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Demyelinating encephalomyelopathy associated with lead poisoning in nonhuman primates 总被引:4,自引:0,他引:4
Lead poisoning was diagnosed in four primates by the finding of toxic amounts of lead in tissues. Abnormalities in the brain and spinal cord were characterized by vascular lesions and demyelination. These findings suggest a new animal model for the study of demyelination and strengthen the supposition that lead may be a factor in some idiopathic demyelinating diseases. 相似文献
97.
Reichle HG Beck SM Haynes RE Hesketh WD Holland JA Hypes WD Orr HD Sherrill RT Wallio HA Casas JC Saylor MS Gormsen BB 《Science (New York, N.Y.)》1982,218(4576):1024-1026
During the second flight of the space shuttle, the measurement of air pollution from satellites (MAPS) experiment in the OSTA-1 payload acquired approximately 35 hours of radiometric measurements of the carbon monoxide mixing ratio in the middle troposphere, upper troposphere, and lower stratosphere. A gas filter radiometer operating in the 4.67-micrometer band was used to acquire the data over the region from 38 degrees N to 38 degrees S during both daytime and nighttime. The performance of the measurement system was excellent. The data reduced to date indicate the presence of significant gradients in the middle tropospheric carbon monoxide mixing ratio with both latitude and longitude over the North Atlantic, the Mediterranean Sea, and the Middle East. On the basis of comparisons with directly measured values, the accuracy of the measurements is approximately 15 percent. Comparisons of data taken on successive orbits over the same geographic region indicate that the repeatability of the measurements is approximately 5 percent. 相似文献
98.
It is established that wild and synanthropic waterfowl of the order Anseriformes (gadwell, mallard, graylag goose, teal, garganey, etc.) are possible sources of mixed invasions i.e., an etiological factor in forming and maintaining ill-being of domestic geese with respect to the following diseases: echinostomatidosis, amidostomosis, ganguleterikidosis, thominxosis, streptocarosis, echinuriosis, as well as ectoparasites (bird lice). 相似文献
99.
Highly extensible Escherichia coli DNA molecules in planar extensional flow were visualized in dilute solution by fluorescence microscopy. For a narrow range of flow strengths, the molecules were found in either a coiled or highly extended conformation, depending on the deformation history of the polymer. This conformation hysteresis persists for many polymer relaxation times and is due to conformation-dependent hydrodynamic forces. Polymer conformational free-energy landscapes were calculated from computer simulations and show two free-energy minima for flow strengths near the coil-stretch transition. Hysteresis cycles may directly influence bulk-solution stresses and the development of stress-strain relations for dilute polymer flows. 相似文献
100.
A rapid method for staining R. orientalis is described. Smears of infected tissues are defatted and stained in a dilute aqueous solution of methylene blue and basic fuchsin. Smears thus stained show R. orientalis as blue organisms on a pinkish-purple background. 相似文献