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81.
Lees CY Briggs DJ Wu X Davis RD Moore SM Gordon C Xiang Z Ertl HC Tang DC Fu ZF 《Veterinary microbiology》2002,85(4):295-303
The objective of this study was to determine if a replication defective recombinant adenovirus expressing rabies virus glycoprotein (Adrab.gp) given through a non-invasive vaccination route (by topical application) onto the skin (NIVS) could elicit an immune response and/or protection against rabies. Groups of mice were immunized by NIVS with various doses of Adrab.gp. For comparison, groups of mice were immunized intramuscularly, subcutaneously, or intradermally with Adrab.gp. Mice received two booster immunizations at 1 and 2 months after the first immunization. Virus neutralizing antibody (VNA) titers were measured at day 21 after the first and second immunizations and at day 14 after the third immunization. Fifty percent of the mice immunized by NIVS with 2 x 10(7) and 2 x 10(8)pfu Adrab.gp vaccine developed VNA, whereas none of the control mice or the mice immunized by NIVS with the lowest dose (2 x 10(6)pfu) of Adrab.gp virus developed VNA. However, this low dose induced high titers of VNA in mice immunized by parenteral routes. Two weeks after the last immunization, all the mice were challenged with a lethal dose of rabies virus. More than 70% of the animals immunized by NIVS with > or = 2 x 10(7)pfu Adrab.gp virus survived the challenge, whereas all the mice in the negative control group and the group immunized by NIVS with the lowest dose of Adrab.gp succumbed to rabies. Taken together, the results suggest that NIVS with Adrab.gp can induce VNA production and protection against lethal challenge with rabies virus in mice. 相似文献
82.
D Aberdein JS Munday KE Dittmer RW Heathcott LA Lyons 《New Zealand veterinary journal》2013,61(6):327-331
Abstract
AIMS
To determine the frequency of the FAS-ligand gene (FASLG) variant associated with feline autoimmune lymphoproliferative syndrome (FALPS) and the proportion of carriers of the variant in three British shorthair (BSH) breeding catteries in New Zealand. 相似文献83.
The combined effect of feed frequency and ration size of diets with and without microbial biomass on the growth and feed conversion of juvenile Penaeus monodon 下载免费PDF全文
Feed management strategies that maximize shrimp growth and optimize feed utilization are critical to the cost‐effectiveness of production. In this study, juvenile Penaeus monodon (~3 g) were cultured for 6 weeks in a laboratory‐based clear‐water tank system. The experiment design was a three‐way factorial with two diets (Diet A – standard industry formulation or Diet B – the same diet with 10% microbial biomass), two feed frequencies (twice or six times daily) and three rations (60%, 80% and 100% of satiation). The results demonstrated clear growth benefits of feeding more than two times per day and feed efficiency benefits of a restricted ration. There was also a significant interaction between frequency and ration, which demonstrated that growth improved using six feeds compared with two feeds as ration amount decreased. The effects of frequency and ration were consistent for both diets; however, the addition of a microbial biomass provided significant growth improvements across all treatments. These outcomes define the gains produced by the combined effect of frequency and ration and suggest a compromise between feed utilization and feeding effort for adoption in feed management strategies. 相似文献
84.
Briggs ( 1960 ) published the first checklist of circumtropical fishes with 107 species. This work served for a half century as the most comprehensive checklist of globally distributed fishes, but the intervening years witnessed many discoveries, and molecular data have changed the way we evaluate species. Here, we update the list guided by taxonomic revisions, phylogenies, phylogeographic data and DNA barcodes. The resulting list now includes 284 species. The dramatic increase is primarily due to two trends: (i) continued oceanic exploration leading to range revisions and species discoveries and (ii) public databases such as FishBase and the Catalogue of Fishes make range data more accessible. Five species were removed from the list as closer scrutiny revealed multiple taxa, 14 were removed due to updated range information, and 35 more are suspected to be species complexes. The species listed here are mostly pelagic and bathypelagic fishes. Euryhaline, anadromous, catadromous, freshwater, and with few exceptions, reef fishes do not achieve global distributions. The most species‐rich family of marine fishes (Gobiidae) is absent. The fishes with the longest pelagic larval stage (Anguillidae) are absent. In contrast, requiem sharks (Carcharhinidae), tunas (Scombridae), jacks (Carangidae), remoras (Echeneidae) and especially lanternfishes (Myctophidae) have multiple representatives. The combined evidence indicates that high mobility as an adult is a key requirement to achieve a global distribution. Many others are members of monotypic genera or families, indicating old lineages that did not diversify. We conclude that global ranges may promote persistence over evolutionary timescales, but also reduce opportunities for speciation. 相似文献
85.
86.
M Briggs M Schmidt D Black R Roach J Opdahl G Stark D Owens M Driver 《Journal of the American Veterinary Medical Association》1988,192(10):1455-1456
An 18-year-old African elephant was determined to have a nonrepairable crack in its left tusk. Treatment included extraction of the tusk, using rotational and extractional forces, and administration of antibiotics, followed by 1 year of flushing the opened tusk cavity with warm tap water. Two years after surgery, the elephant was healthy, and the tusk cavity was 80% filled with normal tissue. 相似文献
87.
88.
Estimating the mass of asteroid 253 mathilde from tracking data during the NEAR flyby 总被引:1,自引:0,他引:1
DK Yeomans J Barriot DW Dunham RW Farquhar JD Giorgini CE Helfrich AS Konopliv JV McAdams JK Miller WM Owen DJ Scheeres SP Synnott BG Williams 《Science (New York, N.Y.)》1997,278(5346):2106-2109
The terminal navigation of the Near Earth Asteroid Rendezvous (NEAR) spacecraft during its close flyby of asteroid 253 Mathilde involved coordinated efforts to determine the heliocentric orbits of the spacecraft and Mathilde and then to determine the relative trajectory of the spacecraft with respect to Mathilde. The gravitational perturbation of Mathilde on the passing spacecraft was apparent in the spacecraft tracking data. As a result of the accurate targeting achieved, these data could be used to determine Mathilde's mass as 1.033 (+/- 0.044) x 10(20) grams. Coupled with a volume estimate provided by the NEAR imaging team, this mass suggests a low bulk density for Mathilde of 1.3 grams per cubic centimeter. 相似文献
89.
This study assessed the cultural and weed management factors influencing the weed communities of Hungarian rice fields. Hungary is situated at the northern limit of rice production with a history of about 300 years of rice culture. We surveyed the weed flora and 25 background variables in 100 active rice fields. Using a minimal adequate model containing 11 terms, 48.5% of the total variation in weed species data could be explained. The net effects of nine variables on species composition were significant. Crop cover was found to be the most important explanatory variable, which was followed by the herbicides penoxsulam and azimsulfuron, tillage depth, phosphorous and potassium fertilisers, years after last rotation, water depth in May, sowing type, pendimethalin and water conductivity. Filamentous algae, as the most abundant group of weeds, were positively associated with deep tillage, deep water and surface sowing. Echinochloa crus‐galli, one of the most troublesome grass weeds, was associated with low rice cover, shallow water and later years after crop rotation, while weedy rice favoured high crop cover, deep water and soil sowing. These findings can be used to design improved weed management strategies. The occurrence of red list species and charophytes in diverse micro‐mosaic patterns deserves attention from a conservation perspective, as well. The maintenance of these unique charophyte communities can be facilitated by shallow tillage without soil inversion. 相似文献
90.