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941.
Alkaline phosphatase (ALP) is an ecto-enzyme widely distributed across species. It modulates a series of transmembranar transport systems, has an important role in bone mineralization, and can also be involved in vascular calcification. Polyphenol-rich diets seem to have protective effects on human health, namely, in the prevention of cardiovascular diseases. We aimed to investigate the effects of polyphenols and polyphenol-rich beverages upon membranar alkaline phosphatase (ecto-ALP) activity in intact human vascular smooth muscle cells (AALTR). The ecto-ALP activity was determined at pH 7.8, with p-nitrophenyl phosphate as the substrate, by absorbance spectrophotometry at 410 nm. Cell viability was assessed by the lactate dehydrogenase (LDH) method, and the polyphenol content of beverages was assessed using the Folin-Ciocalteu reagent. All polyphenols tested inhibited ecto-ALP activity, in a concentration-dependent way. Teas, wines, and beers also inhibited ecto-ALP activity, largely according to their polyphenol content. All tested compounds and beverages improved or did not change AALTR cell viability. Stout beer was an exception to the described behavior. Although more studies must be done, the inhibition of AALTR ecto-ALP activity by polyphenolic compounds and polyphenol-containing beverages may contribute to their cardiovascular protective effects.  相似文献   
942.
The fatty acid composition of 67 commercial presentations of table olives was determined. The most abundant fatty acids, in decreasing order of presence, were C18:1, C16:0, C18:2 n-6, and C18:0. The ranges, expressed as grams of fatty acids per 100 g of edible portion, for the different nutritional fractions were as follows: saturated fatty acids, 2.07-5.99; monounsaturated fatty acids, 5.67-19.42; polyunsaturated fatty acids, 0.52-3.87; and trans-fatty acids, 0.08-0.44. Principal component analysis of the matrix of the fatty acid composition led to the deduction of new factors. The first accounted for 55.10% of the total variance and was mainly related to C16:10, C18:0, C20:0, C22:0, C24:0, C18:1, C18:1t, and C20:1. The second factor accounted for 10.33% of variance and was related to C16:1 and C18:2 n-6. They did not permit differentiation among elaboration types or cultivars. However, discriminant analysis was successfully applied for this objective. The fatty acids that most contributed to discriminate among elaboration styles were C17:1, C18:1, C16:0, C17:0, and C18:0 (function 1) and C17:0, C17:1, C20:0, C16:0, C18:1, and C24:0 (function 2). In the case of cultivars, they were C20:0, C18:1, C17:1, C18:2 n-6, C18:1t, and C18:2t (function 1); C18:2 n-6, C18:1, C16:0, C20:0, C18:0, and C18:2t (function 2); and C17:0, C18:3 n-3, and C17:1 (function 3). Results from this study have shown differences among the fatty acid composition and fat content of the diverse commercial presentations of table olives, which can be applied in predictive and classification discriminant analysis.  相似文献   
943.
Background:Genetic selection in cattle has been directed to increase milk production.This,coupled to the fact that the vast majority of bovine artificial inseminations(AI)are performed using cryopreserved sperm,have led to a reduction of fertility rates over the years.Thus,seeking sensitive and specific sperm biomarkers able to predict fertility rates is of vital importance to improve cattle reproductive efficiency.In humans,sperm chromatin condensation evaluated through chromomycin A3(CMA3)has recently been purported to be a powerful biomarker for sperm functional status and male infertility.The objectives of the present study were:a)to set up a flow cytometry method for simultaneously evaluating chromatin condensation and sperm viability,and b)to test whether this parameter could be used as a predictor of in vivo fertility in bulls.The study included pools of three independent cryopreserved ejaculates per bull from 25 Holstein males.Reproductive outcomes of each sire were determined by non-return rates,which were used to classify bulls into two groups(highly fertile and subfertile).Results:Chromatin condensation status of bovine sperm was evaluated through the combination of CMA3 and Yo-Pro-1 staining and flow cytometry.Sperm quality parameters(morphology,viability,total and progressive motility)were also assessed.Pearson correlation coefficients and ROC curves were calculated to assess their capacity to predict in vivo fertility.Sperm morphology,viability and total motility presented an area under the ROC curve(AUC)of 0.54,0.64 and 0.68,respectively(P>0.05),and thus were not able to discriminate between fertile and subfertile individuals.Alternatively,while the percentage of progressively motile sperm showed a significant predictive value,with an AUC of 0.73(P=0.05),CMA3/Yo-Pro-1 staining even depicted superior results for the prediction of in vivo fertility in bulls.Specifically,the percentage of viable sperm with poor chromatin condensation showed better accuracy and precision to predict in vivo fertility,with an AUC of 0.78(P=0.02).Conclusions:Chromatin condensation evaluated through CMA3/Yo-Pro-1 and flow cytometry is defined here as a more powerful tool than conventional sperm parameters to predict bull in vivo fertility,with a potential ability to maximising the efficiency of dairy breeding industry.  相似文献   
944.
Investment in silvicultural techniques is notice-ably lacking,especially in breeding programs for non-con-ventional wood species.Studying genotype × environment interaction (G × E) is essential to the development of breed-ing programs.Thus,this study aimed to estimate genetic diversity of and the effects of G × E interaction on two prog-eny tests of Cordia trichotoma,including the estimation of genetic gain and genetic diversity after selection.For the experiment,30 progenies of C.trichotoma were tested at two sites with differing soil textures.Diameter at breast height (1.30 m above soil surface,dbh-cm),total height,diameter at 30 cm from the soil,first branch height,and survival were all monitored for four years.Statistical devi-ance,best linear unbiased estimator,and harmonic mean of relative performance of genetic values (MHPRVG) were all calculated to predict breeding values,estimate genetic parameters,and analyze deviance.All quantified traits varied significantly among progenies by soil type,with greatest variation recorded for genetic variability.Heritability of the progenies led to predictions of genetic gain,ranging from 7.73 to 15.45%,for dbh at four years of age.The calculated decrease in genetic diversity after selection showed that this parameter should be monitored in subsequent breed-ing cycles.G × E was low for all tests.The best-performing progenies proved most stable and best adapted to the differ-ent environmental conditions tested.  相似文献   
945.

Aims

This study aims to evaluate the effects of wood ash application on nutrient dynamics and soil properties of an acidic forest soil (Arenosol).

Methods

Treatments were loose and pelleted ash application (11?Mg?ha?1), alone or together with N fertiliser, and control treatment in a lysimeter experiment. Nutrient leaching was followed during a 2-year period and soil chemical and biological properties were evaluated at the end of the experiment.

Results

Wood ash increased leaching of total N, NH 4 + -N, base cations and P, mainly during the first months, the effect being more pronounced for the loose formulation. At the end of the study period, a positive effect on soil nutrient availability and soil acidity reduction was seen. The application of loose and pelleted ash alone decreased N leaching and increased N microbial biomass at the end of the experiment. The C dynamics was weakly affected.

Conclusion

Wood ash can be used to improve nutrient availability and balance nutrient exported by tree harvesting in acid forest soils, the effects at short-term being stronger for loose than for pelleted ash. However, their application should be carried out when vegetation is established to minimise nutrient losses at short-term and reduce the potential risk for water bodies. In N-limited soils, wood ash should be applied with N fertilisers to counteract N immobilisation.  相似文献   
946.
Araucaria forest, named due to the high abundance of Araucaria angustifolia, occurs mainly in the southern Brazilian highlands, and the abundance of A. angustifolia in the forest is a current forest issue. The present study aimed at evaluating a potential allelopathic effect of A. angustifolia needle extracts that could mediate plant successional dynamics in the Araucaria forests. Senescent araucaria needles from A. angustifolia were evaluated for their allelopathic potential on Lactuca sativa through an in vitro study. The effect was evaluated by determining the germination of seeds, length of seedling and germination rate. The allelopathic potential of the A. angustifolia was confirmed for the highest doses tested (187.5 and 250?mg of the extracts). The potential allelochemical compounds identified were ent-kaurene and phyllocladene. In conclusion, A. angustifolia showed a potential allelophatic effect that may play an important role in successional dynamics of Araucaria forests.  相似文献   
947.
本研究通过抗性接种鉴定对从普通小麦品种烟农15与八倍体小滨麦杂交后代中选育的抗白粉病小滨麦易位系山农6343的白粉病抗性遗传特点进行了分析,结果表明,山农6343的白粉病抗性由显性单基因控制,暂将其命名为PmSn6343(t);利用辉县红与山农6343杂交构建了包含302个家系的F2分离群体,对其进行白粉病抗性基因分子标记的连锁分析和染色体定位。在分析的1980对SSR、EST-SSR和STS引物中,有403对基因组SSR引物可在亲本间揭示多态性差异,其中Wmc658和Barc122两个引物在优选小群体中可以扩增出多态性谱带;采用F2群体对两个标记进行连锁分析证明Wmc658和Barc122与山农6343抗白粉病基因PmSn6343(t)的连锁距离分别为3.4cM和5.4cM,并将抗白粉病基因定位在染色体2AL上。利用F2:3家系对两个标记进行验证,结果表明,两个标记是与白粉病抗性基因PmSn6343(t)连锁的可靠分子标记。  相似文献   
948.
本文以京411/红忙春21构建的重组自交系群体(RILs)为研究材料,通过对小麦抽穗期、盛花期和灌浆期旗叶叶绿素含量分布频率的分析,得出叶绿素含量在花后7d以前多呈正态分布,而灌浆中后期呈偏态分布或双峰分布,说明前者为受多基因控制的数量性状,而后者存在与其相关的主效基因。在多个生长发育时期中,旗叶叶绿素含量呈现先上升后下降的趋势,在盛花期达到最大值,花后24d,叶绿素含量则急剧下降,成熟时接近为0。在RILs群体中对小麦细胞分裂素氧化酶基因等位变异进行鉴定,得出TaCKOX4基因在群体中表现较好的多态性,其变异与小麦旗叶多个生长发育时期(如抽穗期,盛花期及灌浆期)叶绿素含量呈显著或极显著相关,且具有A带型家系的叶绿素含量显著高于B带型家系的叶绿素含量,说明TaCKOX4基因变异与小麦旗叶叶绿素含量关系密切。  相似文献   
949.
转双价抗虫基因BmkIT-Chitinase玉米株系的获得   总被引:2,自引:0,他引:2  
通过超声波辅助花粉介导法,将双价抗虫基因BmkIT-Chitinase分别导入以玉米自交系昌7-2及郑58的花粉为受体的不同基因型的自交系中。本研究共处理玉米雌穗1072穗,获得T0代种子1563粒,经卡那霉素初筛,T1代~T4代PCR及SouthernBlot杂交分子跟踪检测共获得20个转化株系,田间抗虫性鉴定表明共有16个转化株系与对照在抗虫性方面有显著差异,且此抗性随着各代稳定遗传。农艺性状调查结果表明,所获得的转基因玉米株系中大部分材料的农艺性状与对照无显著差异,除了N55材料及N20-1材料。N55材料的穗位高度与对照相比略低6±0.5cm,而穗粒数增加75±5粒。而N20-1材料百粒重增加5±0.5g。因此,转入此双价抗虫基因对玉米农艺性状影响不是很大。经过分子检测、田间抗虫性鉴定及农艺性状调查我们最终选育了9个转双价抗虫基因昌7-2自交系优良株系,6个郑58转双价抗虫基因自交系优良株系。  相似文献   
950.
以辣椒属5个栽培种叶片为试材,利用Ty1-copia类逆转座子逆转录酶的保守序列设计简并引物,PCR扩增后均获得了260bp左右的目的条带。对C.annuum的扩增产物进行纯化、克隆和测序,经Mega4和DNAstar软件分析后,获得25条逆转录酶序列,核苷酸序列长度变化范围为225~272bp,这些序列存在高度的异质性,主要表现为缺失突变,同源性范围为23.1%~93.2%,核苷酸聚类分为7个组。翻译成氨基酸后,有9条序列存在1~3个不同程度的终止密码子突变,4条序列存在移框突变。将这25条逆转录酶的氨基酸序列与已发表的不同物种同一类型逆转座子的逆转酶序列进行聚类分析,表明辣椒的Ty1-copia型逆转座子与烟草、矮牵牛、马铃薯有很近的关系。  相似文献   
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