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991.
Existing experimental data relating to the rate of recovery of the dose equivalent of sub-lethal damage are analysed. A precise determination of the half-life of the dose equivalent is found to be impossible, but all the evidence reviewed suggests that it is of the order of 1 or 2 hr for mammalian systems irradiated at normal body temperature and that, in such systems, little error is produced in dosage calculations by assuming a value of 1.5 hr to be applicable, as originally suggested by Lajtha & Oliver (1961).  相似文献   
992.
R. Dayal  Usha Kiran 《Hydrobiologia》1980,70(3):247-249
In this paper five polycentric chytrids have been described, Nowakowskiella elegans, N. profusa, Polychytrium sp., Catenaria anguillulae and Hyphochytrium catenoides. Of the five species described, N. profusa and Polychytrium sp. are new records from India.  相似文献   
993.
The architectural factor HMGI-C is of considerable interest for its recognized roles in mammalian development and tumorigenesis. As a result, the identification of downstream target genes of HMGI-C is the present focus of active research. In vitro evidence from macrophage cell lines has previously suggested that Hmgi-c is necessary for the inducible activation of MuRantes expression. To attempt to verify this hypothesis, an in vivo analysis was performed that took advantage of the existence of the Hmgi-c null mouse strain. The ability of cells and tissues extracted from Hmgi-c null mice to express the inflammatory chemokine MuRantes was investigated. The investigation examined MuRantes expression in primary embryonic fibroblasts and fresh peritoneal macrophages after Newcastle disease virus induction and whole organs after lipopolysaccharide induction. Each of these systems clearly demonstrates that Hmgi-c is not required for the activation of MuRantes expression.  相似文献   
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995.
Proline, an imino acid, has been well documented to be associated with the stress response induced by abiotic factors such as drought, cold and salinity in plants and biotic factors such as bacterial and fungal attacks. However, the regulatory mechanisms controlling proline metabolism, intercellular and intracellular transport and connections of proline to other metabolic pathways are poorly understood. F-MATCH analysis combined with composite module analysis (CMA) revealed that the binding sites matching matrices for O2 and OCSBF-1 were overrepresented in the promoters of differentially expressed proline metabolism genes. The presence of MYBAS1 consensus binding sites occurring in combination with O2 and OCSBF1 in the promoters of genes of proline biosynthesis pathway and SBF1 and GT1 consensus binding sites occurring in combination with O2 and OCSBF1 in the promoters of proline catabolic pathway genes suggest their involvement in modulation of proline metabolism and its accumulation in plants.  相似文献   
996.
In order to confirm the presence of immunoreactive insulin (IRI) in the serum of postmetamorphic Xenopus laevis, radioimmunoassay (RIA) methods were used. The concentration of hormone found in samples of blood serum taken from nonanaesthetized intact male and female animals by the guillotine method was 10.46 +/- 0.76 microU/ml. Significantly higher IRI concentrations were found in our intact animals anaesthetized in MS 222 at pH 3.5 (21.9 microU/ml) compared with intact controls anaesthetized in MS 222 adjusted to pH 7.0 (14.4 microU/ml). During the wound-healing stage subsequent to forelimb amputation in the experimental cases (0 hours to 3 days) anaesthetized in MS 222 pH 7.0, there were intervals of significantly elevated serum IRI followed by a period of decreased IRI concentration compared with the levels in anaesthetized (MS 222 pH 7.0) and nonanaesthetized intact controls. These fluctuations were due, presumably, to stress caused by amputational injury and/or anaesthetic. Serum IRI increased steadily from 3 to 14 days postamputation then remained stable for the balance of the regeneration period (28 days) compared with nonanesthetized intact controls. A positive correlation was found between immunoreactive insulin and glucose levels in the serum of our animals. However, no correlation exists between serum IRI levels and serum osmolality in the data.  相似文献   
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Biological Trace Element Research - Bone is a passive storage organ for zinc, which contains about 30% of the total body zinc. However, during extreme zinc deficiency, only a small fraction of zinc...  相似文献   
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