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31.
Polymorphonuclear leukocytes (PMNLs) were isolated from an inflammatory exudate induced in the intercarpal joints of horses by an administration of carrageenin. Their superoxide production at rest and following stimulation with either serum-treated zymosan (STZ) or phorbol myristate acetate (PMA) was measured by cytochrome-c reduction. Stimulation of the cells increased the cytochrome-c reduction 10-15 times that of resting cells. The maxima were 20 nmol of reduced cytochrome-c per 10(6) cells per ml at 120 min (STZ) and 35 nmol of reduced cytochrome-c per 10(6) cells per ml at 60 min (PMA). The maximum inhibition of the cytochrome-c reduction by superoxide dismutase (Palosein) was 83.6% (STZ stimulation) and 72.1% (PMA stimulation). The non-steroidal anti-inflammatory drugs, phenylbutazone, salicylic acid, aspirin, sodium salicylate in addition to D-penicillamine and dimethylsulfoxide caused dose-dependent inhibition of the cytochrome-c reduction when the cells were stimulated by PMA. The maximum inhibitions were 64% and 36% for aspirin (10(-2) M), 32% and 17% for phenylbutazone (10(-3) M), 15% and 31% for dimethylsulfoxide (6.4 x 10(-1) M), 32% and 19% for salicylic acid (10(-2) M), 0% and 17% for sodium salicylate (10(-2) M) and 2.2% and 2.5% for D-penicillamine (10(-4) M) when the cells were stimulated by STZ and PMA, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
32.
百合无病毒苗快速繁殖技术   总被引:3,自引:0,他引:3  
以东方百合珠芽作为外植体进行脱毒苗的组织培养快速繁殖技术的研究,结果表明诱导愈伤组织的最适培养基为MS附加BA0.5mg·L-1和NAA0.1mg·L-1,培养7d后愈伤组织就启动,愈伤组织的诱导率达到90.5%;最适宜分化的培养基为MS BA1.5mg·L-1 KT0.1mg·L-1 NAA0.1mg·L-1,培养8d即开始分化出丛状芽,分化率可达到93.33%;最适宜芽增殖培养基为MS附加BA0.5mg·L-1和NAA0.05mg·L-1,繁殖系数达到5.4;无根苗转入1/2MS IAA1.0mg·L-1,100%生根;经检测,0.3~0.8mm的外植体,均能达到脱毒的要求。  相似文献   
33.
选择经产、胎次相同和产奶量相近的荷斯坦奶牛40头,配对分组设计分为对照组和试验组,每组20头。对照组全程饲喂基础日粮,试验组饲喂基础日粮 瘤胃稳定性脂肪。结果:瘤胃稳定性脂肪对奶牛采食量无显著影响(P>0.05);试验组牛产奶量显著升高(P<0.05),乳脂率呈上升趋势(P>0.05),但乳蛋白率未见显著变化(P>0.05);试验组奶牛外周血白细胞总数和淋巴细胞数轻度上升(P>0.05),牛奶SCC呈下降趋势(P>0.05)。结果表明,补充瘤胃稳定性脂肪可提高产奶量,对于改善机体免疫机能有一定的作用。  相似文献   
34.
为延迟‘桂热杧82号’采收期,提高杧果种植效益,对‘桂热杧82号’在不同花期进行短截花枝处理试验。结果表明,在原生花序初花期、盛花期短截花枝并配套相应的栽培技术,‘桂热杧82号’均易抽出再生花序,再生花序盛花期较对照分别推迟约30~35d、40~50d,采收期较对照分别推迟约30d、40d,且产量较对照显著增加,分别是对照的1.63倍、2.25倍;有胚果数量较对照明显增多,分别是对照的1.39倍、2.25倍;采收期果实品质与对照无明显差异。原生花序初花期、盛花期短截花枝是推迟‘桂热杧82号’上市的有效措施。  相似文献   
35.
结合新疆生产建设兵团城镇化建设自身特点,将生态环境指标和社会稳定指标作为重要的考核因素,形成一种全方位的城镇化综合评价因子。以《新疆生产建设兵团统计年鉴2014》中兵团14个师的数据为例,运用PCA方法,将影响评价兵团城镇化发展水平的20个主要因子,分为社会发展、经济建设、基础建设、社会稳定和生态环境5个方面,构建了兵团城镇化发展的新型评价指标体系。  相似文献   
36.
高寒草甸草地水、土、草中氮硫含量冷暖季节的变化   总被引:3,自引:0,他引:3  
根据青海高原特殊的气候分布特征,把高寒草甸草地绵羊放牧地划分为冷季和暖季。通过测定冷暖绵羊放牧地水、土壤、牧草中氮和硫含量的结果表明:水、土壤、牧草中氮和硫的含量暖季>冷季(P<0.05),其中地表水冷季含硫量分别为3.7mg/kg、5.1mg/kg,水中没有检测到氮;牧草中硫含量冷暖季分别为2952mg/kg,3262mg/kg,差异显著(P<0.05);牧草中氮含量冷暖季分别为0.62%、1.36%,差异显著(P<0.05);土壤氮含量冷暖季分别为0.22%、0.285%,差异显著(P<0.05);硫含量冷暖季分别为0.24%、0.37%。  相似文献   
37.
In order to assess the water runoff on the sloping cultivated fields of Central Greece, an experiment was carried out from 1997 to 2000. The following treatments were used: three tillage methods, viz. conventional tillage, reduced tillage with heavy cultivator and disk-harrow; two with or without winter cover crop; two parallel and perpendicular to the contour tillage and planting directions.An existing methodology for predicting runoff was evaluated and improved, which is based on the estimation of ponding time for the different tillage systems in the study area under rainfall. An equation predicting the time to ponding was used obtaining data from infiltration experiments using double-cylinder infiltrometers in the field. The surface runoff of each rain storm was estimated by combining the appropriate infiltration equation with the rain intensity data, taking into consideration not only the excess rainfall rate over the infiltration rate, but also the surface detention.Measured runoff was used to test the validity of the USDA-Soil Conservation Service (SCS) curve number method in the region. The results from this test indicated that this prediction runoff method may not be used in the region without the proper modifications to suit the rainfall in the region.The developed model could be used to successfully estimate runoff and erosion in the area. It was found that the combination of equations of time to incipient ponding and the maximum surface storage capacity of topsoil, could explain about 85% of the existing runoff variation.  相似文献   
38.
The determination of the steroid acetates was evaluated for ruggedness of the method by using an octyldecylsilane column, 254 nm detection, and acetonitrile-water as mobile phase. Mobile phase pH, oven temperature, and columns from various manufacturers had no dramatic effect on the chromatography. The method was then optimized for dexamethasone acetate and cortisone acetate bulk drug and dosage forms. For dexamethasone acetate, the bulk drug substance should be dried at 105 degrees C before use, and the sample should be dissolved in 50% acetonitrile-buffer pH 6 for stability. Cortisone acetate, on the other hand, was found to be nonhygroscopic and hence could be used as received. For stability, the sample should be stored in 50% acetonitrile-buffer pH 4.  相似文献   
39.
成年猪结肠按常规制备石蜡切片,用甲苯胺蓝改良法显示肥大细胞.结果粘膜型肥大细胞(MMCs)主要分布于固有膜深层,不同部位结肠粘膜中MMCs的数量存在极显著差异(P>0.01),结缔组织型肥大细胞(CTMCs)主要分布于粘膜下层且不存在数量上的区域性差异(P>0.05).结论猪结肠MMCs的分布类型具有区域异质性特征.  相似文献   
40.
不同价态外源硒对冬小麦生长及生理代谢的影响   总被引:5,自引:1,他引:5       下载免费PDF全文
用盆栽试验研究了不同浓度外源硒(四价和六价)处理土壤对小麦生长和生理代谢的影响,旨在为富硒小麦的种植和开发提供理论依据。结果表明:外源硒抑制了苗期小麦的生长(株高和生物量);而在生长后期,随外源硒浓度增加表现为先促进后抑制作用。Se(Ⅳ)和Se(Ⅵ)处理对小麦生物量影响的EC10分别从苗期的1.40mg·kg-1和0.28mg·kg-1增加到收获期的28.48mg·kg-1和4.56mg·kg-1,表明小麦对硒的耐受浓度随生长时间的延长逐渐增大。Se(Ⅵ)低浓度(≤1mg·kg-1)对小麦生长的促进作用及高浓度(≥2.5mg·kg-1)对小麦生长的抑制作用均大于Se(Ⅳ)。小麦籽粒产量随外源Se(Ⅳ)和Se(Ⅵ)浓度的增大先升高而后降低,分别在2.5mg·kg-1和1mg·kg-1浓度处理时达到最大。低浓度硒处理(Se(Ⅳ)≤5mg·kg-1和Se(Ⅵ)≤0.5mg·kg-1)能促进拔节期小麦叶片中GSH和POD等抗氧化酶活性,显著降低叶片过氧化物质MDA(Se≤2.5mg·kg-1)含量,高浓度硒处理则与之相反。  相似文献   
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