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991.
Thompson RC 《Veterinary parasitology》2004,126(1-2):15-35
The taxonomy and molecular epidemiology of Giardia and Giardia infections are reviewed in the context of zoonotic and waterborne transmission. Evidence to support the zoonotic transmission of Giardia is very strong, but how frequent such transmission occurs and under what circumstances, have yet to be determined. Zoonotic origin for waterborne outbreaks of Giardia infection appears to be uncommon. Similarly, livestock are unlikely to be an important source of infection in humans. The greatest risk of zoonotic transmission appears to be from companion animals such as dogs and cats, although further studies are required in different endemic foci in order to determine the frequency of such transmission. 相似文献
992.
Rodriguez DB Mackin A Easley R Boyle CR Hou W Langston C Walsh AM Province MA McLeod HL 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2004,18(3):339-345
Thiopurine methyltransferase (TPMT) produces inactive metabolites of azathioprine and, in humans, has a variable amount of activity. Humans with low TPMT activity commonly develop myelotoxicity when receiving azathioprine. Our study sought to characterize the distribution of TPMT activity in a population of dogs and to determine whether the pretreatment knowledge of red blood cell (RBC) TPMT activity could predict myelotoxicity in dogs receiving azathioprine. RBC TPMT activity was measured in 299 healthy dogs, and 9 dogs that represented a wide range of enzyme activity received azathioprine at a standard therapeutic dose for 30 days. TPMT activity in healthy dogs was log normally distributed and varied over an approximately 7-fold range. Geometric mean, minimum, and maximum RBC TPMT activities were 37.1, 16.3, and 115 nmol per gram of hemoglobin (gHb) per hour, respectively. TPMT deficiency was not identified. Two populations of TPMT activity in dogs were detected by statistical modeling (commingling analysis). Dogs with intermediate TPMT activity (14-38 nmol/gHb/h) receiving azathioprine had significantly lower neutrophil counts during week 4 than during weeks 0-3, whereas those with high activity (>39 nmol/gHb/h) did not have a significant change in neutrophil count. An analysis of TPMT activity in 6 dogs with a history of azathioprine-associated myelotoxicity in a clinical setting revealed either intermediate or high TPMT enzyme activity in all dogs, suggesting that TPMT activity, as measured in RBCs, is not the sole cause of severe azathioprine-associated myelosuppression in dogs. 相似文献
993.
994.
A periocular nodular sarcoid of the right upper and lower eyelids was diagnosed in an 11-year-old Thoroughbred mare. Computed tomography scan revealed the extent of the tumor. The mass was surgically debulked under general anesthesia, and the affected periocular region was injected intralesionally with Bacillus of Calmette and Guerin (BCG). An emulsion of cell wall fractions was used, which has been modified to reduce the toxic and allergic effect, but retain the antitumor activity. In total, five injections were performed at 2-week intervals. At follow-up 7 months after the last BCG injection, the tumor was completely resolved. Two years after the last treatment, the horse remains tumor-free. 相似文献
995.
ABSTRACT A murine hybridoma cell line GD2 secreting an immunoglobulin (Ig)M monoclonal antibody (MAb) was produced against surface antigens from an anastomosis group (AG) 4 isolate of Rhizoctonia solani (teleomorph: Thanatephorus cucumeris). Ascites were produced in mice using GD2 hybridoma cells and used to develop a rapid immunochromatographic lateral flow device (LFD) for the detection of antigens from R. solani and certain related Rhizoctonia spp. The LFD was tested for specificity against surface antigens from related and unrelated soil fungi. Antigens from representative isolates of R. solani AGs 1, 2-1, 2-3, 2-t, 3, 4, 5, 6, 7, 8, 9, 10, 11, and BI gave a positive response in LFD tests, as did antigens from Thanatephorus orchidicola, T. praticola, R. fragariae (teleomorph: Ceratorhiza fragariae), Ceratorhiza goodyerae-repentis, Ceratobasidium cornigerum, and binucleate AGE. Antigens from R. solani AGs 2-2, 2-2IIIB, and 2-2IV and from the related fungi R. carotae, R. cerealis (teleomorph: Ceratobasium cereale), R. crocorum (teleomorph: Helicobasidium brebissonii), R. oryzae (teleomorph Waitea circinata), and R. zeae gave negative responses, as did antigens from a range of unrelated fungi and oomycetes including Fusarium, Gliocladium, Trichoderma, Pythium, and Phytophthora spp. The usefulness of the LFD to detect R. solani was demonstrated in soils naturally infested with R. solani AG3. There was close agreement between results of LFD tests and conventional plate enrichment tests employing selective medium. The specificity of the technique was confirmed by polymerase chain reaction PCR using R. solani AG3-specific primers and by analyses based on sequences of the internal transcribed spacer (ITS)1-5.8S-ITS2 rRNA-encoding regions of unrelated fungi recovered from soil samples. The LFD was used to quantify R. solani AG4 in artificially infested soil samples (chopped potato soil inoculum). Estimates of CFU per gram of soil were derived using a most-probable number technique, which was based on the presence or absence of a detectable signal in the LFD. Estimates of CFU obtained in LFD tests and those obtained in a plate-trapped antigen enzyme-linked immunosorbent assay incorporating MAb GD2 were identical (449 CFU g(-1) of soil). 相似文献
996.
Gyrodactylus thymalli Zitnan, 1960 and G. salaris Malmberg, 1957 have an indistinguishable ribosomal internal transcribed spacer (ITS) DNA sequence, but exhibit surprisingly high levels of intra- and interspecific sequence variation of the mitochondrial cytochrome oxidase I (CO1) gene. To test whether different populations of these reportedly very similar species could be discriminated using morphometric methods, we examined the morphometry of four different populations representing different mitochondrial clades. Twenty five point-to-point measurements, including five new characters of the attachment hooks, were recorded from three Norwegian laboratory populations (G. salaris from the Rivers Lierelva and Rauma, and G. thymalli from the River Rena), and from one wild population of G. thymalli from the River Test, UK. The Norwegian populations were kept under identical environmental conditions to control for the influence of temperature on the haptoral attachment hooks. Data were subsequently subjected to univariate and linear stepwise discriminant analyses. The model generated by the linear stepwise discriminant analysis used 18 of the 25 original variables, the first two roots accounting for 96.6% of the total variation between specimens. The hamulus shaft length accounts for 66.7% of the overall correct classification efficiency. Based on morphometry, all specimens were assigned to the correct species. Apart from three specimens of G. salaris from the River Lierelva population which were misclassified as belonging to the G. salaris Rauma population, all specimens were assigned to the correct population. Thus, populations of Gyrodactylus identified by mtDNA can also be discriminated using morphometric landmark distances. 相似文献
997.
Peter A. Burrough John P. Wilson Pauline F.M. van Gaans Andrew J. Hansen 《Landscape Ecology》2001,16(6):523-546
Previous attempts to quantify topographic controls on vegetation have often been frustrated by issues concerning the number of variables of interest and the tendency of classification methods to create discrete classes though species have overlapping property sets (niches). Methods of fuzzy k-means classification have been used to address class overlap in ecological and geographical data but previously their usefulness has been limited when data sets are large or include artefacts that may occur through the derivation of topo-climatic attributes from gridded digital elevation models. This paper presents ways to overcome these limitations using GIS, spatial sampling methods, fuzzy k-means classification, and statistical modelling of the derived stream topology. Using data from a ca. 3600 km2 forested site in the Greater Yellowstone Area, we demonstrate the creation of meaningful, spatially coherent topo-climatic classes through a fuzzy k-means classification of topo-climatic data derived from 100 m gridded digital elevation models (DEMs); these classes were successfully extrapolated to adjacent areas covering a total of ca. 10000 km2. Independently derived land cover data and middle infrared corrected Landsat TM derived estimates of Normalised Difference Vegetation Index (M_NDVI) at 575 independently sampled sites were used to evaluate the topo-climatic classes and test their extrapolation to the larger area. Relations between topo-climatic classes and land cover were tested by 2 analysis which demonstrated strong associations between topo-climatic class and 11 of the 15 cover classes. Relations between M_NDVI and topo-climatic classes proved to be stronger than relations between M_NDVI and the independent cover classes. We conclude that the fuzzy k-means procedure yields sensible and stable topo-climatic classes that can be used for the rapid mapping of large areas. The value of these methods for quantifying topographic controls on biodiversity and the strength of their relations with computed NDVI values warrant further investigation. 相似文献
998.
Strubbe DT Brooks DE Schultz GS Willis-Goulet H Gelatt KN Andrew SE Kallberg ME MacKay EO Collante WR 《Veterinary ophthalmology》2000,3(2-3):111-119
Ulcerative keratitis is a common and potentially blinding ocular disease of horses, capable of progressing to corneal perforation in as little as 24 h. This rapid stromal degeneration is mediated in part by exogenous and endogenous proteinases. We measured and compared the concentrations of two matrix metalloproteinases (MMP-2 and MMP-9) and a serine proteinase (neutrophil elastase) present in the precorneal tear film of normal horses and horses with rapidly progressing ulcerative keratitis. Precorneal tear film samples were collected from 23 ulcerated and 21 unaffected eyes of 23 horses with unilateral ulcerative keratitis, and from 33 normal eyes of 17 control horses. MMP-2, MMP-9, and neutrophil elastase were identified by casein and gelatin zymography and quantified by computerized image analysis. Median MMP-9 levels were significantly higher in the precorneal tear film of young control horses vs. older control horses ( P = 0.005). Median MMP-2, MMP-9, and neutrophil elastase levels were significantly higher in the precorneal tear film of ulcerated eyes when compared to age-matched normal controls ( P = 0.004, P = 0.001, and P = 0.012, respectively). Median MMP-2 levels were also significantly higher in the precorneal tear film of contralateral eyes of affected horses when compared to age-matched normal controls ( P = 0.004). No significant differences in median proteinase levels were detected between 'sterile' ulcers and those from which bacteria or mixed infections (bacteria and fungi) were isolated. However, median MMP-2 and neutrophil elastase levels were significantly higher in the precorneal tear film of eyes with 'sterile' ulcers when compared with ulcerated eyes from which fungi were isolated ( P < 0.05). The results of this study support the use of topical antiproteinase therapy which targets both MMPs and serine proteinases in progressive equine ulcerative keratitis. 相似文献
999.
1000.
Higgins R 《The Canadian veterinary journal. La revue veterinaire canadienne》2000,41(2):105-116
A list of the different bacterial and fungal agents isolated from marine mammals in different parts of the world is presented. Importance is given to some of the most recently identified bacterial agents, including Actinobacillus delphinicola, A. scotiae, and Brucella spp. A list, in alphabetical order, of bacteria recovered from different tissues or organs from marine mammals is presented for the integumentary, respiratory, digestive, genitourinary, and reticuloendothelial systems. Infectious bacterial agents associated with abscesses and with cases of septicemia are also listed. Information about the different fungal agents recovered from marine mammals is summarized. A section covering some of the zoonotic infectious agents recovered from marine mammals is included. 相似文献