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Effects of feeding alkaline hydrogen peroxide-treated wheat straw-based diets on digestion and production by dairy cows 总被引:1,自引:0,他引:1
M G Cameron G C Fahey J H Clark N R Merchen L L Berger 《Journal of dairy science》1990,73(12):3544-3554
Twelve Holstein cows, averaging 34 d postpartum, were used in three replications of a 4 x 4 Latin square design to determine the effects of feeding different levels of alkaline hydrogen peroxide-treated wheat straw on digestion and production responses in lactating dairy cows. Complete mixed diets consisted of 50% concentrate (DM basis) plus varying proportions of treated wheat straw, alfalfa haylage, and corn silage as the forage source. Treatment contained 0 (control), 12.5 (low), 25.0 (medium), or 37.5% (high) treated wheat straw in the diet. Dry matter intakes were 18.5, 17.2, 17.4, and 16.7 kg/d for the four treatments, respectively. Apparent digestibilities of DM and OM were decreased (approximately 4.4 percentage units), and NDF and ADF digestibilities were increased by 9.4 and 3.0 percentage units, respectively, with the high wheat straw diet. Yields of milk and 4% FCM, and SNF percentage did not differ among the treatment groups. Milk fat percentage increased (from 3.07 to 3.32%) and milk protein percentage decreased (from 2.61 to 2.56%) as the proportion of treated wheat straw increased in the diet. Cows fed the higher proportions of treated wheat straw had increased ruminal concentrations of total VFA and molar percentage acetate but a decreased molar percentage propionate, resulting in a greater acetate to propionate ratio. Cows fed the low and medium wheat straw diets had slightly lower DM intakes but production responses were similar to cows fed the control diet containing alfalfa haylage and corn silage as fiber sources. 相似文献
674.
This study explored the efficacy of hepatic arterial therapy, comparing both injection and infusion of 5-fluorouracil (5-FU) in prolonging the survival of 92 patients with recurrent unresectable hepatic metastasis from colorectal cancer. With respect to pretreatment carcinoembryonic antigen doubling time (CEA-DT), 56 patients were treated with intra-arterial injection, and 36 with intra-arterial infusion. In 21 patients with a CEA-DT of less than 40 days, the cumulative survival of patients treated with arterial injection was significantly longer than that of patients treated with arterial infusion. In 45 patients with a CEA-DT of 40-80 days, the survival curves of patients did not differ from each other. Of the remaining 26 patients with a CEA-DT of more than 80 days, those treated using arterial infusion had an excellent prognosis, in contrast to those treated using arterial injection, with statistical significance. CEA-DT may be useful when choosing a chemotherapy regimen, and may help to accurately establish the prognosis of patients with unresectable hepatic metastasis from colorectal cancer. 相似文献
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机器翻译系统及翻译工具的开发和使用 总被引:7,自引:0,他引:7
本文综述了当前计算机翻译软件的需求和应用情况,着重讨论了如何设计翻译系统使其质量能达到可出版水平, 其中包括开发受限语言翻译系统, 翻译工作站, 及软件本地化。同时本文还涉及到如何开发非传统概念的翻译软件,特别是针对Web页面和其它应用在Internet上各类信息的翻译软件。本文还讨论了机器翻译未来的需要以及正在开发的一些系统。文中最后一部分比较了一下通过人译、机译,机助人译的方式达到的几种最合适的翻译方法。 相似文献