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991.
上海湄潭烤烟基地烟叶主要化学成分分析与评价 总被引:1,自引:1,他引:0
以2003-2007年上海湄潭烤烟基地8个主产乡镇K326品种B2F、C3F、X2F等级、224份烟叶样品为材料,测定烟叶总植物碱、可溶性糖、还原糖、总氮、钾、氯含量,分析其特征及相关性、年度变异,并以卷烟工业企业烟叶原料质量评价体系标准进行评价.结果表明:上海湄潭烤烟基地烟叶主要化学成分含量较适宜、协调性较好;氯、钾和总植物碱含量变异大,还原糖、可溶性糖含量变异次之,总氮含量变异较小;C3F等级主要化学成分含量稳定性好于B2F和X2F;C3F和X2F等级主要化学成分含量及协调性符合上海卷烟工业烟叶原料质量评价体系指标要求,B2F等级总植物碱含量较高(均值4.25%). 相似文献
992.
B. LeRoy A. Painter H. Sheppard L. Popiolek M. Samuel-Foo T. M. Andacht 《Veterinary and comparative oncology》2007,5(2):119-130
Prostatic carcinoma is an important cancer in both men and dogs. Dogs have been a valuable animal model for investigating prostate cancer, but their relevance is unclear as the origin of canine prostatic carcinomas is unknown. We hypothesized that a proteomic approach for diagnosis of these neoplasms might provide quantitative data useful for more complete characterization of their origin. Protein expression profiles were prepared from normal canine prostate glands and bladders. The normal protein profiles were then compared with protein expression profiles of three canine prostatic carcinomas. Two‐dimensional differential in‐gel electrophoresis (2‐D DIGE) was used to analyse an average of approximately 1000 proteins per carcinoma. When compared with normal prostate tissue, the carcinomas exhibited greater than 2.5‐fold difference in expression for an average of 230 proteins. Similar proteomic comparisons between the carcinomas and the normal bladder revealed a greater than 2.5‐fold difference in expression for an average of 208 proteins. Mass spectrometry and protein database homology were used to identify nine proteins (α‐enolase, vimentin, GRP78, endoplasmin (GRP94), albumin, keratins 7 and 8, haptoglobin, and transferrin) overexpressed by the carcinomas. Statistical testing demonstrated that keratin 7, GRP78, and endoplasmin were significantly overexpressed in the carcinomas compared with normal prostate or bladder. Principal components analysis revealed that the carcinomas formed a unique cluster distinct from either the normal prostate or normal bladder. In conclusion, proteomic analysis revealed that whereas the majority of proteins expressed by canine prostatic carcinomas are also expressed by normal and neoplastic bladder and prostate tissue, the carcinomas contained unique protein components that allowed their segregation as a distinct group separate from normal canine prostate and bladder. Additionally, several proteins uniquely expressed by canine prostatic carcinomas were also identified. 相似文献
993.
从石榴叶的活性成分、功能活性以及开发利用三方面对石榴叶进行了综述,同时对目前石榴叶研究存在的问题进行了总结与展望,以期为石榴叶的进一步研究与开发提供参考。 相似文献
994.
P. Peltonen-Sainio 《Journal of Agronomy and Crop Science》1997,178(3):149-155
Contribution of leaf area duration (LAD) to grain yield during the short growing season characteristic of northern latitudes may differ from the marked impact it has at lower latitudes. Three experiments (exps) were carried out at Viikki Experimental Farm, University of Helsinki, Finland (60° 13′N) to compare associations between main shoot and tiller LAD with grain yield, yield components and morpho-physiological traits characterizing plant stand structure. This was done using correlation analysis and principal component analysis (PCA) for data from trials conducted during 1993–1995. Exp I included three N fertilizer rates (80, 120, 160 kg N ha?1), three seeding rates (250, 500, and 750 seeds m?2), and tall, moderate, semi-dwarf, and dwarf oat lines. Exp II incorporated two N fertilizer rates (80 and 120 kg ha?1), three seeding rates (400, 600, and 800 seeds m?2), and naked and hulled oat lines, and exp III, foliar applications of plant growth regulators [control, chlormequat chloride (CCC), and ethephon], and dwarf, naked, and conventional oat lines. LAD for main shoots and tillers [calculated as ∫ LAI d T, where T is cumulated degree days from seedling emergence to yellow ripening (dd °C)] and 12 morpho-physiological traits were measured. Oat was not able to benefit from high main shoot LAD if drought occurred at grain-fill, but in the absence of severe drought or if it occurred at pre-anthesis, high LAD favoured yield formation. Tiller LAD had a negative impact, if any, on grain yield in cases of an inverse relationship between tiller LAD and yield components on main shoots was recorded. Use of low seeding rates resulted in improved ability of total LAD to contribute to dry-matter production, but was not associated with grain yield. Low seeding rates enhanced formation of high tiller LAD, which was not able to compensate for grain yield reduction caused by fewer main shoots. Foliar application of CCC and ethephon tended to increase the proportion of LAD production by tillers at the expense of grain yield, which can be attributed to lower post-anthesis precipitation. Oat types differed in main shoot and tiller LAD. Disadvantageous characteristics of naked oat, such as low single groat weight, were not associated with insufficient main shoot LAD. High tiller LAD in naked lines and the Minnesota-adapted dwarf line that was not associated with high tiller grain yield in naked lines, in particular, indicates that tiller growth was enhanced at the expense of grain yield production. Application of N fertilizer at various rates did not have any effect on LAD. 相似文献
995.
几个早熟苹果品种香气成分的GC-MS分析 总被引:38,自引:5,他引:38
采用顶空固相微萃取和气相色谱质谱联用技术分析极早熟苹果新品种早丰甜及贝拉、辽伏等早熟苹果品种果实香气成分。结果表明,(1)3种早熟苹果含醇类等12类136种香气成分,其中1-己醇、(E)-2-己烯醛、乙酸丁酯、乙酸己酯等成分均在1%以上,总含量占测定芳香物质总量的93.81%,为参试苹果品种的主要香气成分;(2)β-大马酮及草蒿脑可能是早丰甜特有香气物质;(3)根据香气成分的种类及含量,可将早丰甜与贝拉分别划为“酯香型”与“醇香型”苹果;(4)3个早熟苹果品种间香气成分种类和含量均存在差异,苹果香气成分是早熟苹果品种选育标准评价的重要指标之一。 相似文献
996.
997.
998.
经小区试验和大面积示范推广结果表明,D型肉毒毒素水剂作为一种新型生物灭鼠制剂,不仅对高原鼠兔有较好的防治效果,而且不伤害鼠类天敌,对人、畜安全,同时减少了化学药品对草地的污染,因此,在草地鼠害治理中,推广应用这一新型生物灭鼠技术,对持续控制草地鼠害,保护草地生态环境,维护草地生物多样性有重要的现实意义。 相似文献
999.
1000.
对青海省高寒地区德令哈的主要农作物籽实大麦、青稞、小麦、豌豆、大豆、玉米、豆渣、苜蓿、油菜、小麦、豌豆等秸秆草粉的营养成分进行了测定与分析.为科学饲养牲畜、发展青海省海西州畜牧业、开辟当地饲料资源提供了依据. 相似文献