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排序方式: 共有642条查询结果,搜索用时 4 毫秒
1.
Amin A. Nomeir Nicolas P. Hajjar Ernest Hodgson Walter C. Dauterman 《Pesticide biochemistry and physiology》1980,13(2):112-120
EPN is twice as toxic as EPNO to house flies from both the Diazinon-resistant strain and the susceptible strain. EPN and EPNO are also eight times more toxic to the susceptible than the resistant strain. This is due to the ability of the resistant strain to metabolize these compounds to a greater extent. Metabolism by the glutathione S-transferases present in the 100,000g supernatant is more extensive than that by the NADPH-dependent microsomal mixed-function oxidases. The glutathione S-transferases are the major route of metabolism for EPN and appear to be the principal mechanism conferring resistance. EPN was metabolized by the microsomal fraction via oxidative desulfuration to the oxygen analog, EPNO, and by oxidative dearylation to p-nitrophenol. EPNO was metabolized by the same system to p-nitrophenol and desethyl EPNO as well as to an unknown metabolite. The soluble fraction metabolized EPN to p-nitrophenol, S-(p-nitrophenyl)glutathione, O-ethyl phenylphosphonothioic acid, and S-(O-ethyl phenylphosphonothionyl)glutathione. The identification of the latter conjugate demonstrates a new type of metabolite of organophosphorus compounds. EPNO was metabolized by the soluble fraction to p-nitrophenol and S-(p-nitrophenyl)glutathione. 相似文献
2.
Five cestode species parasitizing ruminants were found for the first time in Afghanistan: Moniezia benedeni, M. expansa, Avitellina centripunctata, Stilesia globipunctata, and Thysaniezia giardi. 相似文献
3.
Amin Oujifard Jafar Seyfabadi Abdolmohammad Abedian Kenari Masood Rezaei 《Aquaculture International》2012,20(1):117-129
Replacement of fish meal (FM) with rice protein concentrate (RPC) as a practical diet for the Pacific white shrimp, Litopenaeus vannamei, was evaluated. Five isonitrogenous (36.6% protein) diets, formulated by replacing 0, 25, 50, 75, and 100% of FM by RPC,
were fed to shrimp (initial weight of 6.99 ± 0.08 g) five times daily to satiation for 60 days. Relatively high final weight
(FW 17.64–18.25 g) and weight gain (WG 10.81–11.39 g) were obtained in treatments up to 50% of the plant protein inclusion.
Above this inclusion level, FW (14.93–14.35 g) and WG (7.68–7.23 g) were reduced. Survival was high (≥95%) and similar for
all diets. There were no significant differences (P > 0.05) in tail-muscle composition (moisture, protein, lipid, and ash) among different dietary treatments. Dispensable and
indispensable amino acids of the tail muscle of shrimp fed with 25, 50, and 75% RPC were significantly higher than the FM
(0%) and 100% RPC diets. A decreasing trend in apparent digestibility coefficient (excluding dry matter) for crude protein
(90.52–52.41), ether extract (94.11–80.03), organic matter (87.25–50.16), and gross energy (89.41–55.24) was observed at higher
RPC inclusion rates. The results suggest that RPC meal can be a potential candidate for FM replacement up to 50% of the protein
in shrimp diets. 相似文献
4.
In order to investigate the effect of nitrogen (N) and sulfur (S) fertilizers on yield and seed quality of three canola cultivars, a factorial based on randomized complete block experiment was conducted during 2005–2006 in Iran. Treatments included four nitrogen rates (0, 75, 150, and 225 kg N ha?1 source of urea), four sulfur rates (0, 100, 200, and 300 kg S ha?1), and three cultivars (‘Pf’, ‘Option-500’, and ‘Hyola-401’). Results indicated cultivar had a significant effect on all studied traits. ‘Option-500’ and ‘Hyola-401’ cultivars had the highest seed yield, protein content, and N:S ratio in seed. The levels of 150 and 220 kg N ha?1 resulted in the maximum protein content. Increasing N levels resulted in N content and decreased the oil content. The interaction effect between S and N levels showed the highest N content in seed was obtained with 300 kg S ha?1 and 225 kg N ha?1. 相似文献
5.
Mahdieh Hajghani Seyed Ali Mohammad Modarres Sanavy Hormazd Naghavi 《Archives of Agronomy and Soil Science》2013,59(12):1717-1730
Application of organic fertilizers in sustainable agriculture systems improves yield sustainability of field crop production. The current research has been formed to investigate the effects of various levels of vermicompost (zero, 3, 6 and 9 t ha?1) in combination with foliar spraying of potassium humate (0, 1, 2 and 3 mL L?1) on spring safflower, in Iran during 2012–2013. In addition, inorganic fertilization has been considered as conventional agriculture (CA). In the current experiment, growth indices, seed yield, yield components and flower yield were evaluated. The results showed that the maximum leaf area index, total dry weight and crop growth rate have been determined at 9 t ha?1 vermicompost and 3 mL L?1 K-humate while the maximum netto assimilation rate has existed in CA at the emergence of flower buds. Likewise, the results indicated that vermicompost leads to a significant increase in seed yield, flower yield and yield components except 1000 seed weight. Flower yield, head number per plant and seed number per head were affected by K-humate concentrations and increased significantly from 1 to 3 mL L?1. It should be mentioned that 9 t ha?1 vermicompost and 3 mL L?1 K-humate produced the highest seed and flower yield. 相似文献
6.
为了研究植物内源褪黑素与植物抗性的关系,以4叶1心的番茄幼苗为试验材料,采用酶联免疫吸附测定(ELISA)法测定正常番茄、鱼腥草提取液和灰霉菌侵染后的番茄茎叶中的褪黑素含量。结果表明:番茄叶片和茎的褪黑素含量分别为14.53、2.80 ng/g,二者之间差异极显著,叶片的褪黑素含量是茎的5.19倍;经鱼腥草提取液预处理和灰霉菌侵染后,番茄叶片的褪黑素含量显著增加,鱼腥草提取液预处理有助于减轻番茄叶片上的灰霉病发病症状,但并不依赖于叶片内源褪黑素含量的增加。可以检出的番茄茎叶中的褪黑素含量高于2.60 ng/g,就灵敏度而言,ELISA法完全可以用来检测番茄的组织器官的褪黑素含量。 相似文献
7.
Amin Setyo Leksono Kenta Takada Nobukazu Nakagoshi Koji Nakamura 《Journal of Forest Research》2006,11(1):61-64
A continuous sampling of canopy beetles was carried out to determine variations in the abundance, species diversity, richness,
and composition of the Mordellidae and Cerambycidae in a coppice woodland. Changes in the abundance and the species richness
were monitored at three heights in the forest throughout the season in 1999, using yellow and blue water pan traps. The results
showed significant variations in the abundance of Mordellidae among the canopy layers, while little variation was found for
Cerambycidae. The abundance, species diversity, and richness were generally greater in summer. The results showed distinct
species compositions in both families among layers. 相似文献
8.
Jezie A. Acorda DVM Magr Haruo Yamada DVM DVSc Seyed Mehdi Ghamsari DVM 《Veterinary radiology & ultrasound》1994,35(3):196-200
Ultrasonography of the liver was performed in 200 Holstein-Friesian dairy cattle using a 3.5 MHz transducer with a linear array electronic scanner. Liver samples were taken, processed and examined microscopically and the fat occupying rate was calculated. The hepatic ultrasonograms were evaluated according to the presence of bright pattern, dark pattern, deep attenuation, vascular blurring and blurring of edges. Of the 200 animals, 96 had a normal liver, 63 had hydropic degeneration of the liver, 37 had fatty infiltration of the liver, 3 had liver dystrophy and I had hepatic amyloidosis, diagnosed through histopathological examination. Amyloidosis was characterized by bright pattern and blurring of edges. Liver dystrophy had higher percentages of bright pattern and blurring of edges than normal liver. Hydropic degeneration had higher percentages of dark pattern and blurring of edges than normal liver. Fatty infiltration had higher percentages of bright pattern, deep attenuation, vascular blurring and blurring of edges than normal liver. The present results suggest that different ultrasonographic patterns can be observed in various diffuse hepatocellular disorders in dairy cattle 相似文献
9.
未尽利用热带水果,即在当地消费和医用的非贸易热带水果,未普及化,生长于野外,季节性强,但富含多酚类化合物、类胡萝卜素、花青素、脂肪酸、矿物质和氨基酸,因而具有一定的开发潜力。在马来西亚,热带水果丰富多样,主要有普通水果、观赏水果、特有水果、野生水果和高地水果,但大部分水果都未能充分利用,其中,典型的有罗望子、巴杖果、砂拉越芒果、钮扣山竹、榴莲、莲雾、挂尼芒果、野红毛丹和蛇皮果。这些水果可以分为3个类型:具有贸易开发潜力的主要包括无花果(Ficus sp.)、罗望子(Garcinia atroviridis)、尖必达(Artocarpus integer)、鲜花木果(Lepisan-thes alata)、野榴莲(Durio sp.)、橄榄木(Spondias cytherea)、菠萝蜜(Artocarpus heterophullus)、槟榔(Areca catechu)、野红毛丹(Nephelium ramboutan-ake)、蛇皮果(Salacca zalacca)和面包果(Artocarpus altilis);具有适于当地人们利用潜力的水果种类包括木胡瓜(Averrhoe bilimbi)、榔拜果(Baccaurea motteyana)、单贝果Baccaurea macrocarpa)、喃喃果属(Cynometra cauliflora)、西柚(Dialum indum)、黄肉榴莲(Durio kutejensis)、野生山竹(Garcinia hombroiniana)、野檬果(Garcinia parvifolia)、巴杖果(Mangifera feotida)、醋栗(Phyllanthus emblica)、蒲桃(Syzygium jambos);不具有经济利用开发潜力的水果种类包括哥露比(Salacca conferta)、青枣(Zizyphus mauritiana)、木奶果属(Baccaurea polyneura)、野檬果(Garcinia parvifolia)、番龙眼(Pometia sp.)、赤才果(Leppisanthes rubiginosa)、波漆果(Bouea microphylla)、蛋黄果(Pouteria campechiana)和仙都果(Sandoricum koetjape)。目前,有关未尽利用水果研究仍处于初期阶段,有必要使这些水果更为普及并得到有效利用,因此,政府和私人组织须采取一些措施以促进这些水果的消费。今后需对这些水果的营养成分、抗氧化作用以及疗效进行深入研究。 相似文献
10.