subscales of the Facial Disability Index, and surface electromyography. The mean botulinum toxin dose was 38 +/- A 5 U (range = 15-69 U). The clinical score showed significant reduction of asymmetry of 48.4% at 1 month and 16.8% after 6 months. The initial result was a consequence of reduced motion on the treated side combined with better motion on the paralyzed side. At 6 months, the treated side returned to basal scores. The residual effect seen in symmetry was due to an increase (18%) of motion in the paralyzed side. There was a significant decrease in the action potential of muscles on the nonparalyzed side 1 month post injection but completely reverted after 6 months. The Physical Function Index increased, but not significantly. The Social/Well-Being Function Index showed a significant increase at 6 months compared to pretreatment. The proposed treatment improved facial symmetry for up to 6 months. Even after the end of the clinical effect of the drug, the paralyzed side`s clinical score was 18% higher than pretreatment, with an increased quality of life.

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Protrusion of the abdominal wall secondary to abdominoplasty may occur in patients with weakness of the aponeurotic structures. The anterior layer of the rectus abdominis muscle consists of fibers that are transverse rather than vertical. Based on this anatomical feature, vertical sutures are suggested for the correction of diastasis recti, since they include a greater amount of fascial fibers and thus would be more resistant to tensile strength than horizontal ones. The anterior layers of the rectus abdominis muscles of 15 fresh cadavers were dissected. Two vertical lines were marked on each side of the linea alba, corresponding to the site where plication is usually performed in abdominoplasties. Three abdominal levels were evaluated: the supraumbilical, umbilical, and infraumbilical levels. A simple suture was placed in the vertical direction in one group and in the horizontal direction in the other group, at each of the three levels previously described. These sutures were connected to a dynamometer, which was pulled medially toward the linea alba until rupture of the aponeurosis occurred. The mean strength required to rupture the aponeurotic structures in which the vertical sutures had been placed was greater than for the horizontal ones (p < 0.0001). The vertical suture of the rectus abdominis sheaths was stronger than the horizontal suture because of the more transversal arrangement of its aponeurotic fibers. Thus, routine use of the vertical suture in plications of the aponeurosis of the rectus abdominis muscles is suggested.

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Background: Although the role of cartilage grafts in reconstruction of the posterior eyelid lamella is well established, spontaneous conjunctival epithelialization on such grafts has yet to be fully proven. The aim of this study was to perform a comparative analysis of the influence of perichondrium on conjunctival epithelialization over conchal cartilage grafts used in eyelid reconstruction in rabbits. Methods: The posterior lamellae of 100 lower eyelids from 50 rabbits were reconstructed with autogenous grafts of conchal ear cartilage. In the right eyelids, cartilage was grafted with the perichondrium in direct contact with the eyeball, and the left eyelids were reconstructed in a similar manner but using cartilage grafts without perichondrium. The animals were killed after 1, 2, 3, 4, and 5 weeks, and their lower eyelids were analyzed macroscopically and histologically. Results: The percentage difference in conjunctival epithelialization on the cartilage with perichondrium and that without perichondrium was 11.41 percent in the first week of the experiment, 13.64 percent in the second week, 18.69 percent in the third week, 10.38 percent in the fourth week, and 6.17 percent in the fifth week. The average percentage conjunctival epithelialization in the eyelids reconstructed with a cartilage graft with perichondrium was significantly higher throughout the 5 weeks of the experiment than in the eyelids reconstructed with cartilage without perichondrium (p < 0.0002). Conclusion: It was found that the perichondrium had an important role in conjunctival epithelialization in eyelids reconstructed with a cartilage graft in the present study. (Plast. Reconstr. Surg. 123: 55, 2009.)

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Background: Tessier no. 4 facial cleft is a rare, complex, and challenging craniofacial malformation. The present article aims to describe different clinical features evidenced in 21 cases of this malformation, discussing a 20-year experience with and evolution of its surgical treatment. Methods: Some demographic data, clinical features, and reconstructive results were evaluated retrospectively. These patients have been evaluated and treated in three specialized Brazilian craniofacial centers. Nineteen were already operated on, with a mean follow-up of 3.5 years (range, 1 to 20 years). Results: Sex distribution showed a male prevalence (2: 1). The average age of initial treatment was 5.4 years. Four cases were affected on the right side of the face, seven on the left, and 10 bilaterally. Six patients had other rare associated facial clefts, including nos. 5 (three patients), 7, 9, and 10. Cleft upper lip was evidenced in all patients, and maxillary hypoplasia was present in five and maxilla cleft in eight. Lower eyelid coloboma was seen in almost every case (19 patients); 10 of these had medial canthus dystopia. Four patients had amniotic bands in the limbs. Surgical repair was individualized to each patient. Surgical experience gained with these patients allowed the authors to develop some technical modifications, which have improved aesthetic results, camouflaging scars into natural folds and anatomical units, without compromising functional outcomes. Conclusions: The great majority of Tessier no. 4 facial clefts can be appropriately treated using local flaps. Classic techniques are extremely useful, but long-term results could be improved if the technical modifications described were adopted. (Plast. Reconstr. Surg. 122: 1505, 2008.)

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The search for an ideal filler for soft tissue augmentation still continues. Because aging changes are continuous, temporary fillers should be preferred against permanent ones. Since 1999, the poly-L-lactic acid filler (PLA) has been marketed in Europe as Newfill. As a synthetic biocompatible polymer, PLA originally was used in suture materials and screws. In 2004, the U.S. Food and Drug Administration approved PLA under the name of Sculptra for the treatment of human immunodeficiency virus-related facial lipoatrophy. This study aimed to evaluate a 3-year follow-up investigation into the effect of PLA implant injection for the treatment of sunken nasolabial folds. Between October 2003 and February 2004, 10 women with a median age of 54 years (range, 43-60 years) were injected with polylactic acid hydrogel (Newfill) in the nasolabial fold area for aesthetic reasons. All the patients underwent three injections: one injection per month for 3 months. Evaluation of the results based on clinical examination and photography was performed at each session, at 6 months, and then 36 months after the third session. Injectable PLA was able to correct nasolabial folds successfully with a more lasting result than absorbable fillers commonly used in clinical practice, such as hyaluronic acid and collagen. Careful and standardized photographic documentation is indispensable.

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Purlin-sheeting systems used for roofs and walls commonly take the form of cold-formed channel or zed section purlins, screw-connected to corrugated sheeting. These purlin-sheeting systems have been the subject of numerous theoretical and experimental investigations over the past three decades, but the complexity of the systems has led to great difficulty in developing a sound and general model. This paper presents a non-linear elasto-plastic finite element model, capable of predicting the behaviour of purlin-sheeting systems without the need for either experimental input or over simplifying assumptions. The model incorporates both the sheeting and the purlin, and is able to account for cross-sectional distortion of the purlin, the flexural and membrane restraining effects of the sheeting, and failure of the purlin by local buckling or yielding. The validity of the model is shown by its good correlation with experimental results. A simplified version of this model, which is more suitable for use in a design environment, is presented in a companion paper. (C) 1997 Elsevier Science Ltd.

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A number of theoretical and experimental investigations have been made into the nature of purlin-sheeting systems over the past 30 years. These systems commonly consist of cold-formed zed or channel section purlins, connected to corrugated sheeting. They have proven difficult to model due to the complexity of both the purlin deformation and the restraint provided to the purlin by the sheeting. Part 1 of this paper presented a non-linear elasto plastic finite element model which, by incorporating both the purlin and the sheeting in the analysis, allowed the interaction between the two components of the system to be modelled. This paper presents a simplified version of the first model which has considerably decreased requirements in terms of computer memory, running time and data preparation. The Simplified Model includes only the purlin but allows for the sheeting's shear and rotational restraints by modelling these effects as springs located at the purlin-sheeting connections. Two accompanying programs determine the stiffness of these springs numerically. As in the Full Model, the Simplified Model is able to account for the cross-sectional distortion of the purlin, the shear and rotational restraining effects of the sheeting, and failure of the purlin by local buckling or yielding. The model requires no experimental or empirical input and its validity is shown by its goon con elation with experimental results. (C) 1997 Elsevier Science Ltd.

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Stem cells (SC) are potential therapeutic tools in the treatment of chronic renal diseases. Number and engraftment of SC in the injured sites are important for possible differentiation into renal cells and paracrine effect. The aim of this study was to analyze the effect of subcapsular injection of mesenchymal stem cells (MSC) in the 5/6 nephrectomy model (5/6 Nx). MSC obtained from Wistar rats were isolated by their capacity to adhere to plastic surfaces, characterized by flow cytometry, and analyzed by their differentiation potential into osteoblasts. MSC (2 X 105) were injected into the subcapsule of the remnant kidney of male Wistar rats, and were followed for 15 or 30 days. 5/6 Nx rats showed significant hypertension at 15 and 30 days, which was reduced by MSC at 30 days. Increased albuminuria and serum creatinine at 15 and 30 days in 5/6 Nx rats were also reduced by subcapsular injection of MSC. We also observed a significant reduction of glomerulosclerosis index 30 days after injection of MSC. 4-6 diamidino-2-phenylindole dihydrochloride (DAPI)-stained MSC showed a migration of these cells into renal parenchyma 5, 15, and 30 days after subcapsular injection. In conclusion, our data demonstrated that subcapsular injection of MSC in 5/6 Nx rats is associated with renoprotective effects. These results suggest that locally implanted MSC in the kidney allow a large number of cells to migrate into the injured sites and demonstrate that subcapsular injection represent an effective route for MSC delivery.

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The fluorescence spectrum of a strongly driven two-level atom located inside an optical cavity damped by a narrow-bandwidth squeezed vacuum is studied. We use a dressed atom model approach, first applied to squeezed vacuum problems by Yeoman and Barnett, to derive the master equation of the system and discuss the role of the cavity and the squeezed vacuum in the narrowing of the spectral lines and the population trapping effect. We find that in the presence of a single-mode cavity the effect of squeezing on the fluorescence spectrum is more evident in the linewidths of the Rabi sidebands rather than in the linewidth of the central component. Even in the absence of squeezing, the cavity can reduce the linewidth of the central component almost to zero, whereas the Rabi sidebands can be narrowed only to some finite value. In the presence of a two-mode cavity and a two-mode squeezed vacuum the signature of squeezing is evident in the linewidths of all spectral lines. We also establish that the narrowing of the spectral lines is very sensitive to the detuning of the driving field from the atomic resonance. Moreover, we find that the population trapping effect, predicted for the broadband squeezed vacuum case, may appear in a narrow-bandwidth case only if the input squeezed modes are perfectly matched to the cavity modes and if there is non-zero squeezing at the Rabi sidebands.

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This investigation focused on the finite element analyses of elastic and plastic properties of aluminium/alumina composite materials with ultrafine microstructure. The commonly used unit cell model was used to predict the elastic properties. By combining the unit cell model with an indentation model, coupled with experimental indentation measurements, the plastic properties of the composites and the associated strengthening mechanism within the metal matrix material were investigated. The grain size of the matrix material was found to be an important factor influencing the mechanical properties of the composites studied. (C) 1997 Elsevier Science S.A.

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The level of incident radiation and the proportion of radiation that is diffuse affects radiation use efficiency (RUE) in crops, However, the degree of this effect, and its importance to growth and yield of sunflower (Helianthus annuus L.) have not been established. A field experiment was conducted to investigate the effects of radiation environment on RUE, growth, and yield of sunflower. A fully irrigated crop was sown on an alluvial-prairie soil (Fluventic Haplustoll) and was exposed to three distinct radiation environments. In two treatments, the level of incident radiation was reduced by 14 and 20% by suspending tao different types of polyethylene plastic films well above the crop. In addition to the reductions in incident radiation, the proportion of radiation that was diffuse was increased by about 14% in these treatments. Lower incident radiation and increased proportion of diffuse radiation had no effect on total biomass, phenology, leaf area, and the canopy light extinction coefficient (k = 0.89). However, yield was reduced in shaded treatments due to smaller grain size and lower harvest index. Although crop RUE measured over the entire crop cycle (1.25 g/MJ) did not differ significantly among treatments, there was a trend where RUE compensated for less intercepted incident radiation. Theoretical derivations of the response of RUE to different levels of incident radiation supported this finding. Shaded sunflower crops have the ability to produce biomass similar to unshaded crops by increasing RUE, but have lower harvest indices.

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Purpose: The objective of this pilot study was to evaluate the efficacy and safety of 5% imiquimod cream in the treatment of periocular basal cell carcinoma (BCC) through the analysis of a case series. Methods: Eight subjects with primary nodular BCC of the eyelid were recruited. Treatment lasted 10 to 16 weeks. The average follow-up time was 11.7 months. Results: Of a total of 10 lesions, 80% resolved clinically and histologically and have remained asymptomatic since. Conclusion: Imiquimod cream 5% was shown to be an attractive alternative to surgical treatment of periocular BCC. Future studies with larger samples and longer follow-up periods are expected to provide more accurate information on the efficacy and safety of the drug.

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Background: Although various techniques have been used for breast conservation surgery reconstruction, there are few studies describing a logical approach to reconstruction of these defects. The objectives of this study were to establish a classification system for partial breast defects and to develop a reconstructive algorithm. Methods: The authors reviewed a 7-year experience with 209 immediate breast conservation surgery reconstructions. Mean follow-up was 31 months. Type I defects include tissue resection in smaller breasts (bra size A/B), including type IA, which involves minimal defects that do not cause distortion; type III, which involves moderate defects that cause moderate distortion; and type IC, which involves large defects that cause significant deformities. Type II includes tissue resection in medium-sized breasts with or without ptosis (bra size C), and type III includes tissue resection in large breasts with ptosis (bra size D). Results: Eighteen percent of patients presented type I, where a lateral thoracodorsal flap and a latissimus dorsi flap were performed in 68 percent. Forty-five percent presented type II defects, where bilateral mastopexy was performed in 52 percent. Thirty-seven percent of patients presented type III distortion, where bilateral reduction mammaplasty was performed in 67 percent. Thirty-five percent of patients presented complications, and most were minor. Conclusions: An algorithm based on breast size in relation to tumor location and extension of resection can be followed to determine the best approach to reconstruction. The authors` results have demonstrated that the complications were similar to those in other clinical series. Success depends on patient selection, coordinated planning with the oncologic surgeon, and careful intraoperative management.

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Oncoplastic Breast Surgery (OPBS) is becoming an integral part of breast cancer management, but few surgeons have received formal training in these techniques. An International Symposium has recently debated the key issues which impact on training and specialisation in OPBS, as well as patient access to these procedures. The Symposium concluded that increasing the availability of OPBS is a major challenge, which demands much closer collaboration and cooperation between breast and plastic surgeons, backed up by new training schemes, new curricula and new guidelines. (C) 2010 Elsevier Ltd. All rights reserved.