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排序方式: 共有192条查询结果,搜索用时 31 毫秒
1.
Neuza Domingues André R. A. Marques Rita Diogo Almeida Calado Inês S. Ferreira Cristiano Ramos José Ramalho Maria I. L. Soares Telmo Pereira Luís Oliveira José R. Vicente Louise H. Wong Inês C. M. Simões Teresa M. V. D. Pinho e Melo Andrew Peden Cláudia Guimas Almeida Clare E. Futter Rosa Puertollano Winchil L. C. Vaz Otília V. Vieira 《Traffic (Copenhagen, Denmark)》2023,24(7):284-307
2.
Adiaspiromycosis was identified in 6 animals in the examination of the lungs of 90 large carnivores. Emmonsia crescens (Chrysosporium parvum var. crescens) was demonstrated as the causative agent in 5 cases of disease — in the badger (Meles meles), the otter (Lutra lutra) and the fox (Vulpes vulpes). E. parva was demonstrated in the remaining case of disease in a fox. The badger is a new, up to the present unknown host of E. crescens. The sporadic occurrence of adiaspiromycosis in the fox and the otter classifies this disease among rare diseases of these animals. 相似文献
3.
Fernanda Hurbath BÁrbara SimÕes Santos Leal Otávio Luis Marques Da Silva Clarisse Palma-Silva INês Cordeiro 《分类学与生物多样性》2013,11(7):658-667
A new species of Euphorbia sect. Brasilienses V.W. Steinm. & Dorsey is described. Euphorbia tetrangularis Hurbath & Cordeiro is endemic to the Serra de Montevidéu, a part of the Espinhaço Range located in the state of Minas Gerais, Brazil. It differs from other species within the section based on the following characters: 4-ribbed branches, green cyathia, and green cyathial glands with erect appendages. This new species would qualify as critically endangered (CR) according to IUCN criteria. An inferred phylogeny based on a combined dataset of nuclear (ITS1) and plastid regions (psbA-trnH, trnC-ycf6, matK, atpI-atpH, psbJ-petA, trnQ-rps16?×?1) confirms the monophyly of Euphorbia sect. Brasilienses and supports the recognition of E. tetrangularis. The phylogeny also suggests that this group probably underwent a recent radiation. 相似文献
4.
5.
The tropical root weevil Diaprepes abbreviatus is a major pest of multiple crops in the Caribbean Islands and has become a serious constraint to citrus production in the United States. Recent work has identified host and conspecific volatiles that mediate host- and mate-finding by D. abbreviatus. The interaction of light, color, and odors has not been studied in this species. The responses of male and female D. abbreviatus to narrow bandwidths of visible light emitted by LEDs offered alone and in combination with olfactory stimuli were studied in a specially-designed multiple choice arena combined with a locomotion compensator. Weevils were more attracted to wavelengths close to green and yellow compared with blue or ultraviolet, but preferred red and darkness over green. Additionally, dim green light was preferred over brighter green. Adult weevils were also attracted to the odor of its citrus host + conspecifics. However, the attractiveness of citrus + conspecific odors disappeared in the presence of a green light. Photic stimulation induced males but not females to increase their speed. In the presence of light emitted by LEDs, turning speed decreased and path straightness increased, indicating that weevils tended to walk less tortuously. Diaprepes abbreviatus showed a hierarchy between chemo- and photo-taxis in the series of experiments presented herein, where the presence of the green light abolished upwind anemotaxis elicited by the pheromone + host plant odor. Insight into the strong responses to visual stimuli of chemically stimulated insects may be provided when the amount of information supplied by vision and olfaction is compared, as the information transmission capacity of compound eyes is estimated to be several orders of magnitude higher compared with the olfactory system. Subordination of olfactory responses by photic stimuli should be considered in the design of strategies aimed at management of such insects. 相似文献
6.
Concepta McManus Júlio Otávio Jardim Barcellos Bruna Krummenauer Formenton Potira Meirelles Hermuche Osmar Abílio de Carvalho Jr RenatoFontes Guimar?es Miguelangelo Gianezini Eduardo Antunes Dias Vinícius do Nascimento Lampert Daniele Zago José Braccini Neto 《PloS one》2016,11(1)
Movement of livestock production within a country or region has implications for genetics, adaptation, well-being, nutrition, and production logistics, particularly in continental-sized countries, such as Brazil. Cattle production in Brazil from 1977 to 2011 was spatialized, and the annual midpoint of production was calculated. Changes in the relative production and acceleration of production were calculated and spatialized using ARCGIS®. Cluster and canonical discriminant analyses were performed to further highlight differences between regions in terms of cattle production. The mean production point has moved from the Center of Minas Gerais State (in the southeast region) to the North of Goiás State (in the Midwest region). This reflects changes in environmental factors, such as pasture type, temperature and humidity. Acceleration in production in the northern region of Brazil has remained strong over the years. More recently, “traditional” cattle-rearing regions, such as the south and southeast, showed a reduction in growth rates as well as a reduction in herd size or internal migration over the period studied. These maps showed that this movement tends to be gradual, with few regions showing high acceleration or deceleration rates. 相似文献
7.
Francisco Severo-Neto Otávio Froehlich 《Marine and Freshwater Behaviour and Physiology》2016,49(1):63-68
Cleaning interactions are known among several groups of fishes, with a higher number of records for marine fish species. These temporary associations occur between one species that acts as the cleaner and the other species as the client. The interaction usually takes place within the boundaries defined by the cleaner. This site, known as the cleaning station, allows the client fish to strike a typical pose allowing the cleaner to approach, such as wide-open fins and inclined, motionless body. Few studies have reported on the cleaning behaviour of freshwater fish species, and none has reported on behaviour that could be interpreted as establishing a cleaning station. Herein we present a new record of the cleaning interaction in the Neotropics, between the cichlid Mesonauta festivus as the cleaner and three species of anostomid (Leporinus macrocephalus, Leporinus friderici and Schizodon borellii) as clients on Pantanal wetlands, as well as the establishment of a defined cleaning station. 相似文献
8.
Rocha DD Dantas IN Albuquerque MR Montenegro RC Pessoa C de Moraes MO Pessoa OD Silveira ER Costa-Lotufo LV 《化学与生物多样性》2007,4(12):2835-2844
A detailed study on the cytotoxic effects of five known constituents isolated from the flowers and roots of Eupatorium betonicaeforme is reported, including 2,2-dimethyl-6-vinylchroman-4-one (1), 2-senecioyl-4-vinylphenol (2), 6-acetyl-2,2-dimethylchroman-4-one (3), (4E)-8beta-angeloyloxy-9beta,10beta-dihydroxy-1-oxogermacra-4,11(13)-dien-12,6alpha-olide (4), and 3beta-hydroxyicosan-1,5beta-olide (5). The sesquiterpene lactone 4 exhibited the highest cytotoxicity, with IC50 values ranging from 3.9 to 9.9 microM, showing some degree of cell selectivity. The antiproliferative activity of 4 was examined towards HL-60 cells, and found to diminish cell viability in a dose-dependent manner. Moreover, at all concentrations tested, there was a decrease in the number of cells capable of incorporating 5-bromo-2'-deoxyuridine (BrdU), indicating disruption of DNA synthesis. The morphological changes induced by 4 were compatible with apoptotic cell death. This work, thus, corroborates the anticancer potential of Eupatorium secondary metabolites. 相似文献
9.
Vincentz M Cara FA Okura VK da Silva FR Pedrosa GL Hemerly AS Capella AN Marins M Ferreira PC França SC Grivet L Vettore AL Kemper EL Burnquist WL Targon ML Siqueira WJ Kuramae EE Marino CL Camargo LE Carrer H Coutinho LL Furlan LR Lemos MV Nunes LR Gomes SL Santelli RV Goldman MH Bacci M Giglioti EA Thiemann OH Silva FH Van Sluys MA Nobrega FG Arruda P Menck CF 《Plant physiology》2004,134(3):951-959
10.
Nóbrega OT Santana JM Sturm NR Teixeira AR Campbell DA 《Memórias do Instituto Oswaldo Cruz》2004,99(5):513-516
This work describes the development and functional testing of two episomes for stable transfection of Trypanosoma cruzi. pHygD contained the 5'- and 3'- flanking regions of the gene encoding the cathepsin B-like protease of T. cruzi as functional trans-splicing and polyadenylation signals for the hygR ORF. Evidence is presented to support extrachromosomal maintenance and organization as tandem repeats in transfected parasites. pPac was derived from pHygD by replacement of the entire hygR ORF with a purR coding region. The ability to modify pHygD and the availability of the complete DNA sequence make these plasmids useful tools for the genetic manipulation of T. cruzi. 相似文献