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In 0.05--0.1 mmol.l-1 concentration, bilirubin inhibits ADP-activated respiration of isolated liver mitochondria; it has no effect on respiration in the absence of ADP. Bilirubin-induced inhibition of respiration is not abolished by serum albumin, but bilirubin bound to serum albumin and the photodegradation products of bilirubin have no inhibitory effect.  相似文献   
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The biological activity of the filtrates of 29 C. difficile strains was studied in vivo (suckling white mice) and in vitro (cell cultures of different species and origin). The action of the filtrates on the experimental models in vivo was evaluated from the cytotoxic effect index, while in vitro the intensity of the cytotoxic effect was evaluated from the percentage of dead cells in the monolayer. The results of the comparative determination of toxicity characteristics in vivo and in vitro demonstrated that cell cultures were more sensitive experimental models than suckling white mice. The use of cell cultures permitted the quantitative evaluation of the cytotoxic activity of the filtrates under study, as well as the detection of their cell-directed action at minimal concentrations.  相似文献   
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The genetic structure of 65 chicken populations was studied using 29 simple sequence repeat loci. Six main clusters which corresponded to geographical origins and histories were identified: Brown Egg Layers; predominantly Broilers; native Chinese breeds or breeds with recent Asian origin; predominantly breeds of European derivation; a small cluster containing populations with no common history and populations that had breeding history with White Leghorn. Another group of populations that shared their genome with several clusters was defined as 'Multi-clusters'. Gallus gallus gallus (Multi-clusters), one of the subspecies of the Red Jungle Fowl, which was previously suggested to be one of the ancestors of the domesticated chicken, has almost no shared loci with European and White Egg layer populations. In a further sub-clustering of the populations, discrimination between all the 65 populations was possible, and relationships between each were suggested. The genetic variation between populations was found to account for about 34% of the total genetic variation, 11% of the variation being between clusters and 23% being between populations within clusters. The suggested clusters may assist in future studies of genetic aspects of the chicken gene pool.  相似文献   
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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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Electron microscopy of mouse neocortex was carried out during rehabilitation following long-term protein-caloric deficiency. Food rehabilitation led to partial recovery of brain ultrastructure, however, a high neuronal level of secondary lysosoms and lipofuscin bodies was preserved, with the changes in the spine apparatus and synaptic contacts persisting in neuropile. Carnitine addition to food during rehabilitation increased the number of free ribosomes in cortical neurons. A substantial development of granular endoplasmic reticulum was observed. A greater number of spine apparatus cisterns was detected, however, like in conventional rehabilitation, the width of synaptic clefts and postsynaptic densities remained narrower than in control mice.  相似文献   
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