998 resultados para Citologia Aspirativa por Agulha Fina
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JUSTIFICATIVA E OBJETIVOS: Complicações neurológicas da anestesia subaracnóidea, apesar de raras, podem determinar seqüelas importantes. O objetivo deste estudo é apresentar estas complicações com a finalidade de esclarecer os fatores desencadeantes, o que facilita o diagnóstico das lesões. CONTEÚDO: São apresentadas as seguintes complicações: lesão de nervo desencadeada pela agulha e cateter, cefaléia pós-punção, síndrome da artéria espinhal anterior, hematoma espinhal, meningite bacteriana, meningite asséptica, aracnoidite adesiva, síndrome da cauda eqüina e sintomas neurológicos transitórios. CONCLUSÕES: O conhecimento dos fatores desencadeantes de complicações neurológicas determinadas pela anestesia subaracnóidea pode prevenir as lesões, diagnosticar e tratar mais precocemente e, desse modo, mudar o prognóstico das mesmas.
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JUSTIFICATIVA E OBJETIVOS: O número de artroplastia total de quadril (ATQ) bilateral tem aumentado a cada ano. Analgesia pós-operatória pela infusão contínua perineural com anestésico local tem se mostrado favorável quando comparada com analgesia sistêmica. O uso de bombas elastoméricas tem aumentado a satisfação do paciente quando em comparação com os modelos eletrônicos. O objetivo deste relato foi descrever um caso de analgesia contínua bilateral do plexo lombar via posterior, com infusão contínua através de bomba elastomérica, em paciente submetido à uma artroplastia bilateral de quadril. RELATO do CASO: Paciente feminina, 46 anos, 65 kg, 162 cm, com artrite reumatoide e hipertensão arterial, estado físico ASA II, escalada para ser submetida a ATQ bilateral em um único estágio. Uso de corticosteroide por 13 anos. Hemoglobina = 10,1 g.dL-1, hematócrito = 32,7%. Monitoração de rotina. Raquianestesia com 15 mg de bupivacaína 0,5% isobárica. Anestesia geral com propofol (PFS) e remifentanil e intubação sem bloqueadores neuromusculares. ATQ direita e no final, bloqueio plexo lombar com estimulador e conjunto agulha 150 mm e injeção de 20 mL bupivacaína 0,2% e passagem de cateter. ATQ esquerda e, no final, mesmo procedimento. Estudado dispersão do anestésico e contraste. Instalado bomba elastomérica com bupivacaína 0,1% (400 mL) em velocidade de 14 mL.h-1. Transferida para Unidade de Cuidados Intensivos (UCI). Vinte e quatro horas após, nova bomba com a mesma solução. Nenhum bolus durante 50 horas. Após remoção de cateter, dor controlada por via oral com cetoprofeno e dipirona. CONCLUSÕES: O bloqueio bilateral contínuo periférico com infusão de bupivacaína a 0,1% com bombas elastoméricas é um procedimento seguro e efetivo em adultos.
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JUSTIFICATIVA E OBJETIVOS: A raquianestesia unilateral pode apresentar vantagens em pacientes ambulatoriais. O objetivo deste trabalho foi comparar a raquianestesia unilateral com o bloqueio combinado femoral-isquiático em cirurgias ortopédicas unilaterais e ambulatoriais. MÉTODO: Sessenta pacientes foram aleatoriamente separados em dois grupos para receber 6 mg de bupivacaína hiperbárica ou hipobárica (grupo RQ) em decúbito lateral esquerdo ou 800 mg de lidocaína 1,6% com epinefrina nos nervos femoral e isquiático (grupo CFI) em decúbito dorsal. O bloqueio dos nervos foi realizado com agulha de 150 mm conectada a um neuroestimulador e inserida no ponto médio entre as duas abordagens clássicas, sendo injetados 15 mL no nervo femoral e 35 mL no nervo isquiático. Avaliados o tempo para realização dos bloqueios e sua duração. Vinte minutos após, os pacientes foram avaliados em relação aos bloqueios sensitivo e motor. RESULTADOS: O tempo para a realização da raquianestesia foi significativamente menor do que o bloqueio combinado femoral-isquiático. O bloqueio unilateral foi obtido em 90% dos pacientes no grupo RQ e 100% no grupo CFI. O tempo para recuperação do bloqueio sensitivo e motor foi significativamente maior no grupo CFI. Não houve bradicardia ou hipotensão. CONCLUSÕES: Este estudo conclui que é tecnicamente fácil realizar bloqueio anterior combinado femoral-isquiático e pode ser uma alternativa para o bloqueio unilateral do membro inferior. A raquianestesia unilateral com baixas doses de bupivacaína resultou em menor tempo para realização, menor número de tentativas e recuperação mais precoce do bloqueio combinado femoral-isquiático, porém com mesma efetividade.
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Software Products Lines (SPL) is a software engineering approach to developing software system families that share common features and differ in other features according to the requested software systems. The adoption of the SPL approach can promote several benefits such as cost reduction, product quality, productivity, and time to market. On the other hand, the SPL approach brings new challenges to the software evolution that must be considered. Recent research work has explored and proposed automated approaches based on code analysis and traceability techniques for change impact analysis in the context of SPL development. There are existing limitations concerning these approaches such as the customization of the analysis functionalities to address different strategies for change impact analysis, and the change impact analysis of fine-grained variability. This dissertation proposes a change impact analysis tool for SPL development, called Squid Impact Analyzer. The tool allows the implementation of change impact analysis based on information from variability modeling, mapping of variability to code assets, and existing dependency relationships between code assets. An assessment of the tool is conducted through an experiment that compare the change impact analysis results provided by the tool with real changes applied to several evolution releases from a SPL for media management in mobile devices
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OBJETIVO: Determinar a prevalência de pneumonia nosocomial nas autópsias em um hospital público universitário; identificar os fatores de risco relacionados à pneumonia nosocomial e os potenciais fatores prognósticos relacionados à ocorrência de pneumonia nosocomial fatal; e correlacionar os achados anatomopatológicos com a ocorrência de pneumonia nosocomial e/ou pneumonia aspirativa. MÉTODOS: Estudo retrospectivo de 199 pacientes autopsiados, maiores de 1 ano de idade, internados no Hospital das Clínicas da Faculdade de Medicina de Botucatu da Universidade Estadual Paulista entre 1999 e 2006, cuja causa de morte (causa básica ou associada) foi pneumonia nosocomial. Testou-se a associação dos dados demográficos, clínicos e anatomopatológicos com os desfechos pneumonia nosocomial fatal e pneumonia aspirativa fatal. As variáveis significativas entraram na análise multivariada. RESULTADOS: A idade média foi de 59 ± 19 anos. A prevalência de pneumonia nosocomial em autópsias foi 29%, e essa foi a causa mortis de 22,6% dos pacientes autopsiados. A pneumonia nosocomial fatal correlacionou-se com os achados anatomopatológicos de alterações estruturais tabágicas (OR = 3,23; IC95%: 1,26-2,95; p = 0,02) e acometimento pulmonar bilateral (OR = 3,23; IC95%: 1,26-8,30; p = 0,01). Não houve associações significativas entre as variáveis e pneumonia aspirativa fatal. CONCLUSÕES: em nossa amostra, a pneumonia nosocomial teve prevalência elevada e foi responsável por quase 25% das mortes. A mortalidade é favorecida por alterações estruturais tabágicas e pneumonia bilateral. Esses achados corroboram os resultados de diversos estudos clínicos sobre pneumonia nosocomial.
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As síndromes mielodisplásicas são reconhecidas como doenças que se originam nas células-tronco da medula óssea e que requerem avaliação sistemática e criteriosa de sangue periférico e medula óssea para seu correto diagnóstico. O objetivo deste relato é estabelecer os critérios morfológicos (cito-histológicos) como parâmetros para o diagnóstico de SMD em amostras de sangue periférico e medula óssea, com especial direcionamento aos hematologistas e patologistas clínicos que exercem a hematologia laboratorial na sua rotina de trabalho. Os principais achados morfológicos são listados no final deste relato, na forma de check-list, objetivando a sistematização sobre estes achados.
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This thesis describes the general behavior of the northern shore of the State of Rio Grande do Norte relating beach profile morphology with hydrodynamic and sedimentological parameters. The Macau and Serra Oil Field are inserted on this area and are under accelerated coastal erosion. At these oil fields are installed oil wells from PETROBRAS, nowadays located directly in the shoreline, under constant attacks of coastal processes (e.g. waves, tides and currents), which promote an intense morphodynamic variability of this sandy coast. The area was monitored for 24 months in three different stations (P01, P02 and P03). The methodology applied involved current techniques of beach profiles, hydrodynamical processes, remote sensing and geophysics. A synthesis of results obtained through the use of different time scales (monthly, lunar cycle, seasonal, annual) from a coastal dynamics study is presented. The average wind direction corresponded to 77ºAz (NE). The steepness of the berm and of the shoreface, as well as coastal current direction, do not present major changes, with an average of 36º for the steepness of the berm, 15º for the shoreface and 15º for the coastal current direction. This data set allows us to infer that the months of larger coastal erosion were November/2000 and April/2001, because of the largest wave parameter during this time. The months of worse coastal erosion in this area are related with the increasing wavy energy. This in turn, seems to be related to seasonal climatic variations, with the wave energy and tide currents speed increasing during months of minor precipitations (June to January). The months of worse coastal erosion were September and November, when the largest wave parameters and speed currents are measured in the area. Since these months are included on the period of minor precipitations, we related the coastal erosion to seasonal climatic variations. The results obtained during these 24 months of monitoring confirms a situation of accentuated erosion, mainly in Profile 03 (Barra do Corta-Cachorro), where the wave height, period, and coastal current speed are always larger than the values found in Profile 02 (Macau5). Probably these values are more expressive in Profile 03, because it does not present any natural structure of protection against the wave impacts, as the barrier island located at Ponta do Tubarão, or the sand banks in front of Macau5. The transport of the sediments occurs from East to West, and the sand accumulation is more pronounced on Profile 03 intertidal zone, where there are embrionary dunes in dryer months. The tidal currents speed, on the other hand, is more accentuated in the Macau5 area (Profile 02). At Ponta do Tubarão, the tidal currents presented a preferential direction for NE, at times of flood, currents and for NW, at times of ebb current; at Barra do Corta-Cachorro the direction of the currents were predominantly for NW, independent of the tide phase, coinciding with the preferential direction of the longshore current. This currents inversion at Ponta do Tubarão is attributed to the presence of the Ponta do Tubarão island barrier and by the communication channel of the lagoon with the sea. The tide currents are better observed in protected areas, as in the Ponta do Tubarão, when they present inversion in their direction accordingly to the flood and ebb tide. In open areas, as in Barra do Corta-Cachorro, the tide currents are overprinted by the longshore currents. Sediment analysis does not show important modifications in grain size related to seasonality (dry- and rainy seasons). On the foreshore and backshore zones, the sediments vary from fine to medium sand, while in the shoreface they very from fine to very sands. The grains are mostly spheres, varying from sub rounded to sub angled. Quartz is the main component alongside Feldspat and heavy minerals as accessory components. Biogenic content is also present and mainly represented by mollusks fragments. The calculated sediment transport show values around 100 m3/day. The morphodynamic studies indicated that this is a reflexive area from October to April, and intermediate from May to September. The Relative Tide Range-RTR for this area is 4 < RTR < 15, and so classified in the mixed wave-tide group. Having this exposed we can affirm that the more active natural factors in this area are the currents, followed by the tides and the winds. The anthropic factors are exclusively local and punctual (Macau and Serra Oil Field). Taking in account the economic importance of the area, as well as the intensity of coastal processes acting on this shore, it is important a continuity of the monthly environmental monitoring looking for variations on longer-period cycles. These data have been stored on the geo-referenced database of the projects MARPETRO and PETRORISCO (REDE 05), aiming to model the coastal and sea environment, susceptible to oil spills and their derivatives
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The area studied forms a thin NNE-directed belt situated south of Recife town (Pernambuco state), northeastern Brazil. Geologically, it comprises the Pernambuco Basin (PB), which is limited by the Pernambuco Lineament to the north, the Maragogi high to the south and the Pernambuco Alagoas massif to the west, all of them with Precambrian age. This thesis reports the results obtained for the Cabo Magmatic Province (CMP), aiming the characterization of the geology, stratigraphy, geochronology, geochemistry and petrogenesis of the Cretaceous igneous rocks presented in the PB. The PB is composed of the Cabo Formation (rift phase) at the base (polymictic conglomerates, sandstones, shales), an intermediate unit, the Estiva Formation (marbles and argillites), and, at the top, the Algodoais Formation (monomictic conglomerates, sandstones, shales). The CMP is represented by trachytes, rhyolites, pyroclastics (ignimbrites), basalts / trachy-andesites, monzonites and alkali-feldspar granite, which occur as dykes, flows, sills, laccoliths and plugs. Field observations and well descriptions show that the majority of the magmatic rocks have intrusive contacts with the Cabo Formation, although some occurrences are also suggestive of synchronism between volcanism and siliciclastic sedimentation. 40Ar/39Ar and zircon fission tracks for the magmatic rocks indicate an average age of 102 r 1 Ma for the CMP. This age represents an expressive event in the province and is detected in all igneous dated materials. It is considered as a minimum age (Albian) for the magmatic episode and the peak of the rift phase in the PB. The 40Ar/39Ar dates are about 10-14 Ma younger than published palynologic ages for this basin. Geochemically, the CMP may be divided in two major groups; i) a transitional to alkaline suite, constituted by basalts to trachy-andesites (types with fine-grained textures and phenocrysts of sanidine and plagioclase), trachytes (porphyrytic texture, with phenocrysts of sanidine and plagioclase) and monzonites; ii) a alkaline suite, highly fractionated, acidic volcano-plutonic association, formed by four subtypes (pyroclastic flows ignimbrites, fine-to medium-grained rhyolites, a high level granite, and later rhyolites). These four types are distinguished essentially by field aspects and petrographic and textural features. Compatible versus incompatible trace element concentrations and geochemical modeling based on both major and trace elements suggest the evolution through low pressure fractional crystallization for trachytes and other acidic rocks, whereas basalts / trachy-andesites and monzonites evolved by partial melting from a mantle source. Sr and Nd isotopes reveal two distinct sources for the rocks of the CMP. Concerning the acidic ones, the high initial Sr ratios (ISr = 0.7064-1.2295) and the negative HNd (-0.43 to -3.67) indicate a crustal source with mesoproterozoic model ages (TDM from 0.92 to 1.04 Ga). On the other hand, the basic to intermediate rocks have low ISr (0.7031-0.7042) and positive HNd (+1.28 to +1.98), which requires the depleted mantle as the most probable source; their model ages are in the range 0.61-0.66 Ga. However, the light rare earth enrichment of these rocks and partial melting modeling point to an incompatible-enriched lherzolitic mantle with very low quantity of garnet (1-3%). This apparent difference between geochemical and Nd isotopes may be resolved by assuming that the metasomatizing agent did not obliterate the original isotopic characteristics of the magmas. A 2 to 5% partial melting of this mantle at approximately 14 kbar and 1269oC account very well the basalts and trachy-andesites studied. By using these pressure and temperatures estimates for the generation of the basaltic to trachy-andesitic magma, it is determined a lithospheric stretching (E) of 2.5. This E value is an appropriated estimate for the sub-crustal stretching (astenospheric or the base of the lithosphere?) region under the Pernambuco Basin, the crustal stretching probably being lower. The integration of all data obtained in this thesis permits to interpret the magmatic evolution of the PB as follows; 1st) the partial melting of a garnet-bearing lherzolite generates incompatible-enriched basaltic, trachy-andesitic and monzonitic magmas; 2nd) the underplating of these basaltic magmas at the base of the continental crust triggers the partial melting of this crust, and thus originating the acidic magmas; 3rd) concomitantly with the previous stage, trachytic magmas were produced by fractionation from a monzonitic to trachy-andesitic liquid; 4th) the emplacement of the several magmas in superficial (e.g. flows) or sub-superficial (e.g. dykes, sills, domes, laccoliths) depths was almost synchronically, at about 102 r 1 Ma, and usually crosscutting the sedimentary rocks of the Cabo Formation. The presence of garnet in the lherzolitic mantle does not agree with pressures of about 14 kbar for the generation of the basaltic magma, as calculated based on chemical parameters. This can be resolved by admitting the astenospheric uplifting under the rift, which would place deep and hot material (mantle plume?) at sub-crustal depths. The generation of the magmas and their subsequent emplacement would be coupled with the crustal rifting of the PB, the border (NNE-SSW directed) and transfer (NW-SE directed) faults serving as conduits for the magma emplacement. Based on the E parameter and the integration of 40Ar/39Ar and palynologic data it is interpreted a maximum duration of 10-14 Ma for the rift phase (Cabo Formation clastic sedimentation and basic to acidic magmatism) of the PB
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The Curimataú estuary is located in the oriental coast of Rio Grande do Norte State in Brazil. Its importance resides in the fact that this region possesses one of the last portions of preserved mangrove in the Rio Grande do Norte State. Nevertheless, it has been severely affected by many anthropogenic activities, as sugarcane monoculture and shrimp farming. Former works demonstrated that an accumulation of heavy metals is occurring in oysters in this estuary, and perhaps it could be explained by the input of metals in this ecosystem deriving from the shrimp farming. To better understanding the origin of these metals, bottom sediment samples, cores and suspended particulate matter were collected for a characterization of metal concentrations (Al, Ba, Cd, Cu, Cr, Fe, Mn, Ni, Pb, Zn) and to determine the potentially bioavailable metals. Additionally, the enrichment ratio for each element analyzed was calculated. The mineralogical composition of sediment samples and cores were obtained by X-ray diffraction. Moreover, data of orbital remote sensing were used in order to detect and quantify suspended matter by applying a logarithmic algorithm. Geochemical data of bottom sediments and cores revealed that, excepting Ba and Pb, the elements analyzed presented concentrations characteristic of an unpolluted ecosystem (Al: 0,25 - 8,76 %; Ba: 3,03 - 870 µg.g-1; Cd: < 0,25 µg.g-1; Cr: 1,72 - 82,4 µg.g-1; Cu: 0,12 -25,3 µg.g-1; Pb: 0,38 - 23,7 µg.g-1; Fe: 0,10 - 5,82 %; Mn: 15,1 - 815 µg.g-1; Ni: 0,14 - 36,1 µg.g-1; Zn: 1,37 - 113 µg.g-1). During the dry season a distribution pattern was observed, with higher metal concentrations in the margins, decreasing toward the central portion of the channel. These metal concentrations were well correlated with mineralogical compositions, with clay minerals prevailing at the margins, and quartz and feldspar in the center. However, this pattern was not observed during the wet season, probably because of the high water flux that disturbed bottom sediments. But, as observed for the dry season, a good correlation between metal concentrations and mineralogical composition was also observed for the wet season, with high metal concentrations where there were high quantities of clay minerals. Low enrichment ratios were obtained for the majority of elements analyzed, excepting for Mn, Ba and Pb. Manganese presented the higher ratios downstream for both seasons, and it can be an evidence of anthropogenic impact by shrimp farming. As barium and lead concentrations in sediment samples presented analytical problems during the total sample digestion, one cannot be sure that the ratios obtained correspond to the reality. The highest metal concentrations in particulate matter were obtained in the portion dominated by fluvial transport for all metals analyzed, excepting for copper. Barium and zinc were the only elements that presented elevated concentrations that are not common of unpolluted ecosystems (Ba: 5730 - 8355 µg.g-1; Zn: 3899 - 4348 µg.g-1). However, these high concentrations could not be related to the shrimp farming and waste waters from the town of Canguaretama, once they were obtained from the fluvial particulate matter, that is upstream from the activities above mentioned. The application of the logarithmic algorithm to the processed LANDSAT image was well succeeded, although the acquired image does not correspond exactly to the field campaigns. The IKONOS image provided very detailed views of the suspended sediment concentration at the estuary, as the mixture of distinct water flows at the confluence of Cunhaú and Curimataú rivers, with more turbid waters from Cunhaú river, that is directly affected by effluents from shrimp farming and urban waste waters deriving from the town of Canguaretama
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As miopatias em equinos são classificadas de acordo com aspectos clínicos, morfológicos e moleculares, em três grandes grupos: não associadas ao exercício, associadas ao exercício e devido alteração da condução elétrica do sarcolema. Apesar dos avanços no diagnóstico, a literatura ainda relata surtos de miopatia em equinos sem etiologia esclarecida em diversos países. O objetivo desse estudo foi descrever as alterações histológicas e histoquímicas de biópsias musculares de equinos acometidos por miopatia. Sete equinos da raça Quarto de Milha, com 18-24 meses de idade, apresentaram sinais clínicos de miopatia. Dentre esses animais, cinco apresentaram sinais subagudos leves a moderados e dois apresentaram sinais hiperagudos severos e decúbito lateral. Foram realizadas biópsias musculares utilizando a técnica percutânea, por agulha tipo Bergström, no músculo glúteo médio em todos os animais acometidos. As amostras foram processadas por meio de técnicas histológicas (HE, Tricrômio de Gomori modificado) e histoquímicas (PAS, NADH, ATPase). Nos quadros clínicos mais leves, a principal alteração encontrada foi a presença de fibras vermelhas rajadas do tipo I e IIA, que estão associadas às alterações do metabolismo oxidativo e das funções mitocondriais, como ocorrem nas miopatias mitocondriais. Também foram observadas fibras atróficas do tipo I e IIA, além da presença de agregados subsarcolemais. Nos quadros mais severos o tecido muscular apresentou infiltrado inflamatório, aumento de colágeno, fagocitose, necrose, calcificação e regeneração muscular. Diante dos achados morfológicos, da resposta à terapia com vitamina E e Se e da baixa mortalidade quando comparado aos relatos de miopatia atípica, conclui-se que esse surto foi desencadeado por lesões mitocondriais, caracterizadas pelas fibras musculares vermelhas rajadas, possivelmente devido uma quebra da homeostase de vitamina E e Se, sendo compatível com o diagnóstico de miopatia nutricional.
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CONTEXTO E OBJETIVO: A biópsia da próstata não é um procedimento isento de riscos. Existe preocupação com respeito às complicações e quais seriam os melhores antibióticos usados antes do procedimento. O objetivo foi determinar a taxa de complicações e os possíveis fatores de risco para complicação na biópsia da próstata. TIPO DE ESTUDO E LOCAL: Estudo prospectivo clínico, realizado no Hospital das Clínicas de Botucatu. MÉTODOS: Foram realizadas biópsias em 174 pacientes que apresentavam anormalidade ao exame digital da próstata ou antígeno prostático específico maior que 4 ng/ml ou ambos. Todos os pacientes realizaram enema e antibioticoprofilaxia previamente ao exame. As complicações foram anotadas após o término do procedimento e em consultas posteriores. Algumas condições foram investigadas como possíveis fatores de risco para biópsias de próstata: idade, câncer da próstata, diabetes melito, hipertensão arterial sistêmica, antecedentes de prostatite, uso de ácido acetilsalicílico, volume prostático, número de biópsias e uso de sonda vesical. RESULTADOS: As complicações hemorrágicas foram mais comuns (75,3%) enquanto que as infecciosas ocorreram em 19% dos casos. O tipo mais freqüente foi a hematúria, ocorrendo em 56% dos pacientes. A infecção do trato urinário ocorreu em 16 pacientes (9,2%). Sepse foi observada em três pacientes (1,7%). Não houve óbitos. em 20% dos pacientes não foram observadas complicações após o exame. A presença da sonda vesical foi fator de risco para complicações infecciosas (p < 0,05). O número maior de amostras nas biópsias foi relacionado à hematúria, sangramento retal e complicações infecciosas (p < 0,05). As demais condições investigadas não se relacionaram com complicações pós-biópsia da próstata. CONCLUSÕES: As complicações pós-biópsia da próstata foram em sua maioria autolimitadas. A taxa de complicações graves foi baixa, sendo a biópsia de próstata guiada pelo ultra-som segura e eficaz. A retirada de um maior número de fragmentos na biópsia relaciona-se com hematúria, sangramento retal e complicações infecciosas. A sonda vesical foi um fator de risco para complicações infecciosas.
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Ataques por piranhas vêm se tornando um problema comum em trechos represados de rios e córregos no estado de São Paulo, Sudeste do Brasil. em dois surtos ocorridos em dois municípios vizinhos no noroeste do estado, 74 banhistas foram mordidos. Uma mordida por pessoa foi registrada, em curto período do ano. As mordidas estão relacionadas a cuidado parental e/ou defesa do território de desova, o que reforça estudos anteriores e desmistifica os ataques por este peixe lendário, da maneira como são popularmente percebidos. A colocação de redes de malha fina e a remoção de vegetação aquática cessaram os ataques.
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O presente trabalho tem como objetivo investigar as características de filmes de SnO2 depositados em substrato de vidro borosilicato por um processo de silk-screen modificado para obtenção de espessura fina compatível com a aplicação em células solares policristalinas de baixo custo. O filme de SnO2 é um dos mais apropriados para obtenção de vidro TCO (transparent conductive oxide) para uso em células solares devido a sua baixa resistividade elétrica e alta transmitância, sendo quimicamente inerte, mecanicamente duro e tem resistência a altas temperaturas, o que facilita então a calcinação das amostras entre 500º C a 550º C. Os filmes foram obtidos a partir de uma solução precursora básica, preparada pela dissolução de SnCl2.2H2O em Etanol (99,5 %). Foi realizado um planejamento fatorial 2(3-1) para analisar a influência dos parâmetros concentração da solução precursora (CETN), temperatura de calcinação (TC) e taxa de aquecimento (tX) na calcinação, sendo a concentração CETN o parâmetro que apresentou maior efeito sobre os parâmetros de respostas investigados: espessura do filme (ω), resistividade de superfície (ρ) e a transmitância relativa (θ). Foi possível obter com a metodologia utilizada, filmes com espessuras da ordem de 1 Nm com resistividade de superfície de 10 / e transmitância relativa entre 70 e 80 %.
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The studied area is geologically located in the Northern Domain of the Borborema Province (Northeast Brazil), limited to the south by the Patos shear zone. Terranes of the Jaguaribeano system are dominant, flanked by the Piranhas (E and S sides) and Central Ceará (NE side) terranes. Its basement comprises gneiss -migmatite terrains of Paleoproterozoic to Archean age (2.6 to 1.9 Ga old), overprinted by neoproterozoic to cambrian tectonotherma l events. Narrow supracrustal belts ( schist belts) display a 1.6 to 1.8 Ga age, as shown by whole - rock Rb-Sr and zircon U-Pb and Pb/Pb dates in acid metavolcanics which dominate in the lower section of these sequences, and in coeval metaplutonics (granitic augen gneisses). From the stratigraphic point of view, three Staterian belts are recognized: 1. Orós Belt - made up by the Orós Group, subdivided in the Santarém (predominantly pure to impure quartzites, micaschists and metacarbonates) and Campo Alegre (metandesites, metabasalts, metarhyolites and metarhyodacites, interlayered with metatuffs and metasediments) formations, and by the Serra do Deserto Magmatic Suite (granitic augen gneisses). 2. Jaguaribe Belt - its lithostratigrahic-lithodemic framework is similar to the one of the Orós Belt, however with a greater expression of the volcano -plutonic components (Campo Alegre Formation and Serra do Deserto Magmatic Suite). The Peixe Gordo Sequence, separately described, is also related to this belt and contain s metasedimentary, metavolcanic (with subordinated volcanoclastics) and metaplutonic units. The first one correlated to the Orós Group and the latter the Serra do Deserto Magmatic Suite. 3. Western Potiguar Belt - represented by the Serra de São José Gro up, subdivided in the Catolezinho (biotite -amphibole gneisses with intercalations of metacarbonates, calcsilicate rocks, amphibolites and quartzite beds to the top) and Minhuins (quartzites, micaschists, metaconglomerates, calcsilicate rocks, acid to the b asic metavolcanics and metatuffs) formations. Its late Paleoproterozoic (Staterian) age was established by a Pb/Pb date on zircons from a granitic orthogneiss of the Catolezinho Formation. The petrographic characteristics and sedimentary structures of the Santarém Formation of the Orós Group point to deltaic to shallow marine depositional systems, overlain by deep water deposits (turbidites). The geodynamic setting of this region encompassed a large depositional basin, probably extending to the east of the Portalegre shear zone and west of the Senador Pompeu shear zone, with possible equivalents in the Jucurutu Formation of the Seridó Belt and in the Ceará Group of central Ceará. The Arneiróz Belt, west Ceará, displays some stratigraphic features and granito ids geochemically akin to the ones of the Orós Belt. The evolutionary setting started with an extensional phase which was more active in the eastern part of this domain (Western Potiguar and part of the Jaguaribe belts), where the rudite and psamite sedime ntation relates to a fluviatile rift environment which evolved to a prograding deltaic system to the west (Orós Group). The basaltic andesitic and rhyolitic volcanics were associated to this extensional phase. During this magmatic event, acid magmas also crystallized at plutonic depths. The Orós Group illustrates the environmental conditions in the western part of this domain. Later on, after a large time gap (1.6 to 1.1 Ga), the region was subjected to an extensional deformational episode marked by 900 Ma old (Sm-Nd data) basic rocks, possibly in connection with the deposition of the Cachoeirinha Group south of the Patos shear zone. In the 800 to 500 Ma age interval, the region was affected by important deformational and metamorphic events coupled with in trusion of granitic rocks of variable size (dykes to batholiths), related to the Brasiliano/Pan -African geotectonic cycle. These events produced structural blocks which differentiate, one from the other, according to the importance of anatectic mobilizatio n, proportion of high-grade supracrustals and the amount of neoproterozoic -cambrian granitoid intrusions. On this basis, a large portion of the Jaguaretama Block/Terrane is relatively well preserved from this late overprint. The border belts of the Jagua retama Block (Western Potiguar and Arneiroz) display kyanite-bearing (medium pressure) mineral associations, while in the inner part of the block there is a north-south metamorphic zoning marked by staurolite or sillimanite peak metamorphic conditions. Regarding the deformations of the Staterian supracrustal rocks, second and third phases were the most important, diagnosed as having developed in a progressive tectonic process. In the general, more vigorous conditions of PT are related to the interval tardi - phase 2 early-phase 3, whose radiometric ages and regional structuring indicators places it in the Brasiliano/Pan-African Cycle. In the Staterian geodynamic setting of Brazilian Platform , these sequences are correlated to the lower Espinhaço Supergroup (p.ex., Rio dos Remédios and Paraguaçu groups, a paleproterozoic rift system in the São Francisco Craton), the Araí and Serra da Mesa groups (north of Goiás, in the so -called Goiás Central Massif), and the Uatumã Group (in the Amazonian Craton). Granitic ( augen gneisses) plutonics are also known from these areas, as for example the A-type granites intrusive in the Araí and Serra da Mesa groups, dated at 1.77 Ga. Gravimetric and geological data place the limits of the Jaguaribeano System (terranes) along the Senador Pompeu Shear Zone (western border) and the Portalegre- Farias Brito shear zone (eastern and southern). However, the same data area not conclusive as regards the interpretation of those structures as suture of the terrane docking process. The main features of those shear zones and of involved lothological associations, appear to favour an intracontinental transpressional -transcurrent regime, during Neoproterozoic-Cambrian times, marking discontinuities along which different crustal blocks were laterally dispersed. Inside of this orogenic system and according to the magnetic data (total field map), the most important terrane boundary appears to be the Jaguaribe shear zone. The geochronological data, on some tectonostratigraphic associations (partly represented by the Ceará and Jucurutu groups), still at a preliminary level, besides the lack of granitic zonation and other petrotectonic criteria, do not allow to propose tectonic terrane assembly diagrams for the studied area