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991.
Colville EJ Carlson AE Beard BL Hatfield RG Stoner JS Reyes AV Ullman DJ 《Science (New York, N.Y.)》2011,333(6042):620-623
To ascertain the response of the southern Greenland Ice Sheet (GIS) to a boreal summer climate warmer than at present, we explored whether southern Greenland was deglaciated during the Last Interglacial (LIG), using the Sr-Nd-Pb isotope ratios of silt-sized sediment discharged from southern Greenland. Our isotope data indicate that no single southern Greenland geologic terrane was completely deglaciated during the LIG, similar to the Holocene. Differences in sediment sources during the LIG relative to the early Holocene denote, however, greater southern GIS retreat during the LIG. These results allow the evaluation of a suite of GIS models and are consistent with a GIS contribution of 1.6 to 2.2 meters to the ≥4-meter LIG sea-level highstand, requiring a significant sea-level contribution from the Antarctic Ice Sheet. 相似文献
992.
de la Fuente R Ballesteros C Bautista V Medina A Orden JA Domínguez-Bernal G Vindel A 《Veterinary microbiology》2011,150(1-2):198-202
Staphylococcus aureus subsp. anaerobius, a microaerophilic, catalase-negative bacteria, is the etiological agent of abscess disease, a specific chronic condition of sheep and goats, characterized by the formation of necrotic lesions that are typically located in superficial lymph nodes. In this study, molecular analysis including pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST) and accessory gene regulator (agr) typing was carried out on 94 S. aureus subsp. anaerobius strains isolated in different countries (79 were isolated from 35 outbreaks of the disease in Spain from 1981 to 2009, 9 were isolated in Italy, 3 in Denmark and 3 in Sudan). All of the 94 S. aureus subsp. anaerobius isolates examined belonged to one PFGE type, within which four minority subtypes were identified. Representative isolates of all PFGE subtypes as well of all countries belonged to the same sequence type (ST), ST1464, which was a singleton, and to the agr type II. Our results support the view that abscess disease is caused by a single bacterial clone worldwide. This bacterium has existed for at least a century and, thus, has undergone long-term small ruminant host restriction. 相似文献
993.
The pentastome species, Porocephalus clavatus, has been found to infect the lungs of two species of snakes in the family Boidae family (Boa constrictor and Epicrates cenchria). The individual of B. constrictor was collected in the Amazonian rainforest of Departamento Loreto, Peru. The E. cenchria was recovered from the pet trade in Lima, Peru's capital city. A total of 22 P. clavatus were collected and examined from these two snakes. This is the first report of P. clavatus in Peru. The morphology of the parasites and the possible importance in public and animal health are discussed. 相似文献
994.
Pourrut X Diffo JL Somo RM Bilong Bilong CF Delaporte E LeBreton M Gonzalez JP 《Veterinary parasitology》2011,175(1-2):187-191
To document the prevalence of gastrointestinal parasites in Cameroonian monkeys and to assess the risk of transmission to humans, we sampled 125 primates belonging to 15 species, of which 78 had been captured for bushmeat in the wild, and 47 were pets kept in urban areas. Seven nematode species, one trematode, one cestode and three protozoa were detected. Eight different parasite species were found in Cercopithecus nictitans and six in C. neglectus, C. pogonias and Cercocebus agilis. Helminths were found in 77% of monkeys, and protozoa in 36%. Trichuris sp. and Entamoeba coli were the most frequent parasites, being found in 54% and 36% of animals, respectively. Helminths were more frequent in adults than in juveniles, while the prevalence of protozoa was not age-related. No significant gender difference was found. Bushmeat monkeys had a significantly higher prevalence of helminth infection than pets (92% versus 51%), whereas there was no significant difference in the prevalence of protozoa (32% versus 43%). Among helminth species, Strongyloides fulleborni was more prevalent in bushmeat monkeys than in pets (55% versus 15%), as were Ancylostoma spp. (62% versus 9%). As these parasites are transmitted transcutaneously by infectious larva, they have a high potential for transmission to humans, during butchering. One pet monkey kept in an urban household in Yaoundé was infected by Schistosoma mansoni. The potential public health implications of these findings are discussed. 相似文献
995.
Li J Gonzalez JM Walker DK Hersom MJ Ealy AD Johnson SE 《Journal of animal science》2011,89(6):1751-1757
Satellite cells are a heterogeneous population of myogenic precursors responsible for muscle growth and repair in mammals. The objectives of the experiment were to examine the growth rates and degree of heterogeneity within bovine satellite cells (BSC) isolated from young and adult animals. The BSC were harvested from the semimembranosus of young (4.3 ± 0.5 d) and adult (estimated 24 to 27 mo) cattle and cultured en masse. Young animal BSC re-enter the cell cycle sooner and reach maximal 5-ethynyl-2'-deoxyuridine (EdU) incorporation earlier (P < 0.05) than adult contemporaries. Adult BSC contain fewer (P < 0.05) MyoD and myogenin immunopositive nuclei than BSC isolated from young animals after 3, 4, and 5 d in culture. These results indicate that BSC from young animals activate, proliferate, and differentiate sooner than isolates from adult animals. Lineage heterogeneity within BSC was examined using antibodies specific for Pax7 and Myf5, lineage markers of satellite cells, and myoblasts. Immunocytochemistry revealed the majority of Pax7-expressing BSC also express Myf5; a minor population (~5%) fails to exhibit Myf5 immunoreactivity. The percentage of Pax7:Myf5 BSC from young animals decreases sooner (P < 0.05) in culture than adult BSC, indicating a more rapid rate of muscle fiber formation. A subpopulation immunopositive for Myf5 only was identified in both ages of BSC isolates. The growth kinetics and heterogeneity of young BSC was further evaluated by clonal analysis. Single cell clones were established and analyzed after 10 d. Colonies segregated into 2 groups based upon population doubling time. Immunostaining of the slow-growing colonies (population doubling time ≥ 3 d) revealed that a portion exhibited asymmetric distribution of the lineage markers Pax7 and Myf5, similar to self-renewable mouse muscle stem cells. In summary, these results offer insight into the heterogeneity of BSC and provide evidence for subtle differences between rodent and bovine myogenic precursors. 相似文献
996.
A lactic-acid producing bacterium was isolated from the rumen of lambs with rumen acidosis. The cells were Gram-positive, nonmotile, nonsporing, catalase negative spherical, 1.5-2.0 μm in diameter, and occur in pairs and tetrads. Analysis of 16S ribosomal RNA indicated that the rumen bacterium was a strain of Pediococcus acidilactici with 99% of nucleotide homology. This bacterium was sensible to monensin and lasalocid at the unique dose tested of 300 ppm. The concentration of lactic acid and DM degradation decreased (P < 0.05) when monensin or lasalocid were added to the culture media after 24, 48 and 72 h of incubation. In contrast, total VFA concentration and pH were higher (P < 0.05) in the culture media added with the ionophores. Up to now S. bovis is considered the main ruminal bacterium related with rumen acidosis, but the importance of P. acidilactici should be also reconsidered in experimental studies focused on the control rumen acidosis. 相似文献
997.
998.
Bertazzon Nadia Migliaro Daniele Rossa Alberto Filippin Luisa Casarin Sofia Giust Mirella Brancadoro Lucio Crespan Manna Angelini Elisa 《植物病害和植物保护杂志》2021,128(4):1115-1119
Journal of Plant Diseases and Protection - Limited information is available on the distribution of grapevine red blotch virus (GRBV) in grape-growing regions outside North America. In this study,... 相似文献
999.
Magaña-Álvarez Anuar Ahmed Pérez-Brito Daisy Vargas-Hernández Brenda Yazmín Ramírez-Pool José Abrahán Núñez-Muñoz Leandro Alberto Salgado-Ortiz Héctor de la Torre-Almaraz Rodolfo Medrano Roberto Ruiz- Xoconostle-Cázares Beatriz 《植物病害和植物保护杂志》2021,128(6):1627-1635
Journal of Plant Diseases and Protection - Tomato brown rugose fruit virus (ToBRFV) is a novel tobamovirus initially reported in Jordan and Israel, and, more recently, in Europe, China, the USA and... 相似文献
1000.
Jonas Alberto Rios Daniel Debona Henrique Silva Silveira Duarte Fabrício Avila Rodrigues 《European journal of plant pathology / European Foundation for Plant Pathology》2013,136(3):603-611
This study aimed to develop and validate a standard area diagram set (SADS) to quantify the severity of blast, caused by Pyricularia oryzae, on wheat leaves. The SADs has ten levels: 0.1, 1, 5, 10, 22, 32, 42, 52, 62 and 72 % blast severity. To validate the SADs, 12 inexperienced raters estimated disease severity on 50 images of leaves from cultivars BR-18 (susceptible) and BRS-229 (partially resistant). Blast severity was first estimated without the use of the SADs on 50 leaves with a range of blast severity. The same raters evaluated the same 50 leaves using the SADs as an aid. The SADs improved accuracy (coefficient of bias, C b ?=?0.88 and 0.99, without and with SADs, respectively) and agreement (Lin’s concordance correlation coefficient, ρ c ?=?0.84 and 0.96 without and with SADs, respectively) of the estimates of severity. The absolute error was (-) 52 % without the SADs and (-) 24 % when using SADs as an aid. Severity estimates were more reliable when using SADs (R2?=?0.87 unaided and R2?=?0.92 with SAD). The SADs proposed in this study will improve accuracy and reliability of estimates of blast severity on wheat leaves. 相似文献