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排序方式: 共有442条查询结果,搜索用时 15 毫秒
431.
Indirect enzyme-linked immunosorbent assays (ELISAs) have been applied to detect immunoglobulin Y antibodies to different serotypes of Salmonella in the yolks of chicken eggs with heat-extracted antigens of Salmonella enterica serotypes Agona (SA), Cerro (SC), Enteritidis (SE), Montevideo (SM), and Putten (SP). The egg yolk samples examined were classified as positive if their ELISA absorbance values exceeded the value for eggs from specific-pathogen-free flocks by more than two standard deviations. Of 30 egg yolk samples from three flocks vaccinated with a killed SE vaccine, 29 were antibody positive by the ELISA assay for the SE antigen. Four to 29 of the 29 yolk samples showed positive results for the other serovars, although the absorbance values for SE were higher than those obtained for the other serotypes in each of the yolk samples. All 30 yolks from three flocks that were not administered any SE vaccines were found to be antibody negative for SE, and two samples were determined to be positive for SC. Thirty-nine or 40 eggs were obtained from each of four layer flocks in a commercial egg production farm where the laying houses were naturally contaminated with SA, SC, SM, SP, Salmonella serovar Infantis (SI), and untypeable strains. The ELISA absorbance values for SM in the egg yolks obtained from the two flocks molted through feed withdrawal when the birds restarted laying were significantly (P < 0.05) higher than those observed in the yolks obtained before the molt. In egg yolks from the two other flocks that were molted through a wheat bran diet, there was no significant difference between the absorbance values before and after the molt. The observations in the present study provide further evidence to suggest that a molt initiated through the administration of a wheat bran diet can reduce the risk for Salmonella problems in a commercial egg-producing setting. 相似文献
432.
Cyanobacterial growth in semi-closed water areas such as reservoirs brings about a coagulation inhibition in a drinking water treatment system, but the inhibitory substances and mechanisms involved have yet to be elucidated. In this study, proteins having a high affinity with polyaluminum chloride (PACl) were isolated from organic substances produced by Microcystis aeruginosa with the affinity chromatography technique. Both extracellular organic matter (EOM) and cellular organic matter (COM) disturbed the flocculation of suspended kaolin with PACl, but it was likely that nonproteinous substances in EOM cause the reduction of coagulation effciency. In contrast, proteins in COM were obtained as possible inhibitory substances for the coagulation with PACl. These proteins could consume PACl in the coagulation process due to the formation of chelate complexes between these inhibitory proteins and the coagulant. The consumption of PACl by cyanobacterial proteins could be one of the important causes of the increase in coagulant demand. 相似文献
433.
Relationship between the solubility of disperse dyes and the equilibrium dye adsorption in supercritical fluid dyeing 总被引:3,自引:0,他引:3
Isao Tabata Jinha Lyu Sungmi Cho Tomoko Tominaga Teruo Hori 《Coloration Technology》2001,117(6):346-351
In order to understand the dyeing behaviour of synthetic fibres in supercritical carbon dioxide, the solubility of some disperse dyes in supercritical fluid, as well as the rate of dyeing and the equilibrium adsorption of these dyes, have been studied. Dye solubility was measured by a dynamic analytic method at a range of pressure (7.5–25 MPa) and temperature (50–145 °C). The apparent rate of dyeing was measured and the dyeing isotherm was obtained by plotting the equilibrium dye adsorption against the equilibrium dyebath concentration. Linear isotherms were obtained when poly(ethylene terephthalate) samples were dyed with the disperse dyes. The mechanism of dyeing using supercritical carbon dioxide was discussed by considering the solubility, the dyeing rate and the dyeing isotherm. 相似文献
434.
Tomonori Nishimoto Tomoko Takagi Michio Kondo Akihisa Matsuda 《Solar Energy Materials & Solar Cells》2001,66(1-4)
We deposited a-Si : H,F films at a high-growth rate (15 Å/s) using a SiH4 and SiF4 gas mixture to examine the effect of halogen additives on the film stability against light exposure. Fluorinated a-Si : H films show a high conductivity over 5×10−5 S/cm and the Schottky cells made with fluorinated films exhibit an improved fill factor after light-soaking. SIMS measurements show an increased oxygen incorporation into the film at a SiF4 flow of 5 sccm or larger, while virtually no increase is seen when a small SiF4 flow rate of 1 sccm is used. This is presumably an indication that a small amount of SiF4 can actually help improve the stability of a-Si : H films against light exposure. 相似文献
435.
Hiromi Yoshida Yuki Hirakawa Yoshiyuki Mizushina Tomoko Tanaka 《European Journal of Lipid Science and Technology》2002,104(6):347-352
Whole sunflower seeds (Helianthus annuus L.) were exposed to microwaves for 6, 12, 20 or 30 min at a frequency of 2450 MHz. The hulls were then stripped from the seeds. Molecular species and fatty acid distributions of triacylglycerols (TAGs), isolated from total lipids in the hulls, were analyzed by a combination of argentation thin‐layer chromatography (TLC) and gas chromatography. A modified argentation TLC procedure, developed to optimize the separation of the TAGs, provided 10 different groups of TAGs, based on both the degree of unsaturation and the total fatty acid chain‐length. Dilinoleolein (29.5—30.2 wt‐%), trilinolein (18.2—24.2 wt‐%), dilinoleopalmitin and dilinoleostearin (17.0—18.1 wt‐%), palmitoleolinolein and stearoleolinolein (11.4—14.0 wt‐%) and dioleolinolein (7.5—8.6 wt‐%) were the main TAGs detected after microwave roasting. However, roasting caused a significant decrease (p < 0.05), not only in TAG molecular species containing more than four double bonds, but also in the amounts of diene species present in TAGs. These results suggest that microwaves should affect TAGs in the hulls more significantly (p < 0.05) than those in the sunflower kernels. 相似文献
436.
Ryuji Okamoto Ryotaro Hashizume Noboru Suzuki Rie Ito Tomoko Tokuhara Hiroshi Fujiwara Ye Zhe Hiromasa Ito Takaya Abe Kaoru Dohi 《International journal of molecular sciences》2022,23(6)
Brain natriuretic peptide (BNP) levels are increased in both patients with heart failure with preserved (HFpEF) and reduced ejection fraction (HFrEF), but the reasons for this remain unclear. Our purpose was to examine whether serum-induced BNP (iBNP) expression partly contributes to increased BNP in patients with HFpEF. BNP reporter cardiomyocytes from pBNP-luc-KI mice were stimulated with serum from patients with HFpEF or HFrEF (n = 114 and n = 82, respectively). Luciferase activity was examined as iBNP and the iBNP-to-BNP ratio was evaluated. Patient characteristics and clinical parameters were compared, and multivariate regression analysis was performed to determine independent predictors of the iBNP-to-BNP ratio. Female sex and frequencies of atrial fibrillation, hypertension and the use of a calcium channel blocker (CCB) were higher in HFpEF. The iBNP-to-BNP ratio was significantly higher in HFpEF (26.9) than in HFrEF (16.1, p < 0.001). Multivariate regression analysis identified the existence of HFpEF as an independent predictor of the iBNP-to-BNP ratio after adjusting for all other measurements (β = 0.154, p = 0.032). Age, hemoglobin, CCB usage and deceleration time were also independent predictors (β = 0.167, p = 0.025; β = 0.203, p = 0.006; β = 0.138, p = 0.049; and β = 0.143, p = 0.049, respectively). These results indicate that the elevated BNP in patients with HFpEF is partly due to iBNP from the heart. 相似文献
437.
Takahiro Imanishi Yuta Fujiwara Yoshinari Sawama Yasunari Monguchi Hironao Sajiki 《Advanced Synthesis \u0026amp; Catalysis》2012,354(5):771-776
Geminal‐dichloromethyl derivatives could be efficiently synthesized by the highly chemoselective platinum on carbon‐catalyzed mono‐dechlorination of trichloromethyl substrates in dimethylacetamide (DMA) as a specific solvent at 25 °C under a hydrogen atmosphere. 相似文献
438.
Yoshiaki Kitamura Satoko Sako Azusa Tsutsui Yasunari Monguchi Tomohiro Maegawa Yukio Kitade Hironao Sajiki 《Advanced Synthesis \u0026amp; Catalysis》2010,352(4):718-730
A ligand‐free and heterogeneous palladium on carbon (Pd/C)‐catalyzed hetero‐Suzuki–Miyaura coupling reaction has been developed. The protocol enables the construction of both heterocyclic‐alicyclic and heterocyclic‐heterocyclic biaryl derivatives in good to excellent yields. Furthermore, Pd/C could be reused. The time‐course study clarified that palladium was leached into the reaction media as the reaction proceeded and then completely deposited on the carbon support. 相似文献
439.
Masahide Kaneko Kakeru Ninomiya Tomoko Hishida Yuki Takeuchi Kazushi Otani Maiko Nishibori 《Journal of the American Ceramic Society》2023,106(7):4480-4487
The mechanism underlying the enhancement of the conductivity of Li7La3Zr2O12 (LLZO), an oxide-based solid electrolyte that contains excess Li, was experimentally investigated through subvalent cation substitution. We prepared Sr-substituted Li-rich LLZO with high conductivity of the order of 10−4 S/cm by using a solid-state method. We investigated the mechanism underlying the conductivity enhancement via detailed structural analysis through Sr K-edge X-ray absorption near edge spectroscopy and X-ray diffraction and neutron powder diffraction analyses. The results suggested that the conductivity enhancement is due to the change in Li+ arrangement caused by the incorporation of excess Li into the LLZO lattice. 相似文献
440.
The baseline variation data on the chain‐length distribution profiles of endosperm starch were acquired for use as a criterion for variation among bread wheat (Triticum aestivum L.) cultivars/lines. A total of 126 starch samples isolated from closely related species belonging to the Triticum‐Aegilops group, i.e., five Triticum and 22 Aegilops species, were examined. Their side‐chains were debranched by isoamylase and chain‐length distribution profiles were determined by high‐performance anion exchange chromatography with pulsed amperometric detection (HPAEC‐PAD). An averaged chain‐length distribution profile calculated from all data indicated that the most abundant side‐chain had a degree of polymerization (DP) of 11 and its proportion based on relative peak area was 7.5%. The side‐chains were classified into four groups, and the average proportions of each group were as follows; DP 6–12, 28.5% (range 26.3–30.9%); DP 13–24, 48.6% (46.2–50.8%); DP 25–36, 13.7% (12.8–15.2%) and DP ≥37, 8.9% (7.2–10.6%). The chain‐length distribution profiles of Triticum and Aegilops species were essentially similar and no peculiar profile was observed. The range of the variation in the proportion of side‐chain groups, however, was comparable to the difference between waxy and non‐waxy bread wheat starches and among starches from wheat grown at different temperatures; this would affect the gelatinization and retrogradation properties of starch. 相似文献