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排序方式: 共有298条查询结果,搜索用时 46 毫秒
1.
Lucas C. Maltez Luis A. L. Barbas Marcelo H. Okamoto Diogo L. de Alcantara Lopes Luis A. Romano Luís A. Sampaio Luciano Garcia 《Journal of the World Aquaculture Society》2019,50(2):346-358
This study investigated the secondary stress responses of Paralichthys orbignyanus exposed to ammonia and nitrite and after recovery. Fish were exposed to 0.12, 0.28, and 0.57 mg NH3‐N/L, or 5.72, 10.43, and 15.27 mg NO2‐N/L for 10 d followed by the same time length for recovery. Ammonia‐ and nitrite‐free water was used as a control treatment. Blood samples were collected after 1, 5, and 10 d of exposure and after recovery. Fish exposed to ammonia presented lower and higher glucose levels after 10 d of exposure and recovery, respectively. Ammonia induced initial and transient ionic disturbances and metabolic alkalosis. Nitrite exposure caused hyperglycemia, increased plasma K+ levels, and respiratory alkalosis, whereas metabolic acidosis was observed after recovery. Increased proportion of monocytes and/or granulocytes and reduced number of lymphocytes were demonstrated in fish exposed to 0.28 mg NH3‐N/L (Day 1) and 10.43 mg NO2‐N/L (Day 5) and after recovery in the 0.28 and 0.57 mg NH3‐N/L treatments. Exposure to ammonia decreased the proportion of granulocytes on Day 5. In conclusion, exposure to concentrations at 0.12 mg NH3‐N/L and 5.72 mg NO2‐N/L provoked physiological disorders in Brazilian flounder. Nonetheless, fish exposed to 5.72 mg NO2‐N/L following a 10‐d recovery period showed complete resumption of homeostasis. 相似文献
2.
Rashmi Kumari Hirokazu Ito Masahiro Takatani Miho Uchiyama Tadashi Okamoto 《Journal of Wood Science》2007,53(6):470-480
Although wood/cellulose-plastic composites (WPC) of low wood/cellulose content have been more accepted worldwide and are promoted
as low-maintenance, high-durability building products, composites containing high wood/cellulose content are not yet developed
on an industrial scale. In this study, flow properties, mechanical properties, and water absorption properties of the compounds
of cellulose microfiber/polypropylene (PP) and maleic anhydride-grafted polypropylene (MAPP) were investigated to understand
effects of the high cellulose content and the dimensions of the cellulose microfiber. The molding processes studied included
compression, injection, and extrusion. It was found that fluidity is not only dependent on resin content but also on the dimension
of the filler; fluidity of the compound declined with increased fiber length with the same resin content. Dispersion of the
composite was monitored by charge-coupled device (CCD) microscope. Increasing the plastic content in the cellulose-plastic
formulation improved the strength of mold in addition to the bond development between resin and filler, and the tangle of
fibers. The processing mode affected the physicomechanical properties of the cellulosic plastic. Compression-molded samples
exhibited the lowest modulus of rupture (MOR) and modulus of elasticity (MOE) and the highest water absorption, while samples
that were injection-molded exhibited the highest MOR (70 MPa) and MOE (7 GPa) and low water absorption (2%). 相似文献
3.
4.
Kato A Higuchi Y Goto H Kizu H Okamoto T Asano N Hollinshead J Nash RJ Adachi I 《Journal of agricultural and food chemistry》2006,54(18):6640-6644
Ginger (Zingiber officinale Roscoe) continues to be used as an important cooking spice and herbal medicine around the world. Scientific research has gradually verified the antidiabetic effects of ginger. Especially gingerols, which are the major components of ginger, are known to improve diabetes including the effect of enhancement against insulin-sensitivity. Aldose reductase inhibitors have considerable potential for the treatment of diabetes, without increased risk of hypoglycemia. The assay for aldose reductase inhibitors in ginger led to the isolation of five active compounds including 2-(4-hydroxy-3-methoxyphenyl)ethanol (2) and 2-(4-hydroxy-3-methoxyphenyl)ethanoic acid (3). Compounds 2 and 3 were good inhibitors of recombinant human aldose reductase, with IC50 values of 19.2 +/- 1.9 and 18.5 +/- 1.1 microM, respectively. Furthermore, these compounds significantly suppressed not only sorbitol accumulation in human erythrocytes but also lens galactitol accumulation in 30% of galactose-fed cataract rat model. A structure-activity relationship study revealed that the applicable side alkyl chain length and the presence of a C3 OCH3 group in the aromatic ring are essential features for enzyme recognition and binding. These results suggested that it would contribute to the protection against or improvement of diabetic complications for a dietary supplement of ginger or its extract containing aldose reductase inhibitors. 相似文献
5.
Kawabata J Okamoto Y Kodama A Makimoto T Kasai T 《Journal of agricultural and food chemistry》2002,50(19):5468-5471
DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging reactions of protocatechuic and gallic acids, and their methyl esters, have been investigated by NMR. In acetone, methyl protocatechuate was gradually converted to a Diels-Alder adduct of two molecules of the intermediate quinone in the reaction with DPPH radical, whereas methyl gallate rapidly gave a symmetrical dimer via a putative quinone precursor. Both dimers are rather unstable and their structures have been deduced by in situ NMR measurements of the reaction mixtures. Gallic acid also gave a corresponding symmetrical dimer in the same reaction as methyl gallate, although protocatechuquinone produced from protocatechuic acid did not yield a Diels-Alder adduct, unlike its methyl ester. Interestingly, these dimer formations were not observed in methanol solution. 相似文献
6.
Nakamura Y Suganuma E Matsuo T Okamoto S Sato K Ohtsuki K 《Journal of agricultural and food chemistry》1999,47(2):544-549
Fushimi sweet pepper, "Fushimi-togarashi", is one of the "Kyo-yasai", traditional vegetables, in Kyoto, Japan. The chloroform fraction of Fushimi sweet pepper showed bioantimutagenicity on UV induced mutation in Escherichia coli B/r WP2. The bioantimutagen was purified with silica gel chromatography and identified as 2, 4-nonadienal (ID(50) = 20 microg/plate) on the basis of GC retention time and EI-MS spectrum of authentic 2,4-nonadienal. The sweet pepper also contained a known bioantimutagen, benzaldehyde (ID(50) = 2 mg/plate). Additive bioantimutagenicity was also observed by 2, 4-nonadienal with benzaldehyde. 2,4-Nonadienal did not show bioantimutagenicity in an UV excision repair deficient strain, E. coli B/r WP2s uvrA(-)(). Furthermore no delay of the first cell division after UV irradiation was observed in E. coli B/r WP2. These results indicate that the bioantimutagenic activity of 2, 4-nonadienal on UV mutagenesis might depend on the excision repair system in E. coli B/r WP2. 相似文献
7.
Su Lai Yee Mon Moe Lwin Aye Aye Maw Lat Lat Htun Saw Bawm Kotaro Kawabe Yasuhiko Wada Shin Okamoto Takeshi Shimogiri 《Animal Science Journal》2021,92(1):e13647
Myanmar indigenous chickens play important roles in food, entertainment, and farm business for the people of Myanmar. In this study, complete mitochondrial D-loop sequences (1232 bp) were analyzed using 176 chickens, including three indigenous breeds, two fighting cock populations, and three indigenous populations to elucidate genetic diversity and accomplish a phylogenetic analysis of Myanmar indigenous chickens. The average haplotype and nucleotide diversities were 0.948 ± 0.009 and 0.00814 ± 0.00024, respectively, exhibiting high genetic diversity of Myanmar indigenous chickens. Sixty-four haplotypes were classified as seven haplogroups, with the majority being haplogroup F. The breeds and populations except Inbinwa had multiple maternal haplogroups, suggesting that they experienced no recent purifying selection and bottleneck events. All breeds and populations examined shared haplogroup F. When 232 sequences belonging to haplogroup F (79 from Myanmar and 153 deposited sequences from other Asian countries/region) were analyzed together, the highest genetic diversity was observed in Myanmar indigenous chickens. Furthermore, Myanmar indigenous chickens and red junglefowls were observed in the center of the star-like median-joining network of 37 F-haplotypes, suggesting that Myanmar is one of the origins of haplogroup F. These findings revealed the unique genetic characteristic of Myanmar indigenous chickens as important genetic resources. 相似文献
8.
Edgar C Amar Viswanath Kiron Shuichi Satoh Nobuaki Okamoto and Takeshi Watanabe 《Fisheries Science》2000,66(6):1068-1075
SUMMARY: We attempt to assess the impact of different levels of dietary β-carotene on immune function in rainbow trout. Semi-purified diets containing 0, 40, 200, and 400 mg β-carotene/kg dry diet were fed for 12 weeks to fish with average weight of 45 g. In addition to the humoral and cellular immune parameters, growth and feed utilization were examined. There were no marked differences in growth and feed utilization showing that β-carotene was not particularly efficient in enhancing growth of rainbow trout. Of the immune parameters measured, total immunoglobulin was significantly highest for the 200 mg β-carotene fed group. Serum complement activity (alternate pathway) at 200 and 400 mg β-carotene supplementation was significantly higher than that of the unsupplemented group. An increasing trend in lysozyme activity was observed, however, the differences among the groups were not significant. Phagocytic activity was similar among diet groups except at the highest level of supplementation where it was the maximum. Oxygen radical production by peripheral blood leukocytes appeared to be lower at higher levels of carotenoid supplementation. Overall, dietary β-carotene clearly enhanced immune response parameters in rainbow trout such as serum complement activity and total plasma immunoglobulin but did not show a definite influence for the other factors examined in the present study. 相似文献
9.
Aonidiella aurantii (Mask.) which was accidentally introduced in Sicily in 1968 has since become a dangerous pest requesting special treatments in citrus groves. Experiments have been carried out on Citrus lemon to evaluate the efficacy of several organophosphorous compounds partly in mixture with white oil and this latter applied sole (cf. table 1). The results obtained against young females are set out in table 2; they show excellent results with almost all compounds whereas the same pesticides had a rather poor effect on mature females (cf. table 3).
It is concluded that the replacement of white oils by organophosphorous compounds is not justified providing that the control is directed against larvae and young females. This means that a proper timing is essential to obtain a satisfactory mortality, thus avoiding the use of detrimental broad acting pesticides. 相似文献
It is concluded that the replacement of white oils by organophosphorous compounds is not justified providing that the control is directed against larvae and young females. This means that a proper timing is essential to obtain a satisfactory mortality, thus avoiding the use of detrimental broad acting pesticides. 相似文献
10.
将18头荷斯坦产奶牛随机分为试验6组,每组3头,试验Ⅰ~Ⅵ组奶牛依次饲喂不同精粗料比(精料:粗料)的TMR1(20∶80)、TMR2(30∶70)、TMR3(40∶60)、TMR4(50∶50)、TMR5(60∶40)、TMR6(70∶30)的日粮,探讨不同精粗料比TMR对奶牛粪尿、N、P的排泄量和CH4释放量的影响。结果,饲喂TMR4与饲喂TMR1和TMR6的奶牛相比,每头奶牛每年CH4释放量减少15.20Kg和89.84Kg;粪便排泄量减少1.37t和1.41t;N降低3.71kg和17.50kg;P减少2.59kg和4.07kg,比TMR1FCM提高10.54%(P〈0.05);乳脂率增加9.67%(P〈0.05);乳糖增加7.26%(P〈0.05),能减少奶牛对土壤水源及空气的污染,提高奶牛的生态效益和经济效益。 相似文献