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101.
The influence of the swine major histocompatibility genes on antibody and cell-mediated immune responses to immunization with an aromatic-dependent mutant of Salmonella typhimurium. 下载免费PDF全文
J S Lumsden B W Kennedy B A Mallard B N Wilkie 《Canadian journal of veterinary research》1993,57(1):14-18
Eighty-two major histocompatibility complex (MHC) swine leukocyte antigen (SLA) defined miniature pigs from 16 litters were examined for serum agglutinating antibody titer and O-polysaccharide (O-ps) specific peripheral blood lymphocyte blastogenesis following two parenteral vaccinations with 1 x 10(8) aromatic-dependent (aroA) Salmonella typhimurium and following oral challenge with 1 x 10(12) virulent parent S. typhimurium. Least mean squares analysis allowed separate determinations of the effects of MHC genotype, dam, sire and litter. In most cases only litter significantly influenced both lymphocyte blastogenesis and antibody titer before and after vaccination and following challenge. However, pig SLA haplotype significantly influenced the degree of O-ps specific lymphocyte proliferation six days after the second vaccination (p < 0.004). Lymphocyte proliferation and serum agglutinating antibody response six days after primary vaccination were negatively correlated (r2 = -0.68, p < 0.001). In most cases, "dd" and "gg" homozygous and "dg" heterozygous pigs, having the same MHC class II region, behaved immunologically as a group distinct from the other genotypes. 相似文献
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Wilkie JS 《The Canadian veterinary journal. La revue veterinaire canadienne》1982,23(6):197-199
The lesions in two cases of necrotic colitis in old cats are described. Both had gross lesions of a necrotic, hemorrhagic colitis without gross lesions in the small intestine. Histologically the lesions resembled those of feline panleukopenia virus infection, namely: necrosis and loss of crypt epithelium, dilation of crypts and lining of crypts by flattened epithelium, subsequent collapse of the lamina propria and hemorrhage from subepithelial capillaries. Both grossly and histologically these lesions were restricted to the colon without similar involvement of the small intestine.The histories and clinical signs, the virological and hematological studies suggest that feline panleukopenia virus was not the etiological agent in these cases. No other causal agent was identified. 相似文献
104.
The failure of fisheries science to preserve life in the oceans is broadly recognized. Here, we argue that part of this failure is the result of the philosophical basis behind fisheries science. In the middle of the 20th century, synthesizing more than half a century of insights dealing with what they called the 'overfishing problem', British scholars gave birth to some of the first predictive fishery management tools. Although novel for their time, the main objective of the approach was to advise the fishing industry on how to maximize the exploitation of fish resources without jeopardizing the viability of fish populations. Half a century on from these first attempts, we need a wider historical perspective to understand species dynamics, both natural and anthropogenic. We are also aware that there are other benefits society obtains from the ocean than maximum sustainable catches and we need to understand the role of biodiversity in social welfare. Not only should fishing be regarded as an economic activity but also as a planetary-scale human experiment that requires experimental controls for a continuous evaluation of its performance and effects. Here, we present a philosophical approach to the problem, synthesizing material from the different disciplines that we consider should be addressed. A mix of insights may best help to deal with the 'overfishing problem.' 相似文献
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Yanjun Xie Callum A. S. Hill Zefang Xiao Carsten Mai Holger Militz 《Wood Science and Technology》2011,45(1):49-61
The dynamic water vapour sorption properties of Scots pine (Pinus sylvestris L.) wood samples were studied to investigate the modifying effects of glutaraldehyde. Pine sapwood was treated with solutions
of glutaraldehyde and a catalyst (magnesium chloride) to obtain weight per cent gains of 0.5, 8.6, 15.5, and 21.0%, respectively.
The sorption behaviour of untreated and treated wood was measured using a Dynamic Vapour Sorption apparatus. The results showed
considerable reduction in equilibrium moisture content of wood and the corresponding equilibrium time at each target relative
humidity (RH) due to glutaraldehyde treatment. The moisture adsorption and desorption rates of modified and unmodified wood
were generally faster in the low RH range (up to approximate 20%) than in the high range. Modification primarily reduced the
adsorption and desorption rates over the high RH range of 20–95%. Glutaraldehyde modification resulted in a reduction in sorption
hysteresis due to the loss of elasticity of cell walls. 相似文献
109.
The infectivity of 15 cryopreserved Theileria spp. sporozoite stabilates was assessed semi-quantitatively by titration using naive peripheral blood mononuclear cells (PBM) in vitro in multi-well plates. Using the method described, the effective dilution, which would result in 50% of replicate wells infected (ED50), was calculated. The ED50 for 11 Theileria annulata stabilates in bovine PBM ranged from 10(-2.6) to 10(-4.2) dilutions of 1 tick equivalent (t.e.) ml(-1), one stabilate of Theileria parva 10(-2.2)t.e.ml(-1); and three Theileria lestoquardi stabilates in ovine PBM, from 10(-1.5) to 10(-1.8)t.e.ml(-1). Two of the T. annulata stabilates had been used individually to infect groups of calves: stabilate 52 produced more severe disease responses than stabilate 67, as measured by prepatent period, parasitosis, parasitaemia and death or recovery. This corresponded with the sixfold difference found in vitro between the ED50's of these two stabilates. This method is useful not only to measure the infection potential of the sporozoite stabilates but also as an in vitro model for chemotherapeutic and immunological studies of the early stages of theileriosis. 相似文献
110.
Four horses treated for ocular squamous cell carcinoma (SCC) that subsequently developed local tumour extension or local metastases without ocular recurrence are included in this study. Medical records were examined and long‐term follow‐up obtained through contact with owners and referring veterinarians. In 2 horses, SCC developed in the nasolacrimal duct and maxillary sinus one and 3.5 years, respectively, after treatment for SCC in the medial canthus of the eye. No recurrence of the SCC was noted in the ocular structures. Both were treated successfully with surgery and radiation therapy. Two additional horses had delayed metastasis of SCC to the parotid lymph node one and 2 years after excision of the ipsilateral third eyelid for SCC. No recurrence of the SCC was noted in the ocular structures. One was treated with surgery and radiation without success and one was not treated. Ocular SCC can spread to local tissues or lymph nodes without recurrence in the eye. The clinical manifestation of tumour recurrence may be delayed. Delayed local extension or local metastasis in horses after ocular SCC without recurrence in the eye itself has not been previously reported. Clinical signs of ocular squamous cell carcinoma should prompt immediate treatment and local recurrence despite successful treatment of the ocular disease is a possibility. 相似文献