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91.
92.
Tyre E Eisenbart D Foley P Burton S 《The Canadian veterinary journal. La revue veterinaire canadienne》2007,48(7):734-736
A young dog was presented with a history of chronic diarrhea, anorexia, and weight loss. Histoplasma capsulatum was suspected, based on cytologic examination of lymph node aspirates and peritoneal fluid, and confirmed by fungal culture. To our knowledge, this is the first case of histoplasmosis diagnosed in a dog in Atlantic Canada. 相似文献
93.
The pathogenesis of 4 isolates of turkey-origin reovirus (NC/SEP-R44/03, NC/98, TX/98, and NC/85) and 1 chicken-origin reovirus (1733) was examined by infecting specific pathogen free (SPF) poults. These turkey-origin reovirus (TRV) isolates were collected from turkey flocks experiencing poult enteritis and are genetically distinct from previously reported avian reoviruses. Microscopic examination of the tissues collected from the TRV-infected poults revealed different degrees of bursal atrophy characterized by lymphoid depletion and increased fibroplasia between the bursal follicles. To understand the relationship between virus spread and replication, and the induction of lesions, immunohistochemical staining (IHC) for viral antigen, in situ hybridization (ISH) for the detection of viral RNA, and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay for the detection of apoptosis in affected tissues was performed. Both IHC and ISH revealed viral antigen and RNA in the surface epithelial cells of the bursa, in macrophages in the interstitium of the bursa and, to lesser degree, in splenic red pulp macrophages and intestinal epithelial cells. Increased apoptosis of bursal lymphocytes and macrophages was observed at 2 and 5 days postinoculation. No lesions were found in tissues from poults inoculated with the virulent chicken-origin strain, however viral antigen was detected in the bursa and the intestine. Although all TRVs studied displayed similar tissue tropism, there were substantial differences in the severity of the lesions produced. Poults inoculated with NC/SEP-R44/03 or NC/98 had moderate to severe bursal atrophy, whereas poults inoculated with TX/98 or NC/85 presented a mild to moderate bursal lymphoid depletion. The lymphoid depletion observed in the bursa appears to be the effect of an indirectly induced apoptosis and would most likely result in immune dysfunction in poults infected with TRV. 相似文献
94.
Luisa NERI Fabiano SILLO Elisa ZAMPIERI Erica LUMINI Giovanni MARTURANO Chiara Degli ESPOSTI Gianniantonio PETRUZZELLI Beniamino GIOLI Alessandro ZALDEI Rita BARALDI Raffaella BALESTRINI 《土壤圈》2023,33(4):670-675
<正>Dear Editor,Soil quality is defined as“the capacity of a soil to function,within ecosystem and land use boundaries,to sustain productivity,maintain environmental quality,and promote plant and animal health”(Doran and Parkin 1994).In this context,soil functionality is fundamental to the biosphere and is highly dependent on the associated microbiota.Soil microorganisms are relevant for terrestrial ecosystem functioning,and understanding the functional changes of the biological community i... 相似文献
95.
Background
Herbivory can affect every aspect of a plant's life. Damaged individuals may show decreased survivorship and reproductive output. Additionally, specific plant species (legumes) and tissues (flowers) are often selectively targeted by herbivores, like deer. These types of herbivory influence a plant's growth and abundance. The objective of this study was to identify the effects of leaf and meristem removal (simulated herbivory within an exclosure) on fruit and flower production in four species (Rhus glabra, Rosa arkansana, Lathyrus venosus, and Phlox pilosa) which are known targets of deer herbivory. 相似文献96.
Roberto Borriello Erica Lumini Mariangela Girlanda Paola Bonfante Valeria Bianciotto 《Biology and Fertility of Soils》2012,48(8):911-922
As obligate mutualistic symbionts, arbuscular mycorrhizal fungi (AMF) colonize the roots of many agricultural crops, and it is often claimed that agricultural practices are detrimental to AMF. As a result, agroecosystems impoverished in AMF may not get the fully expected range of benefits from these fungi. Using molecular markers on DNA extracted directly from soil and roots, we studied the effects of different management practices (tillage and N fertilization) on the AMF communities colonizing an experimental maize field in Central Italy. Our molecular analysis based on three different nuclear rRNA regions (18S, 28S and ITS) allowed us to assess AMF biodiversity. Glomeraceae members were the main colonizer, and they co-occurred with Gigasporaceae and Paraglomus regardless of the management practices applied. Diversisporaceae and Entrophosporaceae members were instead detected in the N-fertilized soils and in the untreated soil, respectively. The results obtained indicated that the general AMF assemblages structure and composition in the maize field plots appear to be primarily influenced by N fertilization and, to a lesser extent, by tillage. This study also validates the usefulness of multiple molecular markers to consolidate and refine the assessment of the environmental AMF diversity. 相似文献
97.
98.
The genome of the sea urchin Strongylocentrotus purpuratus 总被引:2,自引:0,他引:2
Sea Urchin Genome Sequencing Consortium Sodergren E Weinstock GM Davidson EH Cameron RA Gibbs RA Angerer RC Angerer LM Arnone MI Burgess DR Burke RD Coffman JA Dean M Elphick MR Ettensohn CA Foltz KR Hamdoun A Hynes RO Klein WH Marzluff W McClay DR Morris RL Mushegian A Rast JP Smith LC Thorndyke MC Vacquier VD Wessel GM Wray G Zhang L Elsik CG Ermolaeva O Hlavina W Hofmann G Kitts P Landrum MJ Mackey AJ Maglott D Panopoulou G Poustka AJ Pruitt K Sapojnikov V Song X Souvorov A Solovyev V Wei Z 《Science (New York, N.Y.)》2006,314(5801):941-952
We report the sequence and analysis of the 814-megabase genome of the sea urchin Strongylocentrotus purpuratus, a model for developmental and systems biology. The sequencing strategy combined whole-genome shotgun and bacterial artificial chromosome (BAC) sequences. This use of BAC clones, aided by a pooling strategy, overcame difficulties associated with high heterozygosity of the genome. The genome encodes about 23,300 genes, including many previously thought to be vertebrate innovations or known only outside the deuterostomes. This echinoderm genome provides an evolutionary outgroup for the chordates and yields insights into the evolution of deuterostomes. 相似文献
99.