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61.
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The presence or absence of light during flotation restricted environmental stimulation: Effects on plasma cortisol,blood pressure,and mood 总被引:1,自引:0,他引:1
John W. Turner Jr. Thomas Fine Gina Ewy Peter Sershon Thomas Freundlich 《Applied psychophysiology and biofeedback》1989,14(4):291-300
This study examined the effect of light on relaxation associated with flotation restricted environmental stimulation therapy (REST), as measured by plasma cortisol, mean arterial pressure, and psychometric parameters. Twenty-one subjects were paired by baseline cortisol levels into two groups: one experiencing flotation REST in the presence of light (REST-L) and one experiencing flotation REST in the absence of light (REST-D). Subjects were 15 male and 6 female students aged 22–28 in normal health who had not experienced REST. Repeated flotation REST (8 sessions) either with light or without light was associated with a decrease in plasma cortisol and a decrease in mean arterial pressure, with no differences in effectiveness between groups. The psychometric assessment of mood, using the POMS scale, before and after sessions 1 and 8 revealed mood state improvement in both REST-L and REST-D groups. These data suggest that the presence of light did not compromise the flotation REST experience, as evidenced by the lack of difference between REST-L and REST-D groups. 相似文献
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Summary We report on the size distribution of clones marked by mitotic recombination induced by several different doses of X-rays applied to 72 h oldDrosophila larvae. The results indicate that the radiation significantly reduces the number of cells which undergo normal proliferation in the imaginal wing disc. We estimate that 1000 r reduces by 40–60% the number of cells capable of making a normal contribution to the development of the adult wing. Part of this reduction is due to severe curtailment in the proliferative ability of cells which nevertheless remain capable of adult differentiation; this effect is possibly due to radiation-induced aneuploidy. Cytological evidence suggests that immediate cell death also occurs as a result of radiation doses as low as 100 r. The surviving cells are stimulated to undergo additional proliferation in response to the X-ray damage so that the result is the differentiation of a normal wing. 相似文献
66.
Characterization of B and H blood-group active glycosphingolipids from human B erythrocyte membranes
Peter Hanfland 《Chemistry and physics of lipids》1975,15(2):105-124
Two blood group B active glycosphingolipids (B-I and B-II) previously isolated and highly purified from human B erythrocytes [21] were analysed first by degradation with α-D-galactosidase from coffee beans, α-L-fucosidase from bovine kidney and with 0,1 N trichloracetic acid; the native B-glycolipids as well as their degradation products were then investigated by methylation analysis with combined gas chromatography-mass spectrometry, by thin layer chromatography, twodimensional immunodiffusion and by the hemagglutination inhibition technique. Together with the results obtained by mass spectrometry of permethylated glycolipids [26] the following structures were elucidated: α-D-galactopyranosyl-(1 → 3)-[α-L-fucopyranosyl-(1 → 2)]-D-galactopyranosyl-(1 → 4)-N-acetyl-D-glucosaminosyl-(1 → 3)-D-galactopyranosyl-(1 → 4)-D-glucopyranosyl-(1 → 1)-ceramide for the B-I glycosphingolipid and α-D-galactopyranosyl-(1 → 3)-[α-L-fucopyranosyl-(1 → 2)]-D-galactopyranosyl-(1 → 4)-N-acetyl-D-glucosaminosyl-(1 → 3)-D-galactopyranosyl-(1 → 4)-N-acetyl-D-glucosaminosyl-(1 → 3)-D-galactopyranosyl-(1 → 4)-D-glucopyranosyl-(1 → 1)-ceramide for the B-II glycosphingolipid. A H active glycolipid fraction from B erythrocytes further purified by thin layer chromatography was also investigated by methylation analysis. The pattern of its partially methylated alditol acetates was essentially the same as that of the α-galactosidase treated and permethylated B-I glycolipid. It also exhibited strongly precipitating and hemagglutination inhibiting H properties as well as the two α-galactosidase treated B-I and B-II glycosphingolipids. Based upon these data the following tentative structure was proposed: α-L-fucopyranosyl-(1 → 2)-D-galactopyranosyl-(1 → 4)-N-acetyl-D-glucosaminosyl-(1 → 3)-D-galactopyranosyl-(1 → 4)-D-glucopyranosyl-(1 → 1)-ceramide. Gas chromatographic analysis revealed sphingosine and lignoceric, nervonic and behenic acids to be the main components of the ceramide residues of the three glycosphingolipids. From the data presented the H active substance very probably can be regarded as the immediate precursor of the B-I glycosphingolipid from human B erythrocyte membranes. 相似文献
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Peter W. Van Arsdale 《American anthropologist》2003,105(2):409-410
Healing the Modern in. Central Javanese City. Steve Ferzacca. Durham, NC: Carolina Academic Press, 2001. 280 pp. 相似文献
69.
Mauro S. Sandrin K. Erin Lovering George Tachas Peter R. Collins Ian F. C. McKenzie 《Immunogenetics》1987,25(5):279-283
Human DNA was transfected into mouse L cells and tk+ HuLy-m2+ (= CD7+) transfectants isolated after growth in hypoxanthine, aminopterin, thymidine medium and repeated cloning. After several cycles of transfection, > 90% of HuLy-m2+ L cells could be detected, by rosetting and by cytofluorography, which showed the transfectants to have a density of CD7 two to five times that found on peripheral blood lymphocytes. Despite this, the 37 kd CD7+ dimer could only be identified with difficulty using cell-surface radioiodination and sodium dodecyl sulfate-polyacrylamide gel electrophoresis techniques. An antiserum was produced (C3H anti-HuLy-m2+ L cells) which, after absorption, was shown to react with HuLy-m2 antigens present on human thymocytes and lymphocytes and on CD7+ transfected L cells.Abbreviations BSA
bovine serum albumin
- DME
Dulbecco's modified Eagle's medium
- EDTA
ethylenediamine-tetraacetate
- HAT
hypoxanthine, aminopterin, thymidine
- HSV
herpes simplex virus
- PBL
peripheral blood lymphocyte
- PBS
phosphate-buffered saline
- RFC
rosette-forming cell
- SDS-PAGE
sodium dodecyl sulfate-polyacrylamide gel electrophoresis
- tk
thymidine kinase 相似文献
70.