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Steven W. Effler Carol M. Brooks Jeffrey M. Addess Susan M. Doerr Michelle L. Storey Bruce A. Wagner 《Water, air, and soil pollution》1991,55(3-4):427-444
Concentrations of Cl, total ammonia (TNH3), NO3 plus NO2, total P (TP), and soluble reactive P (SRP) were measured at two sites, located 5 km apart, on Ninemile Creek, New York, for a period of more than 8 mo. The sites bound the most recently formed Solvay waste beds, associated with the production of soda ash, that adjoin the creek. Concentrations of Cl and T-NH3 increased on average by factors of 16.1 and 7.6, respectively, over the monitored stream reach. The estimated average loadings of these materials to the stream over this reach were 2.3 × 105 and 1.2 × 102 kg d?1, respectively. These inputs are attributable to the Solvay waste beds. The loading of Cl from this source has not changed significantly over a 4 yr period since the closure of the soda ash manufacturing facility. This is the single largest source of Cl, and the second largest source of T-NH3, to polluted Onondaga Lake. Profiles of Cl in the lake indicated that at times the creek inflow plunges to subsurface layers as a result of its elevated density. This is at least in part a result of the creek's ionic enrichment. The concentration of SRP decreased by a factor of 2.0 on average over the study reach, probably due to adsorption to the CaCO3 deposits that cover the stream bed in this area. However, the TP load from the creek to the lake is not significantly affected by this phenomenon. 相似文献
43.
Olivera L Canul RR Pereira-Pacheco F Cockburn J Soldani F McKenzie NH Duncan M Olvera-Novoa MA Grant G 《Journal of agricultural and food chemistry》2003,51(1):319-325
The nutritional and physiological effects of raw cowpea (Vigna unguiculata (L) Walp.) seed meal, protein isolate (globulins), or starch on the metabolism of young growing rats have been evaluated in 14-day trials. Wet and dry weight gain, feed conversion efficiency, and lipid and protein accretion were significantly reduced as a result of inclusion of seed meal, globulins, or starch in the diet, with growth retardation being most marked with the seed meal. The proportional weights of the small intestine and pancreas were increased by meal diets, and serum cholesterol levels were slightly reduced. The globulins and raw starch also increased relative small intestine weights but had no effect on the pancreas or serum constituents. The effects of cowpeas on rats appeared to be due primarily to the combined actions of globulins, resistant starches, protease inhibitors, and possibly fiber and non-starch polysaccharides on intestinal and systemic metabolism. 相似文献
44.
黑胫病菌诱导的烟草SSH文库构建及其分析 总被引:1,自引:0,他引:1
黑胫病是危害严重的世界性烟草主要病害之一,探究烟草对黑胫病的抗病机制,可以为该病的综合防治提供理论依据。本研究以烟草黑胫病抗性品种革新3号为材料,利用黑胫病0号生理小种诱导其水平抗性,分别在接种后0.5、1、3、6、10和16 d取样,通过抑制差减杂交技术(SSH)构建cDNA文库,获得了960个阳性克隆。利用反向Northern斑点杂交技术对其中240个阳性克隆进行杂交筛选,筛选出57个表达差异明显的基因,序列拼接后获得33条高质量EST,测序及其比对分析表明,革新3号对烟草黑胫病抗性相关基因主要涉及抗病防卫、光合作用、信号传导和能量代谢等方面。进一步基因功能分析显示,病程相关PR1b蛋白、半胱氨酸蛋白、延伸因子1-α、α-微管蛋白、细胞色素P450、精胺合成酶、水通道蛋白、过氧化物酶体膜蛋白、甘氨酸延伸因子等可能参与了烟草与黑胫病菌非亲和互作过程。 相似文献
45.
中国五大湖三角帆蚌群体遗传多样性的RAPD分析 总被引:18,自引:1,他引:18
用OPJ和OPM两组40条10碱基随机引物,对中国五大湖三角帆蚌地理群体及诸暨养殖蚌进行了随机扩增多态性DNA(RAPD)分析,其中12个引物的扩增结果具有丰富的群体多态性,多态率为55.6%~80%。群体内遗传相似度大小依次为:鄱阳湖(0.8889),太湖(0.8694),洞庭湖(0.8111),诸暨(0.7746),洪泽湖(0.7348),巢湖(0.7185)。依据群体间遗传距离指数及分子系统树,表明洞庭湖群体和洪泽湖群体亲缘关系最近,鄱阳湖群体则与巢湖群体的亲缘关系最近,并且诸暨人工养殖群体与鄱阳湖和巢湖的群体比较接近。 相似文献
46.
为了提高牛体细胞克隆的效率,比较了不同融合电压对核移植胚发育的影响,其中1.7kv/cm电场强度,获得了较高的融合率、卵裂率和囊胚率,分别为67.14%,76.59%和29.16%。比较了血清饥饿处理体细胞对核移植效率的影响,血清饥饿处理体细胞后,融合率、卵裂率和囊胚率分别为68.91%,74.79%和28.26%,与非血清饥饿处理的相比没有明显差异(分别为60.96%,71.91%和20.31%,P>0.05)。而且胚胎移植后的怀孕率和产犊率也没有差异(分别为29.17%,8.33%和33.33%,16.66%,P>0.05)。另外,通过加强克隆牛的产后护理,可以提高克隆牛的成活率。总之,优化生产克隆牛的各环节因素,可以从整体上提高克隆牛的生产效率。 相似文献
47.
106头美洲水貂的后裔,根据性别分别测定其2.5、4,5、6.5月龄和屠宰取皮时的体长、胸围、体重及屠宰后肠道和楦皮的长度.结果表明育成貂的生长存在性别间的显著差异,公貂快于母貂(p<0.01).生长的最强时间在2.5~4.5月龄.随着水貂日龄的增长,体躯指数逐渐增加,体长与植皮长的相关程度也越来越高.体长、胸围与体重之间的相关系数分别为:公貂 0.7529和 0.6358,母貂 0.6606和0.5203。 相似文献
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50.
Hohng S Zhou R Nahas MK Yu J Schulten K Lilley DM Ha T 《Science (New York, N.Y.)》2007,318(5848):279-283
Despite the recent advances in single-molecule manipulation techniques, purely mechanical approaches cannot detect subtle conformational changes in the biologically important regime of weak forces. We developed a hybrid scheme combining force and fluorescence that allowed us to examine the effect of subpiconewton forces on the nanometer scale motion of the Holliday junction (HJ) at 100-hertz bandwidth. The HJ is an exquisitely sensitive force sensor whose force response is amplified with an increase in its arm lengths, demonstrating a lever-arm effect at the nanometer-length scale. Mechanical interrogation of the HJ in three different directions helped elucidate the structures of the transient species populated during its conformational changes. This method of mapping two-dimensional reaction landscapes at low forces is readily applicable to other nucleic acid systems and their interactions with proteins and enzymes. 相似文献