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21.
Michio Tsukamura 《Journal of bacteriology》1965,90(2):556-557
22.
Summary A much higher incidence of alcohol flushing among Orientals in comparison to Caucasians, i.e., >50% vs 5%–10%, has been attributed to racial differences in alcohol-metabolizing enzymes. A large majority of Orientals are atypical in alcohol dehydrogenase-2 locus (ADH
2
), and their livers exhibit significantly higher ADH activity than the livers of most Caucasians. Approximately 50% of Orientals lack the mitochondrial aldehyde dehydrogenase (ALDH2) activity, and elimination of acetaldehyde might be disturbed. We determined by means of hybridization of genomic DNA samples with allele specific oligonucleotide probes, genotypes of the ADH
2
and ALDH
2
loci in Japanese alcohol flushers and nonflushers. We found that all individuals with homozygous atypical ALDH
2
2
/ALDH
2
2
and most of those with heterozygous atypical ALDH
1
2
/ALDH
2
2
were alcohol flushers, while all subjects with homozygous usual ALDH
1
2
/ALDH
1
2
were nonflushers. Frequency of the atypical ADH
2
2
was found to be higher in alcohol flushers than in nonflushers, but the statistical significance was not established in the sample size examined. 相似文献
23.
Masayoshi Takahashi Hiroshi Yokota Dai Ayusawa Michio Oishi Tetsuo Kunieda 《Biochemical genetics》1992,30(9-10):537-544
A novel restriction fragment length polymorphism (RFLP) in inbred rats was revealed by Southern blot analysis with a clone arbitrarily chosen from a rat genomic library as a probe. A clone named alpha 403 showed interstrain variations in the length of the EcoRI and HindIII fragments. The EcoRI fragments were either 0.7 or 3 kb, those of HindIII were either 4.5 or 5 kb, and three types were identified as combinations of those fragments in 20 inbred rat strains. These types segregated in backcross progeny as codominant alleles. The locus for the RFLP was thus named A403. Analysis of linkage between the RFLP locus and 13 other loci reveal that the A403 locus was closely linked to the Cs-1 locus (15 +/- 5.2%), which belongs to rat linkage group XIII. 相似文献
24.
Hideko Yamamoto-Otake Asahi Matsuyama Eiichi Nakano 《Applied microbiology and biotechnology》1990,33(6):680-682
Summary A phosphotransacetylase gene (pta) has been cloned from a genomic DNA library ofEscherichia coli 1100, a derivative of strain K-12. The phosphotransacetylase activities ofpta
+ plasmid-containing strains were amplified about 150-fold under control of thelac promoter. The molecular weight of the phosphotransacetylase was estimated to be about 81,000 by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. Thepta gene was found to be downstream ofackA by a combination of restriction analysis and plasmid subcloning. It is located about 13 kb upstream of thepurF-folC-hisT region of the chromosome. 相似文献
25.
Pinus species exhibit paternal chloroplast inheritance and maternal mitochondrial inheritance. This independent inheritance of
two cytoplasmic genomes provides an exceptional environment for discriminating female (seeds) and male (pollen) components
of gene flow across hybridizing species. We obtained mitochondrial genetic markers diagnostic toP. parviflora var.pentaphylla andP. pumila by PCR amplification of the intron ofnad1 on mtDNA, and examined the spatial-distribution pattern of the mtDNA haplotypes in a hybrid zone betweenP. parviflora var.pentaphylla andP. pumila in the Tanigawa Mountains of Japan. These data, in conjunction with previous information on cpDNA haplotypes and needle morphology,
revealed contrastive patterns of introgression of two cytoplasmic genomes. CpDNA introgression has occurred uni-directionally
fromP. parviflora var.pentaphylla toP. pumila. Conversely, mtDNA introgression has occurred in the opposite direction, fromP. pumila toP. parviflora var.pentaphylla. Levels of introgression are roughly equivalent for cpDNA and mtDNA. The contrastive spatial distribution pattern of cpDNA
and mtDNA haplotypes could be caused by differential movement of seeds and pollen for interspecific genetic exchange. 相似文献
26.
The in-gel competitive reassociation (IGCR) procedure was successfullyapplied to construct a comprehensive library enriched in DNAfragments containing C5mCGG sequences from mouse liver and braingenomic DNA. For IGCR, methylation-insensitive restriction enzyme(Msp I) digests were used as target DNA and methylation-sensitiverestriction enzyme (Hpa II) digests as competitor DNA. Southernblot analysis indicated that 60 to 70% of the clones in thelibrary were derived from the methylated sites and overall enrichmentwas 200- to 1000-fold. IGCR was further applied to constructa library for the sites differentially methylated between brainand liver DNA. In the library, approximately 20% of the HpaII sites exhibited different degrees of methylation betweenthese tissues. 相似文献
27.
Michio Imafuku 《Journal of Ethology》1994,12(2):107-114
Shell rotating behavior of the hermit crabPagurus geminus was investigated. In preliminary observations, hermit crabs motivated to change shells rotated presented shells, filled with
sand, in a way that dislodged the inside material. In order to determine if this behavior is stereotyped, or flexible and
dependent on shell type, hermit crabs were tested with ordinary dextral shells ofLatirulus nagasakiensis and sinistral shells ofAntiplanes contraria. Sinistral shells are not normally encountered by hermit crabs. Their rotation of the dextral shell to the left was adequate
for sand discharge. Sinistral shells were rotated in both directions. Analysis of recorded videotapes showed that variation
in rotation direction could be attributed to variation in the position of the crab relative to the shell. When the crab faced
the shell aperture from the inner lip, it rotated the sinistral shell to the right, and to opposite direction when it faced
from the outer lip side. The crab always pushed the upper side of the horizontally laid shell, regardless of shell type or
its own position. 相似文献
28.
29.
A procedure for the mass propagation of multiple shoots of Stevia rebaudiana is described. Isolated shoot primordia were used as the inoculum to obtain clusters of shoot primordia. Such clusters were grown in a 500 liter bioreactor to obtain shoots. A total of 64.6 Kg of shoots were propagated from 460 g of the inoculated shoot primordia. These shoots were easily acclimatized in soil. 相似文献
30.
Kimura Tetsuya; Takeda Shin; Kyozuka Junko; Asahi Tadashi; Shimamoto Ko; Nakamura Kenzo 《Plant & cell physiology》1993,34(2):345-355
A precursor to the 相似文献