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191.
192.
Takahashi H Nishina A Fukumoto RH Kimura H Koketsu M Ishihara H 《Life sciences》2005,76(19):2185-2192
Oxygen radicals, such as superoxide radicals, embellishing DNA, protein, lipids, etc., and carrying out the obstacle of the function of a cell is known. It depends for the oxidant level in the living body on the balance of a generation system and an elimination system of oxygen radicals, and research which controls an oxidant level in the living body is briskly done by taking in the substance which eliminates an oxygen radical. We investigated scavenging effects of superoxide radicals by selenoureas and thioureas using a highly sensitive and quantitative chemiluminescence method. At 330 nM, five selenoureas and five thioureas scavenged fractions of superoxide radicals (O2-) ranging from 8.4% to 87.6%. Among five N,N-unsubstituted selenoureas and N,N-unsubstituted thioureas 1-selenocarbamoylpiperidine and 1-thiocarbamoylpyrrolidine were the most effective scavengers. A possibility that selenoureas could use it as a new superoxide anion-scavenging substance from the result of this research became clear. 相似文献
193.
Using the deterministic sampling, patterns of the log-likelihood surfaces expected in some interval mapping procedures for estimating the position of, and the effect for, QTL(s) were investigated for the situations where a single QTL or closely linked QTLs are contained in a chromosome segment bracketed with two markers. The mapping procedures compared were the conventional, likelihood-based interval mapping (IM), the regression interval mapping (RIM), and the QTL-cluster mapping (CM) in which the conditional probabilities of transmission of the whole segment marked by the flanking markers were taken into consideration. The half-sib design was used here, and several cases of the true genetic model were considered, differing in the number of QTLs contained in the marker interval, the linkage phase for the sire, and the magnitude of the QTL(s) effect. For the true genetic models where a single QTL or closely linked QTLs being in coupling phase are contained in the interval, with (R)IM, clear global maxima of the log-likelihood were observed within the range of the marker interval. It was shown that the estimates of the QTL(s) effect at the marked segment level are expected to be unbiased. On the other hand, in a setting where the linkage phase for the linked QTLs located in the interval was different from coupling and repulsion, there was found a ridge along the interval for the log-likelihood surface with (R)IM, indicating the dependency between the estimates of the position of, and the effect for, the putative QTL. For this case, it was found that the position of the putative QTL could be estimated as that of one of the flanking markers, and the estimate of the QTL effect be biased. In contrast, it was revealed that CM is expected to provide the unbiased estimate of the QTL(s)-effect at the segment level for any case of the true genetic models considered here. If the aim is for marker-assisted selection rather than mapping closely linked QTLs individually, then the CM approach is considered to be useful. 相似文献
194.
195.
Rescue of abnormal phenotypes of the delta2 glutamate receptor-null mice by mutant delta2 transgenes
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The delta2 glutamate receptor (GluRdelta2) has a crucial role in cerebellar functions; disruption of GluRdelta2 alleles in mice (delta2(-/-)) impairs synapse formation and long-term depression, which is thought to underlie motor learning in the cerebellum, and consequently leads to motor discoordination. However, it has been unclear whether GluRdelta2 is activated by glutamate analogues. Here we introduced a GluRdelta2 transgene, which had a mutation (Arg514Lys) in the putative ligand-binding motif conserved in all mammalian ionotropic glutamate receptors (iGluRs) and their ancestral bacterial periplasmic amino-acid-binding proteins, into delta2(-/-) mice. Surprisingly, a mutant GluRdelta2 transgene, as well as a wild-type GluRdelta2 transgene, rescued all abnormal phenotypes of delta2(-/-) mice. Therefore, these results indicate that the conserved arginine residue, which is crucial for the binding of iGluRs to glutamate analogues, is not essential for the restoration of GluRdelta2 functions in delta2(-/-) mice. 相似文献
196.
Using four clones isolated from Echinococcus multilocularis cDNA library with alveolar echinococcosis (AE) patient sera, various antigens were expressed as ThioHis tag-fused protein. Recombinant EmII/3 antigen was produced as the five fragments divided into the N-terminal (#5 and #5s), the central (#6 and #6s) and the C-terminal domain (#7). Immunoblot analysis revealed that the #7 showed significant reactivity whereas those of #5 and #5s were relatively low. The #6 and #6s also showed lower reactivity than that of #7, although the two minor bands of #6 reacted with every serum. These results suggested that an immunodominant region of EmII/3 locate within the C-terminal one third. The #8s recombinant antigen, Ser23–Glu176 of actin filament fragmenting protein (AFFP), apparently reacted with the AE patient sera, while the #1 antigen synthesized as a full-length antigen B1 did not show such high reactivity. Thus, #7 and #8s antigens showed significant potential for use in immunodetection of AE. In addition, the specific antibodies against #7 and #8s reacted with specific antigens in crude extract of E. multilocularis cyst, indicating that these antigens retained antigenicity common to native EmII/3 and AFFP, respectively. 相似文献
197.
198.
Mahama CI Koné A de la Rocque S De Deken R Geerts S 《Bulletin of entomological research》2005,95(1):63-67
The classification of a Landsat Thematic Mapper satellite image helped demonstrate prevailing habitat types and land use intensity in the Volta basin of the Northern Region of Ghana. A geo-referenced data layer comprising the capture results of a cross-sectional survey of Glossina tachinoides Westwood was over-laid on a data layer of habitat types within 500 m of either bank of the Volta river and its tributaries. An evaluation of the relationship between habitat types and the capture results of G. tachinoides suggested a strong preference of G. tachinoides for woodland, followed by shrubland, grassland and flood plains. The findings were used to classify the suitability of habitat types for G. tachinoides as 'high', 'medium' and 'low' and a prediction map for the distribution of G. tachinoides in the entire river network was produced. The usefulness of this method in estimating the potential distribution of G. tachinoides in an area of increasing agricultural expansion is discussed. 相似文献
199.
The phosphorylation of the branched cyclodextrins, mono-6-O-(alpha-D-glucopyranosyl)cyclomaltohexaose, mono-6-O-(alpha-D-maltosyl)cyclomaltohexaose, mono-6-O-(alpha-D-glucopyranosyl)cyclomaltoheptaose, and mono-6-O-(alpha-D-maltosyl)cyclomaltoheptaose, in aqueous solution by sodium cyclo-mono-mu-imidotriphosphate (cMITP) was examined. In these reactions, only the 2-OH group of a single alpha-D-glucopyranosyl residue of the cyclodextrin ring was phosphorylated, in a maximum yield of 67%. A possible mechanism for the phosphorylation is discussed. 相似文献
200.
Genomewide high-density SNP linkage analysis of 236 Japanese families supports the existence of schizophrenia susceptibility loci on chromosomes 1p, 14q, and 20p 总被引:2,自引:1,他引:1
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Arinami T Ohtsuki T Ishiguro H Ujike H Tanaka Y Morita Y Mineta M Takeichi M Yamada S Imamura A Ohara K Shibuya H Ohara K Suzuki Y Muratake T Kaneko N Someya T Inada T Yoshikawa T Toyota T Yamada K Kojima T Takahashi S Osamu O Shinkai T Nakamura M Fukuzako H Hashiguchi T Niwa SI Ueno T Tachikawa H Hori T Asada T Nanko S Kunugi H Hashimoto R Ozaki N Iwata N Harano M Arai H Ohnuma T Kusumi I Koyama T Yoneda H Fukumaki Y Shibata H Kaneko S Higuchi H Yasui-Furukori N Numachi Y Itokawa M 《American journal of human genetics》2005,77(6):937-944
The Japanese Schizophrenia Sib-Pair Linkage Group (JSSLG) is a multisite collaborative study group that was organized to create a national resource for affected sib pair (ASP) studies of schizophrenia in Japan. We used a high-density single-nucleotide–polymorphism (SNP) genotyping assay, the Illumina BeadArray linkage mapping panel (version 4) comprising 5,861 SNPs, to perform a genomewide linkage analysis of JSSLG samples comprising 236 Japanese families with 268 nonindependent ASPs with schizophrenia. All subjects were Japanese. Among these families, 122 families comprised the same subjects analyzed with short tandem repeat markers. All the probands and their siblings, with the exception of seven siblings with schizoaffective disorder, had schizophrenia. After excluding SNPs with high linkage disequilibrium, we found significant evidence of linkage of schizophrenia to chromosome 1p21.2-1p13.2 (LOD=3.39) and suggestive evidence of linkage to 14q11.2 (LOD=2.87), 14q11.2-q13.2 (LOD=2.33), and 20p12.1-p11.2 (LOD=2.33). Although linkage to these regions has received little attention, these regions are included in or partially overlap the 10 regions reported by Lewis et al. that passed the two aggregate criteria of a meta-analysis. Results of the present study—which, to our knowledge, is the first genomewide analysis of schizophrenia in ASPs of a single Asian ethnicity that is comparable to the analyses done of ASPs of European descent—indicate the existence of schizophrenia susceptibility loci that are common to different ethnic groups but that likely have different ethnicity-specific effects. 相似文献