排序方式: 共有88条查询结果,搜索用时 156 毫秒
81.
82.
Tzu-Yin Lin Rachael Thomas Pei-Chien Tsai Matthew Breen Cheryl A. London 《Veterinary immunology and immunopathology》2009,127(1-2):114-124
Studies using the currently available malignant canine mast cell lines and bone marrow-derived cultured mast cells (BMCMCs) have provided an in-depth understanding of normal and neoplastic canine mast cell biology. However, many of the currently available malignant canine mast cell lines possess limitations, including loss of cell surface markers and inability to bind canine IgE. We have recently generated a novel mast cell line, CL1, from an 11-year-old spayed female Labrador retriever diagnosed with systemic mastocytosis and neoplastic effusion. The CL1 cells express KIT, Fc?RI, CD44, CD45, CD14, CD11a, CD11b and CD18 as well as chymase. Interestingly, these cells express wild-type KIT, with no evidence of autophosphorylation, but are able to proliferate independently without the addition of exogenous stem cell factor (SCF), KIT ligand. However, stimulation of CL1 cells with SCF induces KIT phosphorylation promoting cell proliferation. The CL1 cells retain functional properties of mast cells, degranulating in a dose-dependent manner in response to both IgE cross-linking and chemical stimulation. Lastly, cytogenetic evaluation revealed several recurrent tumor-associated chromosome copy number imbalances in the CL1 line. In summary, the CL1 cell line possesses phenotypic and functional properties similar to those found in canine BMCMCs, and will likely be a useful tool to study mast cell biology, factors regulating transformation of mast cells, cytogenetic abnormalities in mast cell tumors, and novel preclinical therapies. 相似文献
83.
Impact of sludge residence time on the relative biodegradation and biosorption of sulfonamide antibiotics in activated sludge 总被引:1,自引:0,他引:1
YANG Cheng GUO Jin song Belinda S.M. Sturm Rachael F. Lane Craig D. Adams Ray E. Carter 《保鲜与加工》2012,(6):63-71
Four sequencing batch reactors (SBR) are operated with sludge residence time (SRT)of 2, 8, 14, and 20 days to analyze the impact of SRT on removal of sulfanomide (5 μg/L). In batch experiments, three treatments (active biomass, inhibited biomass, and controls of no biomass) are performed in 100 mL batch reactors in triplicate that simulated one SBR cycle, and are investigated to distinguish biodegradation, biosorption, and volatilization losses, respectively. The results show that biomass removed an average 2.14±0.60 μg/g SS of sulfamethoxazole, 1.14±0.63 μg/g SS of sulfadiazine, 2.33±0.67 μg/g SS of sulfadimethoxine, 2.45±0.85 μg/gSS of sulfamerazine, with 63%, 83%, 35%, 55% of the removal respectively due to sorption. When SBRs (3 L total volume) are spiked continuously with 5 μg/L sulfamethoxazole for 60 days, 10%, 41%, 51%, 58% is removed with SRTs of 2d, 8d, 14d, 20d, respectively. Removal increased significantly with SRT, but the normalized mass removed per gram of biomass decreases. Growth of filamentous organisms with a 2-d SRT increases the sorption capacity of this sludge, although biodegradation is the dominant mechanism for removal. Higher biomass concentrations established by longer SRTs are more significant for biodegradation than species diversity, which do not vary with SRT. As wastewater treatment plants implement longer SRTs for nutrient removal, they will also achieve improved removal of some pharmaceuticals. 相似文献
84.
85.
Background
Understanding the dispersal and genetic structure of invasive insects across islands is important for designing management plans that are appropriate at spatial and temporal scales. For invasive parasites, population dynamics are largely determined by the distribution and density of their host species. The introduced parasitic fly, Philornis downsi, parasitises nestlings of endemic birds on all major islands of the Galápagos archipelago. The fly's high mortality and fitness impacts are of conservation concern for vulnerable and declining species of Darwin's finches. Using microsatellite data in Bayesian clustering and landscape genetic analyses, we examine gene flow and dispersal in P. downsi between three islands and across habitats (highlands, lowlands) and examine for the presence of population bottlenecks. We also examine variation at the mitochondrial gene CO1 across islands to establish if cryptic species were present. 相似文献86.
Rachael W. Quinn Amy O. Burk Thomas G. Hartsock Erin D. Petersen Niki C. Whitley Kibby H. Treiber Raymond C. Boston 《Journal of Equine Veterinary Science》2008
The effects of dietary energy source, controlled weight gain, and exercise restriction on insulin sensitivity (SI) were studied in mature Thoroughbred geldings with body condition scores (BCS) of 4.3 ± 0.1. Two dietary energy sources were used, one high in starch and sugar (HS; n = 9) and one high in fat and fiber (HF; n = 7), and horses were fed 20 Mcal digestible energy (DE)/day above maintenance requirements to encourage weight gain. Using the minimal model of glucose and insulin dynamics, no differences in SI between groups were noted before initiation of treatment concentrate feeding. After dietary acclimation, SI was decreased in HS (P < 0.01) as compared with HF. After 32 weeks of controlled weight gain (90.8 kg; final BCS, 7.0 ± 0.1), SI remained lower in HS (P = 0.07) but did not change from the preweight gain value. SI in HF did not change between the start and end of weight gain. After completion of weight gain, exercise was restricted for 2 weeks, resulting in a reduction in SI in HF (P = 0.03) but no change in HS. It was concluded that dietary energy source may be more influential than weight gain on SI in the mature Thoroughbred gelding between BCS 4 and 7. The higher SI found in horses consuming the HF diet appeared to be partially dependent on some level of physical activity. 相似文献
87.
David R. Thompson Kimberly T. Goetz Paul M. Sagar Leigh G. Torres Caitlin E. Kroeger Lisa A. Sztukowski Rachael A. Orben Andrew J. Hoskins Richard A. Phillips 《水产资源保护:海洋与淡水生态系统》2021,31(10):2967-2978
- The use of miniaturized electronic tracking devices has illuminated our understanding of seabird distributions and habitat use, and how anthropogenic threats interact with seabirds in both space and time. To determine the year-round distribution of adult Campbell albatross (Thalassarche impavida), a single-island endemic, breeding only at Campbell Island in New Zealand's subantarctic, a total of 68 year-long location data sets were acquired from light-based geolocation data-logging tags deployed on breeding birds in 2009 and 2010.
- During the incubation and chick-guard phases of the breeding season, birds used cool (<10°C) waters over the Campbell Plateau, but also ranged over deeper, shelf-break and oceanic waters (4,000–5,500 m) beyond the Plateau. Later in the breeding season, during post-guard chick-rearing, Campbell albatrosses exploited generally deep waters (4,000–5,000 m) beyond the Campbell Plateau.
- During the non-breeding period, adults tended to move northwards into warmer (approximately 15°C) waters and occupied areas beyond western Australia in the west to offshore from Chile in the east. Overall, about 30% of adults spent some of their non-breeding period in the central and eastern Pacific Ocean, substantially expanding the previously reported range for this species.
- One bird, that failed in its breeding attempt in October 2009, departed Campbell Island and circumnavigated the southern oceans before being recaptured back at Campbell Island in October 2010. This is the first example of an annually-breeding albatross species completing a circumnavigation between breeding attempts.
- Overlap with fishing effort, using data from the Global Fishing Watch database, was assessed on a monthly and seasonal basis. Generally, levels of overlap between Campbell albatross and fishing effort were relatively low during the breeding season but were approximately 60% higher during the non-breeding period, underlining the need for international initiatives to safeguard this species.
88.