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61.
62.
目的:探讨1,6二磷酸果糖(FDP)治疗中、重度新生儿缺氧缺血性脑病(HIE)的价值。方法:将71例中、重度新生儿HIE随机分为2组,FDP与胞二磷胆碱(CDPC)联合应用41例作为观察组,单独应用CDPC 30例为对照组,通过对临床异常神经症状、体征消失时间及20项新生儿神经行为评分作为疗效及预后评价指标。结果:在治疗有效率、显效率及生后d7、d14的20项NBNA评分上,观察组与对照组比较差异有显著性(P<0.05,P<0.01)。结论:早期加用FDP治疗HIE较传统单一用药临床疗效更满意。  相似文献   
63.
Soils are the third biggest sink of carbon on the earth. Hence, suitable land uses for a climatic condition are expected to sequester optimum atmospheric carbon in soils. But, information on how climatic conditions and land uses influence carbon accumulation in the soils on the Himalayan Mountains is not known. This study reports the impact of four climatic conditions (sub-tropical, altitude: 500–1200 m; temperate 1200–2000 m; lower alpine 2000–3000 m; upper alpine, 3000–3500 m) and four land uses (forest, grassland, horticulture, agriculture) on the concentrations and stocks of soil organic carbon (SOC) in upper (0–30 cm) and deeper (30–100 cm) soil depths on the western Himalayan Mountains of India. The study also explored the drivers which influenced the SOC stock build up on the mountains. Rainfall and soil moisture showed quadratic relations, whereas temperature declined linearly with the altitude. SOC stock as well as concentration was the highest (101.8 Mg ha− 1 in 0–30 cm, 227.97 Mg ha− 1 in 0–100 cm) in temperate and the lowest in sub-tropical climate (37 Mg ha− 1 in 0–30 cm, 107.04 Mg ha− 1 in 0–100 cm). Pattern of SOC stock build up across the altitude was: temperate > lower alpine > upper alpine > sub-tropical. SOC stocks in all land uses across the climatic conditions, except agriculture in lower alpine, was higher (0.7 to 41.6%) in the deeper than upper soil depth. SOC stocks in both the depths showed quadratic relations with soil temperature and soil moisture. Other factors like fine soil particles, land-use factor and altitude influenced positively whereas slope and pH, negatively to the SOC stocks. In all climatic conditions, other than temperate, SOC stocks were greater in natural ecosystems like forests and pastures (112.5 to 247.5 Mg ha− 1) than agriculture (63 to 120.4 Mg ha− 1). In temperate climate, SOC stock in agriculture (253.6 Mg ha− 1) on well formed terraces was a little higher than forest (231.3 Mg ha− 1) on natural slope. These observations, suggest that land uses on temperate climate may be treated as potential sinks for sequestration of the atmospheric carbon. However, agriculture in subtropical climate need to be pursued with due SOC protection measures like the temperate climate for greater sequestration of the atmospheric carbon.  相似文献   
64.
玉米无公害生产是一个复杂的系统管理过程,这个过程要充分考虑各种环境因子,以粮饲兼用玉米为中心,充分利用各种手段和方法为玉米创造最佳的生长环境,对病虫草害进行综合治理,对玉米生产进行产前、产中、产后全方位控制,从而达到无公害生产目的.  相似文献   
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66.
薛利红  周鼎浩  李颖  杨林章 《土壤学报》2014,51(5):993-1002
以太湖流域直湖港小流域稻田、桃园和菜地的土壤样本为研究对象,研究了不同光谱建模方法和土地利用方式对土壤有机质和全磷高光谱反演的影响。结果表明:(1)偏最小二乘回归分析(Partial least squarer egression,PLSR)模型的建模和预测精度较高且稳定;人工神经网络中广义回归神经网络(Generalized regression neural network,GRNN)网络预测精度较高但易出现过拟合现象,反向传播神经网络(Back propagation neural network,BPNN)网络比较稳健但精度略低;偏最小二乘与人工神经网络相结合则可综合两者优点,改善复杂样本下的预测精度。(2)土壤有机质的光谱反演结果优于全磷。3种土地利用方式中,稻田的预测效果总体优于桃园和菜地。在当前研究区域内土地利用方式对土壤有机质光谱反演影响不大,但对全磷反演影响较大。今后利用光谱对土壤全磷反演时需分土地利用方式对模型进行校准。  相似文献   
67.
Flour samples were prepared from fermented and unfermentedAfrican oil bean (Pentaclethra macrophylla) seeds (AOBS). The flour samples were evaluated for proximate composition and certain functional properties. The influenceof defatting on these properties was also determined. Fermentation significantly increased (p<0.05) the proteinand decreased the crude fiber, ash, fat and carbohydrate contents of the AOBS flours. The nitrogen solubility of both fermented and unfermented flours was pH dependent withminimum and maximum solubility at pH 4.0 and pH 8.0, respectively, and with increased nitrogen solubility in the fermented sample. The fermented and unfermented flour sampleshad least gelation concentrations of 14 and 16% (w/v), respectively. The water absorption capacity and foam capacitiesof the fermented flour were 36 and 34%, respectively, over the unfermented seed flour. On the other hand, fermentation decreased the fat absorption capacity, emulsion activity and emulsion and foam stabilities. Fermentation decreased (p<0.05) the bulk density of AOBS flour by 15%. Defattingimproved all the functional properties evaluated except emulsion activity. These results indicate potential food usesof fermented and unfermented AOBS flour samples as protein supplements in diets and as functional ingredients in formulated foods.  相似文献   
68.
沱江流域不同土地利用方式紫色土有机碳储量特征   总被引:3,自引:0,他引:3  
沱江流域是长江上游四川境内的重要支流,紫色土为其主要的耕地资源。由于长期人口过载和不合理利用,流域内紫色土退化普遍严重。以四川盆地沱江流域紫色土为研究对象,按流域各区段分上中下游三层选样,研究不同土地利用方式下紫色土有机碳储量特征,为紫色土退化评估及地力维护提供参考。结果显示,不同土地利用方式紫色土壤有机碳总量以林地(13.876g/kg)显著高于果园地(9.655g/kg)、菜园地(9.261g/kg)、草坡地(7.968g/kg),以玉米地(6.134g/kg)最低。水溶性有机碳的含量呈现林地〉果园地〉菜园地〉草坡地〉玉米地趋势。同时,流域上、中、下游紫色土有机碳总量总体上差异显著,且以上游区段紫色土壤有机碳总量最高。流域中下游紫色土有机碳总量变化较大。其中,林地以下游高于中游,果园及草坡地以中游高于下游。而且,菜园地、玉米地在3个区段上差异未达显著水平。沱江流域紫色土有机碳储量总体特征表现上游最高,中下游变化复杂,下游略高于中游区域。  相似文献   
69.
Rice varieties such as IR-20, Ponni, Bhavani and IR-50 that are preferred for cooking showed larger surface area, higher water uptake at 96°C, greater cooked volume, soft gel consistency and greater elongation ratio. Rice varieties which are exclusively used for makingidli anddosai exhibited lower protein content, medium alkali score and higher percentage of total as well as soluble starch and amylopectin. Rice varieties which are used for making flakes showed hard gel consistency, higher alkali digestibility values, lower soluble amylose content and relatively higher amount of hot water-soluble reducing sugars. Varieties used for making puffed rice do not show any specific characteristics to differentiate them from the above types. All the rice varieties studied belong to the high amylose group except ASD-1 which belongs to the medium amylose group.  相似文献   
70.
Endoplasmic reticulum (ER) is a multifunctional organelle responsible for the synthesis and folding of proteins and regulation of calcium homeostasis. Multiple stimuli, such as oxidative stress, glycosylation change and so on, lead to ER dysfunction characterized by the accumulation of unfolded and/or misfolded proteins and calcium homeostasis imbalance (ER stress). Mode-rate ER stress is an important cytoprotective mechanism against stressors. However, severe and/or prolonged ER stress can trigger apoptotic signaling including CHOP, caspase-12 and JNK pathways. Recent studies have shown that ER stress plays a critical role in the development of atherosclerosis and it can bring about inhibitory effects on the progression of atherosclerosis through the intervention of the relevant pathways, which may be a new therapeutic target for atherosclerosis.  相似文献   
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