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961.
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
962.
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
963.
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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965.
966.
A 29 year old man was admitted 36 hours after ingesting about 5 g paraquat. His arterial oxygen pressure fell progressively to 3.4 kPa (34 mm Hg), and pulmonary damage induced by paraquat was diagnosed. His condition did not improve after treatment with prednisolone and cyclophosphamide, but after irradiation both lungs cleared and arterial oxygen pressure started to improve. Irradiation of the lungs should be considered in patients who, after surviving the acute phase of poisoning with paraquat, show progressive deterioration of respiratory function. 相似文献
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970.
M. P. Rayson A. Davies D. G. Bell E. S. Rhodes-James 《European journal of applied physiology and occupational physiology》1995,71(5):405-408
Heart rate (beats · min–1;f
c) measured during marching with a load is often used to predict the oxygen cost (1·min–1; VO2) of the activity. The prediction comes from thef
c/VO2 relationship determined from laboratory measures off
c and VO2 during treadmill running. Studies in men have suggested that this may not be appropriate although this has yet to be examined in women. This study, therefore, compared thef
c/VO2 relationship between loaded marching and maximal running protocols in women. Sixteen female subjects [mean (SD), age 21.9 (2.3) years, height 6 (0.06) m, weight 62.6 (7.6) kg] had theirf
c (from three-lead chest electrodes) and VO2 measured first during standard treadmill run protocols, and again 1 week later during loaded marching protocols. The slopes and intercepts determined from linear regression off
c on VO2 for each individual for each protocol were compared as were the maximalf
c(f
cmax), VO2 and ratings of perceived exertion (RPE) from the last work period of each protocol in pairedt-tests. The VO2 slopes (P < 0.01) and intercepts (P < 0.05) differed significantly between loaded marching and running.f
cmax for loaded marching were 90% off
cmax for running (P < 0.01) and VO2 for loaded marching were 80% of those for running (P < 0.01). However, RPE at the final levels for the two protocols were not significantly different. The data suggest that in women the VO2 relationships for loaded marching and for running are different. This difference is similar to that found in men when speed is held constant and the load and gradient are varied. The results suggest that it would be erroneous to usef
c and VO2 measured during running protocols in the laboratory to estimate energy expenditure and work intensity during loaded marching in the filed. 相似文献