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目的:观察苦参注射液对慢性乙型肝炎性肝硬化的临床效果及其作用机制.方法将58例慢性乙型肝炎性肝硬化患者随机分为观察组和对照组,在一般支持治疗的基础上,观察组加用苦参注射液,治疗8周后,比较两组肝功能、肝纤维化指标.结果观察组肝功能改善显著,肝纤维化减轻,与对照组比较差异均有统计学意义(P〈0.05).结论在正常治疗基础上加用苦参注射液,有助于肝炎性肝硬化患者的肝功能恢复,有较好的临床效果.其作用机制可能是通过影响外周单核细胞IL-10表达、调节机体促炎抗炎平衡而实现的. 相似文献
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【目的】探究牡丹品种分类的等级和标准,进而为其品种选育和资源研究提供参考。【方法】2013-03-05,观测了39个牡丹品种的26个质量和数量性状,首先对26个性状指标进行了R型聚类分析和主成分分析,然后根据R型聚类结果,去掉相关性大的指标,再对39个牡丹品种进行了Q型聚类分析。【结果】R型聚类结果显示,花瓣基部有无色斑与色斑颜色(r=0.766),复叶长与复叶宽(r=0.659)的相关性较大,因此Q型聚类中不考虑色斑颜色和复叶宽2个性状。主成分分析结果表明:结实率、花瓣基部色斑情况、花期、花冠情况等12个性状的贡献率较大。Q型聚类结果显示,39个牡丹品种依据结实率、花瓣基部有无色斑和花期被分为3类:结实率高且花期较早的类群,如“赵粉”、“肉芙蓉”、“迎日红”、“粉中冠”等;结实率低且花瓣基部没有色斑的类群,如“状元红”、“绿香球”、“大胡红”、“珊瑚台”等;结实率低且花瓣基部有色斑的类群,如“红宝石”、“卷叶红”、“十八号”、“菱花湛露”等。【结论】筛选出对牡丹品种分类贡献较大的13个性状,得到可以作为其形态学分类依据的性状有结实率、花瓣基部有无色斑和花期。 相似文献
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Fungal breakdown of plant material rich in lignin and cellulose (i.e. lignocellulose) is of central importance to terrestrial carbon (C) cycling due to the abundance of lignocellulose above and below-ground. Fungal growth on lignocellulose is particularly influential in tropical forests, as woody debris and plant litter contain between 50% and 75% lignocellulose by weight, and can account for 20% of the C stored in these ecosystems. In this study, we evaluated factors affecting fungal growth on a common wood substrate along a wet tropical elevation gradient in the Peruvian Andes. We had three objectives: 1) to determine the temperature sensitivity of fungal growth - i.e. Q10, the factor by which fungal biomass increases given a 10 °C temperature increase; 2) to assess the potential for above-ground fungal colonization and growth on lignocellulose in a wet tropical forest; and 3) to characterize the community composition of fungal wood decomposers across the elevation gradient. We found that fungal growth had a Q10 of 3.93 (95% CI of 2.76-5.61), indicating that fungal biomass accumulation on the wood substrate nearly quadrupled with a 10 °C increase in temperature. The Q10 for fungal growth on wood at our site is higher than Q10 values reported for litter decomposition in other tropical forests. Moreover, we found that above-ground fungal growth on the wood substrate ranged between 37% and 50% of that measured in the soil, suggesting above-ground breakdown of lignocellulose represents an unexplored component of the C cycle in wet tropical forests. Fungal community composition also changed significantly along the elevation gradient, and Ascomycota were the dominant wood decomposers at all elevations. Fungal richness did not change significantly with elevation, directly contrasting with diversity patterns observed for plant and animal taxa across this gradient. Significant variation in fungal community composition across the gradient suggests that the characteristics of fungal decomposer communities are, directly or indirectly, influenced by temperature. 相似文献
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Abrupt increases in the temperature sensitivity of soil respiration below 0 °C have been interpreted as a change in the dominance of other co-dependent environmental controls, such as the availability of liquid-state water. Yet the relationship between unfrozen water content and soil respiration at sub-zero temperatures has received little attention because of difficulties in measuring unfrozen water contents. Using a recently-developed semi-solid 2H NMR technique the unfrozen water content present in seasonally frozen boreal forest soils was quantified and related to biotic CO2 efflux in laboratory microcosms maintained at temperatures between −0.5 and −8 °C. In both soils the unfrozen water content had an exponential relationship with temperature and was increased by addition of KCl solutions of defined osmotic potential. Approximately 13% unfrozen water was required to release the dependence of soil respiration on unfrozen water content. Depending on the osmotic potential of soil solution, this threshold unfrozen water content was associated with temperatures down to −6 °C; yet if temperature were the predictor of CO2 efflux, then the abrupt increase in the temperature sensitivity of CO2 efflux was associated with −2 °C, except in soils amended with −1500 kPa KCl which did not show any abrupt changes in temperature sensitivity. The KCl-amendments also had the effect of decreasing Q10 values and activation energies (Ea) by factors of 100 and three, respectively, to values comparable with those for soil respiration in unfrozen soil. The disparity between the threshold temperatures and the reductions in Q10 values and activation energies after KCl amendment indicates the significance of unfrozen water availability as an environmental control of equal importance to temperature acting on sub-zero soil respiration. However, this significance was diminished when soils were supplied with abundant labile C (sucrose) and the influences of other environmental controls, allied to the solubility and diffusion of respiratory substrates and gases, are considered to increase. 相似文献
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为明确烟粉虱Bemisia tabaci取食感染番茄黄化曲叶病毒(Tomato yellow leaf curl virus,TYLCV)的番茄植株后,其体内的芳香基硫酸酯酶B基因(arylsulfatase B,ARSB)是否能够做出应答反应,基于Q型烟粉虱基因组数据克隆得到ARSB基因cDNA全长,采用生物信息学方法分析其序列特征,并通过实时荧光定量PCR技术测定ARSB基因在Q型烟粉虱不同发育阶段、不同组织及携带TYLCV前后的表达量变化情况。结果显示:Q型烟粉虱ARSB基因的cDNA全长为1 731 bp,编码576个氨基酸,分子量为64.89 kD,具有ARSB的保守结构域。ARSB基因在Q型烟粉虱不同发育阶段均有表达,在卵期表达量最高,成虫期表达量最低;该基因在Q型烟粉虱头胸部的表达量显著高于腹部;Q型烟粉虱获取TYLCV 72 h后其体内ARSB基因表达量显著提高。表明ARSB基因在Q型烟粉虱不同龄期、不同组织内存在差异表达,并可能参与Q型烟粉虱对TYLCV的响应和传毒过程。 相似文献
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分别在棉田和茶园开展了添加不同浓度的竹醋液对5%氟铃尿防治斜纹夜蛾1~2龄幼虫和10%吡虫啉防治茶小绿叶蝉的增效研究,结果表明:5%氟铃尿添加稀释400倍竹醋液防治斜纹夜蛾1~2龄幼虫,施药后7d增效作用显著,施用农药推荐剂量的一半可达到推荐剂量的防效。10%吡虫啉添加稀释400倍竹醋液防治茶园茶小绿叶蝉,施药后1d、3d和7d、11d增效作用均显著,施药后1d、3d施用农药推荐剂量的一半可达到推荐剂量的防效,但添加稀释600倍竹醋液,施药后1d增效作用显著,施药后3d、7d和11d增效作用不显著。 相似文献
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基于铜,邻二氮菲和溴酚兰形成Cu:phen:BPB为1:3:1的三元配合物且丁基罗丹明B与溴酚兰形成经BPB:BRB为1:3的等色染料离子对,建立了等色染出子对萃取法测Cu的新方法,该法摩尔吸光系数为2.86×10^5L.mol^-1.cm^-1线性9.44×10^-7-8.65×10^-5mol.L^-1。 相似文献