195 resultados para Himantura Fai Dasyatididae


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The monogeneans Decacotyle lymmae and D. tetrakordyle (Monocotylidae: Decacotylinae), from gills of the dasyatid stingrays Taeniura lymma and Pastinachus sephen, respectively, have a single aperture for adhesive secretion on each side of the anterior ventrolateral region. Rod-shaped bodies (S1) and electron-dense spherical secretion (S2) exit through specialised ducts opening adjacent to one another within these apertures. The S1 bodies are 230 +/- 11 nm wide and greater than or equal to4 mum long in D. lymmae and 240 +/- 9 nm wide and greater than or equal to3.3 mum long in D. tetrakordyle. The S2 bodies have a diameter of 88 +/- 7 nm in D. lymmae and 65 +/- 6 nm in D. tetrakordyle. The apertures are unusual in being extremely small (internal diameter, 3-5 mum). Each aperture has a slit-like surface opening as small as 160 nm wide, surrounded by muscle fibres indicating that they may be opened and closed. The aperture is also surrounded and underlain by muscle fibres that may aid in secretion from, or even eversion of, the tissue within the aperture. Sensilla/cilia are also found within the apertures. Additional secretions from anteromedian and anterolateral glands (body glands), each containing granular secretions, occur in profusion and exit anteriorly and posteriorly to the position of the apertures, through duct openings in the general body tegument. These granular secretions do not appear to be associated with anterior adhesion. Both species show similarities in aperture, underlying tissue, sense organ, and secretion detail, in accordance with findings from other monogenean genera, and which supports the importance of such data for phylogenetic studies.

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The anterior adhesive system of the oncomiracidium and adult of Merizocotyle icopae (Monogenea: Monocotylidae) were compared. The oncomiracidium has one ventrally placed aperture on either side of the head near the anterior extremity. In the adult, there are three ventrally placed apertures on either side of the head region. Both systems have three types of electron-dense secretory bodies opening into each aperture. A rod-shaped secretion (S1) and a small electron dense ovoid secretion (S2) are common to larvae and adults. The third secretion type differs: in adults, it is a large, spherical (S3) type but in larvae, it is an ovoid (S4) body. S4 bodies do occur in adults, but appear to be secreted as a general body secretion. An additional anteromedian secretion (S5) is also present in the oncomiracidium, but is not secreted into the anterior apertures. Homology and function of secretions are discussed.

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Monogeneans (flatworms) are among the most host-specific of parasites in general and may be the most host-specific of all fish parasites. Specificity, in terms of a restricted spatial distribution within an environment, is not unique to parasites and is displayed by some fungi, insects, birds, symbionts and pelagic larvae of free-living marine invertebrates. The nature of cues, how habitats are recognised and how interactions between partners are mediated and maintained is of interest across these diverse associations. We review some experiments that demonstrate important factors that contribute to host-specificity at the level of infective stages (larvae of oviparous monogeneans; juveniles of viviparous gyrodactylids) and adult parasites. Recent research on immune responses by fish to monogenean infections is considered. We emphasise the critical importance of host epidermis to the Monogenea. Monogeneans live on host epidermis, they live in its products (e.g. mucus), monopisthocotyleans feed on it, some of its products are attractants and it may be an inhospitable surface because of its immunological activity. We focus attention on fish but reference is made to amphibian hosts. We develop the concept for a potential role in host-speciality by the anterior adhesive areas, either the specialised tegument and/or anterior secretions produced by monogeneans for temporary but firm attachment during locomotion on host epithelial surfaces. Initial contact between the anterior adhesive areas of infective stages and host epidermis may serve two important purposes. (1) Appropriate sense organs or receptors on the parasite interact with a specific chemical or chemicals or with surface structures on host epidermis. (2) A specific but instant recognition or reaction occurs between component(s) of host mucus and the adhesive(s) secreted by monogeneans. The chemical composition of fish skin is known to be species-specific and our preliminary analysis of the chemistry of some monogenean adhesives indicates they are novel proteins that display some differences between parasite families and species. (C) 2000 Australian Society for Parasitology Inc. Published by Elsevier Science Ltd. All rights reserved.

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Patterns of movement in aquatic animals reflect ecologically important behaviours. Cyclical changes in the abiotic environment influence these movements, but when multiple processes occur simultaneously, identifying which is responsible for the observed movement can be complex. Here we used acoustic telemetry and signal processing to define the abiotic processes responsible for movement patterns in freshwater whiprays (Himantura dalyensis). Acoustic transmitters were implanted into the whiprays and their movements detected over 12 months by an array of passive acoustic receivers, deployed throughout 64 km of the Wenlock River, Qld, Australia. The time of an individual's arrival and departure from each receiver detection field was used to estimate whipray location continuously throughout the study. This created a linear-movement-waveform for each whipray and signal processing revealed periodic components within the waveform. Correlation of movement periodograms with those from abiotic processes categorically illustrated that the diel cycle dominated the pattern of whipray movement during the wet season, whereas tidal and lunar cycles dominated during the dry season. The study methodology represents a valuable tool for objectively defining the relationship between abiotic processes and the movement patterns of free-ranging aquatic animals and is particularly expedient when periods of no detection exist within the animal location data.

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The population’s life expectancy is growing every year. This fact highlights the importance of the elderly for the dentistry. The oral cavity quality has great influence on quality of life at both the biological and the psychological and social factors by maintaining a self-esteem, self-expression, communication and satisfactory facial aesthetics. Unfortunately, the number of edentulous elderly population is also high, which may create problems to their social life. Therefore, the objective of this study was to demonstrate and evaluate the difficulties of treating edentulous patients, comparing data prior to treatment to post data after treatment by complete dentures made to the patients undergoing oral rehabilitation in the Dental Clinic of the Faculty of Dentistry of Adamantina – FAI. For this study, questionnaires were filled in the form of answers developed alternative focused on the degree of patient satisfaction, the current situation of occlusion, and outcome of treatment. The results showed that 96% of patients were satisfied with the results obtained in the treatment, all of whom believed that the prosthesis helped them feel better aesthetically and improved self-esteem. By this methodology, it was concluded that the degree of satisfaction was high, but the services provided must be constantly reevaluated, once the elderly population presents a wide labor market for dental professionals and demand level services will certainly increase each year.

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Dal 1936 al 1939 la Spagna dovette fare i conti con gli orrori di una guerra che aveva diviso in due il paese, sia ideologicamente che geograficamente, facendogli vivere una tragedia ancora oggi tangibile nel tessuto sociale e politico della penisola iberica. Questo conflitto, che aveva suscitato l’interesse di molti, raggiunse un livello tale di sperimentazione, sia in campo militare, sia in quello civile, da essere considerato un banco di prova per la seconda guerra mondiale. Il progetto di tesi, attraverso l’analisi e il sottotitolaggio di due documentari, uno anarchico e l’altro franchista, intende presentare una ricerca che ha come focus primario lo studio della propaganda cinematografica durante il periodo della guerra civile spagnola. Il cinema che, proprio negli anni Trenta, si era definitivamente affermato anche grazie all’introduzione del sonoro, fu presto considerato un potente mezzo di comunicazione divenendo un’arma di persuasione della quale, entrambi gli schieramenti con tempistiche diverse, si servirono per indottrinare la popolazione e giustificare la propria azione militare. Il cinema, pertanto, fu messo al servizio della guerra. Nel primo capitolo di questo elaborato verrà presentato il quadro storico di riferimento con la definizione delle cause, dell’evoluzione e delle ideologie in campo durante il conflitto. Il secondo capitolo si concentrerà sull’analisi dei due sistemi di propaganda, quella repubblicana e quella nazionalista, con un’attenzione principale nei confronti della propaganda cinematografica e delle sue diverse espressioni politiche nella penisola iberica. In questo capitolo si farà, inoltre, accenno alla produzione cinematografica internazionale riferita al conflitto spagnolo durante gli anni della guerra e in quelli immediatamente successivi. Infine, nel terzo e ultimo capitolo, si prenderanno in analisi i due documentari sottotitolati (“Los Aguiluchos de la FAI por tierras de Aragón, Reportaje nº1, Estampas de la revolución antifascista” e “La Liberación de Madrid”, con la presentazione dell’analisi tecnica e contenutistica degli stessi. Per concludere, verranno indicate le strategie traduttive impiegate durante la fase di traduzione e riportati esempi concreti ad esse riferite.

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The Bernese periacetabular osteotomy (PAO) is a popular option for treating symptomatic acetabular dysplasia. We noted symptomatic impingement after PAO in several male patients.

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To define the feasibility of utilizing T2* mapping for assessment of early cartilage degeneration prior to surgery in patients with symptomatic femoroacetabular impingement (FAI), we compared cartilage of the hip joint in patients with FAI and healthy volunteers using T2* mapping at 3.0 Tesla over time.

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OBJECTIVES: To study the three-dimensional (3D) T1 patterns in different types of femoroacetabular impingement (FAI) by utilizing delayed gadolinium-enhanced magnetic resonance imaging (MRI) of cartilage (dGEMRIC) and subsequent 3D T1 mapping. We used standard grading of OA by Tonnis grade on standard radiographs and morphological grading of cartilage in MRI for comparative analysis. METHODS: dGEMRIC was obtained from ten asymptomatic young-adult volunteers and 26 symptomatic FAI patients. MRI included the routine hip protocol and a dual-flip angle (FA) 3D gradient echo (GRE) sequence utilizing inline T1 measurement. Cartilage was morphologically classified from the radial images based on the extent of degeneration as: no degeneration, degeneration zone measuring <0.75 cm from the rim, >0.75 cm, or total loss. T1 findings were evaluated and correlated. RESULTS: All FAI types revealed remarkably lower T1 mean values in comparison to asymptomatic volunteers in all regions of interest. Distribution of the T1 dGEMRIC values was in accordance with the specific FAI damage pattern. In cam-types (n=6) there was a significant drop (P<0.05) of T1 in the anterior to superior location. In pincer-types (n=7), there was a generalized circumferential decrease noted. High inter-observer (intra-observer) reliability was noted for T1 assessment using intra-class correlation (ICC):intra-class coefficient=0.89 (0.95). CONCLUSIONS: We conclude that a pattern of zonal T1 variation does seem to exist that is unique for different sub-groups of FAI. The FA GRE approach to perform 3D T1 mapping has a promising role for further studies of standard MRI and dGEMRIC in the hip joint.

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The purpose of this study was to assess if delayed gadolinium MRI of cartilage using postcontrast T(1) (T(1Gd)) is sufficient for evaluating cartilage damage in femoroacetabular impingement without using noncontrast values (T(10)). T(1Gd) and DeltaR(1) (1/T(1Gd) - 1/T(10)) that include noncontrast T(1) measurements were studied in two grades of osteoarthritis and in a control group of asymptomatic young-adult volunteers. Differences between T(1Gd) and DeltaR(1) values for femoroacetabular impingement patients and volunteers were compared. There was a very high correlation between T(1Gd) and DeltaR(1) in all study groups. In the study cohort with Tonnis grade 0, correlation (r) was -0.95 and -0.89 with Tonnis grade 1 and -0.88 in asymptomatic volunteers, being statistically significant (P < 0.001) for all groups. For both T(1Gd) and DeltaR(1), a statistically significant difference was noted between patients and control group. Significant difference was also noted for both T(1Gd) and DeltaR(1) between the patients with Tonnis grade 0 osteoarthritis and those with grade 1 changes. Our results prove a linear correlation between T(1Gd) and DeltaR(1), suggesting that T(1Gd) assessment is sufficient for the clinical utility of delayed gadolinium MRI of cartilage in this setting and additional time-consuming T(10) evaluation may not be needed.

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Femoroacetabular impingement (FAI) is an established cause of osteoarthrosis of the hip. Surgery is intended to remove the cause of impingement with hip dislocation and resection of osseous prominences of the acetabular rim and of the femoral head-neck junction. Using the Merle d'Aubigné score and qualitative categories, recent studies suggest good to excellent outcomes in 75% to 80% of patients after open surgery with dislocation of the femoral head. Unsatisfactory outcome is mainly related to pain, located either in the area of the greater trochanter or in the groin. There are several reasons for persisting groin pain. Joint degeneration with joint space narrowing and/or osteophyte formation, insufficient correction of the acetabula, and femoral pathology are known factors for unsatisfactory outcome. Recently, intraarticular adhesions between the femoral neck and joint capsule have been identified as an additional cause of postoperative groin pain. The adhesions form between the joint capsule and the resected area on the femoral neck and may lead to soft tissue impingement. MR-arthrography is used for diagnosis and the adhesions can be treated successfully by arthroscopy. While arthroscopic resection improves outcome it is technically demanding. Avoiding the formation of adhesions is important and is perhaps best accomplished by passive motion exercises after the initial surgery.