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21.
Fox AD 《Journal of the American Veterinary Medical Association》2003,223(7):948; author reply 948
22.
Immunogenicity of bovine parainfluenza type 3 virus proteins encapsulated in nanoparticle vaccines,following intranasal administration to mice 总被引:2,自引:0,他引:2
Shephard MJ Todd D Adair BM Po AL Mackie DP Scott EM 《Research in veterinary science》2003,74(2):187-190
Stimulation of long lasting, protective immunity to respiratory viruses is often difficult to achieve with conventional respiratory vaccines. Polymeric nanoparticles, incorporating viral proteins have been shown to offer sustained release of antigen, with consequent prolongued stimulation of the respiratory immune system. In this paper the efficacy of two nanoparticle vaccines (poly-lactide-co-glycolide, PLGA; polymethylmethacrylate, PMMA), incorporating proteins of bovine parainfluenza type 3 virus (BPI-3) was investigated. As a preliminary to experiments in calves, it was considered essential to demonstrate immunogenicity of the experimental vaccine in mice. Mice immunised with PLGA nanoparticles, containing BPI-3 proteins, developed higher levels of virus-specific antibody than mice immunised with the PMMA vaccine or with soluble viral proteins alone. Immunoblotting using serum from the vaccinated mice, demonstrated strong reactions against the major BPI-3 proteins. 相似文献
23.
OBJECTIVE: To determine the effect of osteotomy angle, reduction technique, and tibial plateau rotation angle on angular and rotational limb deformities. STUDY DESIGN: Geometric comparison using bone models. METHODS: Rotational osteotomies were made in the proximal metaphysis of artificial tibias at 0 degrees, 10 degrees, 20 degrees, -10 degrees, and -20 degrees from perpendicular with respect to either the proximodistal and craniocaudal tibial axes. Negative-numbered angles represented osteotomies made from distal to proximal or caudal to cranial. Changes in tibial angulation and torsion were measured using a 3-dimensional digitizing instrument at tibial plateau rotation angles from 0 degrees to 30 degrees at 5 degrees increments. Two osteotomy reduction techniques were used: complete osteotomy reduction and alignment of the medial cortex. The mean of 5 measurements of torsional and angular tibial deformity for each of the 9 osteotomy orientations in each reduction technique group was obtained. RESULTS: All had increasing angular and rotational deformity as tibial plateau rotation angle increased. In the medially aligned cortex group, all tibias had valgus deformity, and 8 of 9 tibias were internally rotated. In the reduced osteotomy group, minimal angular deformity was seen in tibias with osteotomy variation along the proximodistal axis; however, tibias with osteotomy variation along the craniocaudal axis had angular deformity ranging from 6.0 degrees of varus deformity to 14.3 degrees of valgus deformity. Rotational deformity was affected similarly by osteotomy variation along either axis. Reduction technique had greater affect on angular and rotational deformity than osteotomy angle variation. CLINICAL RELEVANCE: These results suggest that osteotomy reduction may play a greater role in angular and rotational deformity than osteotomy angle, although extreme osteotomy angles should be avoided. To decrease the severity of deformity, we recommend that the osteotomy be made perpendicular to the craniocaudal and proximodistal axes and be completely reduced with less regard for alignment of the medial cortex. 相似文献
24.
Meinkoth JH Kocan AA Loud SD Lorenz MD 《Journal of the American Veterinary Medical Association》2002,220(2):185-189
OBJECTIVE: To characterize clinical and hematologic responses in dogs following experimental inoculation with Babesia gibsoni-like isolates from infected dogs in Oklahoma. DESIGN: Prospective study. ANIMALS: 6 mixed-breed dogs. PROCEDURE: 2 dogs were inoculated with organisms from a naturally infected dog, and 3 were inoculated with organisms from a second naturally infected dog (1 of these 3 dogs was splenectomized 1 week prior to inoculation). One dog was not inoculated. Complete blood counts were performed weekly. RESULTS: In the 5 dogs inoculated with organisms, parasites were initially detected 1 to 5 weeks after inoculation, and severity of parasitemia peaked with 1.9 to 6.0% of RBC infected by 4 to 6 weeks after inoculation. Parasitemia was easily detectable (> 0.1% of RBC infected) for 3 to 4 weeks. Clinical abnormalities included lethargy, fever, and pale mucous membranes but were mild to nearly inapparent in 2 dogs. All dogs developed regenerative anemia and marked thrombocytopenia. Thrombocytopenia developed before and lasted longer than the parasitemia. Profound but transient neutropenia was detected in some dogs. The splenectomized dog developed more severe parasitemia and anemia and more pronounced clinical abnormalities. Three dogs with intact spleens recovered without treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that 2 or more genotypically distinct, but morphologically identical, small Babesia parasites can infect dogs in the United States. Compared with infection with small Babesia parasites from California, infection with these isolates resulted in less severe parasitemia and clinical abnormalities. Parasitemia was transient, indicating that identification of organisms in blood smears may be difficult in some dogs. 相似文献
25.
Abstract We have previously shown that both atopic and normal dogs generate an IgG response to antigens of Malassezia pachydermatis . The aim of this study was to compare IgE responses to separated proteins of M. pachydermatis in 28 atopic dogs with Malassezia dermatitis and 22 clinically normal dogs using Western immunoblotting. Six different detection systems were evaluated in order to assess sensitivity and eliminate nonspecific binding and cross-reactivity. The protocol yielding the best results utilized a monoclonal mouse antidog IgE, an alkaline phosphatase conjugated goat antimouse IgG which had been passed through a canine IgG column 3 times, a chemiluminescent substrate and a digital imaging system. Proteins of 45, 52, 56 and 63 kDa were recognized by more than 50% of the atopic dog sera and thus represented major allergens. Only a minority of normal dogs showed faint IgE binding to these proteins. The results indicate that the majority of atopic dogs with Malassezia dermatitis have a greater IgE response than normal dogs, suggesting an IgE-mediated immune response may be clinically important in the pathogenesis of the disease. 相似文献
26.
Extra-cellular enzyme production of different Phaeoacremonium spp. and Phaemoniella chlamydospora isolates were used to assay the possibility of inter-specific characterisation. Isolates of Phaeoacremonium aleophilum, Phaeoacremonium angustius, P. viticola and Ph. chlamydospora were grown on solid media and the activities of extra-cellular amylases, lipases, proteases, cellulases, xylanases, laccase, polygalacturonase, pectate lyase, lignin peroxidase, manganese peroxidase, urease and chitinase were assayed. Phaeoacremonium species showed activities of a larger number of enzymes and also enzyme activity was frequently higher suggesting that Phaeoacremonium can be more virulent. To assay if the produced extra-cellular enzymes could reflect the virulence capacity of the two genera, calluses of Vitis vinifera L. (cvs. Baga and Maria Gomes) and of a rootstock (R3309) were inoculated with filtrated culture liquid medium of three isolates of Ph. chlamydospora and one of P. angustius. Filtrates from all strains decreased callus growth and membrane integrity, while soluble protein content of calluses decreased with the strains CAP 054 and 1AS. P. angustius (CAP 054) induced the more severe symptoms in all genotypes. Water content decreased together with an increase of osmolality in both cultivars but not in rootstock suggesting that osmorregulatory capacity is more affected in cultivars. Data show that: (1) Phaeoacremonium and Phaeomoniella genera have different patterns of extra- cellular enzymatic production; (2) these fungi produce extra-cellular compound(s) that induce(s) senescence symptoms in plant cells inhibiting callus proliferation; (3) among the strains tested in plant calluses the most virulent isolate (CAP 054) also produced higher amounts of some extra-cellular enzymes; (5) rootstock calluses were less sensitive to inoculation than grapevine calluses. 相似文献
27.
Prediction of multinomial probability of land use change using a bisection decomposition and logistic regression 总被引:1,自引:1,他引:1
Land use change is an important research area in landscape ecology and urban development. Prediction of land use change (urban
development) provides critical information for making the right policies and management plans in order to maintain and improve
ecosystem and city functions. Logistic regression is a widely used method to predict binomial probabilities of land use change
when just two responses (change and no-change) are considered. However, in practice, more than two types of change are encountered
and multinomial probabilities are therefore needed. The existing methods for predicting multinomial probabilities have limits
in building multinomial probability models and are often based on improper assumptions. This is due to the lack of proper
methodology and inadequate software. In this study, a procedure has been developed for building models to predict the multinomial
probabilities of land use change and urban development. The foundation of this procedure consists of a special bisection decomposition
system for the decomposition of multiple-class systems to bi-class systems, conditional probability inference, and logistic
regression for binomial probability models. A case study of urban development has been conducted to evaluate this procedure.
The evaluation results demonstrated that different samples and bisection decomposition systems led to very similar quality
and performance in the developed multinomial probability models, which indicates the high stability of the proposed procedure
for this case study. 相似文献
28.
29.
30.
Jae-Cheol Nam Deb J. Fish Alan J. Thorpe Soon-Ung Park 《Water, air, and soil pollution》2001,130(1-4):361-366
A quantitative study of the amount of air transported between the boundary layer and the free atmosphere is important for understanding air quality and upper tropospheric ozone, which is a greenhouse gas. Frontal systems are known to be an effective mechanism for the vertical transport of pollutants. Numerical experiments have been performed with a simple two-dimensional front model to simulate vertical transport of trace gases within developing cold fronts. Three different trace gases experiments have been done numerically according to the different initial fields of trace gases such as aerosol, ozone and H2O2. Trace gas field tilts to the east while the front tilts to the west. Aerosol simulation shows that pollutants can be transported out of the boundary to altitudes of about 10 km. The stratospheric ozone is brought downwards in a tropopause fold behind of the frontal surface. The meridional gradient in trace gas (H2O2) can cause a complicate structure in the trace field by the meridional advection. 相似文献