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Myelography using pantopaque in greater than usual amount with a variation in technique, which is described, is believed to provide increased accuracy in differential diagnosis and precise localization of lesions in the lumbar spine. The need for multiple space exploration is eliminated and more detailed information concerning the size and shape of lesions is provided as compared to that secured by the use of 3 or 6 cc. of opaque medium and fluoroscopic examination alone. In 53 cases in which lumbar myelography was performed and the diagnosis verified or disproved at operation, there was a 5 per cent diagnostic error in 41 instances in which the method outlined was used, as compared with 17 per cent error in 12 cases in which only 3 or 6 cc. of radiopaque material and fluoroscopy alone were used. The accuracy of the procedure would appear to warrant its use in the evaluation of patients suspected of having abnormalities of the lumbar discs associated with nerve root compression. 相似文献
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Synthesis and intracellular transport of protein by the colleterial gland of the cecropia silkmoth 总被引:1,自引:0,他引:1
The tubular portion of the colleterial gland of the cecropia silkmoth secretes protein which labels extensively with glycine and appears as a single peak when separated by acrylamide gel electrophoresis. The radioactive peak does not stain with protein stains or absorb at 280 nm, but is dispersed by Pronase digestion. Synthesis of the peak is sensitive to inhibition by puromycin and cycloheximide but is not sensitive to actinomycin or chloramphenicol inhibition. Amino acid analysis revealed a composition of 30% glycine, 33% aspartic acid, and insignificant amounts of aromatic amino acids; the molecular weight was calculated to be 160,000. Autoradiographic analysis revealed that nearly all the glycine incorporated is transported from the mature secretory cells, and the half-time of secretion is calculated to be 3.4 hr. The possible use of this product as a marker for biochemical differentiation is discussed. 相似文献
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Summary Soil temperature, moisture, and CO2 were monitored at four sites along an elevation transect in the eastern Mojave Desert from January to October, 1987. Climate appeared to be the major factor controlling CO2 partial pressures, primarily through its influence of rates of biological reactions, vegetation densities, and organic matter production. With increasing elevation, and increasing actual evapotranspiration, the organic C, plant density, and the CO2 content of the soils increased. Between January and May, soil CO2 concentrations at a given site were closely related to variations in soil temperature. In July and October, temperatures had little effect on CO2, presumably due to low soil moisture levels. Up to 75% of litter placed in the field in March was lost by October whereas, for the 3 lower elevations, less than 10% of the litter placed in the field in April was lost through decomposition processes. 相似文献
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