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AIM:This study was conducted to evaluate the effects of postoperative immune-enhancing parenteral nutrition on the nutritional statue,immune function,and inflammatory responses in patients undergoing portal hypertension surgery. METHODS: This study was designed as a prospective,randomized and controlled clinical trial. Forty-two patients undergoing portal hypertension surgery were randomly assigned to receive either an immune-enhancing parenteral nutrition(adding glutamine and recombinant human growth hormone,n=22) or an isocaloric and isonitrogenous control standard parenteral nutrition(n=20) for seven days. Parenteral nutrition was initiated 3 days after surgery. Blood samples were obtained on day 0,3,and 10. Host nutritional statue was evaluated by measuring levels of prealbumin and transferrin,immunity was observed by measuring levels of CD4+ cells,CD8+ cells,CD4+/CD8+,IgG,IgM and IgA,and the inflammatory responses was determined by assessing IL-2,TNF-α and C-reactive protein(CRP) levels. RESULTS:On postoperative day 10,among patients receiving an immune-enhancing parenteral nutrition,prealbumin,transferrin,CD4+ cells,CD4+/CD8+,IgG and IL-2 levels were significantly higher than those in control group,and TNF-α and CRP concentrations were significantly decreased(P<0.05). CONCLUSION:Postoperative administration of immune-enhancing parenteral nutrition in patients undergoing portal hypertension surgery can improve postoperative nutritional statue and immune function,and relieve inflammatory response. 相似文献
894.
以白灵菇菌株TN01为试材,选取香菇、杏鲍菇、白玉菇3种食用菌菇根为原料配制外援营养液,测定各营养液主要成分含量,并研究了不同类型与浓度营养液对白灵菇菌丝及子实体生长的影响,以期为白灵菇的高产栽培技术提供参考依据。结果表明:与常规PDA培养基相比,适量加入白玉菇菇根提取液可提高白灵菇菌丝生长速度;添加外援营养液对子实体的农艺性状影响不大,对产量有一定的促进作用,其中施用香菇菇根提取液的白灵菇子实体产量最高,小区总产量与对照相比提高了54.6%。施用香菇菇根提取液后对白灵菇子实体中的硝酸盐含量及蛋白质含量有提升的效果,但对亚硝酸盐及粗纤维含量无促增长的效果。 相似文献
895.
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897.
测定珍稀濒危植物贵州苏铁植株,构建不同组织和器官矿质营养元素的含量,分析矿质营养在体内分布特征及其相关特性,以及结合生长环境土壤特性分析贵州苏铁生长发育对营养需求以及土壤环境供给之间的关系,研究珍稀濒危植物贵州苏铁植株矿质营养含量及与土壤环境的相互作用,为贵州苏铁栽培和物种保护提供参考.结果表明:植株体内N、P元素含量变化较大,4a生植株体内比1 a生积累更多Fe、Mn、Zn、Ga、Mg元素,小孢子叶Zn含量最高,大孢子叶Mn含量最高,雄性叶元素含量高于雌性叶.表明贵州苏铁生长发育过程中生殖生长需要大量种类和数量的矿质营养物质,同时也证明了营养生长物质服务于生殖生长.在栽培生产中除了选择栽培基质与原生地大致相同满足植株的营养生长外,还更应注重在生殖时期对矿质营养的补给,满足植物生殖生长对矿质营养的需求. 相似文献
898.
Two field experiments (Experiment I in 2003–2005 and Experiment II in 2004–2005) with carrot c.v. ‘Kazan F1’ were conducted at Trzciana village (50°06′N, 21°85′E). The experiments were arranged in a split-plot design with four replications. Two sub-blocks were identified in both experiments: I, without foliar nutrition; II, receiving plant foliar nutrition. The plants were sprayed three times alternately with: 2% urea solution, 1% solution of multi-component ‘Supervit R’ fertilizer (produced by Intermag, Poland) and again with 2% urea solution. Combinations with diversified nitrogen fertilization were distinguished within both sub-blocks. Experiment I comprised of: (1) Control, (2) Ca(NO3)2 70, (3) Ca(NO3)2 70 + 70, (4) (NH4)2SO4 70 and (5) (NH4)2SO4 70 + 70. Experiment II included: (1) Control, (2) ENTEC-26 35 + 35, (3) ENTEC-26 70 + 70, (4) ENTEC 26 105 + 105, (5) NH4NO3 35 + 35, (6) NH4NO3 70 + 70, (7) NH4NO3 105 + 105. Where 70 kg N ha−1 was used before sowing, whereas 35 + 35, 70 + 70 and 105 + 105 kg N ha−1 were applied before sowing and as top dressing. Solid nitrogen fertilizer was added to the soil (produced by): Ca(NO3)2, Yara International ASA (Hydro); (NH4)2SO4, Zak?ady Azotowe in Tarnów, Poland; NH4NO3, Zak?ady Azotowe in Pu?awy, Poland; and ENTEC-26, COMPO GmbH & Co. KG, Germany. The research aimed at determining the effect of diversified nitrogen fertilization and foliar nutrition on NO3−, NH4+, N-total and dry matter (d.m.) concentrations in carrot, and N uptake by storage roots. In Experiment I, nitrogen fertilization did not affect NO3− concentration, whereas in Experiment II, the applied N treatment increased NO3− concentration in carrot in relation to the control, except for the storage roots of plants fertilized with ENTEC-26 35 + 35. Nitrogen fertilization applied in both experiments caused a significant increase in N-total concentration in carrot and N uptake by storage roots in comparison with the control plants. In both experiments, nitrogen fertilization had a different effect on the concentrations of NH4+ and d.m. in carrot. What is more, foliar nutrition treatments in both experiments had a different effect on the concentrations on NO3−, N-total, d.m. in carrot and N uptake by carrot storage roots. 相似文献
899.
苹果根系构型及其调控研究进展 总被引:1,自引:0,他引:1
根系是果树栽培管理的基础和中心。重点介绍了苹果根系研究试材的选择、苹果根系构型的类型以及环境营养、土壤条件、栽培容器和生长调节剂等对苹果根系形态构型的影响和调控等方面的研究进展,并提出了进一步研究的内容。 相似文献
900.
纽荷尔脐橙叶片矿质元素含量适宜值的研究 总被引:1,自引:0,他引:1
在闽西北中亚热带红壤地区,采集纽荷尔脐橙[Citrus sinensis(L.)Osbeck‘Newhall’],50个果园(范围N25°3′27″ ~ N27°8′、海拔160 ~ 660 m),100个单株的叶片、土壤和果实样品,研究果实品质及株产等级与26个矿质元素的关系。结果表明:①果实品质受叶片矿质元素的影响依次为:可溶性固形物(36.5%,贡献率,下同)> 粗纤维(27.1%)> 可滴定酸(20.0%)> 单果质量(16.1%);叶片矿质元素对品质影响的贡献率依次为:K(15.8%)> Cu(11.3%)> Ca(11.2 %)> N(10.5%)> Ni、B(8.7%)> Cd(7.8%)> P(7.4%)> Mg(7.3%),累计贡献88.7%。②叶片矿质元素对株产等级影响的标准回归系数排序为:La(–0.553)> Ni(–0.405)> Zn(+ 0.395)> Cu(–0.377)。③推荐16项叶片矿质元素诊断标准“元素(< 缺乏;适宜下限 ~ 适宜上限;> 过量)”:N(2.7% ~ 3.2%)、P(0.13% ~ 0.20%)、K(1.2% ~ 1.9%;> 2.2%)、Ca(2.5% ~ 4.0%)、Mg(< 0.20%;0.22% ~ 0.45%)、Cu(5.0 ~ 25 mg · kg-1;> 60 mg · kg-1)、Zn(20 ~ 50 mg · kg-1)、Fe(50 ~ 200 mg · kg-1)、Mn(20 ~ 150 mg · kg-1)、B(< 20 mg · kg-1;35 ~ 150 mg · kg-1)、Mo(0.05 ~ 1.0 mg · kg-1)、S(0.28% ~ 0.40%)、Cl(< 0.2%;> 0.5%);限量元素Ni(≤ 3.0 mg · kg-1)、Cd(≤ 0.3 mg · kg-1)、La(≤ 12 mg · kg-1)。 相似文献