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排序方式: 共有6950条查询结果,搜索用时 15 毫秒
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Matthew I. Daws Jennifer Davies Hugh W. Pritchard Neville A. C. Brown Johannes Van Staden 《Plant Growth Regulation》2007,51(1):73-82
We tested the applicability of the recently identified major germination cue from smoke (a butenolide 3-methyl-2Hfuro[2,3-c]pyran-2-one) on 18 weed species from non-fire prone environments. For the study species we compared the relative effectiveness
of alternating temperatures, KNO3, GA3, smoke water and the butenolide on germination percentage, germination rate and seedling mass. We found that while smoke
stimulated germination in a number of species it also had negative impacts on other species. In addition, the butenolide was
effective on the widest range of species in terms of enhancing germination percentage, rate and seedling mass. However, none
of the treatments, including butenolide were effective on all species. Our data demonstrate that butenolide may have wide
applicability as a germination and seedling growth stimulant irrespective of whether the species come from fire-prone habitats. 相似文献
995.
E Subramanian I D Swan D R Davies 《Biochemical and biophysical research communications》1976,68(3):875-880
An electron density map for the pepsin-like enzyme from Rhizopus chinensis has been calculated at 5.5Å resolution. The molecular boundary has been defined and certain secondary structural details have been inferred. The molecule is bilobal and has a large cleft in which several inhibitors have been observed to bind. 相似文献
996.
Lisa Clayton Christopher Hiley Simon Davies Richard D'souza Peter Jones Richard Strange Geoffrey Aber 《Free radical research》1992,17(4):271-278
The sensitivity of isolated glomeruli from normotensive (Wistar-Kyoto, WKY) and spontaneously hypertensive (SHR) strains to oxidant stress was studied by determining the incidence of pyknosis, karyohexis and karyolysis after incubation with different concentrations of hydrogen peroxide (H2O2) (4.7 × 10-9-10-3 M). Even though the proportion of glomeruli containing nuclei that demonstrated these features increased progressively with increasing concentrations of H2O2, the number of severely damaged glomeruli was relatively small even at concentrations of 4.7 × 10-3 M.
Examination of the surface epithelial cells of glomeruli using scanning electron microscopy revealed no evidence of disturbance of the macroscopic or podocyte structure or, of increased blebbing after H2O2-treatment. These data suggest damage to nuclei is an early result of ROS stress on glomeruli.
Preincubation of WKY glomeruli with captopril or lisinopril resulted in a significant drop in the proportion of WKY glomeruli demonstrating structural damage after oxidant stress. In contrast, preincubation of SHR glomeruli with lisinopril had no effect on oxidant-induced changes in the morphology of SHR glomeruli, whereas captopril effected a significant increase in the proportion of glomeruli demonstrating damage at all concentrations of H2O2. 相似文献
Examination of the surface epithelial cells of glomeruli using scanning electron microscopy revealed no evidence of disturbance of the macroscopic or podocyte structure or, of increased blebbing after H2O2-treatment. These data suggest damage to nuclei is an early result of ROS stress on glomeruli.
Preincubation of WKY glomeruli with captopril or lisinopril resulted in a significant drop in the proportion of WKY glomeruli demonstrating structural damage after oxidant stress. In contrast, preincubation of SHR glomeruli with lisinopril had no effect on oxidant-induced changes in the morphology of SHR glomeruli, whereas captopril effected a significant increase in the proportion of glomeruli demonstrating damage at all concentrations of H2O2. 相似文献
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998.
Cyst wall, brood capsules and evaginated protoscoleces of E. granulosus (ovine and equine) and E. multilocularis were fixed in 10% formol-saline, embedded in paraffin and cut at 8 micrometer. Specific rabbit antisera to antigen 5 and antigen B of hydatid cyst fluid were used with immunoperoxidase methods to localise the antigens in the histological sections. Antigen 5 was found in all parasites and was associated with cells of the subtegumental area of the protoscolex, the brood capsule wall and the germinal membrane. The labelled antigen appeared as distinct granules in all areas. It is suggested that antigen 5 may be synthesised in all of these sites and that a source of the antigen in cyst fluid may be the germinal and brood capsule membranes. The laminated membranes of E. granulosus (ovine and equine) were, except for the superficial layers, free from antigen 5. Antigen B was present in all parasites. It was distributed diffusely throughout the laminated membrane, germinal membrane and brood capsule wall. There were areas of densely labelled antigen B on the surface of the distal cytoplasm of the protoscolex tegument and the surface of calcareous corpuscles. The distribution of antigen B in relation to PAS positive material and possible complement activating substances is discussed. The laminated membrane of E. granulosus was apparently more permeable to antigen B than to antigen 5. It is suggested that differences in the diffusion of these antigens through the laminated membranes of hydatid cysts in the same or different host species may account for variable serological responses during infection. 相似文献
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