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821.
Fatal primary diffuse large B‐cell lymphoma of the maxillary sinus initially treated as an infectious disease in an elderly patient: A clinicopathologic report 下载免费PDF全文
Mayara Santos de Castro Cínthia Magalhães Ribeiro Marina Lara de Carli Alessandro Antônio Costa Pereira Felipe Fornias Sperandio Oslei Paes de Almeida João Adolfo Costa Hanemann 《Gerodontology》2018,35(1):59-62
Objective
To report a case of primary diffuse large B‐cell lymphoma (DLBCL) of the maxillary sinus in an 82‐year‐old Caucasian woman.Background
Diffuse large B‐cell lymphoma of the maxillary sinus has non‐specific signs and symptoms that may be confused with benign inflammatory conditions and upper respiratory infections.Methods
An incisional biopsy was performed. CD20+/CD3–/Ki‐67: 95% cells were observed.Conclusion
A good medical history, clinical and imaging evaluations and immunohistochemical reactions are crucial to establish a correct and early diagnosis of DLBCL. 相似文献822.
823.
Tarso De Menezes Macedo Costa Nuno Miguel da Silva Ascensão Vaz Álvaro Armindo Dos Santos Rodrigues Ana Isabel De Melo Azevedo Neto José Manuel Viegas Oliveira Neto Azevedo 《Invertebrate reproduction & development.》2018,62(3):169-177
Population biology of the intertidal crabs Pachygrapsus marmoratus Fabricius, 1787 and P. maurus (Lucas 1846) was investigated at cobble beaches with different levels of wave exposure. Surveys were taken monthly over 1.5 years at three intertidal levels. The growth rate of both species was similar, although P. marmoratus reached larger sizes. This species was more abundant on the mid-littoral zone of sheltered beaches, whereas P. maurus was more abundant on more exposed ones. The sex ratio was male biased in both species, particularly for the smaller and larger size classes. Both species showed an extended reproductive season, coinciding with the rising temperatures of spring and summer, with ovigerous females being found from June to September for P. marmoratus and from May to August for P. maurus. The present study indicates that both could develop adaptive strategies allowing them to coexist in the Azores littoral. The greater size of P. marmoratus seems to be an advantage on the competition for refuges with P. maurus, which results in its higher abundance and general dominance in the higher shore levels and in less exposed shores. However, P. maurus seems to be more fitted to live in the higher hydrodynamic habitats. 相似文献
824.
Ana Gabriela de J. Araujo Guillermo O. Obregón Gilvan Sampaio Antonio Miguel V. Monteiro Luiz Tadeu da Silva Balbina Soriano Carlos Padovani Daniel Andres Rodriguez Jelena Maksic José Felipe Silva Farias 《Wetlands Ecology and Management》2018,26(5):829-848
The hydrology of the Brazilian Pantanal, part of the largest humid tropical area on the planet, follows the rhythm of seasonal floods. The traditional movement of cattle herds in the southern Pantanal is defined by these seasonal flooding patterns, which determine the availability and quality of native-grass pastures throughout the year. Extreme hydrological events, such as prolonged droughts and intense floods, can impact the management of cattle in this region, preventing access to, circulation within, and occupation of some grazing areas. This study aims to analyze the spatial and temporal variability of precipitation, the river levels in this region from 1974 to 2012, and assessed the effects on the evolution of local beef cattle stocks. We integrated the spatiotemporal variability of precipitation and river levels for six gaging stations and standardized these variables using standard deviation and linear trends at annual and seasonal scales. Additionally, we integrated the results with an analysis of the livestock production within the region’s municipalities. Regional precipitation was highly variable, including an almost decadal oscillation, with positive trends in parts of the 1970s and 1980s and a negative trend since the 1990s. River levels in the northern portion of the basin and in the Paraguay River corresponded to those dynamics while presenting marked anomalies. Simultaneously, river levels in the eastern Pantanal changed from negative to positive anomalies, which were more intense in wet months. Both the eastern and western patterns reflected the occurrence of extreme El Niño–Southern Oscillation events and other large-scale climatic patterns. In intra-annual terms, the variability of the river levels during the flooded months at four of the six gaging stations studied suggests an early onset or delay of the flood season, as well as positive anomalies in the ebbing months and in the southeast. Given the lags in flow between different rivers in the region, this behavior draws attention to dam construction and intensification of localized flooding in the southern areas, which may impact everyday life and cattle management. For example, from 2009 to 2012, two severe droughts and an extreme flood significantly impacted livestock numbers in the region. Overall, herd numbers decreased (increased) in humid (dry) periods, including a reduction of over 1 million head during the flood of 1973–1974. The differential level patterns at annual, wet season, and dry season between the eastern and western sides of the Pantanal modulate the livestock activities, where the strong negative anomalies of the levels along the eastern side seem to force the diminution of beef cattle stock at local regions in different intensities in annual scale. This reinforces the effects of climate variability and extreme hydrological events on the management and dynamics of the beef cattle industry and market in Brazil. 相似文献
825.
C2‐symmetric sulfonamides as homogeneous and heterogeneous organocatalysts that mimic enzymes in enantioselective Michael additions 下载免费PDF全文
Harold Cruz Felipe A. Servín Domingo Madrigal Daniel Chávez Sergio Perez‐Sicairos Gerardo Aguirre Andrew L. Cooksy Ratnasamy Somanathan 《Chirality》2018,30(8):1036-1044
Herein, we report the synthesis of C2‐symmetric sulfonamides as homogeneous and heterogeneous organocatalysts and their application in the enantioselective conjugate 1,4‐Michael addition of carbonylic nucleophiles to β‐nitrostyrene. Organocatalysts hydrogen bond to β‐nitrostyrene and enamine in the transition state, mimicking an enzyme leading to final products in high yields (up to 98%) and good enantioselectivities (up to 96%). In addition, these results were supported by density functional calculations. 相似文献
826.
Maria Angeles Martinez-Grau Isabel C. Gonzalez Valcarcel Julie V. Early Richard Klaus Gessner Candice Soares de Melo Eva Maria Martin de la Nava Aaron Korkegian Yulia Ovechkina Lindsay Flint Anisa Gravelle Jeff W. Cramer Prashant V. Desai Leslie J. Street Joshua Odingo Thierry Masquelin Kelly Chibale Tanya Parish 《Bioorganic & medicinal chemistry letters》2018,28(10):1758-1764
Despite increased research efforts to find new treatments for tuberculosis in recent decades, compounds with novel mechanisms of action are still required. We previously identified a series of novel aryl-oxadiazoles with anti-tubercular activity specific for bacteria using butyrate as a carbon source. We explored the structure activity relationship of this series. Structural modifications were performed in all domains to improve potency and physico-chemical properties. A number of compounds displayed sub-micromolar activity against M. tuberculosis utilizing butyrate, but not glucose as the carbon source. Compounds showed no or low cytotoxicity against eukaryotic cells. Three compounds were profiled in mouse pharmacokinetic studies. Plasma clearance was low to moderate but oral exposure suggested solubility-limited drug absorption in addition to first pass metabolism. The presence of a basic nitrogen in the linker slightly increased solubility, and salt formation optimized aqueous solubility. Our findings suggest that the 1,3,4-oxadiazoles are useful tools and warrant further investigation. 相似文献
827.
Yago Moises Larrat Francisco Tiago de Vasconcelos Melo Tássia Fernanda Furo Gomes Yuri Wilkens Jeannie Nascimento dos Santos 《Systematic parasitology》2018,95(8-9):871-879
Leptodactylus paraensis Heyer, is a Neotropical anuran species that inhabits Rainforest habitats in the eastern Amazon, but because it has only been recently separated from the Leptodactylus pentadactylus (Laurenti) species group, little is known about its helminth fauna. This study describes a new species of Oswaldocruzia Travassos, 1917 and records the first occurrence of this genus parasitising L. paraensis and the second species for the Caxiuanã National Forest in the eastern Amazon, Brazil. Oswaldocruzia lanfrediae n. sp. is characterised by having an anterior extremity with a smooth cephalic vesicle divided into two portions, a claviform oesophagus, well-developed cuticular longitudinal ridges and lateral alae. Females have a well-developed ovojector, with didelphic and amphidelphic uteri. Males show complex robust spicules divided into a slightly curved shoe, a bifurcated fork and a blade terminating in 2–3 processes. The new species differs from its congeners especially regarding the lateral alae and the morphology of the spicules, in addition to morphometric characters such as body size, oesophagus length, deirid position, nerve-ring position and relative position of the vulva in females. 相似文献
828.
Ritha Kov Marta Camps-Arbestain Roberto Calvelo Pereira Manuel Suárez-Abelenda Qinhua Shen Stanislav Garbuz Felipe Macías Vázquez 《Biogeochemistry》2018,140(1):65-79
Andisols are characterised by having abundant reactive Al in the form of short-range ordered (SRO) Al constituents and organo-Al complexes, which facilitates the accumulation of soil organic matter (OM). However, recent studies of New Zealand pastoral systems have reported loss of carbon (C) from Andisols when under intense management. This study compares the organic and inorganic chemistry of Andisols on two adjacent pasture sites under different pastoral management regimes (Paddock 2 being more intensively managed than Paddock 1), as well as under a nearby pine stand (Forest). Mean soil pH-H2O in Forest (5.3) was significantly lower (P?<?0.05) than that in Paddock 1 (5.7), which itself was significantly lower (P?<?0.05) than in Paddock 2 (6.1). Soil C concentrations were significantly higher (P?<?0.05) in the soils under pasture than under pine (63.8 g C/kg), and C in Paddock 1 (98.1 g C/kg) was significantly higher (P?<?0.05) than in Paddock 2 (84.1 g C/kg). The ratio of Al in organo-Al complexes (as estimated with sodium pyrophosphate) to the sum of Al in both SRO and organo-Al complexes (Alp/Alo) was significantly smaller (P?<?0.05) as the alkalinity of the soils increased (0.38, 0.23, 0.16 for Forest, Paddock 1 and Paddock 2, respectively). At the molecular level, soils under Forest had a larger relative contribution of degraded products of plant polysaccharides than those under pasture, while these had a larger contribution of fresh (e.g. cellulose and cutan/suberan aliphatic structures) and N-rich OM (e.g., microbial fingerprints, denoting a high microbial activity). Dissolved organic C content in the rhizosphere of pasture species was similar between paddocks, but Paddock 2 had a significantly (P?<?0.05) greater contribution of organic acids of MW?<?500 Da and higher pH (6.8 vs. 6.2). The results (1) confirm the common enrichment in organic C of New Zealand top soils under pasture compared to those under pine, and (2) reveal that the changes in the soil chemistry associated with pasture management may weaken the ability of these soils to preserve OM. 相似文献
829.
830.
Jesús Pérez-Serrano Edans Sandes Alba Cristina Magalhaes Alves de Melo Manuel Ujaldón 《BMC bioinformatics》2018,19(14):421