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Combined exposure of mice to a mixture of chemicals in small quantities and gamma-radiation at a total dose of 30 sGy cause partial summation of biological effects assessed by cytogenetic disorders in nuclear cells of the bone marrow and changes in erythrocyte metabolism. The level of cytogenetic damages in bone marrow cells remained increased till day 14 of recovery, whereas following exposure to chemicals or radiation alone the number of chromosomal aberrations (ChA) was nearly same as in control at this point of recovery The anaphase method showed prevalence of ChA in the form of fragments over bridges in marrow karyocites. The combination of factors suppressed energy-producing processes in erythrocytes (reliable reductions in lactate dehydrogenase and lactate) and activated oxidation processes (reliable decrease in reduced glutathione). Functional shifts in erythrocyte metabolism persisted till day 30 of recovery Based on results of the investigation, functional status of organism following low-intensity exposures can be assessed, along with cytogenetic, also by indices of erythrocyte metabolism.  相似文献   
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Inclusion of ketonazole (in a daily dose of 400 mg/kg for 8 days) into the diet of intact and cholesterol-fed (5% dietary cholesterol) rats produced a respective 20- and 30-percent lowering of cholesterol content in blood serum. In all the animals, the hypocholesterolemic effect of ketoconazole was realized via a decrease of the concentration of very low and low density lipoproteins. Ketoconazole also gave rise to a reduction of the concentration of cholesterol and bile acids in bile of the intact rats and of cholesterol in bile of the cholesterol-fed animals.  相似文献   
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Molecular weight and concentration characteristics of immune complexes (IC) from 19 sera of patients with systemic lupus erythematosus (SLE) and CNS impairment have been obtained by the rapid nephelometry assay. Basing on cranial CT findings, the examinees were divided into 2 groups. Group I included patients with cerebral cysts and local dilation of subarachonid spaces, group II those with the above dilatation or that of ventricles of the brain. Small-size IC were registered in 14 sera, their relative molecular mass being under the values derived for donors and SLE patients without CNS affections whereas their level exceeded such in donor sera. Larger IC relative concentrations were seen in group I patients than in group II ones (34 +/- 13 and 18.7 +/- 12, respectively). Five patients failed to demonstrate IC. The presence of small-size IC in high concentrations may be considered a marker of CNS involvement in SLE, the highest concentrations suggesting local impairment of the brain.  相似文献   
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Among mutations associated with autosomal dominant and sporadic Parkinson's disease (PD) the G2019S substitution in the leucine-rich repeat kinase 2 (LRRK2) gene is the most frequently identified. To estimate its frequency in Russia, we analyzed 208 patients with PD from the Northwestern region of Russia. Of these, 51 patients were probands from families with PD compatible with autosomal dominant inheritance. The control group represented 161 subjects without neurological disorders settled in the same region. The frequency of the G2019S mutation was greater in familial PD (2 [3.9%] of 51) than in sporadic PD (1 [0.6%] of 157). In addition, this mutation was found in the proband's father, who also had PD, in 1 PD family, and in 1 carrier without signs of PD at age 40 in another PD family. All carriers were heterozygous for the G2019S mutation and reported the Ashkenazi Jewish origin. The mutation was not found in the control group.  相似文献   
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