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We have compared the species richness of medicinal plants and the differential patterns of use amongst settlements in the Andean communities of Northwest Argentina which have differing levels of isolation. About 259 ethnoespecies, belonging to 74 plant families, were included, representing between 70 and 80% of the total estimate. The results indicate that Coronopus didymus is the most relevant and important species. The method of use of medicinal plants and the ailments treated by rural doctors compared to those of the layperson is different. Native and exotic plants are used differently according to the body system treated. There are some relationships between internal and external use and body systems and recipes. The greater medicinal species richness found in the less isolated locations is due to external enriching cultural influences.  相似文献   
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Location within a tree was analyzed as a source of variation in Sequoia sempervirens leaf monoterpenes. No differences were found for quantitative composition or total yield/dry wt among lower, middle and upper canopy positions. The awlshaped, spirally arranged leaves of vigorous upper shoots showed small quantitative compositional differences, but not differences in total yield. The intermediate leaf form of young sprouts had the most different monoterpene quantitative composition and about three times the total yield of the above two leaf forms. Analysis of a clonal ring of 17 adult trees resulted in coefficients of variation similar to those for samples collected from different canopy levels of the same shoot. Results revealed the sources and magnitudes of experimental error in comparative studies of this species' leaf monoterpenes, and did not support the concept that somatic mutation provides an important source of variation in a large, long-lived organism such as coast redwood.  相似文献   
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Characterization of Newly Formed and Aged Granules in the Neurohypophysis   总被引:1,自引:0,他引:1  
Neurosecretory granules from the rat and bovine neurohypophysis were isolated and some of their biochemical and biophysical properties studied. Neurosecretory granules (NSG) from rat neurohypophysis were labeled, in vivo, with [35S]cysteine and isolated on isoosmotic gradients. Whereas 1 day after labeling most of the radioactivity was found in the lower part of the gradient, 35 days later the isotope was also located in the lighter NSG-containing fraction. Different analytical procedures showed that the lighter fraction, both in bovine and rat NSG, contain more subpopulations of neurophysin-like material than the heavier fraction. The first material to be released during stimulation of secretion, in vivo or in vitro, is mobilized from the heavy NSG. Isolation of rat NSG, at different times during and after dehydration of the animals, reveals that the newly synthesized material is found in the heavy NSG-containing fraction. Furthermore, the results indicate that the newly synthesized NSG are more resistant to lysis than the lighter granules. The results are discussed in relation to the maturation and degradation processes of the granule content and to the functional state of the NSG.  相似文献   
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