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171.
Sixteen beagle dogs were injected intradermally with Rickettsia rickettsii. The dogs were divided into four groups (n=4):1) infected, non-treated withdoxycycline;3) infected, treated with doxycycline and an anti-inflammatory dose of corticosteroid;4) infected, treated with ocular fluoresein angiograhphy was performed on days 6, 10, 17 post-inoculatin.A mild interstitial lung opacitywas noted in4/16 dogs on day 6, 5/16 on day 10 and 17 post-inculatin. Increased retinal vascular permeability was noted n 8/16 dogs on day 6,3/16 on day 10 and 1/16 on day 17 post-inoculation. Correlatin between the presence of radiographic and retinal lesions was not signigicant (p=0.08). Elevan, naturally infected, dogs with thoracic radiographs and an final diagnosis of RMSF were also evluated. Four of the 11 dogs had an unstructu4red inteerstitial pattern. Dogs with acute, experimentally-infected or naturally-occurring RMSF may have subtle pulmonary changes characterized by an unstructured interstitial patteern.  相似文献   
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An 11-year-old Siamese cat with an osteogenic sarcoma of the nasal cavity was treated by partial surgical excision followed by a course of high dose-per-fraction radiation therapy in conjuction with metronidazole, a hypoxic cell sensitizer. Four thousand two hundred rads were delivered to the tumor in 7 weekly fractions. Each treatment was preceded by 6 gm/m2 oral metronidazole given 3 hours before irradiation. There were no untoward side effects and the cat was in remission 2 years after treatment.  相似文献   
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The anti-bacterial activity of 13 commercially available acaricides, in use in the Caribbean, was tested against Dermatophilus congolensis, an actinomycete involved in streptothricosis of cattle, sheep and goats in the tropics. Acaricides used included organochloride, organophosphorus, carbamate, pyrethroid and amidine compounds. Each acaricide was tested at a typical working dilution used by the farmers, at 25 degrees C and 37 degrees C, in the presence or absence of 15 percent newborn calf serum as a fouling agent. Fouling of acaricides was found to have a marked inhibitory effect on its anti-bacterial activity. Vapona and Cattle Washing Detergent were found to be more active against Dermatophilus congolensis than the other acaricides tested.  相似文献   
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Mycoplasma synoviae is an important causative agent of avian mycoplasmosis. In the present study the conserved domain of the variable lipoprotein and hemagglutinin (vlhA) gene of M. synoviae was sequenced and analyzed for 19 field strains of M. synoviae isolated from chickens across Japan. This analysis revealed that there were at least nine genotypes of M. synoviae present in Japan. Furthermore, we found a single nucleotide polymorphism (SNP) within this region in all the Japanese isolates, and based on this finding, we established a PCR method with cycling probe technology to differentiate between these field isolates and the live M. synoviae vaccine strain Mycoplasma synoviae-H (MS-H).  相似文献   
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Objective – To describe the different forms of digital radiography (DR), image file formats, supporting equipment and services required for DR, storage of digital images, and teleradiology. Background – Purchasing a DR system is a major investment for a veterinary practice. Types of DR systems include computed radiography, charge coupled devices, and direct or indirect DR. Comparison of workflow for analog and DR is presented. Summary – On the surface, switching to DR involves the purchase of DR acquisition hardware. The X‐ray machine, table and grids used in analog radiography are the same for DR. Realistically, a considerable infrastructure supports the image acquisition hardware. This infrastructure includes monitors, computer workstations, a robust computer network and internet connection, a plan for storage and back up of images, and service contracts. Advantages of DR compared with analog radiography include improved image quality (when used properly), ease of use (more forgiving to the errors of radiographic technique), speed of making a complete study (important for critically ill patients), fewer repeat radiographs, less time looking for imaging studies, less physical storage space, and the ability to easily send images for consultation. Conclusions – With an understanding of the infrastructure requirements, capabilities and limitations of DR, an informed veterinary practice should be better able to make a sound decision about transitioning to DR.  相似文献   
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