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1.
Cerebellar disease in an adult cow   总被引:1,自引:0,他引:1       下载免费PDF全文
This is the report of clinical signs and lesions of a cerebellar disorder in an adult four year old Limousin cow grazing perennial ryegrass (Lolium perenne). The most striking histopathological lesion was a marked paucity of Purkinje cells throughout the cerebellum.  相似文献   
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Pulsed laser deposition (PLD) is a conceptually and experimentally simple yet highly versatile tool for thin-film and multilayer research. Its advantages for the film growth of oxides and other chemically complex materials include stoichiometric transfer, growth from an energetic beam, reactive deposition, and inherent simplicity for the growth of multilayered structures. With the use of PLD, artificially layered materials and metastable phases have been created and their properties varied by control of the layer thicknesses. In situ monitoring techniques have provided information about the role of energetic species in the formation of ultrahard phases and in the doping of semiconductors. Cluster-assembled nanocrystalline and composite films offer opportunities to control and produce new combinations of properties with PLD.  相似文献   
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Cryptosporidiosis in neonatal calves: 277 cases (1986-1987)   总被引:2,自引:0,他引:2  
From January 1986 through December 1987, 277 cases of cryptosporidiosis in calves were diagnosed by the South Dakota State University Diagnostic Laboratory. Cryptosporidium sp was the only pathogen identified in 142 (51.3%) of the calves. Concurrent infections with rotavirus, coronavirus, Escherichia coli, Salmonella sp, bovine viral diarrhea virus, or other pathogens were identified in the remaining 135 calves. After elimination of cases involving autolyzed specimens or calves with chronic diarrhea, records of 11 calves with acute, severe cryptosporidiosis were identified in which Cryptosporidium sp was the only pathogen.  相似文献   
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The levels of blood-plasma testosterone were studied in the adult light bodied strain cocks. Blood was sampled (1 ml) from the wing vein by means of a heparinized syringe six times within a 24-hour interval. The plasma obtained by centrifugation was kept in a refrigerator at a temperature of --18 degrees C. Testosterone was determined by the radioimmunological method. The testosterone levels were significantly higher (P less than 0.001), 18.8 nmol/l on the average, in the blood samples taken during the dark period of the day (10 o'clock p.m., 2 and 6 o'clock a.m.) than in the samples taken in the light part of the day (8 and 10 o'clock a.m., 2 o'clock p.m.) when the average concentration of the studied hormone was 10.7 nmol/l of plasma. the lowest levels of testosterone were recorded in the morning and the highest values were recorded late in the evening (10 o'clock p.m.). The differences in the levels of the hormone between sampling terms indicate that the testosterone level in adult animals shows diurnal variances. It was found by the study of the concentration of testosterone in the blood plasma of the same individuals within short intervals of time (30-60 min) that testosterone secretion in adult cocks had a pulsatory manner. The evaluation of hormone levels should include not only the diurnal variances but also the pulsatory manner of testosterone secretion.  相似文献   
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