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251.
Different central manifestations in response to electroacupuncture at analgesic and nonanalgesic acupoints in rats: a manganese-enhanced functional magnetic resonance imaging study 总被引:6,自引:0,他引:6
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Jen-Hwey Chiu Mao-Shu Chung Hui-Cheng Cheng Tzu-Cheng Yeh Jen-Chuen Hsieh Chung-Yen Chang Wan-Yo Kuo Henrich Cheng Low-Tone Ho 《Canadian journal of veterinary research》2003,67(2):94-101
Acupuncture analgesia is an important issue in veterinary medicine. This study was designed to elucidate central modulation effects in response to electroacupuncture (EA) at different acupoints. Manganese-enhanced functional magnetic resonance imaging was performed in Sprague-Dawley rats after sham acupuncture, sham EA, or true EA at somatic acupoints. The acupoints were divided into 3 groups: group 1, analgesic acupoints commonly used for pain relief, such as Hegu (LI 4); group 2, nonanalgesic acupoints rarely used for analgesic effect, such as Neiguan (PC 6); and group 3, acupoints occasionally used for analgesia, such as Zusanli (ST 36). Image acquisition was performed on a 1.5-T superconductive clinical scanner with a circular polarized extremity coil. The results showed that there was no neural activation caused by EA at a true acupoint with shallow needling and no electric current (sham acupuncture). When EA at a true acupoint was applied with true needling but no electric current (sham EA), there was only a slight increase in brain activity at the hypothalamus; when EA was applied at a true acupoint with true needling and an electric current (true EA), the primary response at the hypothalamus was enhanced. Also, there was a tendency for the early activation of pain-modulation areas to be prominent after EA at analgesic acupoints as compared with nonanalgesic acupoints. In conclusion, understanding the linkage between peripheral acupoint stimulation and central neural pathways provides not only an evidence-based approach for veterinary acupuncture but also a useful guide for clinical applications of acupuncture. 相似文献
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β-Glucanase activity interferes with molecular characterization of mixed-linkage (1→3)(1→4)-β-d -glucans (β-glucans). Reductions in β-glucanase activity were determined after barley cvs. Azhul, Waxbar, and Baronesse were treated with autoclaving (120°C, 45 min), calcium chloride (0.05M, 1 hr), 70% ethanol (80°C, 4 hr), hydrochloric acid (0.1N, 1 hr), oven heating (120 and 140°C, 40 min), sodium hydroxide (0.0025M, 1 hr), and 5% trichloroacetic acid (TCA) (40°C, 1 hr). High-performance size-exclusion chromatography (HPSEC) of α-amylase-treated aqueous extracts was used to demonstrate the effects of treatments on the molecular weights of β-glucans. The HPSEC system included multiple-angle, laser light scattering, refractive index, and fluorescence detectors. β-Glucanase activities, ranging from 52 to 65 U/kg of barley, were reduced by autoclaving (50–75%), hot alcohol (67–76%), oven heating (40–96%), CaCl2 (75–95%), NaOH (76–89%), and TCA (92–96%). Some malt β-glucanase activity remained after most treatments. HCl and TCA treatments reduced extraction and molecular weights of β-glucans. Weight-average molecular weights (Mw) for β-glucans extracted with water at 23°C were low (most <8 × 105). Base treatment (pH 9) and extraction at 100°C for 2.5 hr resulted in the greatest extraction of β-glucans and highest Mw. As a result, the conditions seem appropriate for measurement of physical characteristics of β-glucans in cereal products. 相似文献
255.
引种印楝国产种子的印楝素含量及杀虫活性初步研究 总被引:27,自引:2,他引:27
应用高效液相色谱法(HPLC)定量分析结果表明,从海南省种植的印楝树(Azodirochta indica A.Juss)上收获的种子中印楝素(Azadirachtin)含量为0.48%,甲醇提取物获得率为16.395,其中含印楝素2.95,国产印楝种子提取物对亚洲玉米螟(Ostrinia furnccalis)和小菜蛾(Ptutella xylostella)幼虫均有强烈的抑制生长发育作用活性,提取物馏分F3-5(含印楝素0.883%)500ppm饲喂亚洲玉米螟4-5龄幼虫造成100%畸形死亡和变成“永久性幼虫”,113ppm时也有显著效果,2%处理小菜蛾四龄幼虫也使之100%畸形死亡,试验还发现不含印楝素的其它馏分对上两种害虫也有不同程度的作用效果,值得进一步研究。 相似文献
256.
The use of the Rapid Visco Analyser (RVA) for application in the screening of wheat breeding lines for starch quality and potential noodle quality has been limited by relatively low sample throughput. Current methods generally enable only 20–30 samples to be tested each day. This study sought to develop a more rapid time‐temperature profile that could be applied to whole meal samples. A profile that involved a total analysis time of 7.5 min/sample gave measurements of peak viscosity (PV) and breakdown (BD) on whole meal that were highly correlated with corresponding measurements obtained using a more conventional profile that had been applied to low‐extraction flours. BD and PV were also highly correlated with the total texture score of ramen (Chinese‐style alkaline noodles as manufactured in Japan), but only when 1 mM AgNO3 was used to eliminate the effects of α‐amylase. 相似文献