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31.
Both nitrogen fixation and acetylene reduction by intact cellsof Anabaena cylindrica were inhibited by oxygen, but nitrogenfixation was invariably less sensitive than acetylene reduction.The C2H2/N2 ratio ranged from 6 to 8 in the absence of oxygen,and it decreased with increase in partial pressure of oxygento 2 at a pO2 of 0.3 atm. (Received June 5, 1979; ) 相似文献
32.
Hideki Fukuda Yuji Turugida Takahiro Nakajima Eiji Nomura Akihiko Kondo 《Biotechnology letters》1996,18(8):951-956
Summary Production of phospholipase D (PLD) by Streptoverticillium cinnamoneum immobilized within porous particles was investigated in repeated batch fermentation. The enzyme productivity in repeated batch fermentation was 2.2-fold that obtained in batch fermentation without immobilization, since many of the immobilized cells could be utilized as seed cells for each subsequent batch cycle. 相似文献
33.
Toshihiro Aoki Ikumi Hyohdoh Noriyuki Furuichi Sawako Ozawa Fumio Watanabe Masayuki Matsushita Masahiro Sakaitani Kazutomo Ori Kenji Takanashi Naoki Harada Yasushi Tomii Mitsuyasu Tabo Kiyoshi Yoshinari Yuko Aoki Nobuo Shimma Hitoshi Iikura 《Bioorganic & medicinal chemistry letters》2013,23(23):6223-6227
Introducing a sulfamide moiety to our coumarin derivatives afforded enhanced Raf/MEK inhibitory activity concomitantly with an acceptable PK profile. Novel sulfamide 17 showed potent HCT116 cell growth inhibition (IC50 = 8 nM) and good PK profile (bioavailability of 51% in mouse), resulting in high in vivo antitumor efficacy in the HCT116 xenograft (ED50 = 4.8 mg/kg). We confirmed the sulfamide moiety showed no negative impact on tests run on the compound to evaluate DMPK (PK profiles in three animal species, CYP inhibition and CYP induction) and the safety profile (hERG and AMES tests). Sulfamide 17 had favorable properties that warranted further preclinical assessment 相似文献
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A new polymorphism in the HLA-F gene (67Ala[GCC] to Ala[GCG]) 总被引:1,自引:0,他引:1
S. Kunishima Mineko Nagae Shinichi Mizuno Tadashi Kamiya Kazuo Ozawa 《Immunogenetics》1999,49(2):147-148
37.
Understanding the genetic architecture of complex traits requires identification of the underlying genes and characterization of gene-by-gene and genotype-by-environment interactions. Behaviors that mediate interactions between organisms and their environment are complex traits expected to be especially sensitive to environmental conditions. Previous studies on the olfactory avoidance response of Drosophila melanogaster showed that the genetic architecture of this model behavior depends on epistatic networks of pleiotropic genes. We performed a screen of 1339 co-isogenic p[GT1]-element insertion lines to identify novel genes that contribute to odor-guided behavior and identified 55 candidate genes with known p[GT1]-element insertion sites. Characterization of the expression profiles of 10 p[GT1]-element insertion lines showed that the effects of the transposon insertions are often dependent on developmental stage and that hypomorphic mutations in developmental genes can elicit profound adult behavioral deficits. We assessed epistasis among these genes by constructing all possible double heterozygotes and measuring avoidance responses under two stimulus conditions. We observed enhancer and suppressor effects among subsets of these P-element-tagged genes, and surprisingly, epistatic interactions shifted with changes in the concentration of the olfactory stimulus. Our results show that the manifestation of epistatic networks dynamically changes with alterations in the environment. 相似文献
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Oikawa H Tun Z Young DR Ozawa H Yamazaki K Tanaka E Honda K 《Biochemical and biophysical research communications》2002,297(2):341-345
Hypervariable segments of mitochondrial DNA (mtDNA) (HV1 and HV2) were analyzed in Klinefelter's syndrome and compared to normal population data. One pair of samples consisting of a Japanese mother and affected son with Klinefelter's syndrome (involved in a criminal case), and seven unrelated DNA samples from Caucasian Klinefelter males (two involved in criminal cases and five diagnosed) were collected in Japan and the United States. The diagnosis of Klinefelter's syndrome was established previously by multiplex XY-STR typing detecting two X alleles and one Y allele in the samples. Haplotype analysis of the mtDNA sequence in Klinefelter males was found to be identical, unique, and specific, as it was not found in the normal population. Astonishingly, family data exhibited that the haplotype of the mtDNA in the son was apparently different from the mother's, suggesting that the mtDNA of Klinefelter male would not be inherited from mother to son. Our data indicate that possible interaction of the sex chromosome and the mtDNA exists, and suggests that the specific mtDNA haplotype could cause the abnormal cell to fertilize and reproduce itself. 相似文献
40.
Shimoda K Kamesaki K Numata A Aoki K Matsuda T Oritani K Tamiya S Kato K Takase K Imamura R Yamamoto T Miyamoto T Nagafuji K Gondo H Nagafuchi S Nakayama K Harada M 《Journal of immunology (Baltimore, Md. : 1950)》2002,169(9):4707-4711
IFN-alpha inhibits B lymphocyte development, and the nuclear protein Daxx has been reported to be essential for this biological activity. We show in this study that IFN-alpha inhibits the clonal proliferation of B lymphocyte progenitors in response to IL-7 in wild-type, but not in tyk2-deficient, mice. In addition, the IFN-alpha-induced up-regulation and nuclear translocation of Daxx are completely abrogated in the absence of tyk2. Therefore, tyk2 is directly involved in IFN-alpha signaling for the induction and translocation of Daxx, which may result in B lymphocyte growth arrest and/or apoptosis. 相似文献