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181.
Kim HJ Suh HJ Kim JH Park S Joo YC Kim JS 《Journal of agricultural and food chemistry》2010,58(22):11633-11638
The extract of soybean exposed to biotic elicitors such as food-grade fungus is known to have antioxidant activity. Glyceollins were major bioactive compounds present in soybean elicited by fungi and shown to have antifungal and anticancer activities. The purpose of present study was to evaluate the antioxidant activities of glyceollins by measuring ferric reducing antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, singlet oxygen quenching, 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging, hydroxyl radical scavenging activity, and lipid peroxidation inhibition. In addition, the antioxidant potential of glyceollins were measured by a fluorescent probe, 2',7'-dichlorofluorescin diacetate (DCFDA), and dihydroethidium (DHE) in mouse hepatoma hepa1c1c7 cells in which they were insulted with H2O2 to generate reactive oxygen species (ROS). Glyceollins showed a strong reducing power and inhibited lipid peroxidation, with significant scavenging activities of radicals including singlet oxygen, superoxide anion, ABTS, and DPPH. We also found that glyceollins significantly suppressed H2O2-induced ROS production in hepa1c1c7 cells. Therefore, glyceollins deserve further study as natural antioxidants and nutraceuticals. 相似文献
182.
Rakib MA Kim YS Jang WJ Choi BD Kim JO Kong IK Ha YL 《Journal of agricultural and food chemistry》2010,58(22):12022-12030
The protective effect of c9,t11-conjugated linoleic acid (CLA) on the inhibition of gap junctional intercellular communication (GJIC) was examined in a human mammary epithelial cell line (MCF-10A) treated with 12-O-tetradecanoylphorbol-13-acetate (TPA), relative to t10,c12-CLA isomer. TPA inhibited GJIC in a dose-dependent and reversible manner and was associated with connexin 43 phosphorylation. Pretreatment of 20 μM c9,t11-CLA for 24 h prior to 60 nM TPA for 1 h prevented the inhibition of GJIC by reducing the phosphorylation of connexin 43 via suppressing extracellular signal-regulated kinases (ERK1/2) activation. Reactive oxygen species (ROS) accumulation by TPA was attenuated by c9,t11-CLA. The efficacy of c9,t11-CLA in protecting inhibition of GJIC, connexin 43 phosphorylation, and ROS production was superior to that of t10,c12-CLA. These results suggest that c9,t11-CLA, including t10,c12-CLA, prevents the carcinogenesis of MCF-10A cells by protecting down-regulation of GJIC during the cancer promotion stage, and lack of their toxicities could be an excellent indicator for the chemoprevention of breast cancer. 相似文献
183.
Chung Yeon Hwang Soonwook Jung Y. S. Hwang Byung Cheol Cho 《Water, air, and soil pollution》2010,213(1-4):161-169
Ballast seawater is considered globally as a major vector for invasions of non-indigenous organisms. Several technologies have been tested for their ability to remove organisms from ballast water. In the present study, we constructed a novel pulsed high-voltage discharge (PHVD) system that could operate in either high current mode with several hundred amperes or shockwave generating mode with relatively lower current in seawater. In laboratory-scale experiments, the PHVD system with shockwave-generating mode was found to be more effective in killing zooplankton (1.9- to 4.0-fold) and phytoplankton (3.3-fold) than high current mode at discharge with 300–500 pulses at 7.1 kV. Further experiments were carried out at different voltages and pulse-numbers to examine effects of the shockwave-generating PHVD system on viabilities of one zooplankton larva, two phytoplankton species, and an indicator bacterium suspended in seawater in a static chamber. For zooplankton, live cells were not detected at discharge with 400 pulses at 13 kV. For phytoplankton, the initial live cells of a dinoflagellate was decreased by 77?±?0.5%, and the initial chl a concentration of a diatom was decreased by 76?±?6% at discharge with 700 pulses at 13 kV. For an indicator bacterium Escherichia coli, live cells were not detected at discharges with 200 or 700 pulses at 13 kV. Measurements of ATP content of organisms showed congruent results with those obtained by the above methods, suggesting it may be a rapid method for evaluating treatment efficiency. Though further scale-up studies are necessary, these results suggest that the PHVD system have a high potential for applying to ballast seawater treatment. 相似文献
184.
185.
Use of ultrasonic Doppler waveforms to estimate changes in uterine artery blood flow and vessel compliance 总被引:2,自引:0,他引:2
Previous data from our laboratory have demonstrated that uterine blood flow (UBF) and uterine arterial smooth muscle tone vary regularly during the estrous cycle of the cow. Uterine blood flow is highest and uterine arterial tone is lowest at estrus, whereas UBF is lowest and uterine arterial tone is highest during the luteal phase of the cycle. Blood flow through arteries is highly pulsatile; changes in arterial wall properties affect shape of the velocity waveform. This study was conducted to evaluate changes in uterine arterial velocity waveforms throughout the estrous cycle of the cow and to relate these changes to fluctuations in UBF and concentrations of estrogen and(or) progesterone in systemic blood. Pulsatile velocity waveforms were obtained daily from pulsed-wave ultrasonic probes placed surgically on the middle uterine artery of five beef cows exhibiting estrous cycles of normal duration (d 0 = day of estrus). Velocity waveforms varied regularly during the estrous cycle of each cow in association with changes in UBF and steroid concentrations. Further, two distinct velocity waveform shapes were observed during the estrous cycle. The first waveform shape, which was observed during periods of high UBF (d -4 to +4 of the estrous cycle), was characteristic of a highly compliant vessel and was associated with a high estrogen:progesterone ratio. The second waveform shape, which was observed from d 7 to 14 of the estrous cycle, was characteristic of a less compliant vessel and was associated with a depressed estrogen:progesterone ratio. These data suggest that compliance of the uterine artery changes during the estrous cycle in association with the changing estrogen:progesterone ratio in blood. 相似文献
186.
Two trials were conducted to determine the NE value of ensiled wet corn gluten feed (WCGF) in corn silage finishing diets for beef cattle. In Trial 1, 96 Angus-crossbred yearling steers were fed corn silage-based diets containing 0, 20, 40, or 60% ensiled WCGF. Increased dietary WCGF resulted in improved DMI (linear, P less than .05), ADG (linear; P less than .05), and feed/gain (linear, P less than .05). Levels of WCGF had no (P greater than .05) effect on fat thickness, marbling, quality grade, carcass protein, and carcass fat. In Trial 2, four Angus-crossbred yearling steers were used in a 4 x 4 Latin square design to determine the effect of feeding 0, 20, 40, or 60% WCGF on DE and ME values. Level of WCGF had no (P greater than .05) effect on dietary DE and ME values. Regression equations were developed for predicting NEm (Y = 1.51 + .0009X; R2 = .22) and NEg (Y = 1.04 + .0028X; R2 = .35) in which Y = predicted diet NE values in megacalories/kilogram and X = percentage of dietary WCGF. The NEg value increased .06 Mcal/kg for each 20% increase in WCGF. Predicted NEm and NEg values for WCGF are 1.60 and 1.32 Mcal/kg, respectively. 相似文献
187.
The non-depolarising muscle relaxant vecuronium bromide was administered to 20 dogs undergoing a variety of surgical procedures under general anaesthesia. An initial dose of 0–1 mg/kg was administered and followed by an infusion of 0–1 mg/kg/hour. Reversal of the neuromuscular block was carried out with neostigmine and atropine. 相似文献
188.
J B Madison D Young D Richardson 《Journal of the American Veterinary Medical Association》1991,198(3):455-456
Shoulder luxation in a 3-year-old Thoroughbred filly was treated by closed reduction, using a calf jack to provide traction on the limb. Arthroscopic examination of the shoulder allowed removal of soft tissue and bony debris. After surgery, the filly was confined to a box stall for 6 months. Eight months after surgery, the filly was doing light work and was not lame. Muscular atrophy present before surgery had resolved. Use of a calf jack may allow reduction of shoulder luxation under field conditions. 相似文献
189.
1. In experiment 1, growing conventional (CV) chicks were fed on diets containing graded amounts (0, 100, 200 and 300 g/kg diet) of sorbose from 4 to 14 d. Protein, fat and energy deposition were determined after carcase analysis. The values for growth, food efficiency, metabolisable energy (ME) and fat and energy depositions declined as the dietary sorbose content increased. 2. In experiment 2, the performances of germ-free (GF) and CV chicks fed on diets with (100 g sorbose/kg diet) or without sorbose were investigated. On both diets, body weight gain, food consumption and protein accumulation in GF chicks were significantly higher than those in CV birds. No significant differences were observed between the dietary treatment except for ME values, which were significantly lower for the sorbose diet. 3. It is suggested that dietary sorbose decreased energy utilisation, and that the microbial contribution to the utilisation of dietary sorbose was negligible in the chicken. 相似文献
190.