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71.
Formulations containing citrus polymethoxylated flavones (PMFs), mainly tangeretin, or citrus flavanone glucosides, hesperidin and naringin, were evaluated for cholesterol-lowering potential in hamsters with diet-induced hypercholesterolemia. PMF metabolites were also investigated. Diets containing 1% PMFs significantly reduced serum total and very low-density lipoprotein (VLDL) + LDL cholesterol (by 19-27 and 32-40%, respectively) and either reduced or tended to reduce serum triacylglycerols. Comparable reductions were achieved by feeding a 3% mixture of hesperidin and naringin (1:1, w/w), implying lower hypolipidemic potency of the hesperidin/naringin vs PMFs. HPLC-MS analysis identified high serum, liver, and urine concentrations of tangeretin metabolites including dihydroxytrimethoxyflavone and monohydroxytetramethoxyflavone glucuronides and aglycones. Total liver concentrations of tangeretin derivatives corresponded to hypolipidemic concentrations of intact tangeretin in earlier experiments in vitro. This suggests that PMFs are novel flavonoids with cholesterol- and triacylglycerol-lowering potential and that elevated levels of PMF metabolites in the liver might be directly responsible for their hypolipidemic effects in vivo.  相似文献   
72.
Of 12 pregnant swine (vaccinates) given a 4-pilus enterotoxigenic E coli (ETEC) bacterin (K88, K99, 987P, F41), all developed comparable or significantly higher serum and colostral antibody levels than those of 8 pregnant swine (controls) given a 3-pilus ETEC bacterin (K88, K99, 987P). When piglets were challenged with an ETEC strain bearing the F41 antigen, those from vaccinates had significantly lower mortality, less scours, less severe clinical signs and better weight gain than those from controls.  相似文献   
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蛋氨酸在家禽生产过程中极为重要,因此家禽业也成为了决定蛋氨酸未来的关键性行业。在未来家禽业特别是肉鸡生产方面,虽然鸡肉产量的增长率正在下降,但其绝对增量仍很稳定,因此与.其他肉类相比,鸡肉仍具有其很强的竞争力。在过去20年里,全球鸡肉产量以年平均200万吨的速度增长,并且在未来的10年甚至20年中,将会以相同的速度持续增长。  相似文献   
75.
拉丁美洲地区家禽业近年来实现了一段时间的持续强劲增长,该地区行业领袖们如何看待家禽生产的未来发展?他们的愿景是什么?  相似文献   
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Binucleate Rhizoctonia (BNR) spp. isolates were collected from taro (Colocasia esculenta (L.) Schott) and ginger (Zingiber officinale (Willd.) Roscoe) (Yunnanxiaojiang cv.) in Yunnan province. These Yunnan (YN) isolates did not anastomose with any of the tester isolates of the known AGs of binucleate Rhizoctonia spp. The growth of YN cultures on PDA was appressed, mealy and matlike after 4 days of incubation, then turned white brown, producing brown to dark brown, irregularly shaped sclerotia were embedded in the PDA medium after 14 days. All attempts to induce basidiospore production were unsuccessful, but the length and sequence of the internal transcribed spacer (ITS1 + 5.8S rDNA + ITS2) regions of 5.8S rDNA from the YN isolates were identical in length and sequence to isolates of all the other AGs of binucleate Rhizoctonia /Ceratobasidium spp. The sequences of 5.8S rDNA-ITS from the YN isolates were unique among AGs of BNR. The YN isolates had sequence similarities of 94% with isolates of AG Fb and P, 93% with AG E, 91% with AG R, 79–94% with AG S, and 74–87% with AG A, Ba, Bb, Bo, C, DI, DII, DIII, Fa, G, H, I, K, L, O, and Q. Four isolates of AG YN caused minor virulence (lesions ≦1mm2) to ginger or taro in growth chamber studies. It was concluded that the YN isolates belong to a new anastomosis group AG-V of the Ceratobasidium spp..  相似文献   
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棉胚珠继代培养纤维体系的建立   总被引:5,自引:0,他引:5  
针对传统的棉胚珠培养方法因纤维在发育中途夭亡而不能用于研究次生壁增厚和强度形成的机理,本文建立了棉胚珠继代培养纤维体系,即根据花铃的形态特征选取Ⅱ类发育状态的胚珠作外植体,以14d为周期连续3次继代,在继代培养基中添加5g*L-1活性碳,并根据纤维发育不同阶段的特点调整植物生长物质的种类和浓度.结果使纤维重现了植株  相似文献   
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