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121.
Ileal ulcers and thiobarbituric acid (TBA)-reactive substances in the ileal mucosa were induced in rats treated with a nonsteroidal antiinflammatory drug, 5-bromo-2-(4-fluorophenyl)-3-(4-methylsulfonylphenyl)thiophene (BFMeT), at a dose of 1,000 mg/kg administered with tap water as drinking water. However, the formation of ileal ulcers and TBA-reactive substances in the ileal mucosa was repressed by giving the animals a culture supernatant of Lactobacillus acidophilus as drinking water. We measured the antioxidative activity of the culture supernatant and found that the supernatant inhibited the formation of t-butyl hydroperoxide-induced TBA-reactive substances in erythrocyte membrane ghosts. Therefore, the effects of various known antioxidative compounds on the ileal ulcer formation induced by BFMeT were investigated. While α-tocopherol, t-butyl-1,4-hydroxyanisole and allopurinol did not repress ulcer formation after BFMeT treatment, ascorbic acid, dimethyl sulfoxide, glutathione and β-carotene significantly inhibited formation. Among these compounds, ascorbic acid was the most effective. Accumulation of TBA-reactive substances in the ileal mucosa after BFMeT treatment also decreased significantly in rats treated with ascorbic acid. In addition, the percentage of Gram-negative rods in the ileal contents of rats treated with BFMeT and tap water was dramatically increased, but it was not increased in rats treated with BFMeT and these antioxidants. A positive correlation between the percentage of Gram-negative rods and the number of ileal ulcers was also observed. These results suggest that lipid peroxidation mediated by oxygen radicals plays an important role in the induction of ileal ulcers by BFMeT in rats, and that lipopolysaccharide-activated neutrophils probably produce highly reactive hypochlorous acid and hydrogen peroxide, which are inactivated by ascorbic acid and glutathione, respectively.  相似文献   
122.
Simple sequence repeat (SSR) markers were developed and characterized for Neolitsea sericea (Bl.) Koidz. (Lauraceae). Out of 196 designed primer pairs, a total of 144 pairs showed amplification, of which 44 had clear and stable chromatograms. Polymorphism of these 44 loci was tested using 32 individuals sampled from a single population of N. sericea. The number of alleles and the polymorphism information content varied from 3 to 12 and 0.271 to 0.853, respectively. A significant departure from the Hardy‐Weinberg equilibrium was observed in one of the 44 loci. These SSR markers are useful for population genetic studies and parentage analysis in N. sericea, which is one of the most common evergreen species in coastal Pinus thunbergii forests in central‐western Japan.  相似文献   
123.
The serum total T3 level, evaluated in 687 patients with thyrotoxicosis diagnosed by an elevated serum free T4 level and suppressed serum TSH level, was found to be high in 98.1% and normal in 1.9% of 592 patients with Graves' hyperthyroidism, and high in 75.8%, normal in 21.1% and low in 3.2% of 95 patients with destructive thyroiditis. Non-thyroidal illness was found in about a third of the patients with thyrotoxicosis and a normal serum total T3 level. The serum total T3 level was low with elevated serum thyroglobulin and reverse T3 levels in three patients with severe non-thyroidal illness, in whom the thyroidal radioactive iodine uptake was suppressed and the thyrotoxicosis resolved spontaneously with a normalization of the serum total T3 level after recovery from the destructive thyroiditis and non-thyroidal illness. It is therefore concluded that thyrotoxicosis with a low serum total T3 level, partially due to associated non-thyroidal illness, is more frequently found in patients with destructive thyroiditis than in those with Graves' hyperthyroidism.  相似文献   
124.
α-Ionone, α-methylionone, and α-isomethylionone were converted by Aspergillus niger JTS 191. The individual bioconversion products from α-ionone were isolated and identified by spectrometry and organic synthesis. The major products were cis-3-hydroxy-α-ionone, trans-3-hydroxy-α-ionone, and 3-oxo-α-ionone. 2,3-Dehydro-α-ionone, 3,4-dehydro-β-ionone, and 1-(6,6-dimethyl-2-methylene-3-cyclohexenyl)-buten-3-one were also identified. Analogous bioconversion products from α-methylionone and α-isomethylionone were also identified. From results of gas-liquid chromatographic analysis during the fermentation, we propose a metabolic pathway for α-ionones and elucidation of stereochemical features of the bioconversion.  相似文献   
125.
Relationships among genes and gene products of bacteriophage BF23   总被引:2,自引:1,他引:1       下载免费PDF全文
Twenty-five gene products of bacteriophage BF23 were identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and their functions were studied in relation to type I and II genes classified by means of genetic complementation tests. All the type I mutants were defective in the synthesis of a tail protein, L3. In addition, 4 type I gene products, L5 (gp21), L7 (gp20), L8 (gp29), and L9 (gp25), were identified as constituents of tails (gp21 denotes that a protein is a product of gene 21). Three type IIb mutants in genes 10, 14, and 19 diminished substantially the production of late proteins, including tail and head proteins, and the two other type IIb mutants in genes 1 and 2 were defective in the synthesis of both early and late proteins. Of 14 type IIa mutants, at least 6 were defective in phage DNA synthesis and 2 were defective in the synthesis of head proteins. The defect in the head donor activities of type IIa mutants in extract complementation tests was due to the failure of the formation of mature heads containing DNA. The above results support directly the results of the genetic characterization of BF23 genes.  相似文献   
126.
Acidic non-protein amino acids and peptides in five species belonging to the family Liliaceae —Smilax china, Lilium maximowiczii, Tulipa gesneriana, Allium cepa and A. sativum— were surveyed. Two new amino acids —4-hydroxymethyl- and 4-ethyl-4-hydroxyglutamic acid— were isolated from bulbs of T. gesneriana. The first unequivocal identification of 4-ethylglutamic acid was performed from the same plant tissue. A new dipeptide —S-(2-carboxy-n-propyl)cysteinyl glycine— was isolated from A. cepa. Besides the compounds described above, 4-methylene-, 4-methyl- and 4-hydroxy-4-methylglutamic acid were isolated from S. china, L. maximowiczii, and T. gesneriana, but 4-ethylideneglutamic acid was isolated only from T. gesneriana. 4-Methyleneglutamic acid showed no appreciable biological activity, although this aminoacid has an α,β-unsaturated carboxyl group and reacts easily with cysteine in vitro. The most abundant free amino acid in the plant tissues examined in this study is arginine; nevertheless, acidic Nα-acylarginine derivatives which have been found in S. china and L. maximowiczii and published elsewhere could not be detected in bulbs of T. gesneriana, A. cepa, and A. sativum.  相似文献   
127.
128.
Successful trials were made to estimate the dietary daily intake of lead (Pb) and cadmium (Cd) via foods from the levels of the metals in blood or urine. In practice, 14 and 15 reports were available for Pb and Cd in blood (Pb-B and Cd-B), urine (Pb-U and Cd-U) and 24-h diet duplicates (Pb-D and Cd-D), respectively, from which 68 pairs each of Pb or Cd in blood and food duplicates [each being geometric mean (GM) values for the survey sites] were obtained. Regression analysis revealed that there was a significant correlation between Pb-B and Pb-D, and also between Cd-B and Cd-D, suggesting that it should be possible to estimate both Pb-D and Cd-D from Pb-B and Cd-B, respectively. For Cd-U, the number of available cases was limited (20 pairs), but a significant correlation was detected between Cd-U (as Cd-Ucr, or Cd levels in urine as corrected for creatinine concentration) and Cd-D. Care should be taken in estimating Pb-D from Pb-B, as the ratio of Pb-D over Pb-B may decrease as a function of increasing Pb-B levels. The Pb-D (μg/day) for typical Japanese women with Pb-B of 15 μg/l was best estimated to be 13.5 μg/day. No Cd-B- or Cd-Ucr-dependent change was detected in case of Cd. The best estimate of Cd-D for Cd-B at 1.5 μg/l should be about 19.4 μg/day.  相似文献   
129.
Mutagenic nitroaromatic compounds have recently been found in photocopies, urban atmosphere, automobile exhaust and wastewater. 1-Nitropyrene (1-NP) is readily formed when pyrene, ubiquitous in the environment, is exposed to nitrogen dioxide in the urban atmosphere or in automobile exhaust, and is highly mutagenic, inducing 449 his+ revertants/plate/nmol from Salmonella typhimurium strain TA98 in the absence of S9 fraction in the Salmonella-microsome test. It is possible to swallow sputum or some food containing 1-NP and it would come into contact with the normal bacterial flora. We determined the 1-NP nitroreductase activity in environmental and laboratory bacterial strains. We found that the mutagenicity of 1-NP mixed with the feces of a healthy man or a culture of anaerobic bacteria was decreased. The product proved to be 1-aminopyrene (1-AP), based on its fluorescence spectrum, its mass spectrum, and its characteristic thin layer chromatographic and high performance liquid chromatographic patterns. The 1-NP nitroreductase activity of aerobic bacteria was low, but crude extracts from the anaerobic bacteria, i.e., Bacteroides fragilis, B. thetaiotaomicron, B. vulgatus, Fusobacterium mortiferum, F. nucleatum, Clostridium perfringens, C. sporogenes, Bifidobacterium adolescentis, B. bifidum, Eubacterium lentum, E. limosum, and Peptostreptococcus anaerobius, all easily converted 1-NP to 1-AP and proportionally decreased the mutagenic activity of 1-NP.  相似文献   
130.
MethodsGenetic diversity and structure were examined using 20 microsatellite markers in 37 populations of C. japonica. The locations of glacial refugia were assessed using STRUCTURE analysis, and potential habitats under current and past climate conditions were predicted using SDM. The process of genetic divergence was also examined using the approximate Bayesian computation procedure (ABC) in DIY ABC to test the divergence time between the gene pools detected by the STRUCTURE analysis.ConclusionsThe combined evidence from microsatellites and SDM clearly indicates that climatic changes have shaped the genetic structure of C. japonica. The gene pool detected in northern Tohoku district is likely to have been established by cryptic northern refugia on the coast of the Japan Sea to the west of the Archipelago. The gene pool in Yakushima Island can probably be explained simply by long-term isolation from the other gene pools since the LGM. These results are supported by those of SDM and the predicted divergence time determined using ABC analysis.  相似文献   
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