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71.
In order to study the pathomorphology and immunohistochemistry of peste des petits ruminants, four goats and two sheep were inoculated intranasally with the Malig-Yemen strain of peste des petits ruminants virus. The animals developed fever, nasal discharge, oral erosions, cough and diarrhea. One goat and one sheep died and one moribund goat was killed. Three animals survived the infection. At necropsy, erosive stomatitis, pneumonia and gastroenteritis were found. Histopathologically the pneumonocytes and epithelial cells of the ileum had eosinophilic cytoplasmic and nuclear inclusions. By an indirect immunoperoxidase method, the nuclei and cytoplasm of the ileal epithelial cells of one goat contained positively (brown) stained antigen, which corresponded to viral nucleocapsids by electron microscopy. Virus appeared to be released through the microvilli of the epithelial cells. We also confirmed the formation of giant cells due to peste des petits ruminants virus.  相似文献   
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Sequential extraction processing (SEP) is a new approach to fractionating dried, flaked corn using 95% ethanol. In the original process, corn oil was extracted at 76°C in a countercurrent mode while simultaneously dehydrating the ethanol. This resulted in 20% of the protein (predominantly zein) coextracting with the oil. The process was modified to reduce the amount of coextracted protein. One modification (mSEP1) was to use a blend of 30% hexane and 70% ethanol at 56°C. A second modification (mSEP2) used a longer extraction column (L/D ratio 15) to replace the column with L/D 2 used in the original SEP system. To determine the effect of the modifications on oil quality, the quality of the crude corn oils produced from the modified SEP processes were compared with the quality of oil from the original SEP. To evaluate the quality of the three crude oils produced by SEP with the process typically used in industry, they were compared with the quality of laboratory hexane‐extracted corn oil. The results of the three SEP oils exhibited larger concentrations of fatty acids, phospholipids, and carotenoids, smaller concentrations of triacylglycerols, and darker red color than the hexane‐extracted oil. The oils from the two modified SEP processes contained smaller concentrations of free fatty acids and phospholipids and larger concentrations of triacylglycerols and carotenoids than the original SEP oil. In spite of the improvements to the oil through process modifications, the mSEP1 and mSEP2 oils exhibit greater refining losses than hexane‐extracted oil.  相似文献   
77.
This is the second of three articles that evaluate the consequences of using rollover protective structures (ROPS) on agricultural tractors. It presents the results of a decision analysis that compares three strategies for preventing injuries when agricultural tractors without ROPS overturn. The three strategies examined are "do nothing", "install ROPS", and "replace tractor". The strategies are implemented over a five-year period and health outcomes expressed as fatal and nonfatal injuries are calculated over a 23-year period. The "do nothing" strategy would result in 1,450 fatalities and 1,806 nonfatal injuries, while the "install ROPS" strategy would prevent 1,176 fatalities and 957 nonfatal injuries, and the "replace tractor" strategy would prevent 1,188 fatalities and 967 nonfatal injuries. The latter two strategies reflect more than an 80% reduction in fatalities and about 53% reduction in nonfatal injuries. The study does not consider overturn injuries that result from tractors lacking ROPS and for which ROPS are unavailable.  相似文献   
78.
The agricultural tractor was the principal source of fatal injury on American farms for the latter part of the 20th century, and they maintain that distinction today. Much has been learned about the toll of these fatalities and how to prevent them over the last ten years, yet public policy has generally been unsuccessful in reducing this toll. A policy conference entitled Tractor Risk Abatement and Control convened in 1997 to develop recommendations to reduce this death toll. Several stakeholders at the conference agreed on 25 action items, which if implemented would reduce the number of tractor-related deaths by more than 2,000 by the year 2015. These recommendations relate to tractor overturns, runovers, and traffic collisions as well as youth operators. This article addresses the completeness of a strategy for preventing tractor-related injuries for each of these four areas based upon an evaluation model derived from the Theory of Planned Behavior and an antecedent model. The ultimate result of this model is to influence an individual's intention to act to prevent injury. The set of recommendations was found to provide a coherent strategy. In addition, implementing the strategy at an organizational level is discussed.  相似文献   
79.
Global patterns of predator diversity in the open oceans   总被引:1,自引:0,他引:1  
The open oceans comprise most of the biosphere, yet patterns and trends of species diversity there are enigmatic. Here, we derive worldwide patterns of tuna and billfish diversity over the past 50 years, revealing distinct subtropical "hotspots" that appeared to hold generally for other predators and zooplankton. Diversity was positively correlated with thermal fronts and dissolved oxygen and a nonlinear function of temperature (approximately 25 degrees C optimum). Diversity declined between 10 and 50% in all oceans, a trend that coincided with increased fishing pressure, superimposed on strong El Ni?o-Southern Oscillation-driven variability across the Pacific. We conclude that predator diversity shows a predictable yet eroding pattern signaling ecosystem-wide changes linked to climate and fishing.  相似文献   
80.
OBJECTIVES: To determine whether there is a relationship between species-specific mitochondrial DNA (mtDNA), especially canine and feline mtDNA, and detectable amounts of pentobarbital in previously analyzed dog food samples. SAMPLE POPULATION: 31 dog food samples previously analyzed for pentobarbital (limit of detection, 1 microg/kg). PROCEDURE: Polymerase chain reaction (PCR) analysis was performed on dog food samples by use of PCR primers specific for either canine, feline, equine, bovine, porcine, ovine, or poultry mtDNA. RESULTS: PCR amplicons specific for feline or canine mtDNA at a 0.007% (70 microg/g [wt/wt basis]) or 0.0007% (7 microg/g) level, respectively, were not found in the 31 dog food samples. Most of the 31 dog food samples had a PCR amplicon on PCR analysis when a PCR primer set capable of simultaneously detecting mtDNA of cows, pigs, sheep, goats, deer, elk, and horses was used. Results of PCR analysis by use of primers specific for bovine, swine, sheep and goat, or horse mtDNA revealed amplicons specific for bovine or swine mtDNA only in 27 of the 31 samples. Analysis of the remaining 4 samples failed to yield amplicons for any mammalian mtDNA. Pentobarbital was detected in 2 of these 4 samples. Results of PCR analysis correlated with the stated ingredient list for most, but not all samples. CONCLUSIONS AND CLINICAL RELEVANCE: Because canine and feline mtDNA were not found in a set of retail dog food samples, these results indicate that the source of pentobarbital in dog food is something other than proteins from rendered pet remains.  相似文献   
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