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Monoclonal antibodies have become powerful tools in immunology and biotechnology during the last decade. They are successfully used in a lot of fields in parasitology. This paper gives an overview of difficulties currently associated with immunodiagnosis of Sarcocystis infections and of the production and characterization of monoclonal antibodies for the investigation of problems that could not be solved by classical methods.  相似文献   
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In 1975 the buzzard (Buteo buteo) was found to be the final host of Frenkelia clethrionomyobuteonis. After this discovery it became possible to investigate systematically the pathomorphology of the infection in the intermediate host, the bank vole (Clethrionomys glareolus). Fifty bank voles were infected orally with a suspension of sporocysts recovered from the faeces of experimentally infected buzzards. Each rodent receive 7000 sporocysts. Six controls each were given a faecal suspension from a non-infected buzzard. The voles were killed between 1 and 140 days after infection and examined histologically. Between the 5th and 8th day of the infection during the schizogonic multiplication of the parasite a focal necrosis of liver cells and of the liver parenchyma is observed followed by a reversible resorptive inflammation associated with siderophagia and the occurrence of giant cells. The spleen was spodogenously enlarged up to twice its normal size. There also was haemosiderosis of the bone marrow, the liver and the spleen up to 25 days after infection. At the same time the erythropoiesis in the bone morrow, the spleen and in the lymph nodes increased; there also was a lymphoid hyperplasia in spleen and lymph nodes. About 10 days after infection a reversible infiltration with lymphocytes and plasma cells developed in the liver, heart and brain. This infiltration was again detectable as perivascular and meningeal reactions in the brain after the 49th day after infection. The second asexual multiplication of the parasite was seen histologically in the grey and white matter of the central nervous system after the 18th day of infection. The developing cysts increased in size continuously thereby compressing the surrounding nervous tissue. Disseminated focal necrosis with resorptive inflammatory components was prominent in the parenchyma of the brain after the 49th day of infection. It was possible to differentiate between damage in single organs and systemic pathological lesions. The lesions in single organs were directly connected with the development of parasitic stages in the liver (schizonts) and in the brain (cysts). The generalized lesions occurred in the haemopoietic system after an impairment of the blood during the first asexual multiplication. They also occurred in the immunocytic systems after the first and during the second asexual multiplication and during the relatively late cystic phase of the parasite in the brain. The pathogenesis of the disintegration of blood cells is not clear. The immunocytic reaction can be considered an immunological response of the host against the parasite. The effect of the development of the cysts on the function and structure of the central nervous system is expected to lead to an increasing impairment of the motility of the intermediate host.  相似文献   
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OBJECTIVE: To calculate normative joint angle, intersegmental forces, moment of force, and mechanical power at elbow, antebrachiocarpal, and metacarpophalangeal joints of dogs at a walk. ANIMALS: 6 clinically normal mixed-breed dogs. PROCEDURE: Kinetic data were collected via a force platform, and kinematic data were collected from forelimbs by use of 3-dimensional videography. Length, location of the center of mass, total mass, and mass moment of inertia about the center of mass were determined for each of 4 segments of the forelimb. Kinematic data and inertial properties were combined with vertical and craniocaudal ground reaction forces to calculate sagittal plane forces and moments across joints of interest throughout stance phase. Mechanical power was calculated as the product of net joint moment and the angular velocity. Joint angles were calculated directly from kinematic data. RESULTS: All joint intersegmental forces were similar to ground reaction forces, with a decrease in magnitude the more proximal the location of each joint. Flexor moments were observed at metacarpophalangeal and antebrachiocarpal joints, and extensor moments were observed at elbow and shoulder joints, which provided a net extensor support moment for the forelimb. Typical profiles of work existed for each joint. CONCLUSIONS AND CLINICAL RELEVANCE: For clinically normal dogs of a similar size at a walk, inverse dynamic calculation of intersegmental forces, moments of force, and mechanical power for forelimb joints yielded values of consistent patterns and magnitudes. These values may be used for comparison in evaluations of gait in other studies and in treatment of dogs with forelimb musculoskeletal disease.  相似文献   
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Between 1993 and 2003, 713 (24%) of 2,940 dead Florida manatees (Trichechus manatus latirostris) recovered from Florida waters and examined were killed by watercraft-induced trauma. It was determined that this mortality was the result of watercraft trauma because the external wound patterns and the internal lesions seen during gross necropsy are recognizable and diagnostic. This study documents the methods used in determining watercraft-related mortality during gross necropsy and explains why these findings are diagnostic. Watercraft can inflict sharp- and blunt-force trauma to manatees, and both types of trauma can lead to mortality. This mortality may be a direct result of the sharp and blunt forces or from the chronic effects resulting from either force. In cases in which death is caused by a chronic wound-related complication, the original incident is usually considered to be the cause of death. Once a cause of death is determined, it is recorded in an extensive database and is used by Federal and state managers in developing strategies for the conservation of the manatee. Common sequelae to watercraft-induced trauma include skin lesions, torn muscles, fractured and luxated bones, lacerated internal organs, hemothorax, pneumothorax, pyothorax, hydrothorax, abdominal hemorrhage and ascites, and pyoperitoneum.  相似文献   
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Anti-Toxoplasma antibody titres in 185 sera from clinically normal goats from 14 farms were assayed by both the latex agglutination and the indirect fluorescent antibody tests. The animals were of various breeds including Angora, New Zealand feral, Angora×feral, Saanen and Toggenburg. A high level of agreement between the two tests was obtained with 83.8% of titres corresponding to within one dilution and 96.8% to within two dilutions. In both tests, titres of 1:64 and above were considered positive. A total of 298 goat sera from clinically normal kids (n = 88), yearlings (n = 65) and adults (n = 145) from 17 farms were examined by the latex agglutination test. The prevalence of positive sera was 7% in kids, 23% in yearlings and 37% in adults. There was a significantly higher prevalence of positive sera in dairy than in fibre breeds.  相似文献   
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49 of 102 sheep of one production herd, which had returned to oestrus once or twice within the 1985 breeding season, were treated twice in a nine-day interval with the PGF2 alpha analogue Cloprostenol "Jenapharm". 53 animals received an additional dose of 10 micrograms of Gonavet "Berlin-Chemie". A lambing rate of merely 15% was achieved by subsequent term-oriented artificial insemination. 31 sheep still in oestrus one day after term-oriented artificial insemination were served, bringing the lambing rate from synchronisation of oestrus and ovulation to 26% and the lambing result to 154%. Serving of the remaining sheep in 2 subsequent oestric cycles, on balance, yielded lambing rates and results of the remaining sheep in 2 subsequent oestric cycles, on balance, yielded lambing rates and results which were higher with significance than those recorded from untreated sheep in the same herd.  相似文献   
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