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21.
Summary Pseudomonas acidovorans DMR-11, capable of oxidizing dimethyl sulfide (DMS), was isolated from peat biofilter. DMS as a sole carbon or energy source was not degraded, but it was co-degraded in the medium containing organic carbon sources. The removal rate of DMS in heat-treated glucose medium was 1.12×10–17 mole/h cell at 30 °C. Dimethyl sulfoxide (DMSO) was the only product of DMS oxidation and was formed stoichiometrically. DMS was reversibly evolved in excess of DMSO. The cell free extract of strain DMR-11 oxidized DMS in presence of NADPH.  相似文献   
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Mitochondrial DNA polymorphism among five Asian populations   总被引:13,自引:8,他引:5       下载免费PDF全文
Mitochondrial DNA (mtDNA) polymorphisms were detected using 13 restriction enzymes on the total DNA obtained from blood samples of five Asian populations: Japanese and Ainu of northern Japan, Korean, Negrito (Aeta) of the Philippines, and Vedda of Sri Lanka. Of a total of 28 restriction-enzyme morphs detected, eight had not been reported previously. By combining the morphs, we were able to classify mtDNAs of 243 individuals into 20 mtDNA types. Phylogenetic analyses using maximum parsimony and genetic distance methods both showed that the Japanese, Ainu, and Korean populations were closely related to each other. Aeta was found to show a relatively close relationship to these three populations, confirming the conclusion from previous studies of blood markers. In contrast, Vedda was quite different from the other four populations.  相似文献   
25.
The plasma levels of fibronectin (Fn) have been measured in normal subjects and in patients with thyroid diseases. The mean plasma Fn levels in 62 normal adults was 32.0 +/- 6.0 mg/dl, whereas it was elevated to 62.6 +/- 16.1 mg/dl (mean +/- SD) in 25 patients with hyperthyroidism and decreased to 19.2 +/- 8.0 mg/dl in 9 patients with hypothyroidism. The 9 patients with simple goiter have normal values of 29.1 +/- 8.0 mg/dl. With the administration of anti-thyroid drugs, plasma Fn levels normalized, with a time lag, in parallel with normalization of the thyroid function. Positive correlation was obtained between Fn levels and serum levels of triiodothyronine (T3) and thyroxine (T4). The present findings indicate that measurement of plasma Fn both in the basal state and during treatment provides evidence of altered Fn metabolism in thyroid diseases and serves to follow up the effect of treatment.  相似文献   
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K Nakajima  K Ikuta  S Ueda  S Kato    K Hirai 《Journal of virology》1986,59(1):154-158
Two groups of virus-specific polypeptides were identified in the nuclei of infected cells by cross-reacting monoclonal antibodies with three serotypes of Marek's disease virus. Of these, a 135,000-molecular-weight polypeptide common to all three serotypes was found to bind to both double-stranded and single-stranded DNAs.  相似文献   
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The effect of quercetin as the comutagen on 2-acetylaminofluorene (AAF) was investigated. AAF was metabolized with mammalian metabolic systems (S9 mix) in the presence or absence of quercetin in vitro, and its metabolites were determined by high-performance liquid chromatography. In the presence of quercetin, the total metabolic rate of AAF decreased compared with that in the absence of quercetin, whereas the formation of N-hydroxy-AAF (N-OH-AAF) and 2-aminofluorene (AF) increased. Since the main metabolic pathway of AAF is aryl-hydroxylation, it is suggested that the decrease of total metabolic rate of AAF is due to the inhibition of aryl-hydroxylation by quercetin. From these results, it seems probable that the comutagenic effect of quercetin on AAF is due to the inhibition of aryl-hydroxylation (the detoxifying pathway) and the promotion of N-hydroxylation and deacetylation (the activating pathway) in the AAF metabolism with S9 mix.  相似文献   
28.
The localization of the Epstein-Barr virus (EBV) genome in chromosomes of human B-lymphoblastoid cell lines (LCLs) transformed with EBV, and the effect of EBV DNA on the level of sister chromatid exchange (SCE) in Bloom's syndrome (BS) B-LCLs, were examined with chromosomal in situ hybridization techniques using a 3H-EBV DNA probe. EBV DNA was detected in chromosomes 1–5 and 13–15 at specific G band regions in BS as well as in normal B-LCLs, regardless of SCE. Several chromosomal sites (1p31, 1q31, 4q22–24, 5q21, 13q21, 14q21) carrying EBV DNA seemed to be very characteristic in normal as well as in BS B-LCLs. There was no statistically significant difference in silver grain counts due to EBV DNA and their distribution in different chromosomes or groups among normal and BS B-LCLs with normal and high SCE. These findings strongly indicate that EBV infection did not introduce a correcting factor for BS SCE.  相似文献   
29.
Chromoplast DNA was isolated from ripe-red tomato fruits, andits structure compared with that of chloroplast DNAs from maturegreen fruits and leaves. There was a good correspondence betweenthe structures analyzed by BamHI or EcoRI digestion and by hybridizationwith a probe for the gene of the ribulose 1,5-bisphosphate carboxylase/oxygenaselarge subunit. 1 Present address: Koryo International College, Nisshin, Aichi470-01, Japan. (Received November 5, 1984; Accepted February 6, 1985)  相似文献   
30.
We examined C-banded karyotypes of six species of lung flukes from Japan and Korea; diploid and triploid Paragonimus westermani, P. miyazakii, P. ohirai, P. iloktsuenensis and P. sadoensis, with special reference to their karyotypic diversification. C-band analysis between the diploid and the triploid westermani revealed that two of three homologues of the triploid resembled those of the diploid in C-band pattern, while the remaining chromosome showed a different pattern from any species examined here. This karyological evidence indicates that the triploid is allotriploid probably induced by interspecific hybridization between the diploid westermani and an unknown species; we, therefore, suggest that the triploid westermani is an independent species and synonymous with P. pulmonalis (Miyazaki 1978). As the morphologically similar three species, ohirai, iloktsuenensis and sadoensis, had the same C-band polymorphism in chromosome No. 4, these species are classified as the local races of P. ohirai. Paragonimus miyazakii has one common C-band (5q) with the diploid westermani, but other bands (1q, 4q, 6q, 7p and 7q) are different. From these observations, the six species examined are phylogenetically divided into three groups: (1) westermani group containing diploid and triploid (= pulmonalis) species, (2) miyazakii and (3) ohirai including two geographic races, iloktsuenensis and sadoensis.  相似文献   
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