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101.
We report atomic-scale characterization of the pseudogap state in a high-Tc superconductor, Bi2Sr2CaCu2O(8+delta). The electronic states at low energies within the pseudogap exhibit spatial modulations having an energy-independent incommensurate periodicity. These patterns, which are oriented along the copper-oxygen bond directions, appear to be a consequence of an electronic ordering phenomenon, the observation of which correlates with the pseudogap in the density of electronic states. Our results provide a stringent test for various ordering scenarios in the cuprates, which have been central in the debate on the nature of the pseudogap and the complex electronic phase diagram of these compounds. 相似文献
102.
Iida Y Oh KB Saito M Matsuoka H Kurata H Natsume M Abe H 《Journal of agricultural and food chemistry》1999,47(2):584-587
Antifungal activity was detected from Anemarrhena asphodeloides by the Bio-Cell Tracer (BCT) method. An active fraction was separated by silica gel column chromatography and reverse-phase HPLC. The molecular weight was determined by GC-MS, and the molecular structure was analyzed by IR, (1)H NMR, and (13)C NMR. The isolated compound was found to be identical to nyasol, (Z)-1, 3-bis(4-hydroxyphenyl)-1,4-pentadiene, which formerly appeared in the literature without any remark on the antifungal activity. This compound showed antimicrobial activity against 38 strains of fungi and five strains of bacteria. The minimum inhibitory concentration (MIC) ranged from 12.5 to 200 microg mL(-)(1), except for two strains based on the broth dilution method. 相似文献
103.
Cystatins are protein inhibitors of cysteine proteinases of the papain family, and those of animal origin have long been studied from medical and physiological aspects. In the meantime, oryzacystatin cloned from rice seeds in 1987 was recognized as the first well-defined cystatin of plant origin. Cloning studies followed to disclose various plant cytstatins including those of corn and soybean origin, their similarities to and differences from animal cystatins being analyzed in detail. Plant seed cystatins are now understood as factors controlling germination by inhibition of endogenous cysteine proteinases. They can also recognize insect midgut proteinases as exogenous target enzymes to control. This paper discusses chemical and phytophysiological relationships between cystatins and their targets. 相似文献
104.
Extractive components were determined for the mantle muscle and liver of three species of Loliginidae squid, Sepioteuthis lessoniana, Loligo bleekeri, and L. edulis, and one species of Ommastrephidae, Todarodes pacificus, as a control. Total free amino acid levels and the major free amino acids in muscle, taurine, proline, glycine, alanine,
and arginine, were significantly higher in Loliginidae squids than in T. pacificus. The main nucleotide was adenosine 5′-monophosphate, which did not differ significantly between species. Malate was the organic
acid found in muscle in highest concentrations. The muscle of these species contained a large amount of trimethylamine oxide.
A large amount of glycine betaine was also detected in the muscle, but showed no large species difference. From these results,
the muscle of Loliginidae species is considered to have a much sweeter taste than that of T. pacificus. Compared with muscle, squid liver was characteristic with high contents of taurine, glutamate, bitter amino acids, succinate,
propionate, trimethylamine, and glycine betaine, and with low contents of sweet amino acids, arginine, nucleotides, malate,
and trimethylamine oxide. These results suggest that squid liver is characterized by a complicated taste containing umami,
bitterness, sourness, fishy flavor, and less sweetness. 相似文献
105.
Takashi Okayama Tooru Ooizumi Yoshiaki Akahane Sei-Ichi Kitakami Yo-Ichi Abe Jun Shirai 《Fisheries Science》2007,73(4):931-939
Changes in physical properties of two-step heated gels on addition of gluconate were investigated in terms of relationships
between breaking strength and gel stiffness. Regression lines between the breaking strength and the gel stiffness were extended
to the x-axis (gel stiffness), and the intercept was defined as SBSO. The SBSO of the two-step heated gels increased with gluconate contents in salt-ground surimis, suggesting that the harder but less elastic gels formed on addition of gluconate were dose-dependent. Conversely, the denaturation
rate constants of myosin in salt-ground surimis during preheating estimated by means of Ca-ATPase inactivation, loss of salt solubility, and decrease of denaturant solubility
were considerably reduced by gluconate. Thus, the progress of myosin denaturation was strongly suppressed. Increments of SBSO (δSBSO) of the two-step heated gels on addition of gluconate were inversely correlated with the denaturation rate constants of myosin
in salt-ground surimis for every index. Thus, the changes in physical parameters of two-step heated gel caused by gluconate may be associated with
the sluggish progress of myosin denaturation in salt-ground surimi during preheating. 相似文献
106.
T Itami M Kondo M Uozu A Suganuma T Abe A Nakagawa N Suzuki Y Takahashi 《Journal of fish diseases》1996,19(2):185-187
107.
Insular ecosystems can be dramatically affected by alien species, and records of pre-eradication status are essential to evaluate
the effects of eradicating alien species. Nishi-jima Island is a small island of the Ogasawara group on which the first program
of complete eradication of alien herbivorous mammals (black rats and feral goats) will be conducted. After eradication, the
government plans to conduct ecosystem restoration on the island. This paper reports the angiosperm flora and vegetation of
Nishi-jima Island before eradication of the rats and goats, with the objective of aiding ecosystem management after the eradication.
Our surveys indicate that vegetation cover by the alien tree, Casuarina equisetifolia has expanded compared with its distribution in a 1974 aerial photograph of the island. The predominant vegetation in 2006
was C. equisetifolia forests and Zoysia tenuifolia grasslands, with fragmented native tree vegetation. The flora of the island comprised 69 angiosperm species (50 indigenous
species) of which 30% were endemic, far less than for the Ogasawara Islands as a whole (45%). However, several populations
of endangered plants remain. To restore the native ecosystem on Nishi-jima, eradication of C. equisetifolia is important in addition to eradication of alien herbivorous mammals. 相似文献
108.
Mitsuhisa Baba Shintaro Abe Makiko Kasai Toshihiro Sugiura Hiroshi Kobayashi 《Journal of Forest Research》2011,16(6):446-455
Understory vegetation may affect nitrate (NO3
−) leaching, even in coniferous forests. Our objective was to estimate the contribution of understory vegetation to nutrient
cycling, especially nitrogen, in a Japanese cedar (Cryptomeria japonica) stand. We therefore cut down and removed understory vegetation in one plot of the stand (the cutting plot) to compare nutrient
budgets in the cutting plot with those in a control plot in which understory vegetation was allowed to grow. We also examined
neutralization of the acid produced due to an increase in NO3
− leaching. A monitoring study on precipitation and soil-percolated water was carried out in both plots. When the understory
vegetation was cut down, NO3
− flux at a soil depth of 10 cm increased remarkably in summer, with values significantly higher than those in the control
plot. This resulted in an increase in proton load associated with N transformation ([H+]load). The increase in [H+]load enhanced mobilization of Ca2+, Mg2+, and SiO2 ([SiO2]mob). In addition, the correlations between [SiO2]mob and mobilization of each base cation were distinct in the cutting plot. These results indicated that the acids produced
because of N transformation were buffered not only by ion exchange but also by chemical weathering. The contribution of understory
vegetation to minimizing NO3
− leaching suggested that understory vegetation might reduce the risk of N saturation because of chronic atmospheric N inputs. 相似文献
109.
Response of plasma bone markers to a single intramuscular administration of calcitriol in dairy cows
Danil Kim Norio Yamagishi Izumi Abe Bhuminand Devkota Norimoto Okura Shuichi Ohashi 《Research in veterinary science》2011,90(1):124-126
To elucidate the effects of an exogenous calcitriol (1,25-dihydroxyvitamin D3) on plasma bone markers, the formation item osteocalcin (OC), undercarboxylated OC (ucOC) and bone-specific alkaline phosphatase (BALP), and the resorption parameter tartrate-resistant acid phosphatase isoform 5b (TRAP5b) and hydroxyproline (HYP) were measured in conjunction with plasma calcitriol and calcium (Ca) concentrations in dairy cows receiving calcitriol or its vehicle according to a 2 × 2 crossover design. Calcitriol (0.5 μg/kg, i.m.) increased significantly its plasma level during 6 h to day 2 and plasma Ca concentration during 12 h to day 7 compared to the vehicle. Also, plasma OC and ucOC started to rise from day 3 and 1, respectively, and remained elevated until day 7. No change in plasma BALP, TRAP5b or HYP associated with calcitriol treatment was noted. These results demonstrate that exogenous calcitriol stimulates osteoblasts to biosynthesise OC, a determinant of the bone formation in cows. 相似文献
110.
To estimate the glomerular filtration rate (GFR) in horses, an optimum dose of the nonionic contrast medium iodixanol as a
tracer was assessed with blood-sample times. Iodixanol was administered intravenously at 10–40 mg I/kg to geldings and mares,
and blood was collected 30, 60, 90, 120, 150, and 180 min later. Serum iodixanol concentration was determined by high-performance
liquid chromatography (HPLC), and serum urea nitrogen (UN) and creatinine concentrations were also measured. The combination
of 20 mg I/kg iodixanol and sampling times of 60, 90, and 120 min after injection was considered to be appropriate for practical
use. In clinically healthy horses, the reference values were determined to be 1.90 ± 0.03 ml/min/kg (150.8 ± 2.94 ml/min/m2), consistent with historical data using different tracers. The result suggests that serum clearance of iodixanol is a ready-to-use
tool for a screening of alterations in the equine GFR, although it is necessary to perform a more longitudinal study using
horses with a variety of renal functions. 相似文献