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171.
172.
Satoshi Gotoda Nobuyoshi Takahashi Hirofumi Nakagawa Mitsuyuki Murakami Tomoko Takechi Tomozo Komura Toshiro Uchida Yasushi Takagi 《Pest management science》1998,52(4):309-320
A series of novel 6-(1,2,4-triazol-4-yl) chromone and -1-thiochromone (benzo[b]thiazin-4-one) derivatives was obtained by cyclisation via thiosemicarbazides which were prepared by reaction of hydrazines and the corresponding isothiocyanates. Their fungicidal activity was evaluated against the rice blast fungus Pyricularia oryzae. Of this series, 2,5,8-trimethyl-6-(1-propyl-5-thioxo-3-trifluoromethyl-1,2,4-triazol-4-yl) chromone, 6-(1-butyl-5-thioxo-3-trifluoromethyl-1,2,4-triazol-4-yl)-2,5,8-trimethylchromone, 6-(1-hexyl-3-methyl-5-thioxo-1,2,4-triazol-4-yl)-2,5,8-trimethylchromone and 6-(1-allyl-5-thioxo-3-trifluoromethyl-1,2,4-triazol-4-yl)-2,5,8-trimethylchromone were highly active (pEC50>6·0). Structure–activity relationship studies using the capacity factor k′ as a hydrophobicity index suggested that the log k′ optimum for 2,5,8-trimethyl-chromone and -1-thiochromone derivatives was around 1·0, equivalent to a log Pow value of c. 4·4. © 1998 SCI 相似文献
173.
Hiroshi Oikawa Yukihiko Matsuyama Masataka Satomi Yutaka Yano 《Fisheries Science》2008,74(5):1180-1186
The accumulation of paralytic shellfish poisoning (PSP) toxin in the crab Charybdis japonica was investigated in Kure Bay, when a bivalve Mytilus galloprovincialis, in the same water, showed toxicity caused by PSP toxin. In 2005, 17 specimens of the crab had PSP toxin over 4 MU/g in the
hepatopancreas, and the highest toxicity was at 37.4 MU/g. Since the regulation limit of PSP for crab hepatopancreas was set
in 2004, this is the first observation of regulatory level of PSP toxin in C. japonica. Unlike in the hepatopancreas of the crab, the hazardous level of the toxin was not detected in the muscle of the cephalothorax
and the appendage. The toxin accumulation in the crab was also investigated by feeding toxic mussels to the crab. The crab
retained the toxin mainly in the hepatopancreas, and the ratio of retention in the crab was from 12.9 to 24.6%. The toxin
profiles, shown in the feeding experiments, suggest that the transformation of PSP toxin occurs in the crab because dcGTX2
and dcGTX3 was detected in all crab specimens despite the lack of these analogs in the mussels used as feed. 相似文献
174.
As International Rice Genome sequencing Project 《分子植物育种》2007,5(2):180
As International Rice Genome sequencing Project (2005) demonstrated, the rice genome contains various transposons and about 13% of the genome is occupied by DNA transposons. 相似文献
175.
Yutaka Terada Masayoshi Tsuji Katsuro Hagiwara Kiyoshi Takahashi Chiaki Ishihara 《Veterinary parasitology》1995,60(3-4):221-228
Clearance of Theileria sergenti-infected bovine red blood cells (Bo-RBCs) from the blood circulation of severe combined immune deficiency (SCID) mice was studied to help understand the mechanisms of anemia developing in cattle infected with T. sergenti. For the clearance test, Bo-RBC samples having 2%, 58%, and 76% parasitemia and, as a control, parasite-free Bo-RBCs were prepared in the Bo-RBC-SCID mouse model. The T. sergenti-infected Bo-RBCs and the uninfected control Bo-RBCs were separately labeled with two, green and red, fluorescent dyes, mixed together, and injected intravenously into SCID mice. The blood samples collected at various time points were observed under a fluorescent microscope, and the numbers of green and red fluorescing RBCs were counted differentially to determine the clearance rates of T. sergenti-infected and uninfected Bo-RBCs. This test clearly demonstrated that the Bo-RBC samples having higher parasitemias were cleared faster from the blood circulation of SCID mice. The results suggest that the intravascular clearance system in SCID mice may have a mechanism by which T. sergenti-parasitized and non-parasitized Bo-RBCs are recognized and cleared differentially. 相似文献
176.
177.
低分子量热激蛋白Bmhsp19.9基因的表达 总被引:1,自引:0,他引:1
利用RT-PCR技术,对家蚕(Bombyx moil)低分子量热激蛋白Bmhsp19.9基因进行了定量表达分析。Bmhsp19.9在各组织中均有一定量的表达,但不同组织间的表达差异达10多倍,表达量丰富的组织是生长发育旺盛的组织,如精巢和卵巢,然后是丝腺、蛹等组织。其应激表达模式可分为3类,以其在精巢、后部丝腺和脂肪体中的强应激表达模式为主,经热刺激处理后其表达量有显著增加。经刺激诱导2h后其表达量达到最高,随后逐渐降低,在热刺激诱导12h后是未刺激的2~3倍,而此时Bmhsp19.9在脂肪体中的应激表达是其对照的10多倍。根据Bmhsp19.9在不同组织中的基本表达量、应激表达量和应激表达的持续时间各不相同,显示其与细胞分裂与分化等生命活动有一定联系。并认为其在后部丝腺、脂肪体、精巢、卵巢与血液中作用方式不一样,推测其作为分子伴侣在组织间的作用对象与作用效应也应有所差异。 相似文献
178.
Hiraku SASAKI Osamu KITAZUME Jun NONAKA Kenji HIKOSAKA Kenichi OTAWA Kikuji ITOH Yutaka NAKAI 《Animal Science Journal》2006,77(5):545-548
We observed the effects of a commercial microbiological additive (MA) on the beef manure composting process and investigated the changes in its physical and chemical components and microbial populations in the composting process. When beef manure compost was inoculated with the MA, its temperature rapidly increased at the beginning of the process, and after the first turning, the ammonia emission from the compost pile and nitrate production decreased quicker than that in the composting process without the MA. During the composting process, the manure inoculated with MA showed a larger numbers of mesophilic and thermophilic aerobes, and a smaller number of thermophilic anaerobes than in the process without the MA. These results suggested that mesophilic aerobes increased in number and metabolized ammonia by assimilation rather than nitrification to accelerate the temperature elevation in the composting process with the MA. 相似文献
179.
Masahito TANAKA Yuko KAMIYA Mitsuru KAMIYA Shigeru SHIOYA Yutaka NAKAI 《Animal Science Journal》2007,78(1):61-65
The antiradical function of sulfhydryl (SH) residue in dairy cattle plasma and the relationship of SH residue concentrations to other oxidative stress markers, ascorbic acid and thiobarbituric acid reactive substance (TBARS) in plasma were investigated. The concentration of reduced glutathione (GSH) in phosphate buffer solution (pH 7.6) and SH residues in dairy cattle plasma decreased significantly (P < 0.05) in vitro by the addition of peroxyradicals at 38°C, depending on incubation periods. The decrease of GSH concentration with the peroxyradical solution was partially protected by the addition of sodium ascorbate solution. A positive and significant correlation with SH residues and albumin concentration in the fresh plasma obtained from 15 dairy cattle was observed (P < 0.05). The SH residue concentration was not correlated with the TBARS concentration in plasma. The total ascorbic acid and SH residues concentration in the plasma correlated positively but not significantly (P < 0.10). These results suggested that SH residues in dairy cattle plasma play important part in the antiradical function. 相似文献
180.
Isolation and characterization of sulfur oxidizing bacteria from cattle manure compost 总被引:1,自引:0,他引:1
Hydrogen sulfide causes offensive odors. We attempted to isolate sulfur oxidizing bacteria (SOB) from cattle manure compost. A most probable number assay could not detect SOB by using a Cha medium which had been applied in order to isolate the SOB from active sewage. Cultivation using a Cha plate medium revealed 5.75 × 107 colony forming unit/g of bacteria. A single strain of SOB was isolated from a colony formed on the plates and identified as Halothiobacillus neapolitanus. This is the first report that H. neapolitanus has been found in cattle manure compost. 相似文献