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131.
132.
In 1985, members of the veterinary profession and four other professional groups in New Zealand were surveyed to establish their attitudes towards the developing commercialisation of their professions, and particularly towards advertising. This survey was repeated in 1988, and again in 1994. The results of the three surveys are presented in this paper. There was a sharp movement towards acceptance of advertising, and toward a competitive orientation in general, between 1985 and 1988, with a consolidation of these changes during the following 6 years. The acceptance of the idea of an openly competitive profession now has widespread support among veterinarians. Similarly, there is general support for the use of most kinds of informative advertising, with many practitioners viewing advertising as a business building tool, but with the advertising of fees remaining an area over which there is still considerable caution. Although clients are seen as more demanding than in the past, the client-practitioner relationship is still expected to be an enduring one. We suggest that, in view of the relaxed attitudes towards advertising that now exists among members of the veterinary profession, control of advertising should cease to be a concern to the profession.  相似文献   
133.
OBJECTIVE: To compare the precision of tibial plateau leveling osteotomy (TPLO) surgery when performed with or without a jig. STUDY DESIGN: Cadaveric study. SAMPLE POPULATION: Cadaveric, adult greyhound hindlimbs (n=9 pair). METHODS: TPLO (n=18) was performed on each limb pair; 1 with and 1 without use of a jig. Measurements taken from pre- and postsurgical radiographs were osteotomy position, tibial plateau angle (TPA), varus-valgus malalignment, and tibial torsion. The null hypothesis was that TPLO precision was not affected by use of a jig. Student's t-test was used to investigate differences in TPA, osteotomy location, and frequency and extent of iatrogenic limb malalignment; P<.05 was considered significant. RESULTS: There were no significant differences in postsurgical TPA, tibial crest thickness, varus-valgus malalignment, or tibial torsion between TPLOs performed with or without a jig. Osteotomy location was significantly more distal when a jig was used (P=.03). CONCLUSIONS: Jig use did not improve the precision of TPLO surgery. CLINICAL RELEVANCE: Performing TPLO without a jig should reduce surgery time, eliminate complications related to placement of the distal jig pin and allow unhindered positioning of the osteotomy.  相似文献   
134.
The anionic ruthenium cluster carbonylates [Ru6C(CO)16]2- or [H2Ru10(CO)25]2- interspersed with bis(triphenylphosphino)iminium counterions (PPN+) are incorporated from solution into the pores of MCM-41 mesoporous silica (3 nanometers in diameter), where they form tightly packed arrays. These arrays were shown by high-resolution transmission electron microscopy, Fourier transform optical diffraction, and computer simulations to be well ordered both along and perpendicular to the axis of the cylindrical pores. In their denuded state produced by gentle thermolysis, the cluster carbonylates yield nanoparticles of ruthenium that are less well ordered than their assimilated precursors but show good activity as hydrogenation catalysts for hexene and cyclooctene. In both their as-prepared and denuded states, these encapsulated clusters are likely to exhibit interesting electronic and other properties.  相似文献   
135.
Aluminas and their surface chemistry play a vital role in many areas of modern technology. The behavior of adsorbed water is particularly important and poorly understood. Simulations of hydrated alpha-alumina (0001) surfaces with ab initio molecular dynamics elucidate many aspects of this problem, especially the complex dynamics of water dissociation and related surface reactions. At low water coverage, free energy profiles established that molecularly adsorbed water is metastable and dissociates readily, even in the absence of defects, by a kinetically preferred pathway. Observations at higher water coverage revealed rapid dissociation and unanticipated collective effects, including water-catalyzed dissociation and proton transfer reactions between adsorbed water and hydroxide. The results provide a consistent interpretation of the measured coverage dependence of water heats of adsorption, hydroxyl vibrational spectra, and other experiments.  相似文献   
136.
Although 36 DLA-DRB1 and 10 DLA-DQA1 allele sequences have been published to date, no data on individual allele frequencies exists, either for specific breeds or cross breeds, and the full extent of the polymorphism at each of these loci is still not known. We have used sequence-specific oligonucleotide probing (SSOP) to characterise a series of 367 dogs for their DRB1 and DQA1 alleles. These included individual animals from over 60 different breeds, with numbers per breed ranging from 1 to 39. DLA types were generated from 218 dogs for DRB1 and from 330 dogs for DQA1, while 181 dogs were characterised for both these loci. The frequency of individual DRB1 and DQA1 alleles showed considerable interbreed variation, e.g. 83% of West Highland White Terriers were DRB1*01 as opposed to 9% of Collies. No breed had >9 of the 22 DRB1 types defined in this study; several breeds had only two DRB1 types. DLA-DQA1 showed less variation in allele numbers per breed, but also showed considerable interbreed frequency variation. Haplotype analysis revealed over 44 different DRB1/DQA1 combinations. Of these, 25 were in a number of animals, and also in an animal that was homozygous for one or both of these loci. Some DRB1 alleles could be found in combination with several different DQA1 alleles, while others were only present in one haplotypic combination. DLA allele frequency data in normal dogs will be critical for disease association studies. It may also be possible to use haplotype data to establish the genetic relationships between different dog breeds.  相似文献   
137.
Carp (Cyprinus carpio L.) is a pest species in Australian waterways, and cyprinid herpesvirus 3 (CyHV‐3) is being considered as a potential biological control (biocontrol) agent. An important consideration for any such agent is its target specificity. In this study, the susceptibility to CyHV‐3 of a range of non‐target species (NTS) was tested. The NTS were as follows: 13 native Australian, and one introduced, fish species; a lamprey species; a crustacean; two native amphibian species (tadpole and mature stages); two native reptilian species; chickens; and laboratory mice. Animals were exposed to 100–1000 times the approximate minimum amount of CyHV‐3 required to cause disease in carp by intraperitoneal and/or bath challenge, and then examined clinically each day over the course of 28 days post‐challenge. There were no clinical signs, mortalities or histological evidence consistent with a viral infection in a wide taxonomic range of NTS. Furthermore, there was no molecular evidence of infection with CyHV‐3, and, in particular, all RT‐PCRs for viral mRNA were negative. As a consequence, the results encourage further investigation of CyHV‐3 as a potential biocontrol agent that is specific for carp.  相似文献   
138.
Tropical fisheries are among the most productive fisheries in the world, often providing the primary source of protein for the local population. Despite their importance, data on these systems are relatively limited, thus hampering management and policy development. Here, the implications of increasing fishing pressure are explored by critically evaluating the perceptions of the fishers who rely on these ecosystems to survive. A total of 169 fishers in 26 different fish‐dependent communities in the Tonlé Sap Lake, Cambodia, were surveyed to understand their perceptions of the impact that fishing has had on the ecosystem. The Tonlé Sap is one of the largest, yet poorest studied, freshwater fisheries in the world. Consistent with “fishing down the food web” theory of fisheries, survey data revealed that although fishers observed the total size of fish catch remaining consistent over recent years there has been a drastic decline in the size of individual fish, as well as a reduction in the diversity of species caught. These perceptions are examined with reference to food web theories that explore how fishing pressure leads to ecosystem change, including the more recent “indiscriminate fisheries” theory.  相似文献   
139.
The livelihoods of people dependent on the Tonle Sap floodplain ecosystem in Cambodia are expected to be affected by changes in economic conditions, social circumstances, environmental perturbations, demographic shifts and political climates. This study assesses how small‐scale fisheries’ livelihoods are changing in response to social and environmental conditions using the opinions of fishers collected through an intensive family survey of 514 households from Pursat and Battambang Provinces in Cambodia. Probit modelling approach was used to assess whether a fisher would continue fishing or not in the future when subjected to a variety of shifting conditions and identify the factors associated with their response. It was found that in any future condition about 50% of fishers would likely continue to fish, which suggests how much they love their traditional livelihood of fishing. The remaining 50% considered to diversify their livelihood strategy by shifting towards a combination of fishing, farming, and off‐farm jobs. Furthermore, the analysis found that the fishers will change their fishing practices depending on how other sectors in the region develop. The model showed increasing access to agricultural activities decreased the likelihood of continuing to fish, whereas finding an off‐farm job corresponded to increased likelihood of continuing to fish.  相似文献   
140.
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