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排序方式: 共有1075条查询结果,搜索用时 15 毫秒
1.
High resolution nuclear magnetic resonance study of base pairing in four purified transfer RNA molecules 总被引:3,自引:0,他引:3
The high resolution nuclear magnetic resonance spectra of hydrogen bonded protons in four purified tRNA molecules are reported. From the temperature and concentration dependence it is shown that these resonances arise from intramolecular hydrogen bonds. 相似文献
2.
Norihide Hinomoto Tomomi Higaki Junichiro Abe Masafumi Yamane Eizi Yano 《Applied Entomology and Zoology》2012,47(2):165-171
We have developed and characterized 21 microsatellite markers in the aphidophagous gall midge Aphidoletes aphidimyza (Rondani) (Diptera: Cecidomyiidae). All 21 loci tested were polymorphic: the number of alleles ranged from 2 to 17. Allelic
richness and observed heterozygosities were higher in females than in males. Several loci had no heterozygosity in males,
suggesting that the loci were located on sex chromosomes or E-chromosomes, common to cecidomyiids. The high polymorphism detected
in this study suggests the markers will be of value in analyzing genetic structure of field populations. 相似文献
3.
T. Sasaki M. Yamasaki B. Maruo Y. Yoneda K. Yamane A. Takatsuki G. Tamura 《Biochemical and biophysical research communications》1976,70(1):125-131
Several tunicamycin resistant mutants were obtained from NA64. One of them, B7 strain produced a 5-fold larger amount of α-amylase than NA64 did. Only the amount of α-amylase, among excreted proteins, was enhanced. Genetic analyses by transformation suggested that a single mutation in B7 induced both resistance to tunicamycin and hyperproductivity of extracellular α-amylase. 相似文献
4.
R Maske S Yamane P O Bishop 《Proceedings of the Royal Society of London. Series B, Containing papers of a Biological character. Royal Society (Great Britain)》1986,229(1256):227-256
New knowledge concerning the internal structure and response properties of the receptive fields of striate cells calls for a fresh appraisal of their binocular interactions in the interest of a better understanding of the neural mechanisms underlying binocular depth discrimination. Binocular position-disparity response profiles were recorded from 71 simple and B-cells in response to moving light and dark bars. Predominantly excitatory (PE) cells (N = 48) had disparity response profiles that were spatially closely similar to their respective monocular responses. In addition, the centrally located excitatory subregions were flanked on one or both sides by non-specific inhibitory regions. PE cells with a preferred stimulus orientation within 30 degrees of the vertical (N = 17) showed binocular facilitations with maximal values that were always more than twice (mean 3.3) the sum of the two monocular responses to the same stimuli and generally greater than the facilitations shown by cells with orientations more than 30 degrees from the vertical (N = 29; mean 2.2 times the sum of the respective monocular responses). The strength of the binocular facilitation depended on the stimulus contrast, the facilitation decreasing with increasing contrast. The receptive-field disparity distribution of the 31 PE cells capable of making significant horizontal disparity discriminations has standard deviations of 0.37 degrees and 0.40 degrees, respectively. Predominantly inhibitory cells (PI) (N = 23) showed two basic types of disparity response profile: symmetric (N = 17) and asymmetric (N = 6). Uncertainty regarding the precise location of the binocular fixation point in the anaesthetized and paralysed preparation made it difficult to categorize PI cells adequately. 相似文献
5.
Characterization of the Replication, Maintenance, and Transfer Features of the IncP-7 Plasmid pCAR1, Which Carries Genes Involved in Carbazole and Dioxin Degradation 总被引:4,自引:0,他引:4 下载免费PDF全文
Masaki Shintani Hirokazu Yano Hiroshi Habe Toshio Omori Hisakazu Yamane Masataka Tsuda Hideaki Nojiri 《Applied microbiology》2006,72(5):3206-3216
Isolated from Pseudomonas resinovorans CA10, pCAR1 is a 199-kb plasmid that carries genes involved in the degradation of carbazole and dioxin. The nucleotide sequence of pCAR1 has been determined previously. In this study, we characterized pCAR1 in terms of its replication, maintenance, and conjugation. By constructing miniplasmids of pCAR1 and testing their establishment in Pseudomonas putida DS1, we show that pCAR1 replication is due to the repA gene and its upstream DNA region. The repA gene and putative oriV region could be separated in P. putida DS1, and the oriV region was determined to be located within the 345-bp region between the repA and parW genes. Incompatibility testing using the minireplicon of pCAR1 and IncP plasmids indicated that pCAR1 belongs to the IncP-7 group. Monitoring of the maintenance properties of serial miniplasmids in nonselective medium, and mutation and complementation analyses of the parWABC genes, showed that the stability of pCAR1 is attributable to the products of the parWAB genes. In mating assays, the transfer of pCAR1 from CA10 was detected in a CA10 derivative that was cured of pCAR1 (CA10dm4) and in P. putida KT2440 at frequencies of 3 × 10−1 and 3 × 10−3 per donor strain, respectively. This is the first report of the characterization of this completely sequenced IncP-7 plasmid. 相似文献
6.
OsWRKY28, a PAMP-responsive transrepressor, negatively regulates innate immune responses in rice against rice blast fungus 总被引:1,自引:0,他引:1
7.
Sho Matsui Takumi Yamane Kazuo Kobayashi-Hattori 《Bioscience, biotechnology, and biochemistry》2013,77(5):787-790
Transforming growth factor (TGF) β1-induced plasminogen activator inhibitor (PAI)-1 is one of factors associated with the development of hepatic fibrosis. Calcitonin gene-related peptide (CGRP) shows hepatoprotective effect during hepatic injuries, including fibrosis. However, the effects of CGRP on PAI-1 expression induced by TGFβ1 are unknown. In this study, we investigated the effect of CGRP on TGFβ1-induced PAI-1 expression and its regulatory mechanisms in HepG2 cells. CGRP inhibited TGFβ1-induced PAI-1 expression. H89, a protein kinase A inhibitor, abolished the inhibition of TGFβ1-induced PAI-1 expression by CGRP. TGFβ1 activated mitogen-activated protein kinase (MAPK), including extracellular signal-regulated kinase, c-jun NH2-terminal kinase, and p38, and this activation was abolished by CGRP. These results show that the CGRP-induced cAMP/PKA activation suppresses activation of MAPK induced by TGFβ1, leading to decreased PAI-1 expression in HepG2 cells. 相似文献
8.
Kohei Oda Takanori Imanishi Yoshito Yamane Yoshie Ueno Yoshiharu Mori 《Bioscience, biotechnology, and biochemistry》2013,77(5):882-890
Addition of γ-aminobutyric acid (GABA) and angiotensin converting enzyme (ACE)-inhibitory peptides to the pickles was studied in order to develop a new type of pickles that reduce blood pressure. Based on the outcome of these studies, a new type of fermentation bed composed of rice bran and white miso has been successfully developed. The advantage of such pickles is that they not only contain both GABA and ACE-inhibitory peptides, but also that their taste and flavor are excellent, with colors close to the original ones. The new type of pickles could temporarily reduce blood pressure in two types of rats, spontaneously hypertensive rats and NaCl-sensitive model rats. Thus, the newly developed pickles appear to be beneficial for pickle business. 相似文献
9.
Hajime Yoshida Keizo Hanada Hisakazu Ohsawa Hidehiko Kumagai Hideaki Yamada 《Bioscience, biotechnology, and biochemistry》2013,77(4):1035-1042
Biosynthetic threonine deaminase was purified to an apparent homogeneous state from the cell extract of Proteus morganii, with an overall yield of 7.5%. The enzyme had a s020,w of 10.0 S, and the molecular weight was calculated to be approximately, 228,000. The molecular weight of a subunit of the enzyme was estimated to be 58,000 by sodium dodecyl sulfate gel electrophoresis. The enzyme seemed to have a tetrameric structure consisting of identical subunits. The enzyme had a marked yellow color with an absorption maximum at 415 nm and contained 2 mol of pyridoxal 5′-phosphate per mol. The threonine deaminase catalyzed the deamination of l-threonine, l-serine, l-cysteine and β-chloro-l-alanine. Km values for l-threonine and l-serine were 3.2 and 7.1 mm, respectively. The enzyme was not activated by AMP, ADP and ATP, but was inhibited by l-isoleucine. The Ki for l-isoleucine was 1.17 mm, and the inhibition was not recovered by l-valine. Treatment with mercuric chloride effectively protected the enzyme from inhibition by l-isoleucine. 相似文献
10.
Yukiko Kawanabe Hisakazu Yamane Nobutaka Takahashi Teruko Nakamura 《Bioscience, biotechnology, and biochemistry》2013,77(8):2447-2450
GA3 was identified as a major GA in Neurospora crassa by gas chromatography/selected ion monitoring (GC/SIM) and its content was measured at various stages (0~96 hr after inoculation) of conidial germination and mycelial growth. The GA3 content in the fungus was 190ng/g dry weight at the initial stage and then decreased rapidly; that per liter culture decreased soon after the inoculation, and then increased to 17.6 ng 96 hr after inoculation. The GA3 concentration in the culture medium was around 10?11 m throughout the 96-hr incubation. The physiological role of endogenous GA in Neurospora crassa is also discussed. 相似文献