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681.
Hu Q Yang Q Yamato O Yamasaki M Maede Y Yoshihara T 《Journal of agricultural and food chemistry》2002,50(5):1059-1062
Five compounds oxidizing canine erythrocytes were isolated from an aqueous ethanol garlic extract by silica gel column chromatography and preparative thin-layer chromatography. On the basis of nuclear magnetic resonance, infrared spectroscopy, and mass spectrometry, they were identified as three known compounds: bis-2-propenyl trisulfide (1), bis-2-propenyl tetrasulfide (2), and bis-2-propenyl pentasulfide (3) as well as two novel compounds, bis-2-propenyl thiosulfonate (4) and trans-sulfuric acid allyl ester 3-allylsulfanyl-allyl ester (5). A mixture of compounds 1-3 and compounds 4 and 5 induced methemoglobin formation in canine erythrocyte suspension in vitro resulting in the oxidation of canine erythrocytes. These groups of characteristic organosulfur compounds contained in garlic probably contribute to oxidations in blood. The constituents of garlic have the potential to oxidize erythrocytes and hemoglobin, suggesting that foods containing quantities of garlic should be avoided for feeding dogs. 相似文献
682.
The antigenic and allergenic activities of ovomucoid (OM) remaining in soluble fractions of pasta-like model samples of wheat flour mixed with egg white were investigated by ELISA competitive inhibition and immunoblotting analyses using a rabbit anti-OM IgG and the serum IgE specific for OM in patients allergic to egg white. The mixture of egg white and wheat flour of soft, hard, and durum varieties was kneaded for 10-50 min and benched for 1 h at RT, and then small pieces of the dough were heated in boiling 1% NaCl solution for 15 min. Even before heating, only after the kneading for 30 min or more, but not after kneading for only 20 min, followed by the benching, the antigenic activity of OM which remained in the phosphate-buffered saline extract from the dough markedly decreased. Almost no antigenic activity of OM was detected in the extracts of heated samples. Furthermore, in the extracts of heated durum samples, only a trace of or almost no IgE-reactive OM was detected against the five patients' sera. These reductive effects of wheat on the OM antigenicity and allergenicity were more remarkable in the durum variety than in the others. No detectable proteins were extracted with 1% SDS from the heated samples, whereas OM was extracted with 1% SDS containing 10% 2-mercaptoethanol, suggesting heat-induced polymerization through intermolecular disulfide bonds among OM and wheat. 相似文献
683.
Ippei Iiyama Toshiki Fujimoto Osamu Nagata Shuichi Hasegawa 《Soil Science and Plant Nutrition》2005,51(3):313-322
To evaluate the coexistence of agricultural managements and wetland ecosystem conservation, the Bibai mire, an ombrotrophic mire in Hokkaido, Japan, was selected as an experimental site that had been affected by neighboring agricultural managements. Since the lowering of the level of the groundwater table in the peripheral area of the mire had threatened indigenous vegetations, keeping the groundwater table shallow by trench irrigation seemed to be an effective measure to recover the original vegetation. The objective of the present study was to quantify the amount of water and the effective area of trench irrigation required in a bamboo-invading area in a pristine mire. We constructed a trench 28 m long and irrigated at the rate of 2.22 m3 d−1 in a bamboo-invading area in the mire. And to analyze the hydro-meteorological conditions under the trench irrigation, we measured the saturated hydraulic conductivity of the peat layer (3.8 × 10−3 cm s−1 ), the evapotranspiration rate (2.80 mm d−1 ), the depth of the non-irrigated groundwater table (0.15 m) and the surface gradient (0.00493). In addition, using the mass conservation equation and Darcy's law, we derived a steady state model of the level of the groundwater table formed by trench irrigation, which required the five parameters mentioned above. The irrigated water spread over a distance of only about 15 m to both sides of the trench. The model also estimated that the distance for the irrigated area was 14.6 m and we concluded that the irrigated area was limited within a distance of 20 m distances to both sides of the trench and that the irrigation rate per unit trench length did not exceed 0.12 m2 d−1 for realistic values of the evapotranspiration rate and the saturated hydraulic conductivity in peatland. 相似文献
684.
Masaki KATO Daiki KAWASHIMA Yui ITO Osamu YAMAMOTO Hiromi NAKAJIMA Takuya OIZUMI Kaori SHIMIZU Yasuo INOSHIMA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(2):304
Nasal papules and oral ulcers were observed in calves that were group-housed at a dairy farm. The calves were diagnosed with bovine papular stomatitis (BPS) due to parapoxvirus (PPV) infection based on virologic examinations using polymerase chain reaction to detect PPV. To prevent the spread of BPS, we isolated the affected calves, made procedural changes so that the affected herd was managed after the healthy herd, disinfected the bedding with slaked lime, disinfected the stalls and fences with invert soap, and changed the animals’ feed to soft grass which does not damage the oral cavity. As a result, we succeeded in control the infection quickly. 相似文献
685.
686.
Dietary docosahexaenoic acid can alter the surface expression of CD4 and CD8 on T cells in peripheral blood 总被引:1,自引:0,他引:1
Sasaki T Kanke Y Nagahashi M Toyokawa M Matsuda M Shimizu J Misawa Y Takita T 《Journal of agricultural and food chemistry》2000,48(4):1047-1049
The effect of dietary docosahexaenoic acid (DHA) on T cell states in peripheral blood was investigated. Weanling male C57Bl/6N mice were kept on one of three 10% fat diets containing various amounts of DHA and linoleic acid for 4 weeks. Changing the concentration of dietary DHA did not alter the proportion of T cells expressing CD4 or CD8. However, increasing the concentration of dietary DHA lowered the expression of CD4 and CD8 on the cell surface. The decreased expression of these surface molecules involved in T cell proliferation has serious implications in the role of DHA as an immunosuppressant. 相似文献
687.
To compare the distributions of Raffaelea quercivora hyphae within seedlings of a susceptible species, Quercus crispula, and a resistant species, Q. glauca, we examined water conductance at transverse sections. Raffaelea quercivora was inoculated into the stems of seedlings in July (summer) and October (autumn) and observed by light and fluorescence microscopy at 1 and 2 weeks after inoculation. The hyphal distribution patterns expressed as the Iδ index differed between the species at each occasion. The hyphal growth was wider in Q. crispula than in Q. glauca in July inoculation, but did not differ in October inoculation. Non‐conductive sapwood in Q. crispula in transverse section was wider than that in Q. glauca at each occasion. The differences of hyphal growth and hyphal distribution patterns between species as little as 1 week after inoculation reflect differences in host susceptibility to the fungus. 相似文献
688.
摘出垂体12 h 后的卵泡孕酮(P_4)浓度显著下降.单独添加 LH 时第一卵泡(F_1)的P_4浓度显著增加,同时添加 LH 和 FSH 时,所有卵泡的颗粒层 P_4浓度恢复到对照的水平.但是单独添加 FSH 时无促进作用.LH 和 FSH 的处理对卵泡的卵泡膜 P_4浓度影响极小.在细胞培养液中添加 LH 和 FSH 可以促进颗粒层的 P_4合成,这种反应以 F_1最为明显.LH 和 FSH同时添加时对颗粒层 P_4合成有显著效果,但是对卵泡膜 P_4合成无明显促进作用.表明 P_4在 LH和 FSH 的协同调控下,主要在 F_1的颗粒层中合成. 相似文献
689.
Chollet M Guerin L Uchida N Fukaya S Shimoda H Ishikawa T Matsuda K Hasegawa T Ota A Yamochi H Saito G Tazaki R Adachi S Koshihara SY 《Science (New York, N.Y.)》2005,307(5706):86-89
We report that the organic salt (EDO-TTF)2PF6 with 3/4-filled-band (1/4-filled in terms of holes), which forms an organic metal with strong electron and lattice correlation, shows a highly sensitive response to photoexcitation. An ultrafast, photoinduced phase transition from the insulator phase to the metal phase can be induced with very weak excitation intensity at near room temperature. This response makes the material attractive for applications in switching devices with room-temperature operation. The observed photo-induced spectroscopic change shows that this photoinduced phase transition process is caused by the cooperative melting of charge ordering assisted by coherent phonon generation. 相似文献
690.