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排序方式: 共有10000条查询结果,搜索用时 359 毫秒
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L K 《Science (New York, N.Y.)》1987,237(4819):1237-1238
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The "solar neutrino puzzle" has been a challenge for almost 20 years, posing broad and fundamental questions about astrophysics and neutrino properties. This article sketches some of the ideas that have been put forward to solve the problem. These ideas can be grouped into two main classes: those involving changes in the standard solar model or in the basic nuclear reaction data, and those that attribute the puzzle to as yet unobserved properties of the neutrinos. 相似文献
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1. Brown egg layers were fed diets differing in oil content, oil source and linoleic acid concentration and the effect on performance from 22 to 69 weeks of age was studied.
2. The birds responded with an increasing mean egg weight up to a linoleic acid intake of 2.75 g/bird d.
3. Increasing the intake of readily absorbable oil without increasing linoleic acid concentration did not increase mean egg weight. 相似文献
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Mastitis Caused by Haemophilus somnus in a Dairy Cow 总被引:2,自引:1,他引:1
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A survey of carcass condemnation at a poultry abattoir and its application to disease management 总被引:1,自引:1,他引:0
Ansong-Danquah J 《The Canadian veterinary journal. La revue veterinaire canadienne》1987,28(1-2):53-56
During a five year period, slaughter records were maintained on flocks of broiler chickens sent to a federally-inspected abattoir in New Brunswick. These records, including data regarding condemnation of both carcasses and portions of broilers, were maintained at the level of the individual producer. Annual meetings and ad hoc consultations with producers, a veterinary poultry specialist, and support groups in the poultry industry (feed mills, breeders, etc.) were used to relay to the various interested parties, information relating to disease conditions.
Following the implementation of this system, condemnation rates dropped by one full percentage point during the first three years, with a slight increase observed during the last two years of the study. At the end of the survey, condemnation rates were 20% less than those of the national average.
相似文献