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Looking for a Rarity: Histiocytic Sarcoma
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作者 Joana de Castro Rocha Isabel Paiva Ana Rita Cruz 《Journal of Cancer Therapy》 2016年第2期79-82,共4页
Histiocytic sarcoma is an extremely rare and very aggressive malignancy, with poor prognosis. The cases described in the literature are few and the treatment is not currently considered consensual. The clinical presen... Histiocytic sarcoma is an extremely rare and very aggressive malignancy, with poor prognosis. The cases described in the literature are few and the treatment is not currently considered consensual. The clinical presentation is very variable. Its characterization is made based primarily on the histology. The authors present a case of an 82-year-old woman, with multiple adenopatic retroperitoneal and left iliac conglomerates, with left leg associated edema (extrinsic compression by conglomerates). After intensive study and approach ganglion biopsy, the histologic diagnosis revealed a histiocytic sarcoma. 展开更多
关键词 Histiocytic Sarcoma rarity Aggressive Malignancy LYMPHADENOPATHY
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Local and regional richness and rarity of leaf-litter ants:An overview from spacial scale in neotropical region
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作者 Manoel Fernando Demétrio Rogério Silvestre 《Open Journal of Animal Sciences》 2013年第2期10-15,共6页
An unusual approach about richness and rarity of leaf-litter ant species is presented here from a dry forest reminiscent in Pantanal province (Chacoan subregion) suggesting the boundaries that defining local and regio... An unusual approach about richness and rarity of leaf-litter ant species is presented here from a dry forest reminiscent in Pantanal province (Chacoan subregion) suggesting the boundaries that defining local and regional scales for this particular ant community. We analysed the frequency of distribution of 170 ant species collected on 262 Winkler’s samples along Serra da Bodoquena National Park, Mato Grosso do Sul state, Brazil and described some ecological mechanisms that made the species richness estimates be highly influenced by species with low frequencies of records in an extent regional of a pristine dry forest. Bayesian inference was conducted to provide if the probability of latitudinal gradient was correlated with the species richness to define alpha diversity. 展开更多
关键词 Alpha Diversity FORMICIDAE rarity Patterns Regional Scale
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Using Ecosystem Service Modeler (ESM) for Ecological Quality, rarity and Risk Assessment of the wild goat habitat, in the Haftad-Gholleh protected area 被引量:1
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作者 Amir Ansari Mohammad H.Golabi 《International Soil and Water Conservation Research》 SCIE CSCD 2019年第4期346-353,共8页
In recent years,the destruction of habitats has reduced the wild goat population in the Haftad-Gholleh protected area.The wild goat (Capra aegagrus) is known as symbol of biodiversity of Markazi Province.In a field st... In recent years,the destruction of habitats has reduced the wild goat population in the Haftad-Gholleh protected area.The wild goat (Capra aegagrus) is known as symbol of biodiversity of Markazi Province.In a field study conducted between 2007 and 2017,the number of wild goats were surveyed and threat to their habitat were determined as the population and the ecological conditions as well as their movements in the Haftad-Gholleh were identified.Landsat image of year 2018 was used to produce digital land use maps for this study.Ecological Quality,Rarity and Risk Assessment was performed with ESM,HQR and HRA models.The images were classified into three classes including;Agriculture-livestock,Rangeland,and Residential regions.The results indicated that 75% of the casualties of the wild goat by Peste des Petits Ruminants disease were from the Chekab Valley and 25% from the Sibak Valley.Almost 80% of deaths among the population of wild goats were observed in the month of July.However,there are two important mountainous and plains habitats in the Haftad-Gholleh Area.Among the biggest threats and more devastating stressors in the region were to villagers,agricultural-livestock and roads development.However,among the stressors,the agriculture-livestock caused more deaths in the mountainous habitat of the wild goats.Thus,there is an urgent need for habitat conservation of the existing population of the wild goat in Haftad-Gholleh area. 展开更多
关键词 Haftad-gholleh WILD GOAT (Capra aegagrus) Wildlife disease HABITAT quality and rarity HABITAT risk assessment
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Endoscopic mucosal resection of duodenal bulb adenocarcinoma with neuroendocrine features:An extremely rare case report 被引量:1
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作者 Ming-Yao Wen Yu Wang +1 位作者 Xiao-Yan Meng Hua-Ping Xie 《World Journal of Gastroenterology》 SCIE CAS 2015年第24期7608-7612,共5页
Duodenal adenocarcinoma, especially duodenal bulb with neuroendocrine features(NEF), is extremely rare. Here, we report one such case of duodenal bulb adenocarcinoma with neuroendocrine features. A 63-year-old Han Chi... Duodenal adenocarcinoma, especially duodenal bulb with neuroendocrine features(NEF), is extremely rare. Here, we report one such case of duodenal bulb adenocarcinoma with neuroendocrine features. A 63-year-old Han Chinese woman was admitted to our department with the diagnosis of a duodenal bulb polyp and underwent an endoscopic mucosal resection. The pathological findings confirmed it as duodenal bulb adenocarcinoma with NEF. The patient remains curative after one and half a years of follow-up. Duodenal adenocarcinoma with NEF might be a low malignant neuroendocrine tumor rather than a conventional adenocarcinoma. Endoscopic treatment, including endoscopic mucosal resection, might be an ideal option for the adenocarcinomas with NEF. 展开更多
关键词 DUODENAL ADENOCARCINOMA Neuroendocrinefeatures Endoscopic MUCOSAL resection Duodenalbulb rarity
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The Effect of <i>Miscanthus</i>Cultivation on the Biodiversity of Ground Beetles (Coleoptera: Carabidae), Spiders and Harvestmen (Arachnida: Araneae and Opiliones) 被引量:1
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作者 Michael A. Williams Alan Feest 《Agricultural Sciences》 2019年第7期903-917,共15页
In-crop invertebrate biodiversity of the perennial rhizomatous biomass crop Miscanthus was compared to the in-crop invertebrate biodiversity of adjacent agricultural land-uses. Ground beetles and arachnids (spiders an... In-crop invertebrate biodiversity of the perennial rhizomatous biomass crop Miscanthus was compared to the in-crop invertebrate biodiversity of adjacent agricultural land-uses. Ground beetles and arachnids (spiders and harvestmen) were used as indicators of invertebrate biodiversity and caught using pitfall traps over two years. Biodiversity measurements used were species richness, biomass, abundance, Simpson’s Index, and rarity values. The Miscanthus plantation had a significantly lower ground beetle and arachnid species richness, biomass and abundance than an adjacent mixed-use arable field and a significantly lower ground beetle biomass and abundance than an adjacent grassland. Reduced weed vegetation and lack of insects that feed on Miscanthus are likely to be significant factors. The findings contradict the conclusions of a previous study of Miscanthus impact on butterflies. This is the first major study to assess the in-crop biodiversity of an established plantation and shows that Miscanthus invertebrate biodiversity is poor in established plantations, when compared to adjacent conventional agricultural land-uses. 展开更多
关键词 Biomass Energy Crops BIODIVERSITY Quality Species Richness Simpson’s Index rarity
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Floristic Composition and Diversity of Freshwater Swamp Forests in the Niger Basin of Nigeria
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作者 Nwabueze I. Igu Robert Marchant 《Open Journal of Forestry》 2018年第4期567-584,共18页
Freshwater swamp forests are wetland ecosystems with poorly understood ecology. With increasing degradation across the Niger basin (where it is the most extensive across West Africa), it is deemed important to underst... Freshwater swamp forests are wetland ecosystems with poorly understood ecology. With increasing degradation across the Niger basin (where it is the most extensive across West Africa), it is deemed important to understand its distribution, patterns and composition. This is aimed at both increasing botanical inventories in the ecosystem and also elucidate vital steps that could guide its effective conservation. This study assessed the floristic composition and diversity across 16 one hectare forest plots and sought to show how varied the sites were in terms of diversity, stem density and basal area. The survey showed that the area had 116 species within 82 genera and 36 families. The number of species found in each of the disturbed sites was generally higher than the intact forest sites, which was not diverse but comprised many trees with higher basal area. While the stem density which ranged from 94 - 409 stems·ha-1 is comparable with that of other tropical forests, species richness was low (ranging from 8.65 - 0.52). Diversity ranged from 3.38 - 0.98 and was higher in disturbed sites than in intact locations. Species richness was generally low and implies that loss of species in the ecosystem could threaten species’ existence and conservation in the ecosystem. Disturbed locations had more species than the intact zones and as such show the importance of targeted conservation not only in the undisturbed locations but also in the disturbed locations with a higher species value and potential for species stability of the ecosystem. 展开更多
关键词 BIODIVERSITY Forest Disturbance Species rarity Stem Density TROPICAL FORESTS
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Diversity Dimensions of Freshwater Fish Species around the World
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作者 Carlos Granado-Lorencio Cástor Guisande +7 位作者 Patricia Pelayo-Villamil Ana Manjarrés-Hernández Emilio García-Roselló Juergen Heine Elisa Pérez-Costas Luis González-Vilas Jacinto González-Dacosta Jorge M. Lobo 《Journal of Geographic Information System》 2021年第1期1-18,共18页
The quality and coverage of the available taxonomical and geographical information and the recognition that diversity is multi-faceted are two main factors that hinder to understand the spatial and temporal variations... The quality and coverage of the available taxonomical and geographical information and the recognition that diversity is multi-faceted are two main factors that hinder to understand the spatial and temporal variations of biodiversity. In this study, we aim to quantify the global distribution of five diversity components used to assess freshwater fish diversity in river basins around the world. The multidimensional character of these diversity components was estimated and the so obtained diversity dimensions mapped. This was done taking into account those well-surveyed basins discriminated by considering collector’s curves, and additionally by controlling for the effect of survey effort on all considered diversity components. A total of 1,472,109 occurrence records were analysed, corresponding to 17,292 species of freshwater fishes. Five diversity components were considered: functional richness, species richness, taxonomic diversity, and two rarity measures. Well-surveyed river basins were discriminated using accumulation curves. The effects of survey biases and knowledge gaps were minimized by determining the relationship of each component with the completeness values calculated for each river basin. The geographical pattern derived from raw data is skewed by the unequal knowledge available, and all diversity components were positively correlated with completeness values. The first dimension described the association between species richness and functional diversity. The second dimension represented rarity and taxonomic diversity. The congruence between species richness and functional diversity suggests that ecosystem functions increase with the number of fish species present in river basins and that a decrease in species richness may involve a loss of functionality. The levels of rarity and taxonomic diversity of many species-poor basins found in arid and cold regions suggest that the distinctiveness of their freshwater fishes is primarily a consequence of how isolated these basins are. 展开更多
关键词 Diversity Components Functional Diversity Species Richness rarity Taxonomic Diversity
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The Effect of Willow Short Rotation Coppice Cultivation on the Biodiversity Quality of Ground-Layer Invertebrates
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作者 Michael Alan Williams Alan Feest 《Agricultural Sciences》 2022年第3期378-392,共15页
The biodiversity quality of ground-layer invertebrates within the cropped area of a plantation of the biomass crop willow short-rotation coppice (SRC) grown within a floodplain was compared to the biodiversity quality... The biodiversity quality of ground-layer invertebrates within the cropped area of a plantation of the biomass crop willow short-rotation coppice (SRC) grown within a floodplain was compared to the biodiversity quality of the neighbouring plots of floodplain grassland and a mixed deciduous woodland plantation. Pitfall traps were used to collect ground beetles (Carabidae) and arachnids (Araneae and Opiliones) in the plots over a period of two years. A range of biodiversity indices was used to assess the biodiversity quality of each of the three plots, and the willow SRC was compared to each of the controls using Mann-Whitney tests. The willow SRC transitioned from almost bare ground to young woodland during the two years of the study, which affected comparisons with alternative land uses as the habitat during the second year was very different from the habitat at the start of the study. Compared to plantation woodland, in the first year, the effect was mostly positive, but this declined in the second year. Compared to grassland there was a largely negative effect in both years. However, when in combination with other habitats, willow SRC cultivation on floodplain land may have an overall positive effect on invertebrate biodiversity quality. 展开更多
关键词 Biodiversity Quality BIOMASS Energy Crops rarity Short Rotation Coppice
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Primary Liver Large B-Cell Lymphoma: A Rare Diagnosis
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作者 Joana de Castro Rocha Raquel Lopes +3 位作者 Ana Rita Cruz Cristina Goncalves Joao Araujo Correia Jorge Coutinho 《Open Journal of Blood Diseases》 2015年第1期9-12,共4页
Primary liver lymphoma is extremely rare, in most of cases it is a B cell lymphoma. Usually the diagnosis is made in middle-aged individuals and most of them have a relatively short life expectancy. In this article, t... Primary liver lymphoma is extremely rare, in most of cases it is a B cell lymphoma. Usually the diagnosis is made in middle-aged individuals and most of them have a relatively short life expectancy. In this article, the authors present a case report of a 75-year-old woman with symptoms of three weeks of evolution of diffuse abdominal pain, asthenia and anorexia. The analysis showed cyto cholestasis and the radiological image with lush hepatomegaly because of a large hepatic mass. The patient started chemotherapy and actually is well twenty months after the end of the chemotherapy. 展开更多
关键词 Large B Cell Lymphoma LIVER rarity
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Species abundance distributions as a proxy for the niche-neutrality continuum
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作者 Xianzhi Wang M.D.Farnon Ellwood +2 位作者 Dexiecuo Ai Renyi Zhang Gang Wang 《Journal of Plant Ecology》 SCIE CSCD 2018年第3期445-452,共8页
Aims Species abundance distributions(SADs)are often used to verify mechanistic theories underlying community assembly.However,it is now accepted that SADs alone are not sufficient to reveal biological mechanisms.Recen... Aims Species abundance distributions(SADs)are often used to verify mechanistic theories underlying community assembly.However,it is now accepted that SADs alone are not sufficient to reveal biological mechanisms.Recent attention focuses on the relative importance of stochastic dispersal processes versus deterministic processes such as interspecific competition and environmental filtering.Here,we combine a study of the commonness and rarity of species(i.e.the SAD)with mechanistic processes underlying community composition.By comparing the occurrence frequen-cies of each and every species with its abundance,we quantify the relative contributions of common and rare species to the maintenance of community structure.Essentially,we relate the continuum between commonness and rarity with that of niches and neutrality.Methods An individual-based,spatially explicit model was used to simu-late local communities in niche spaces with the same parameters.We generated sets of assemblages from which species were elim-inated in opposing sequences:from common to rare and from rare to common,and investigated the relationship between the abundance and frequency of species.We tested the predictions of our model with empirical data from a field experiment in the environmentally homogeneous alpine meadows of the Qinghai-Tibetan plateau.Important Findings Our simulations support the widespread notion that common species maintain community structure,while rare species maintain species diversity,in both local and regional communities.Our results,both from theoretical simulations and from empirical observations,revealed positive correlations between the abundance of a particular species and its occurrence frequency.SAD curves describe a continuum between commonness and rarity.Removing species from the‘rare’end of this continuum has little effect on the similarity of communities,but remov-ing species from the‘common’end of the continuum causes significant increases in beta diversity,or species turnover,between communities.In local communities distributed in a homogenous habitat,species located at the‘common’end of the continuum should be selected by environmental filtering,with niche space partitioning governed by interspecific competition.Conversely,species located at the‘rare’end of the continuum are most likely subject to stochastic dispersal pro-cesses.Species situated at intermediate locations on this continuum are therefore determined by niche and neutral processes acting together.Our results suggest that,in homogeneous habitats,SAD curves describ-ing the common-rare continuum may also be used to describe the con-tinuum between niches and neutrality. 展开更多
关键词 rarity COMMONNESS CONTINUUM occurrence frequency community similarities
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Little Designer or Little Actress
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作者 谈铮棋 《小学生时代(大嘴英语)》 2019年第5期F0003-F0003,共1页
Hello, everyone! My name is Rarity. I've got many hobbies, but I love painting the most. Green, grey and orange are nny favorite colors. I wish one day I could be a fashion designer(时尚设计师),just like Coco Chan... Hello, everyone! My name is Rarity. I've got many hobbies, but I love painting the most. Green, grey and orange are nny favorite colors. I wish one day I could be a fashion designer(时尚设计师),just like Coco Chanel(可可·香奈儿). 展开更多
关键词 rarity DESIGNER CHANEL
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