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排序方式: 共有267条查询结果,搜索用时 15 毫秒
91.
92.
Kodama H Denso Nakagawa T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(4):405-408
Humic substances are formed during the decomposition of organic matter in humus, and are found in many natural environments in which organic materials and microorganisms have been present. In the present study, oral administration of humus extract to common carp (Cyprinus carpio L.) induced effective protection against experimental atypical Aeromonas salmonicida infection. Mortality of fish and development of skin lesions such as hemorrhages and ulcers were significantly suppressed in carp treated with 10%, 5% or 1% humus extract adsorbed on dry feeding pellets. The median surviving days was also greater in fish treated with 10% or 5% humus extract than in untreated fish. Atypical A. salmonicida was isolated from ulcerative lesions of part of dead fish, but Aeromonas hydrophila and Flavobacterium sp. were also isolated from these fish, verifying bacterial population changes during the progression of skin lesions. These results clearly show that treatment of fish with humus extract is effective in preventing A. salmonicida disease. 相似文献
93.
The macroscopic motion of liquids on a flat solid surface was manipulated reversibly by photoirradiation of a photoisomerizable monolayer covering the surface. When a liquid droplet several millimeters in diameter was placed on a substrate surface modified with a calix[4]resorcinarene derivative having photochromic azobenzene units, asymmetrical photoirradiation caused a gradient in surface free energy due to the photoisomerization of surface azobenzenes, leading to the directional motion of the droplet. The direction and velocity of the motion were tunable by varying the direction and steepness of the gradient in light intensity. The light-driven motion of a fluid substance in a surface-modified glass tube suggests potential applicability to microscale chemical process systems. 相似文献
94.
Antioxidative activity of green tea polyphenol in cholesterol-fed rats 总被引:17,自引:0,他引:17
This study investigated the effects of green tea polyphenol on the serum antioxidative activity and cholesterol levels of cholesterol-fed rats and compared them with those of probucol, an antioxidant hypocholesterolemic agent. To evaluate the antioxidative activity, the susceptibility to oxidative modification of low-density lipoprotein (LDL) isolated from the serum of cholesterol-fed rats was measured, as was the serum antioxidative activity using the spontaneous autoxidation system of brain homogenate. Administration of green tea polyphenol effectively inhibited LDL oxidation and elevated serum antioxidative activity to the same degree as probucol. However, higher amounts of polyphenol than probucol needed to be administered to reduce the total, free, and LDL cholesterol levels. Furthermore, green tea polyphenol increased the levels of high-density lipoprotein (HDL) cholesterol, leading to dose-dependent improvement of the atherogenic index, an effect that was not seen with probucol. Thus, green tea polyphenol may exert an antiatherosclerotic action by virtue of its antioxidant properties and by increasing HDL cholesterol levels. 相似文献
95.
Masahiko Nakagawa 《林业研究》2013,24(1):131-136
I developed a weeding-duration model for Sakhalin fir (Abies sachalinensis (Fr. Schmidt) Masters) plantations that employs a generalized linear model. The number of years following planting that weeding is necessary is the response variable, and elevation, slope steepness, maximum snow depth, annual precipitation, geology, soil, site index, slope aspect, and vegetation type are explanatory variables. Among the explanatory variables, geology, soil, slope aspect, and vegetation type are categorical data. A Poisson distribution is assumed for the response variable, with a log-link function. Elevation, slope steepness, maximum snow depth, annual precipitation, site index, and vegetation type had a significant effect on weeding duration. Among the eight models with the smallest Akaike information criterion (AIC), I chose the model with no multicollinearity among the explanatory variables. The weeding-duration model includes site index, maximum snow depth, slope steepness (angle) and vegetation type as explanatory variables; elevation and annual precipitation were not included in the selected model because of multicol- linearity with maximum snow depth. This model is useful for cost-benefit analyses of afforestation or reforestation with Abies sachalinensis. 相似文献
96.
97.
Hadi Mosallanejad Luc Swevers Yoshiaki Nakagawa 《Pesticide biochemistry and physiology》2008,92(2):70-76
The activity profile of the most recent commercial non-steroidal ecdysteroid agonist chromafenozide (ANS-118), was evaluated on a comparative basis to methoxyfenozide (RH-2485) that is to date the most potent commercial agonist against Lepidoptera. This was done first at the molecular and cellular level regarding its induction activity of an ecdysteroid-responsive reporter gene and its cell proliferation inhibition activity, and subsequently at the level of larvicidal toxicity. For in vitro experiments three ecdysteroid-responsive insect cell lines were used: Drosophila melanogaster (Diptera) S2 cells, Bombyx mori (Lepidoptera) Bm5 cells and Spodoptera exigua (Lepidoptera) Se4 cells. The in vivo toxicity was scored against two major lepidopteran pests in the world, the beet armyworm S. exigua and the cotton leafworm Spodoptera littoralis. In vitro results revealed that chromafenozide and methoxyfenozide are highly potent against lepidopteran cells compared to dipteran cells, supporting the lepidopteran-specificity of these compounds. Interestingly, in the reporter gene induction experiments and proliferation inhibition experiments, a slightly higher efficacy was observed in S2 compared to Bm5 cells at high concentrations of chromafenozide and methoxyfenozide. Our analysis shows the high potency and efficacy of the chromafenozide compound as an ecdysteroid agonist towards lepidopteran insects at a level that is similar to methoxyfenozide. 相似文献
98.
Michio Kurata Manabu Seoka Yoshizumi Nakagawa Yasunori Ishibashi Hidemi Kumai Yoshifumi Sawada 《Aquaculture Research》2012,43(9):1296-1305
Initial swimbladder inflation (ISI) of Pacific bluefin tuna (PBT), Thunnus orientalis, larvae was studied to increase the survival of cultured larvae. Experiment 1 was conducted to explore promotion and inhibition of ISI under different water surface conditions; including the use of surface skimmer to remove autogenous surface substances (SS), covering the water surface with liquid‐paraffin‐layer (LP) and oil film (OF), and a control (non‐treatment, NT). Significantly higher inflation frequency was observed in SS (62.2%) than NT (11.9%), LP (2.7%) and OF (3.9%). This indicates that ISI in PBT larvae can be promoted by removal of surface substances on rearing water which inhibit larval air gulping. Experiment 2 aimed to elucidate proper day of larval age to start skimming for promoting ISI with four different periods of oil film removal: from 3 to 8 (SF3D), 4 to 8 (SF4D), 5 to 8 (SF5D), 6 to 8 (SF6D) days‐post‐hatch (dph). Significant improvement in ISI frequency was observed in SF3D (80.2%) but the frequency was very poor in SF4D, SF5D, and SF6D (17.8–7.5%). This implies the need of oil film removal without missing a narrow window, 1 day of 3 dph, to promote ISI in practical PBT larviculture. 相似文献
99.
Brassinosteroids are plant steroid hormones that are essential for plant growth. When germinated rice seeds were treated with brassinolide (BL), stems were elongated and root spiral formation was observed at 5 nM of BL. Such root spiral formation was not induced by other plant hormones such as auxin and gibberellin. Since weak non-steroidal brassinolide-like compound (NSBR1) also induced spiral formation, this root spiral induction can be used as the index in the search for BL-like compounds. 相似文献
100.
Application of single‐step genomic best linear unbiased prediction with a multiple‐lactation random regression test‐day model for Japanese Holsteins 下载免费PDF全文
Toshimi Baba Yusaku Gotoh Satoshi Yamaguchi Satoshi Nakagawa Hayato Abe Yutaka Masuda Takayoshi Kawahara 《Animal Science Journal》2017,88(8):1226-1231
This study aimed to evaluate a validation reliability of single‐step genomic best linear unbiased prediction (ssGBLUP) with a multiple‐lactation random regression test‐day model and investigate an effect of adding genotyped cows on the reliability. Two data sets for test‐day records from the first three lactations were used: full data from February 1975 to December 2015 (60 850 534 records from 2 853 810 cows) and reduced data cut off in 2011 (53 091 066 records from 2 502 307 cows). We used marker genotypes of 4480 bulls and 608 cows. Genomic enhanced breeding values (GEBV) of 305‐day milk yield in all the lactations were estimated for at least 535 young bulls using two marker data sets: bull genotypes only and both bulls and cows genotypes. The realized reliability (R2) from linear regression analysis was used as an indicator of validation reliability. Using only genotyped bulls, R2 was ranged from 0.41 to 0.46 and it was always higher than parent averages. The very similar R2 were observed when genotyped cows were added. An application of ssGBLUP to a multiple‐lactation random regression model is feasible and adding a limited number of genotyped cows has no significant effect on reliability of GEBV for genotyped bulls. 相似文献