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排序方式: 共有230条查询结果,搜索用时 15 毫秒
1.
Reduction of N2O in moist soil was inhibited completely by 10?2 atm C2H2 and partially by 10?5 atm C2H2. The effect of C2H4 was 104 times less than that of C2H2. Denitrification of NO?3 occurred in anaerobically or aerobically incubated waterlogged soil and in anaerobic but not in aerobic moist soil. In the absence of C2H2 there was transient accumulation of N2O. In the presence of C2H2 there was stoichiometric conversion of NO?3 to N2O. Some kinetics of the reduction of N2O and of NO?3 to N2O are presented. Denitrification of 1 μg added NO?3-N.g? could be measured within 1 h. Stoichiometries of production of N2O from NO?2 and NO?3, respectively, and production of CO2 attributable to denitrification were consistent with reported energy yields. Reduction of C2H2 to C2H4 occurred immediately following complete denitrification of added NO?3. The incubation of soil in the presence and in the absence of C2H2 thus permits assay of both denitrification and N2 fixation and provides information on the mole fraction of N2O in the products of denitrification. 相似文献
2.
Arata Katayama Hong-Ying Hu Mamie Nozawa Sayuri Takahashi Koichi Fujie 《Soil Science and Plant Nutrition》2013,59(6):841-846
Based on the respiratory quinone profile, changes in the structure of microbial communities in the soil samples from Nagoya University Farm were monitored after the treatment with 1% of a mixture of glucose and peptone. Samples of two soils differing in the fertilization history were examined: CF-soil with the application of only chemical fertilizers and FYM-soil with the application of only farmyard manure at a high rate. In the CF-soil, the amount of water-soluble organic carbon (WOC), indicator of the mixture of glucose and peptone, decreased to the original level after 14 d. After 7 d, the soil pH reached the maximum level, then decreased gradually. Changes in the inorganic nitrogen levels in the water extract also reflected the 14-d period of mineralization. The amount of respiratory quinones reached maximum levels after 7 d and gradually decreased, reflecting the changes in the microbial biomass. The quinone composition significantly changed during the 14-d period and returned to a profile similar to the original one after 28 d. Diversity of quinones significantly decreased during the 14-d period due to the predominance of ubiquinone with 9 isoprenoid units. In the FYM-soil, the amount of WOC decreased to the original level after 1 d, and the pH and inorganic nitrogen levels in the water extract reflected the one-day mineralization period, and nitrification started after 3 d. Although the amount of quinones indicated an increase in the microbial biomass for 14 d, the quinone composition did not change. These findings suggested that long-term application of farmyard manure resulted in stable microbial communities in response to the incorporation of organic matter in soil. 相似文献
3.
Loida O. Casalme Keisuke Katayama Yoshiki Hayakawa Kensuke Nakamura Arisa Yamauchi Yasuyuki Nogata Erina Yoshimura Fuyuhiko Matsuda Taiki Umezawa 《Marine drugs》2022,20(2)
Some derivatives of dolastatin 16, a depsipeptide natural product first obtained from the sea hare Dolabella auricularia, were synthesized through second-generation synthesis of two unusual amino acids, dolaphenvaline and dolamethylleuine. The second-generation synthesis enabled derivatizations such as functionalization of the aromatic ring in dolaphenvaline. The derivatives of fragments and whole structures were evaluated for antifouling activity against the cypris larvae of Amphibalanus amphitrite. Small fragments inhibited the settlement of the cypris larvae at potent to moderate concentrations (EC50 = 0.60-4.62 μg/mL), although dolastatin 16 with a substituent on the aromatic ring (24) was much less potent than dolastatin 16. 相似文献
4.
Hashimoto S Takakura R Yoshinari M Minam N Yamada M Imai H Kashim N 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2000,62(6):647-650
To characterize factors affecting the number of bovine oocytes recovered transvaginally, a regression analysis was performed between the responsiveness to multiple-ovulation treatment and the number of oocytes recovered transvaginally. The number of embryos recovered following multiple-ovulation treatment and the number of oocytes recovered transvaginally increased when the number of follicles to be aspirated transvaginally increased (P<0.05. P<0.01). The number of cumulus-oocyte complexes recovered transvaginally also increased when the number of oocytes to be aspirated transvaginally increased (P<0.001). However, the number of viable embryos that recovered following multiple-ovulation treatment had no relation to the number of cumulus-oocyte complexes recovered transvaginally. These results suggested that more oocytes can be recovered from donors that have a high responsiveness to multiple-ovulation treatment. 相似文献
5.
Kazunori Fuke Naofumi Hozumi Yoshinari Enami Kazuho Matsuura Akitoshi Tajimi 《Journal of General Plant Pathology》2006,72(1):74-75
Anthracnose disease was found on centipede grass [Eremochloa ophiuroides (Munro) Hack.] planted as a ground cover on paddy field levees in Shiga Prefecture in 2004. The symptoms were ear blight,
stalk blight, and leaf spots. The causal fungus was morphologically identified as Colletotrichum caudatum (Sacc.) Peck. This is the first report of centipede grass anthracnose caused by C. caudatum. 相似文献
6.
Masaaki Katayama Yasuhiko Okamura Shunsuke Shimamura Rieko Katayama Hiroaki Kamishina Yuji Uzuka 《Research in veterinary science》2014
Graft perfusion with cold heparinized saline has known to induce ischemia and reperfusion injury in feline kidney transplantation. In this study, the effects of phosphate-buffered sucrose solution and heparinized saline solution on early kidney graft function were compared in feline kidney autotransplantation. Perfusion of grafts with or without hypothermic storage with chilled phosphate-buffered sucrose solution prevented ischemia and reperfusion injury despite a very short ischemic time. The results of our study suggest that phosphate-buffered sucrose perfusion and storage solution should be effective to reduce ischemia and reperfusion injury despite a very short ischemic time in feline kidney transplantation. 相似文献
7.
Amimoto K Oishi E Yasuhar H Sasak O Katayama S Kitajima T Izumida A Hirahara T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(8):879-883
The protective effects of Clostridium sordellii lethal toxin (LT) and hemorrhagic toxin (HT) toxoids against challenge with spores in guinea pigs were investigated. Purified LT and partially purified HT were obtained from the culture supernatant of C. sordellii strain 3703, and then were treated with formalin to make toxoids. LT. HT and combined LT and HT (LT/HT) toxoid vaccines were prepared by mixing each toxoid with an aluminum phosphate gel as adjuvant. Guinea pigs immunized twice with the respective toxoid vaccines were challenged with spores of strains 3703 or KZ1047. The latter strain does not produce HT. LT toxoid vaccine conferred protection against challenge with strain KZ1047, but not strain 3703, in guinea pigs. All guinea pigs immunized with HT toxoid vaccine died after challenge with spores of either strain. LT/HT toxoid vaccine gave complete protection against challenge with spores of strains 3703 and KZ1047 to guinea pigs. These results suggest that not only LT toxoid, but also HT toxoid, are essential protective antigens of C. sordellii. 相似文献
8.
Tadashi Katayama Michiharu Kobayashi Azuma Okuda 《Soil Science and Plant Nutrition》2013,59(4):101-106
In previous papers (1,2), it was reported that in cultures of R. capsulatus mixed with other heterotrophic bacteria nitrogen fixation is accelerated and there is some production of slime substances (3), exchange of pyruvic acid (4–6), amino acids, carbohydrates (7) and others in these mixed systems. There is also symbiotic association between R. capsulatus and other heterotrophic bacteria (Azotobacter) in nature (8). 相似文献
9.
Therapeutic soft contact lenses (TSCL) were applied to a thoroughbred racehorse with corneal ulcer refractory to topical medication. The insertion of the TSCL was conducted on day 36 using a nose twitch under sedation, auriculopalpebral nerve block, and topical anesthesia. The lens was retained, with the duration of wear lasting 114 days. Ocular pain improved immediately and fluorescein tests were negative 17 days after insertion. The horse was able to undergo training and ran in two races while wearing the TSCL. Thus a TSCL was found to be clinically useful for treating corneal ulcers in racehorses. 相似文献
10.
Takeshi Katayama Jyoji Tsutsui Kazuo Tsueda Takao Miki Yasuhiro Yamada Murao Sogo 《Journal of Wood Science》2000,46(6):458-465
When (±)--oxo-guaiacylglycerol--(vanillic acid) ether (1) is degraded byFusarium solani M-13-1, the-ketone is initially reduced to giveerythro andthreo guaiacylglycerol--(vanillic acid) ethers (2), arylglycerol--aryl ethers, both of which are enantiomerically pure. The absolute configuration in each2 was determined by Mosher's method; the products were converted to,-di-(R)--methoxy--trifluoromethylphenylacetates (MTPA esters) (3) oferythro (-)- andthreo (+)-veratrylglycerol--(methyl vanillate) ethers (3), whose1H nuclear magnetic resonance (NMR) spectra were examined and compared with those of four di-(R)-MTPA ester (3) diastereomers from chemically synthesizederythro (±)-3 andthreo (±)-3. To assign the- and-MTPA-OCH3 peaks, the1H NMR scans of several compounds that have substructures of 3 and their 3,4,5-trimethoxyphenyl analogues were examined. When a racemic alcohol reacts with (R)-MTPA to give a pair of (R)-MTPA ester diastereomers, the value was defined as the absolute value of the difference in the1H chemical shifts of the peak between the diastereomers. It was found that the values of-MTPA-OCH3 were larger than those of-MTPA-OCH3 owing to a shielding effect of the veratryl ring located on the-MTPA-OCH3, and that the-MTPA-OCH3 peaks in the 3,4,5-trimethoxyphenyl compounds shifted downfield relative to those in the veratryl compounds. On the basis of the1h NMR data of (R)-MTPA esters, the absolute configuration of the four chemically prepared diastereomers (3) were determined. The catabolicerythro
3 [fromerythro (-)-3] andthreo
3 [fromthreo (+)-3] were identical to (R, S, R)-erythro
3 and (R, S, S)- threo
3, respectively. An hydrogen species in the fungal reduction would attack the-ketone fromre-face of both (R)-1 and (S)-1, givingerythro (S, R)-2 andthreo (S, S)-2, respectively.Part of this paper was presented at the 33rd Lignin Symposium, Tsukuba, November 1988 相似文献