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Using benzo(a)pyrene (BaP) as a probe for aryl hydrocarbon hydroxylase (AHH) activity, differences in mixed-function oxidase (MFO) activity were observed using microspectrofluorimetry in single living cells during long term treatment with 3-methylcholanthrene (3-MC) or carbaryl. Although these two compounds differ in chemical structure, similar effects were observed in 3T3 cell populations. The results suggest that the two compounds activate the same enzymatic system and that individual cells of a supposed homogeneous cell population are not equally sensitive to xenobiotics, i.e. subpopulations were observed which have differences in AHH activity. 相似文献
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W J Allard C D Cheli D L Morris J Goldblatt Y Pierre L Kish Y Chen J Dai R L Vessella D W Chan M K Schwartz Z Zhou K K Yeung 《The International journal of biological markers》1999,14(2):73-83
We conducted a multicenter evaluation of the analytical and clinical performance of the automated Bayer Immuno 1 complexed PSA (cPSA) assay, and compared assay performance to the Bayer Immuno 1 PSA assay. We sought to determine whether measurements of cPSA could be of clinical utility in the management of patients with prostate cancer. Results of the 10-day imprecision across three evaluation sites produced total CV < 2.50% and an analytical sensitivity of 0.02 microgram/L. There was an increased trend in clinical sensitivity for prostate cancer with increasing stage of disease (71-86%). Clinical specificity for patients with benign urogenital disease was 74.8%, and for other nonprostate diseases ranged from 91.1-100%. Retrospective serial monitoring of 155 patients with prostate cancer demonstrated concordance of cPSA measurements to clinical status for 97% of the patients analyzed. Results from the clinical studies using the Bayer Immuno 1 cPSA assay were comparable to results obtained with the Bayer Immuno 1 PSA assay. The Bayer Immuno 1 cPSA assay demonstrates analytical performance and clinical effectiveness in the management of prostate cancer patients during the course of disease and therapy. 相似文献
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Using the imidate procedure, 2,3,4,6-tetra-O-benzyl-1-O-(N-methylacetimidoyl)-β-d-galactopyranose was condensed with various monosaccharides to provide, in good yield and with high stereoselectivity, α-linked disaccharides. 相似文献
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Pierre Fellmann Jens Andersen Philippe F. Devaux Marc le Maire Alain Bienvenue 《Biochemical and biophysical research communications》1980,95(1):289-295
A spin labeled fatty acid (16-doxylstearic acid) was linked to a photochemical reacting group (azido derivative). When the molecule is introduced, at a low concentration, into rabbit sarcoplasmic reticulum membranes, the spectrum before illumination is identical to the spectrum obtained with the corresponding spin labeled fatty acid. After illumination, a large immobilized components is seen. It corresponds to about 70% of the ESR signal of the effectively bound label, at room temperature. The fraction of immobilized component varies with temperature, from 100% at 0°C to 50% at 35°C. Addition of a small amount of detergent (dodecyl octaethylene glycol monoether), under non solubilizing conditions, decreases the fraction of signal due to a strongly immobilized probe. A possible interpretation is that the immobilized signal reflects protein bound spin labels trapped in Ca2+ ATPase oligomers, which are partially dissociated by detergent addition or temperature increase. 相似文献
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Pierre Bongrand Gilles Bouvenot Robert Bartolin J Jeanne Tatossian Bernard Bruguerolle 《Chronobiology international》1988,5(1):81-83
Eleven male subjects were investigated to detect a possible circadian rhythm of the polymorphonuclear phagocytosis. Both cell activity and serum opsonins were studied for numerical detection of granulocytes having ingested at least one particle and for the mean number of ingested particles per cell. No significant temporal differences (ANOVA and cosinor) were found. 相似文献
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Pierre Livet 《PSN》2003,1(1):45-52
Every emotion can be characterized by its temporal dynamics, which also allow emotions to be categorised. Emotions, understood as resulting from the perception of a difference between expectations and the observed consequences of a course of action, are constantly interacting with cognitive processes that underlie these emotions and react to them. This is the case, in particular, for revision processes concerning one’s beliefs. In this view, anxiety can be understood as a signal of a difficulty to revise profoundly one’s beliefs, which explains the tendency to make only small revisions. Resistance to revision (of beliefs or preferences) can also be an indication of one’s values. It is mainly at the level of affective attitudes (with longer temporal scope and requiring deeper revisions) that mental diseases can be observed and can be described from the standpoint of their own strategies of revision. 相似文献
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