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排序方式: 共有939条查询结果,搜索用时 203 毫秒
931.
932.
Alex L. Sumich Toshiko Matsudaira Bryony Heasman Rachel V. Gow Almira Ibrahimovic Kebreab Ghebremeskel Michael A. Crawford Eric Taylor 《Prostaglandins, leukotrienes, and essential fatty acids》2013,88(6):431-436
Atypical fatty acid metabolism has been reported in attention deficit hyperactivity disorder (ADHD), however, its relationship with temperament in this population is unclear. The current study investigated the association between blood levels of fatty acids implicated in brain structure and function (omega-3, omega-6, omega-9) and personality traits of stability (neuroticism, conscientiousness and agreeableness) and plasticity (extraversion and openness). Twenty right-handed adolescent boys with ADHD completed a self-report NEO-FFI personality questionnaire, and had fatty acid content assessed from red blood using gas chromatography. Pearson's correlations showed no significant associations between omega-3 levels and personality. After correction for multiple comparisons, Adrenic Acid (C22:4n6) was inversely associated with stability. Oleic acid (C18:1n9) was positively associated with plasticity. Results are in line with a role of fatty acids in brain function. They suggest that those fatty acids that are involved in myelination (Adrenic, Oleic) have the strongest associations with temperament in adolescents with ADHD. 相似文献
933.
G.B. Manjunath S.P. Awasthi M.S.H. Zahid N. Hatanaka A. Hinenoya E. Iwaoka S. Aoki T. Ramamurthy S. Yamasaki 《Letters in applied microbiology》2022,74(4):472-481
Emergence and rapid spread of multidrug-resistant (MDR) bacteria including Vibrio cholerae are a global public health issue. Much attention has been paid to natural compounds, such as spices and herbs to find novel antimicrobial compounds as they are considered to be cheaper alternatives to develop as a drug. Here, we show that methanol extract of white pepper could inhibit the growth of V. cholerae O1 El Tor variant, responsible for the recent outbreaks/epidemics. Furthermore, we demonstrate for the first time that piperine, the major component of white pepper, showed a dose-dependent bactericidal effect on V. cholerae growth irrespective of their biotypes and serogroups in the presence of 200 and 300 µg ml−1 of piperine, respectively. Piperine also inhibited the growth of MDR strains of Pseudomonas aeruginosa, Escherichia coli isolated from poultry and enterohemorrhagic/enteroaggregative E. coli O104 in the presence of 200 µg ml−1. Interestingly, we did not observe any significant inhibitory effect of piperine on E. coli strains isolated from healthy person even up to 200 µg ml−1. Our data suggest that piperine could be a novel antimicrobial agent in therapeutic and preventive applications against infections caused by pathogenic bacteria including MDR strains. 相似文献
934.
M. P. Uitendaal C. H. M. M. De Bruyn M. Hatanaka P. Hösli 《In vitro cellular & developmental biology. Plant》1979,15(2):103-108
Summary A sensitive ultramicrochemical enzyme test for mycoplasmal contamination of cultured cells, based on the determination of
the activity of adenosine phosphorylase, is described. The test was performed by assaying the enzymatic conversion of [8-14C]adenine and ribose-1-phosphate to [8-14C]adenosine by incubating a plastic leaflet carrying a counted number of cells (1 to 10). These leaflets were isolated from
the bottom of the same plastic film dish in which the cells were cultured for experimental or diagnostic purposes, e.g. prenatal
diagnosis or inborn errors of metabolism. The present test should be several 1000-fold more sensitive than the originally
reported enzymatic method because (a) the adenosinephosphorylase reaction is measured in the nucleoside forming direction
which is by far the most active; and (b) the assay is performed with the cells and not with the culture medium. The latter
is of special importance for the detection of those low-grade contaminations in which most of the mycoplasma particles are
attached to cell membranes.
This investigation was partly supported by FUNGO (The Netherlands), INSERM (France) (A. T. P. 36.76.68), and DGRST (France)
(No. 75.50.004). 相似文献
935.
Involvement of GTP-regulatory protein in brain prostaglandin E2 receptor and separation of the two components 总被引:1,自引:0,他引:1
N Yumoto M Hatanaka Y Watanabe O Hayaishi 《Biochemical and biophysical research communications》1986,135(1):282-289
The specific binding protein for prostaglandin (PG) E2 solubilized from porcine brain was sensitive to guanine nucleotides. GTP inhibited the association and enhanced the dissociation of the specific [3H]PGE2 binding. Scatchard analyses showed that GTP (10 microM) decreased the binding affinity more than 3-fold without major change in the number of binding site. Gel filtration separated the binding site from GTP-regulatory component (N). The separated binding protein had a reduced affinity to PGE2 and lost its sensitivity to GTP. The addition of the separated N restored its responsiveness to GTP, and also increased the binding affinity to the original level. These results provide direct evidence for the molecular interaction between the PGE2 binding protein and N in the brain. 相似文献
936.
937.
Shunji Takahashi Wai-Cheung Yip Toshiko Matsugami Goro Tamura 《Journal of plant research》1996,109(4):363-368
The ferredoxin-sulfite reductase (Fd-SiR; hydrogen-sulfide: ferredoxin oxidoreductase, EC 1.8.7.1) activities of shoot and
root of leek (Allium tuberosum) were increased by sulfate limitation in the early stage of growth. Western blot analysis demonstrated an increased amount
of SiRs in root under sulfate limitation, suggesting that SiRs were derepressed. The derepression was observed in shoot when
1.5 mM nitrate was supplied to the plants under sulfate limitation, and clearly in root when 15 mM nitrate was supplied under
sulfate limitation. When nitrate was absent from the nutrient solution, the SiR activity in both tissues was very low. Combined
with the results of the sulfate- or nitrate-limitation experiments, it is suggested that the degree of the derepression of
SiR in both tissue under sulfate limitation is affected by the concentration of nitrate, and further that the mechanism of
regulation of the SiR activity is different in each tissue. The decreases in the ratios of the total SiR activities (shoot/root)
in the latter stage of seedling growth indicate that root play a very important role in sulfate assimilation. 相似文献
938.
A pair of diastereoisomers of Nδ-benzoyl-γ-hydroxy-l-ornithine was synthesized. By comparison with the two synthetic compounds, the natural 相似文献
939.
Assignment of the human calpastatin gene (CAST) to chromosome 5 at region q14----q22 总被引:2,自引:0,他引:2
J Inazawa H Nakagawa S Misawa T Abe S Minoshima R Fukuyama M Maki T Murachi M Hatanaka N Shimizu 《Cytogenetics and cell genetics》1990,54(3-4):156-158
The human calpastatin gene (CAST) was assigned to chromosome 5 by spot-blot hybridization analysis with flow-sorted chromosomes, and it was further sublocalized to bands 5q14----q22 using in situ hybridization to metaphase chromosomes. 相似文献