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961.
A Field Trial of a Pilated Moraxella bovis Bacterin for the Prevention of Infectious Bovine Keratoconjunctivitis
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Bateman KG Leslie KE Scholl TP 《The Canadian veterinary journal. La revue veterinaire canadienne》1986,27(1):23-27
Two field trials were conducted to evaluate the efficacy of a Moraxella bovis bacterin in the control of infectious bovine keratoconjunctivitis. The bacterin did not affect the incidence of infectious bovine keratoconjunctivitis in either trial but did appear to reduce the severity of lesions, treatments required and withdrawals from pasture required in one trial. Possible reasons for the apparently contradictory results are offered. It is suggested that the bacterin may be of some value when used in conjunction with other preventive measures. 相似文献
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Colloidal aggregation and other random growth processes produce structures that behave differently from ordinary bulk matter. Much of this behavior can be described in terms of the invariance of the aggregates under changes of spatial length scale: they appear to be fractals. There are two types of basic mechanisms for producing fractal aggregates. Those in which aggregation proceeds cluster by cluster can be understood qualitatively in terms of a solvable schematic model. The diffusion-limited aggregation or deposition of individual particles to make a large cluster is not as well understood. It is closely related to several irreversible processes in other areas of physics, such as two-fluid displacement in porous materials and the dielectric breakdown of insulators. More generally, disorderly growth mechanisms provide structures having unique properties, many of which can be understood by using simple statistical principles. 相似文献
966.
Tannenbaum GS 《Science (New York, N.Y.)》1986,232(4755):1272-1273
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A Mayr 《Tier?rztliche Praxis》1986,14(2):237-244
The fundamentals of paramunization are briefly discussed to provide better understanding of paramunization of pigs. Veterinary practice and experimental studies demonstrate the usefulness, efficacy and harmlessness of paramunization of pigs. Mortality, morbidity as well as weight gain in piglets are used to evaluate the effect of the inducers PIND-AVI and/or PIND-ORF on piglets which have been treated shortly after birth. The therapeutic effect of paramunization has been studied in herds with enzootic pneumonia. Paramunization is especially suitable in stimulating the immune system, in treating immune deficiencies, in the prophylaxis of the stress syndrome (e.g. induced by transport, weaning, changing stalls, etc.) and in treating pluricausal, multifactorial infectious diseases such as enzootic pneumonia, rhinitis atrophicans, "crowding" disease. Paramunization of pigs is discussed, using PIND-ORF as an example of a biological inducer. Paramunization as a biological method to stimulate immunity provides a new concept of prophylaxis and therapy opposed to the uncontrolled use of chemicals in pig production. 相似文献
970.
Wallace G 《New Zealand veterinary journal》1986,34(11):197; discussion 197-197; discussion 198