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51.
52.
The relationship between the optimum concentration of mitogen which induces lymphocyte blastogenic response and the receptor occupancy by mitogen was investigated. The receptor occupancies which induced maximal blastogenic activity in equine, bovine and canine peripheral blood lymphocytes (PBL) were 31.1 per cent, 26.5 per cent and 38.4 per cent with phytohaemagglutinin-P, and 48.2 per cent, 17.9 per cent and 24.5 per cent with concanavalin A, respectively. The data clearly show that each animal species had its own optimum concentration of mitogen for stimulation of PBL. Optimum concentration for blastogenesis and number of binding sites of each mitogen had a good correlation with each other for all three species. 相似文献
53.
Biotransformation of alpha-terpineol by the common cutworm (Spodoptera litura) larvae was investigated. alpha-Terpineol was mixed in an artificial diet, and the diet was fed to the larvae (fourth-fifth instar) of S. litura. Metabolites were isolated from the frass and analyzed spectroscopically. Main metabolites were 7-hydroxy-alpha-terpineol (p-menth-1-ene-7,8-diol) and oleuropeic acid (8-hydroxy-p-menth-1-en-7-oic acid). Intestinal bacteria from the frass of larvae did not participate in the metabolism of alpha-terpineol. alpha-Terpineol was preferentially oxidized at the C-7 position (allylic methyl group) by S. litura larvae. 相似文献
54.
Toyoshima K Noguchi R Hosokawa M Fukunaga K Nishiyama T Takahashi R Miyashita K 《Journal of agricultural and food chemistry》2004,52(8):2372-2375
Sardine oil was obtained by centrifugation of surimi wastewater without heating or chemical refining. This oil (CE) showed light yellow color and the peroxide value was less than 1.0 meq/kg. The main lipid class of CE was triacylglycerol (TG) (>99%). These features indicate that CE can be directly used as food materials without further purification. Commercial sardine oil (CO) is usually prepared via some kind of refining process with high temperature (250 degrees C) and chemical treatment. The comparative study on the physiological effects of these sardine oils (CE and CO) revealed that the dietary sardine oils were more effective in reducing abdominal fat pads, plasma total cholesterol, and TG levels of rats than was a soybean oil diet (control). Furthermore, these effects were greater in CE than CO, although there was little difference in the fatty acid composition of both oils. Although the main lipid class of CE was TG (>99%), CE was prepared by centrifugation from surimi waste and directly used as dietary fat without further purification. Therefore, CE may contain some kinds of minor components, which could be attributed to the higher physiological activity of CE. To reveal the involvement of the minor compounds in CE, we prepared TG from CE by column chromatography and measured its effect on lipid metabolism of rats. TG from CE also showed the reducing effects on abdominal fad pads and plasma lipid levels. The effect of TG from CE was almost the same as that of original CE, suggesting that the higher nutritional activity of CE than CO may not be due to the minor compounds in CE. 相似文献
55.
The hydrogen-bonding structure of water-ethanol in whiskey was examined on the basis of (1)H NMR chemical shifts of the OH of water and ethanol. Phenolic acids and aldehydes (gallic, vanillic, and syringic acids; vanillin and syringaldehyde) exhibited their structure-making effects regardless of the presence or absence of 0.1 or 0.2 mol dm(-3) acetic acid. The OH-proton chemical shifts were measured for 32 malt whiskey samples of a distillery, aged for 0-23 years in five different types of casks. The OH-proton chemical shift values of the whiskies shifted toward the lower field in proportion to their contents of total phenols. It can be concluded that the strength of the hydrogen bonding in aged whiskies is directly predominated by acidic and phenolic components gained in oak wood casks and not dependent on just the aging time. 相似文献
56.
Sato M Ishikawa T Ujihara N Yoshida S Fujita M Mochizuki M Asada A 《Science (New York, N.Y.)》2011,332(6036):1395
The moment magnitude (M(w)) = 9.0 2011 Tohoku-Oki mega-thrust earthquake occurred off the coast of northeastern Japan. Combining Global Positioning System (GPS) and acoustic data, we detected very large sea-floor movements associated with this event directly above the focal region. An area with more than 20 meters of horizontal displacement, that is, four times larger than those detected on land, stretches several tens of kilometers long along the trench; the largest amount reaches about 24 meters toward east-southeast just above the hypocenter. Furthermore, nearly 3 meters of vertical uplift occurred, contrary to observed terrestrial subsidence. 相似文献
57.
Matsuishi S Toda Y Miyakawa M Hayashi K Kamiya T Hirano M Tanaka I Hosono H 《Science (New York, N.Y.)》2003,301(5633):626-629
We removed approximately 100% of clathrated oxygen ions from the crystallographic cages in a single crystal of 12CaO.7Al2O3, leading to the formation of high-density (approximately 2 x 10(21) cm-3) electrons highly localized in the cages. The resulting electron forms a structure that we interpret as an F+ center and migrates throughout the crystal by hopping to a neighboring cage with conductivity approximately 100 siemens per centimeter, demonstrating that the encaged electron behaves as an anion. The electron anions couple antiferromagnetically with each other, forming a diamagnetic pair or singlet bipolaron. The resulting [Ca24Al28O64]4+(4e-) may be regarded as a thermally and chemically stable single crystalline "electride." 相似文献
58.
59.
Yurimoto H Abe K Abe M Ebihara M Fujimura A Hashiguchi M Hashizume K Ireland TR Itoh S Katayama J Kato C Kawaguchi J Kawasaki N Kitajima F Kobayashi S Meike T Mukai T Nagao K Nakamura T Naraoka H Noguchi T Okazaki R Park C Sakamoto N Seto Y Takei M Tsuchiyama A Uesugi M Wakaki S Yada T Yamamoto K Yoshikawa M Zolensky ME 《Science (New York, N.Y.)》2011,333(6046):1116-1119
Meteorite studies suggest that each solar system object has a unique oxygen isotopic composition. Chondrites, the most primitive of meteorites, have been believed to be derived from asteroids, but oxygen isotopic compositions of asteroids themselves have not been established. We measured, using secondary ion mass spectrometry, oxygen isotopic compositions of rock particles from asteroid 25143 Itokawa returned by the Hayabusa spacecraft. Compositions of the particles are depleted in (16)O relative to terrestrial materials and indicate that Itokawa, an S-type asteroid, is one of the sources of the LL or L group of equilibrated ordinary chondrites. This is a direct oxygen-isotope link between chondrites and their parent asteroid. 相似文献
60.