Serological screening of farm dogs for Echinococcus granulosus infection in an endemic region     

RB GASSER  MW LIGHTOWLERS  MD RICKARD  RA LYFORD  HJS DAWKINS† 《Australian veterinary journal》1990,67(4):145-147

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Three-dimensional structure of interleukin-2   总被引：17，自引：0，他引：17  

B J Brandhuber  T Boone  W C Kenney  D B McKay 《Science (New York, N.Y.)》1987,238(4834):1707-1709

Interleukin-2 is an effector protein that participates in modulating the immune response; it has become a focal point for the study of lymphokine structure and function. The three-dimensional structure of the interleukin molecule has been solved to 3.0 angstrom resolution. Interleukin-2 has a novel alpha-helical tertiary structure that suggests one portion of the molecule forms a structural scaffold, which underlies the receptor binding facets of the molecule.  相似文献   

Forest biogeochemistry and primary production altered by nitrogen saturation   总被引：1，自引：0，他引：1  

John D. Aber  Alison Magill  Steven G. Mcnulty  Richard D. Boone  Knute J. Nadelhoffer  Marty Downs  Richard Hallett 《Water, air, and soil pollution》1995,85(3):1665-1670

Results from four intensive site-level manipulations and one extensive field survey in northern temperate and boreal forests show a consistent set of responses to chronic N additions. These include 1) initial and often large increase in net N mineralization followed by decreases, 2) increases in net nitrification. 3) increases in N concentration in foliage, and 4) decreased Mg∶N and Ca∶Al ratios, and declining tree growth and vigor in all evergreen stands. These results are synthesized into a set of proposed summary relationships that define the temporal pattern of responses of N-limited systems to N additions.  相似文献   

Contagious ecthyma in the live sheep export industry     

ARB HIGGS  RT NORRIS  FC BALDOCK  NJ CAMPBELL  S. KOH  RB RICHARDS 《Australian veterinary journal》1996,74(3):215-220

Objective: To investigate control options for contagious ecthyma (scabby mouth) in Australian sheep exported live to the Middle East.
Design: Prevalence, vaccination and modelling studies.
Procedure: One hundred and forty weaner sheep (less than 1 year old) on each of 106 farms in Western Australia (WA) and 18 farm groups of adult wethers received at a WA commercial feedlot were examined for lesions of scabby mouth. Sheep on a total of 26 farms in 3 States were divided into treatment and control groups for the vaccination study. A simple deterministic compartmental model was developed to establish which parameters had the greater effect on disease prevalence.
Results: The proportion of farms with evidence of scabby mouth in weaner sheep was 23.6% and, on those farms with the disease, the overall prevalence was 6.1%. At the feedlot, 4 out of 18 farm groups had 5 or more sheep with lesions on arrival. The overall prevalence in the 4 diseased groups was 5.2%. Sheep vaccinated on farm before trucking to the feed-lot had a lower prevalence of scabby mouth at the end of simulated shipping than controls. The main determinant of scabby mouth prevalence was the proportion of sheep immune to the disease.
Conclusion: A program of vaccination for scabby mouth will reduce the prevalence of disease during live export. However, using current technology it is not possible to deliver shipments of sheep to the Middle East that are guaranteed completely free of scabby mouth.  相似文献   

The interactive effects of UV-B and insecticide exposure on tadpole survival, growth and development     

Christine M. Bridges  Michelle D. Boone 《Biological conservation》2003,113(1):49-54

Because declines within amphibian populations can seldom be attributed to a single cause, it is important to focus on multiple stressors, both natural and anthropogenic. Variables such as UV-B radiation and chemical contamination can interact with one another in ways that might not be predicted from single-factor studies. We exposed southern leopard frog (Rana sphenocephala) tadpoles to the insecticide carbaryl and varying intensities of UV-B radiation in artificial ponds and examined their effects on survival, size at metamorphosis, and the duration of the larval period. Tadpole survival to metamorphosis was positively influenced by UV-B intensity. Tadpoles in ponds exposed to carbaryl contained over three times more algae and yielded larger metamorphs than control ponds. Although previous laboratory studies have indicated carbaryl becomes more toxic in the presence of UV-B, we did not find such an effect, perhaps because of the protection afforded by dissolved organic carbon within the ponds. Our research emphasizes the importance of conducting field studies to more accurately predict what occurs under a natural setting.  相似文献   

Suspected jute seed (Corchorus olitorius) poisoning of cattle     

RA McKENZIE  RB CALLINAN  DB UNGER  MA FLANAGAN 《Australian veterinary journal》1992,69(5):117-118

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Molecular characterization of a stable antisense chalcone synthase phenotype in strawberry (Fragaria x ananassa)     

Lunkenbein S  Coiner H  de Vos CH  Schaart JG  Boone MJ  Krens FA  Schwab W  Salentijn EM 《Journal of agricultural and food chemistry》2006,54(6):2145-2153

An octaploid (Fragaria x ananassa cv. Calypso) genotype of strawberry was transformed with an antisense chalcone synthase (CHS) gene construct using a ripening related CHS cDNA from Fragaria x ananassa cv. Elsanta under the control of the constitutive CaMV 35S promoter via Agrobacterium tumefaciens. Out of 25 transgenic lines, nine lines showed a reduction in CHS mRNA accumulation of more than 50% as compared to the untransformed cv. Calypso control. The antisense CHS construct was found to be integrated into the genome, with a copy number ranging from one to four. The pigmentation of the fruit was only affected when less than 5% of the control CHS expression level was detected. A stable antisense phenotype over a period of 4 years was obtained in the primary transgenic lines at a rate of 1:20. As a consequence of the reduced activity of CHS, the levels of anthocyanins, flavonols, and proanthocyanidins were downregulated and precursors of the flavonoid pathway were shunted to the phenylpropanoid pathway leading to highly increased levels of cinnamoyl glucose (520% of control), caffeoyl glucose (816% of control), and feruloyl glucose (1092% of control) as well as p-coumaryl alcohol (363% of control) and p-coumaryl-1-acetate (1079% of control), which occur only as trace components in untransformed control fruits. These results demonstrate that the introduction of an antisense CHS construct in strawberry results in an unpredictable biochemical phenotype, thereby confirming that CHS function is an important regulatory point of substrate flow between the flavonoid and the phenylpropanoid pathways.  相似文献   

Dynamics of microcrack propagation in hardwood during heat treatment investigated by synchrotron-based X-ray tomographic microscopy     

Marjan Sedighi Gilani  Julie L. Fife  Matthieu N. Boone  Karim Ghazi Wakili 《Wood Science and Technology》2013,47(5):889-896

The process of crack propagation in wood during pyrolysis is strongly linked to heterogeneities in its hierarchical porous structure. Fundamental understanding of this process is necessary for the analysis of the behavior of wood structural elements during fire exposure. Synchrotron-based X-ray tomographic microscopy combined with a recently developed laser-based furnace at the TOMCAT beamline of the Swiss Light Source provides a unique opportunity to study the heat-induced propagation of microcracks in hardwood in situ with high spatial and temporal resolutions. In this study, attention was focused on the 3D microstructure of beech and the interconnectivity between morphology and cracking patterns. It is shown that thermal cracks initiate mainly along the ray cells in hardwood and in the junction of seasonal growth layers. There is a clear indication of increased total porosity of the wood due to charring.  相似文献   

Distribution and risk factors of bovine cysticercosis in Belgian dairy and mixed herds   总被引：1，自引：1，他引：0  

Boone I  Thys E  Marcotty T  de Borchgrave J  Ducheyne E  Dorny P 《Preventive veterinary medicine》2007,82(1-2):1-11

Bovine cysticercosis is an important food safety issue that is of economic concern. In Belgium, in the last years an increase in the number of cases, mostly light infections, was observed. The role of contact with contaminated surface water has been hypothesized as the main route of transmission. Based on abattoir records from 2001 till 2003 the distribution and risk factors of bovine cysticercosis among dairy and mixed farms were studied in four provinces, using Geographic Information Systems (GIS) and questionnaires. The risk factors were analysed using a case-control study design. The case group consisted of herds from which homebred cattle with cysticercosis had been detected at the abattoir; the control group was composed of herds where no cases had been detected. Case herds were distributed over the study area. A logistic regression analysis revealed that the location (province), the number of slaughtered cattle, the flooding of pastures, free access of cattle to surface water and the proximity of wastewater effluent were significant explanatory variables for bovine cysticercosis to be recorded in a herd.  相似文献   

Corticosteroid intralesional injection of subchondral bone cysts     

L. Helms Boone  J. Peroni 《Equine Veterinary Education》2009,21(12):638-639

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