94 resultados para B-2-10-SF


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人类向大气中排放的大量氮氧化合物和氟氯烃类化合物(CFC’s)引起臭氧分子的分解,导致到达地球表面的紫外辐射增加,特别是UV-B辐射增强。本项目以青杨组杨树为模式植物,从形态和生理方面研究了来自不同UV-B背景下的康定杨与青杨在增强UV-B下的反应及其反应差异,并探讨了干旱、施肥对它们抗UV-B能力的影响。杨树具有分布广、适应性强、在生态环境治理和解决木材短缺方面均占有重要位置,研究成果可为生态系统的恢复与重建提供理论依据和科学指导。主要研究结果有以下: 1. 在温室中经过增强UV-B处理,杨树的外部形态及生理活动受到了一定程度的影响。增强UV-B导致康定杨、青杨的生物量、叶面积及节间长度降低,叶片增厚,SOD活性升高,膜伤害增加,而对叶片数目、R/S、叶绿素A、叶绿素B及整个叶绿素含量没有影响。两种杨树对UV-B胁迫的响应存在差异:在增强UV-B条件下,青杨的植株高度、生物量、叶面积、脯氨酸含量、长期用水效率受到的影响大于康定杨,相比而言,康定杨在比叶面积、叶片厚度、可溶性糖含量、UV-B吸收物质的含量及SOD和GPX活性方面增加的程度大于青杨。这些区别说明,来自于高海拔的康定杨比来自于低海拔的青杨对增强UV-B 具有更强的耐性。我们认为二者在叶片厚度、比叶面积、UV-B吸收物质含量及SOD、GPX活性差异是导致对增强UV-B耐性不同的原因。 2. 干旱与增强UV-B对杨树的生长和生理特性均产生了影响,而且两种胁迫共同作用时干旱表现减弱或加剧了UV-B对杨树某些形态和生理特性的影响。 据试验结果,干旱显著地降低了杨树的株高、叶片数目、叶面积,增加了叶片厚度,促进ABA的积累,提高了CAT活性。对于干旱,两种杨树之间也表现出了一定的差异性。可溶性蛋白质和脯氨酸在青杨叶片中得到显著积累,而在康定杨中没有变化。此外,CAT、长期用水效率在康定杨中受到的影响更加明显。长期用水效率的不同变化趋势说明两种杨树对水分胁迫采用了不同的用水策略,康定杨采用的是节水用水策略,提高用水效率,而青杨采用的是耗水的用水策略。根据干旱对叶面积、脯氨酸、ABA含量、CAT活性及长期用水效率等方面的影响,我们认为来自高海拔地区的康定杨比来自低海拔的青杨有更大的耐旱性,这是对生长环境长期适应的结果。在高海拔地区,因霜冻常带来土壤水分不可利用,降低了根系对水分的吸收,树木容易受到的生理性干旱。另外,高海拔的地区低的气温使植株对严寒有较强的耐性,减少了水分的需要。 生长于增强UV-B下的康定杨和青杨植株表现为高度降低,叶面积缩小,比叶面积增加;叶片栅栏组织、海绵组织均受到增强UV-B的影响,其厚度的增加导致整个叶片变厚。增强UV-B还显著提高了杨树的APX活性、UV-B吸收物质含量,而对叶片数目、ABA、可溶性蛋白质含量及CAT活性没有产生影响。试验中也观察到了两种杨树对增强UV-B响应的差异:与康定杨相比,在增强UV-B下青杨株高、叶面积降低的程度更大一些,SOD活性显著提高。另外UV-B吸收物质受到的影响不同。根据这些差别,高海拔的康定杨(3500 m)比来自低海拔的青杨(1500 m)增强UV-B有较强的耐性。 与水分充足情况下UV-B对植株的影响相比,干旱对杨树抗增强UV-B产生了一定的影响,表现为加剧或减弱UV-B对植物的影响,但这种影响与形态、生理指标有关。当干旱与增强UV-B共同作用时,杨树植株的株高、叶面积进一步降低、叶片进一步增厚。就脯氨酸的积累的而言,在没有水分胁迫时,增强UV-B促使它显著增加,而在干旱处理下这种效果变得不明显。干旱对增强UV-B的影响还与杨树的种类有一定的关系。在康定杨中,干旱减弱了增强UV-B对栅栏组织与海绵组织的影响,且在植株高度、叶面积上表现出累加效应,而在CAT上交互作用显著;但在青杨中干旱则加剧增强UV-B对栅栏组织与海绵组织的影响,在植株高度、叶面积及比叶面积上表现出显著的交互作用。据碳同素分析,在水分充足的条件下,无论是康定杨,还是青杨,增强UV-B均导致其长期用水效率的提高,然而当两种胁迫共同作用时,长期用水效率则表现出差异,在青杨中,长期用水效率得到进一步增高,而康定杨中干旱的效应被增强UV-B所减轻。 3. 田间试验表明,杨树的生长、生理特征都受到养分和增强UV-B的影响。施肥对杨树的影响表现为:提高了叶面积、生物量及SOD的活性,降低了抗坏血酸含量。对于施肥作用,两种杨树的反应也有区别:在康定杨中施肥显著增加了的叶片长度、宽度及光合色素的含量,降低了净光合速率、气孔导度及胞间CO2浓度;在青杨中,则SOD、GPX、APX活性表现增加。从试验看出,施肥对来自于高海拔地区的康定杨(3500 m)的影响较大,对来自低海拔的青杨(1500 m)影响较小,这与它们对原产地的生境适应有一定关系。在康定杨生长的高海拔地区,低温度和湿度不能为地上凋落物或土壤中的根分解提供理想的条件,造成当地土壤的低养分状况,所以当肥料施用以后,效果显著。 经过增强UV-B处理,杨树叶片中UV-B吸收物质含量、GPX的活性得到提高,而脯氨酸、丙二醛、可溶性蛋白质、叶绿素及类胡萝卜素含量没有受到影响。对于增强UV-B两种杨树受到的影响也有所不同:在青杨中增强UV-B导致叶面积缩小,生物量、净光合速率降低,APX的活性及长期用水效率的提高,而对康定杨的这些指标没有产生显著影响,相反抗氧化酶的活性明显高于青杨。这些差异性是由于两种杨树对原产地不同UV-B背景的长期适应结果。康定杨长期生长在较高UV-B环境中,对UV-B有较强的耐性。而青杨适应于较低的UV-B环境,对增强UV-B较为敏感。 试验中施肥也影响了植株对增强UV-B的反应,不过这种影响与杨树的种类及测定指标有一定的相关性。例如,在缺肥的情况下,青杨的长期用水效率和康定杨的叶绿素含量都受到增强UV-B的显著影响,而施肥以后这种影响变得不显著。在缺肥的条件下,GPX、APX在青杨中的活性、GPX在康定杨中的活性对增加UV-B反应不敏感;而施肥以后则变化显著,同样胞间CO2浓度在康定杨也有类似的变化。 For past decades, Ultraviolet radiation, especially UV-B reaching the Earth’s surface increased because of depletion of ozone layer resulted from emission of NxO and CFC’s from human activities. In this experiment, different species of Populus section Tacamahaca Spach from different UV-B background were selected as a model plant to assess the effects of enhanced UV-B radiation. Morphological and physiological traits induced by enhanced UV-B were observed and the different responses between P. kangdingensis and P. cathayana were discussed, furthermore the influences of drought and fertilizer on responses induced by enhanced UV-B were studied. Since poplars play an important role in lumber supply, and are important component of ecosystems due to their fast growth and wide adaptation, the study could provide a strong theoretical evidence and scientific direction for the afforestation, and rehabilitation of ecosystem. The results are as follows: 1. The experiment conducted in a greenhouse indicated that morphological and physiological traits of two poplars were affected by enhanced UV-B radiation. Enhanced UV-B radiation not only reduced biomass, leave area and internode length, but also increased leaf thickness and SOD activity as well as MDA concentration and electrolyte rate. However, no significant changes in leaf numbers, root shoot ratio, and total chlorophyll and chlorophyll component were observed. There were different responses to enhanced UV-B radiation between two species. Compared with P. kangdingensis, cuttings of P. cathayana, exhibited lower height increment and smaller leaf area. In addition, there were significant differences in free proline, soluble protein, and UV-B absorbing compounds, and the activity of SOD and GPX, long-term WUE between them. Differences in plant height, biomass, leaf area, free proline concentration, and long-termed WUE showed that P. cathayana were more affected by enhanced UV-B radiation than P. kangdingensis. In contrast, more increase of specific leaf mass, leaf thickness, and soluble sugar, and UV-B absorbing compounds, and activity of SOD and GPX were observed in P. kangdingensis. According to these results, we suggested that P. kangdingensis from high elevation, which adapted to higher UV-B environments, had more tolerance to enhanced UV-B than P. cathayana from low elevation, which adapted to lower UV-B environment. We believe it was the difference of leaf thickness, specific leaf mass, and UV-B absorbing compounds as well as the activity of SOD and GPX resulted in lower adaptation of P. cathayana to enhanced UV-B radiation. 2. Growth and physiological traits of two poplars were affected by both drought and enhanced UV-B radiation. Moreover, it was observed that when two stresses applied together drought could exacerbate UV-B effects or decrease sensitivity to UV-B. In the experiment, drought significantly decreased plant height, leaf numbers, leaf area, and increased leaf thickness, and ABA, and CAT activity of two poplars. There were significant interspecific differences to drought stress. Exposed to drought, soluble protein and proline concentration were increased in P. cathayana but not in P. kangdingensis. However, more changes in CAT and long-term WUE were observed in kangdingensis. Different change in long-term WUE suggests that two poplars adapted different water-use strategies. P. kangdingensis employ a conservative water-use strategy, whereas P. cathayana employ a prodigal water-use strategy. Based on the differences in leaf area, accumulation of free proline and ABA, CAT activity as well as long-term WUE, we believed that P. kangdingensis from high elevation had a greater tolerance to drought than P. cathayana from low elevation,which is the result of adaptation to local environment. In high elevation area, trees are prone to suffer from physiological drought because of un-movable water caused by frost. Besides lower temperature enable the plants had greater adaptability to frost as a results the requirement of water is reduced Enhanced UV-B radiation decreased shoots height, leaf area, and increased specific leaf mass and thickness of palisade and sponge layer as well as APX activity and UV-B absorbing compounds in both species. Whereas, leaf numbers, ABA content, soluble protein and CAT activity showed no differences to enhanced UV-B radiation. Interspecific differences were also observed. Compared with P. kangdingensis, P. cathayana showed lower shoot height and smaller leaf area, higher SOD activity. Besides, variation in UV-B absorbing compounds was found. These differences suggested that P. kangdingensis from high elevation (3500 m) was more tolerant to enhanced UV-B radiation than P. cathayana from low elevation (1500 m). Compared with morphological and physiological changes induced by enhanced UV-B radiation under well-watered conditions, drought exacerbated or decreased these changes. However, these effects vary with parameters measured. When two stresses applied together, shoot height and leaf area further decreased while leaf thickness further increased. Under well-watered conditions, enhanced UV-B radiation significantly increased proline content, but such effect was not observed under drought conditions. The effect of drought on enhanced UV-B radiation was related to species. For example, drought reduced the effects of enhanced UV-B radiation on palisade parenchyma and sponge mesophyll in P. kangdingensis, and additive effects in shoot height and leaf area and interactive effect CAT activity were observed. In contrast, for P. cathayana drought significantly exacerbated the effects of enhanced UV-B radiation on palisade parenchyma and sponge mesophyll; there were noticeable interaction in shoot height, leaf area and specific leaf mass. As far as long-term WUE is concerned, it was increased by enhanced UV-B radiation under well-watered conditions in both species. While different effect was observed between two species in combination of two stresses. Long-term water use efficiency was further increased in P. cathayana whereas the effect was less significant in P. kangdingensis. 3. The field experiment showed that growth and physiological traits of poplars were affected by nutrition and enhanced UV-B radiation. Fertilization significantly increased leaf area, biomass and SOD activity, reduced Ascorbic acid concentration. There was interspecific difference in response to fertilization. For P. kangdingensis, fertilization significantly increased leaf width, leaf length and photosynthetic pigments content while net photosynthetic rate and stomatal conductance, intercellular CO2 concentration were significantly decreased. However, for P. cathayana, these parameters were unaffected except the increase of SOD, GPX and APX activity. From above, it could concluded that P. kangdingensis from high elevation was more affected by fertilization than P. cathayana, This difference was due to adaptation to local environment., The low temperature and moisture where P. kangdingensis was collected can not provided optimum to decompose roots and litter fall as a result the nutrition in soil was poor. Exposed to enhanced UV-B radiation, for both species UV-B absorbing compounds and GPX activity were significantly increased while proline, MDA, soluble protein, chlorophyll, carotenoids were not affected. Different responses were also observed between the two species. Enhanced UV-B radiation caused significant decreases in leaf area, biomass, net photosynthetic rate and increase in APX activity and long-term WUE in P. cathayana but not in P. kangdingensis. In addition, activity in antioxidant enzymes was much higher in P. kangdingensis than in P. cathayana. In the experiment fertilization affected responses of cuttings to enhanced UV-B radiation, but it concern species and parameters measured. Long-term WUE in P. cathayana and chlorophyll in P. kangdingensis were significantly increased by enhanced UV-B radiation under non-fertilization treatments while the increase was not found under fertilization treatment. In contrast, under no fertilization treatment enhanced UV-B radiation did not affected GPX and APX activity in P. cathayana and GPX in P. kangdingensis while significant increase appeared after application of fertilization. Similar effect of enhanced UV-B radiation on intercellular CO2 concentration in P. kangdingensis was observed.

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小麦加工品质改良已成为我国小麦育种的主要目标之一。特别是我国加入WTO以后,对小麦产品的质量提出了更高的要求,小麦品质改良的任务将更加艰巨和重要,小麦胚乳蛋白是影响小麦加工品质性状的重要因素。因此,深入了解小麦胚乳蛋白对加工品质性状的影响及其分子基础,为品质改良提供理论依据和科学指导,对加速我国小麦品质育种和优质小麦生产具有重要意义。本研究选用在麦谷蛋白5个基因位点(Glu-A1、Glu-B1、Glu-D1、Glu-B3和Glu-D3)上均含不同等位基因的小麦品种99G45和京771及Pm97034和京771杂交F9代共164个麦谷蛋白纯合系,及228个中国推广普通小麦品种和高代育成品系为试材,研究了麦谷蛋白Glu-1和Glu-3位点基因等位变异对籽粒蛋白、湿面筋含量、Zeleny沉降值和SDS沉降值间的关系;本研究还利用小麦A、B和D基因组中低分子量麦谷蛋白亚基(LMW-GS)基因特异引物,通过PCR方法克隆了1个Glu-A3位点和3个Glu-B3位点LMW-GS基因片段,在此基础上分析了不同等位基因对品质造成差异的分子基础;另外,本研究对中国近年推广的部分品种和育成的高代品系资源的多样性进行了分析。现将主要研究结果简述如下: 1. 对来自三个麦区的148份材料的醇溶蛋白组成进行了分析,结果表明,各麦区醇溶蛋白模式具有较大差异。在ω区,A7、B、E、F、G、J、P、Q、S和U仅存在于西南秋播麦区;A3、M、N、R、W和X仅存在于黄淮特种麦区;K仅存在于北方冬麦区;A6是北方冬麦区出现频率最高的带型模式,而西南秋播麦区中D出现的频率最高。ω-区的E、H和M几种模式是以前国内外未曾报道的。且初步确定,这些模式对品质性状具有正效应。至于γ区,A、B、D、E和F在各区均有出现,其中B和E在各区出现的频率都很高,在26.1-39.6%之间。相反,H 仅出现在黄淮特种麦区,J仅限于西南秋播麦区。对于β-区醇溶蛋白,B型模式在所有区中都相当高,而模式A仅存在于第三区.对于α-区,模式A在Ⅲ区而模式D在Ⅱ区出现的频率很高。1BL.1RS易位系在中国小麦品种中出现频率高达41.2%,在I, II和Ⅲ麦区的出现频率分别为 45.5、43.5和35.2%。各生态区模式的差异可能是品种适应不同生态条件和人为选择的结果,但这有待进一步证明。由于醇溶蛋白位点(Gli-1)与LMW-GS位点(Glu-3)紧密连锁,本结果可为下面确定普通小麦LMW-GS等位基因变异所用。 2. 利用Gli-1与Glu-3的紧密连锁,以228个小麦品种/系为材料,首次对中国小麦品种麦谷蛋白亚基的6个位点进行综合分析,研究小麦籽粒蛋白与品质性状间的关系,结果表明6个高分子量(HMW)和低分子量(LMW)麦谷蛋白位点对蛋白质含量的效应大小为,Glu-D1>Glu-B3>Glu-A1=Glu-B1> Glu-A3=Glu-D3;对GMP含量的效应大小为, Glu-A3>Glu-B3>Glu-D1> Glu-B1>Glu-A1>Glu-D3;对湿面筋含量的效应大小为, Glu-B1>Glu-B3= Glu-D3>Glu-A3>Glu-A1>Glu-D1;对Zeleny沉降值的效应大小为, Glu-A1> Glu-B3>Glu-D3>Glu-D1>Glu-B1>Glu-A3;对SDS沉降值的效应大小为, Glu-B3>Glu-A1=Glu-D1=Glu-A3>Glu-D3>Glu-B1。对蛋白含量而言,各位点的最佳组合方式为1、17+18、5+10、Glu-A3e、Glu-B3g、Glu-D3b;对湿面筋含量而言,各位点的最佳组合方式为1、6+8、5+10、Glu-A3d、Glu-B3c、Glu-D3b;对Zeleny沉降值而言,各位点的最佳组合方式为N、17+18、5+10、Glu-A3d、Glu-B3d、Glu-D3b;对SDS沉降值而言,各位点的最佳组合方式为1、7+8、2.2+12、Glu-A3b、Glu-B3g、Glu-D3b。另外,分析了稀有亚基对5+12与2.2+12与品质性状的关系,认为5+12对品质有负效应,2.2+12对品质有正效应。在品质育种时,应对优异组合或优异亚基加以利用。 3. 首次利用重组自交系(RILs)为材料,研究麦谷蛋白亚基表达量与品质性状的关系,通过对重组自交系中各HMW-GS表达量的分析,认为,就单个亚基的表达量而言,7亚基最高;其次为2亚基、5亚基、12亚基和10亚基;亚基9和1的表达量最小;N亚基不表达。对成对出现的亚基对而言,x型和y型亚基的总表达量2+12>5+10>7+9>17+18。就单个亚基与品质性状的关系而言,仅有10亚基的表达量与蛋白含量的相关性达5%的显著水平,2亚基的表达量与湿面筋含量呈负相关,显著水平也达5%,其余单个亚基对品质性状均无显著影响;就x型/y型亚基的比例来看,2/12和5/10对湿面筋含量都有显著的负效应;对某一位点等位基因控制的亚基表达总量来看,2+12对SDS沉降值有显著负效应。另外,本研究得出:2+12的亚基对的负效应主要体现在2亚基上,且在同一位点上,x型亚基的表达量大于y型。所以推导稀有亚基组合2+10很可能也是劣质亚基。 4. 以 Glu-A1、Glu-B1、Glu-D1、Glu-B3和Glu-D3作为5个因素对99G45/京771和Pm97034/京771杂交后代的蛋白质含量和SDS沉降值进行多因素方差分析。结果表明,Glu-A1和Glu-D3对蛋白含量的加性效应达5%显著水平;Glu-D1 * Glu-D3对蛋白质含量的互作效应也达5%显著水平;其余位点的加性和互作效应对蛋白质含量的影响均不显著。对SDS 沉降值而言,Glu-D1的加性效应最大,贡献率为4.2 % ,达1 %显著水平,其次是Glu-B1位点,贡献率为3.3% ,达5%显著水平。其余位点对SDS 沉降值的加性和互作效应均未达5%显著水平。总体而言, 各位点对蛋白含量的效应大小为Glu-D3 > Glu-A1 > Glu-D1>Glu-B1>Glu-B3;对SDS沉降值的效应大小为Glu-D1>Glu-B1> Glu-D3>Glu-A1> Glu-B3。Glu-D1和Glu-D3位点上等位基因变异对蛋白含量有显著或极显著影响,含Glu-D1d和Glu-D3 GD、Glu-D3 JD基因的株系分别比含Glu-D1a和Glu-D3 PD基因的株系有较高的蛋白含量;在该遗传背景下,麦谷蛋白各基因位点对蛋白含量的效应大小依次排列为:Glu-A1位点1>N;Glu-B1位点7+9>17+18>14+15;Glu-D1位点5+10>2+12;Glu-B3位点GB>JB>PB;Glu-D3位点GB>JB>PB。对SDS沉降值的效应大小依次排列为:Glu-A1位点1>N;Glu-B1位点7+9=17+18>14+15;Glu-D1位点5+10>2+12;Glu-B3位点GB>JB>PB;Glu-D3位点GB>JB>PB。所以,对蛋白含量和SDS沉降值均较好的组合为1,7+9,5+10,GB,GD。 5. 因为GB和PB对品质的效应有显著差异,选取LMW-GS位点特异扩增引物对京771、99G45和Pm97034的Glu-B3位点进行扩增,结果得到三个不一样的扩增片段(Genebank号为DQ539657-DQ539659),得到的基因片段与Genebank中已报道的同类序列高度同源。通过克隆片段组成的分析,发现对Pm97034的序列较京771和99G45段少一个7氨基酸的重复单元,这可能是它较另外两个片段对面筋强度影响小的主要原因;另外,在99G45的序列中,124位处出现L(亮氨酸)代替P(脯氨酸),158位处出现了T(苏氨酸)代换M(蛋氨酸),这可能是99G45Glu-B3位点序列对SDS沉降值的效应显著优于Pm97034的原因。 6.通过对RILs各位点同普通小麦品种(系)各位点与品质关系的比较,发现对SDS沉降值的效应,各位点在不同研究材料中是不同的,普通小麦中:Glu-B3>Glu-A1=Glu-D1=Glu-A3>Glu-D3>Glu-B1,RILs中:Glu-D1>Glu-B1> Glu-D3>Glu-A1> Glu-B3。利用重组自交系材料(完全排除了1BL/1RS易位干扰)所得到的结果与Gupta and MacRitchie (1994)所得结论一致。进一步证实了1BL/1RS易位对小麦品质的重要影响。对蛋白含量而言,普通小麦品种(系)中,Glu-D1>Glu-B3>Glu-A1=Glu-B1> Glu-A3=Glu-D3,RILs中,Glu-D3 > Glu-A1 > Glu-D1>Glu-B1>Glu-B3,和对SDS沉降值的效应一样,推断在非1BL/1RS易位的情况下,各位点对其效应应为Glu-D3 > Glu-A1 > Glu-D1>Glu-B1>Glu-B3。 对同一位点的等位基因而言,普通小麦和重组自交系中Glu-A1和Glu-D1上的等位基因对品质性状的贡献是一致的,但Glu-B1上的等位基因对SDS沉降值的贡献发生了变化,普通小麦中17+18>7+9,RILs中7+9>17+18,这可能也是1BL/1RS造成的。 Baking quality improved is one of the main object of wheat bread in China. The overall objective of the present studies was to increase the understanding about protein quality in wheat, i.e. to make it possible to improve the production of wheat with desired quality for different end-uses. With the analysis of gluten protein in RILs, 99G45/Jing 771 and Pm97034/Jing, and 228 wheat cultivars or lines in China, the correlations between glutenin compositions and protein content, glutenin macropolymer(GMP), wet gluten content, Zeleny sedimentation value and SDS sedimentation value contentand breadmaking quality were studied. Also a rapid and efficient detection method of geneticpolymorphism at Glu-B3 loci in wheat was established using polymerase chain reaction(PCR).The results obtained were as follows: 1. Cultivated Chinese wheat germplasm has been a valuable genetic resource in international plant breeding. Patterns of gliadin among cultivated Chinese accessions are unknown, despite the proven value and potential novelty. The objective of this work was to analyse the diversity within improved Chinese wheat germplasm. The electrophoretic banding patterns of gliadin in common wheat cultivars and advanced lines were determined by acid-polyacrylamide gel electrophoresis. For 148 leading commercial cultivars and promising advanced lines used in our study, 48 patterns were identified, 29 corresponding to ω-gliadin, 9 to γ-gliadin, 5 to β-gliadin and 5 to α-gliadin. The most frequent patterns were A6 in ω; B in γ; B in β and A in the region of α. 116 band types appeared in the148 samples: 94 accessions had unique gliadin types, and 22 gliadin types while not unique were found in 54 accessions. The gliadin patterns of Chinese wheat cultivars and lines greatly differed from the patterns of wheat lines from other countries. Three patterns, E, J, H, M, N and O in the ω-zone had not previously been reported. Three wheat zones,the Northern Winter Wheat Region, the Yellow and Huai Valley River valleys Winter Wheat Region and the Southwestern Winter Wheat Region,in China showed different frequencies in their gliadin patterns. This information can be used to monitor genetic diversity with Chinese wheat germplasm. 2. To analyse the relationship between the loci and characteristics quality, we utilized the 228 cultivars/lines. The results showed that : For protein content, Glu-D1 >Glu-B3>Glu-A1=Glu-B1>Glu-A3=Glu-D3. For GMP content, Glu-A3>Glu-B3 >Glu-D1>Glu-B1>Glu-A1>Glu-D3. For wet gluten content, Glu-B1>Glu-B3= Glu-D3>Glu-A3>Glu-A1>Glu-D1. For Zeleny sedimentation value, Glu-A1>Glu-B3> Glu-D3>Glu-D1>Glu-B1>Glu-A3, For SDS sedimentation value, Glu-B3>Glu-A1= Glu-D1= lu-A3>Glu-D3>Glu-B1。For protein content, the best combination of 6 loci is (1,17+18,5+10,Glu-A3e, Glu-B3g,Glu-D3b). For wet gluten content, the best combination of 6 loci is (1,6+8,5+10,Glu-A3d,Glu-B3c,Glu-D3b). For Zeleny sedimentation value, the best combination of 6 loci is (N,17+18,5+10,Glu-A3d, Glu-B3d, Glu-D3b). For SDS sedimentation value, the best combination of 6 loci is(7+8,2.2+12,Glu-A3b, Glu-B3g,Glu-D3b)。Additional, we analysed the relationship between the subunits 5+12 and 2.2+12, think that 5+12 was negative for quality, 2.2+12 is postive for quality. It should be effective utilized. 3. It’s the first time to utilize RILs to study the relationship between subunits expression quantity and characteristics quality. The results showed that: For single subunit, the expression quantity of 7 is the highest. Then the 2, 5, 12 and 10. The expression of subunit 9 and 1 is the lowest. Subunit N is not expressed. For subunits, the expression quantity of x type and y type are 2+12>5+10>7+9>17+18. The significant relation of 5% only showed between the expression quantity of subunit 10 and protein content. The relationship between expression quantity of others and characteristic quality was not significant. For x type/ytype, 2/12 and 5/10 is negative relation insignificant level. For the subunit(s) in a loci, Only 2+12 effect SDS sedimentation value negative in significant level. 4. With RILs 99G45/Jing 771 and Pm97034/Jing 771, we found that: The effective of Glu-A1, Glu-D3 and Glu-D1 * Glu-D3 for protein content is significant at 5% level. The effect of other loci for protein wre not significant. For SDS sedimentation value, the effect of Glu-D1is the highest, which contribution is 4.2 % .Then the Glu-B1, contribution is 3.3%. The effect of other loci for SDS sedimentationvalue were not significant. In total, for protein content: Glu-D3 > Glu-A1 > Glu-D1>Glu-B1>Glu-B3; for SDS sedimentationvalue: Glu-D1>Glu-B1> Glu-D3>Glu-A1>Glu-B3. The effect of alleles in Glu-D1 and Glu-D3 loci are significant at 1% or 5%. In Glu-A1, 1>N; Glu-B1, 7+9>17+18>14+15; Glu-D, 5+10>2+12; Glu-B3, GB>JB>PB; Glu-D3, GB>JB>PB. For SDS sedimentation, Glu-A1, 1>N; Glu-B1, 7+9=17+18>14+15; Glu-D1, 5+10>2+12; Glu-B3, GB>JB>PB; Glu-D3, GB>JB>PB. The best combinations for SDS sedimentation value is 1,7+9,5+10,GB,GD. 5. Because of the difference of GB and PB for SDS sedimentation value, we selected the specific primer for LMW-GS loci to amplified the Glu-B3 of Jing771, 99G45and Pm97034. We got 3 amplify fragment (Gene Bank accession number are DQ539657-DQ539659). We found that the fragment of Pm97034 were deleted a repetitive 7 amino acid domain, which is perhaps the reason effect the gluten strength. Furthermore, in the position 124 of sequence 99G45, L has been replaced with P. Position 158, T replaced M, which may be the reason why the Glu-B3 locus of 99G45 is prefer to Pm97034 when refer to SDS sedimentation value. 6. Comparing the results of RILs and common wheat, we found that perhaps just the1BL/1RS made the difference of loci in different accession.

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青稞,是我国藏区居民对裸大麦的称谓,它不仅是藏民的主要食粮、燃料和牲畜饲料,而且也是啤酒、医药和保健品生产的原料;青稞不仅为藏区人民的健康和经济发展做出了很大的贡献,而且对人类健康和社会经济的可持续发展都有重要的意义。青藏高原是我国及世界上青稞分布和种植面积最大的地区,资源极其丰富。虽然从经典遗传直到分子标记对我国大麦遗传多样性都有研究,但研究手段、数量仍然不够深入,对我国大麦资源遗传多样性研究的信息非常有限,不能很好地满足大麦遗传研究和育种应用的需要,尤其是对西藏栽培大麦的遗传多样性的研究还只是刚刚开始,关于栽培青稞多态性的研究报道很少。本研究采用SSR标记和蛋白质电泳两类技术,从SSR标记位点、单体醇溶蛋白、B组醇溶蛋白和淀粉粒结合蛋白(SGP)等四个方面对我国青藏高原栽培青稞的遗传多样性进行了综合评价。 SSR标记具有基因组分布广泛、数量丰富、多态性高、容易检测、共显性、结果稳定可靠、实验重现性好、操作简单、经济、易于高通量分析等许多优点,被认为是用于遗传多样性、品种鉴定、物种的系统发育、亲缘关系及起源等研究的非常有效的分子标记。本研究采用SSR标记分析了64份青藏高原栽培青稞的遗传多样性,同时评估SSR标记在我国大麦育种和品种鉴定中的应用潜力。选择了30个已知作图位点SSR标记,其中25个标记与重要性状的控制位点连锁紧密。选择的30个SSR标记,5个未得到很好的扩增产物,3个无多态性。22个多态性SSR标记位点中,每位点检测出等位基因2~15个,共检测出等位基因132个,平均每位点6.0 个。各多态位点检测出基因型为2~11种,位点HVM33的基因型最多。各多态位点的多态信息指数为0.16~0.91, 平均为0.65。根据PIC值选择了13个SSR标记用于我国青藏高原栽培青稞基因型鉴定,这些标记的PIC值为0.6以上。结合PIC值和基因型差异,选择了8个多态信息含量高的SSR标记,构建了高效指纹图谱,此图谱能把64份材料完全区分。 贮藏蛋白电泳分析是研究相关编码蛋白基因多态性的非常有效的方法。大麦单体蛋白与小麦醇溶蛋白相对应,具有丰富的多态性,可用于大麦遗传多样性、品种鉴定和群体进化等研究。本研究通过A-PAGE电泳技术研究了84份青藏高原栽培青稞的单体醇溶蛋白多态性。大麦单体醇溶蛋白图谱与小麦醇溶蛋白电泳图谱类似,所分离的蛋白清晰地分为ω-,γ-,β-和α-四个部分。青藏高原栽培青稞单体醇溶蛋白具有丰富的多态性,84份青稞材料中存在43条不同的蛋白带,75种组合带谱;其中67种为单一材料所独有,另8种则分别包含了2-3份材料。每份材料中拥有醇溶蛋白带为6-16条,含有6-10条单体醇溶蛋白带材料较多。西藏和四川材料群体单体醇溶蛋白多态性不同,具有区域特异性。西藏材料中发现了40条不同蛋白带,3条特异带,46 种蛋白组合;四川材料中出现了40种不同蛋白带,26种条带组合, 3条特异带。基于单体蛋白多态性的聚类与材料的来源有一定的相关性。A-PAGE单体蛋白具有丰富的多态性,可作为遗传研究和品种鉴定的标记。 大麦醇溶蛋白(hordein)是大麦籽粒的主要贮藏蛋白,与大麦的营养品质和加工品质密切相关,而且具有丰富的多态性,广泛用于品种鉴定、种质筛选、遗传多样性和亲缘关系研究。B组醇溶蛋白是主要的醇溶蛋白组份,约占总醇溶蛋白的80%,而且具有丰富的多态性。本研究采用SDS-PAGE分析了72份青藏高原栽培青稞B组醇溶蛋白的遗传多样性。青藏高原栽培青稞B组醇溶蛋白具有丰富的多态性,72份青稞材料中存在15种蛋白带,30种组合带谱,其中15种为单一材料所独有,另15种则分别包含了2-10份材料。每份材料中B组醇溶蛋白条带数为4-8条,含5、6条的材料较常见。不同来源的群体材料间B组醇溶蛋白组成存在差异,西藏青稞含有26种蛋白组合带谱,其中有19种特异带谱;四川群体中共发现11种蛋白组合带型,其中有4种特有带谱。两群体中都存在稀有条带。聚类分析将材料分成三组,材料聚类与材料来源地没有明显的相关性。 淀粉粒蛋白(Starch granule proteins, SGPs)是一类与淀粉粒结合的微量蛋白,一些淀粉粒蛋白具有淀粉生化合成中主要的酶蛋白功能,其变异会影响淀粉含量和特性,从而影响淀粉的应用。关于我国大麦淀粉粒组成研究还未见报道。本实验首次开创了我国大麦淀粉粒结合蛋白的研究工作。采用SDS-PAGE电泳技术研究了青藏高原栽培青稞的SGP组成,并分析了不同SGP组合间淀粉含量的差异,初步探索了所分离的SGP蛋白与淀粉合成的关系。66份青稞材料中分离了10种主要的SGP,其表观分子量为40-100KD,低于60KD的SGP带有7条,共有16种组合带谱;各SGP蛋白和组合带谱出现的频率存在差异,青藏高原青稞的SGP组成存在多态性。西藏青稞和四川青稞的SGP组成有很大差异,SGP组成具有地域差异性,西藏青稞含有12种蛋白组合带谱,其中有9种特异带谱;四川群体中共发现7种蛋白组合带型,其中有4种特有带谱;两群体中仅有3种共同的蛋白组合带谱。SGP蛋白特性将66份青稞分为三组, 即Ⅰ、Ⅱ、Ⅲ,材料聚类与材料来源具有一定的相关性。不同组合带谱材料间淀粉含量差异显著性检验结果显示,不同带谱间材料的总淀粉含量、直链淀粉含量和支链淀粉含量有差异,带谱2(SGP1+3+7+9+10)和8(SGP1+2+4+6+8)的总淀粉含量及支链淀粉含量显著大于组合带谱3(SGP1+3+7+10)的总淀粉含量。组合带谱7(SGP1+2+6+8)的直链淀粉含量显著低于带谱11(SGP1+5+8)的直链淀粉。带谱SGP2、3、4、5、6、7、8、9、10可能参与淀粉合成,SGP9可能与高支链淀粉的合成相关。 SSR标记位点、单体醇溶蛋白、B组醇溶蛋白、淀粉结合蛋白等四个方面的研究结果表明青藏高原SSR标记多态性、单体醇溶蛋白多态性、B组醇溶蛋白多态性和SGP多态性都非常丰富,与青藏高原是栽培青稞的多样性分布中心的观点一致。 青藏高原栽培青稞的SSR标记、单体醇溶蛋白、B组醇溶蛋白和SGP多态性表现出很大差异。SSR标记覆盖了整个基因组,多态性非常高。单体蛋白、B组醇溶蛋白、SGP蛋白是育种中非常关注的性状,他们只是代表基因组中的某一区域或位点,多态性相对较低。但单体蛋白多态性很高,84份材料中检测出43条不同蛋白带,75种不同的组合带谱。SSR标记技术和单体蛋白技术都是遗传多样性研究的有力工具,但单体蛋白技术不仅多态性高,而且经济、操作简便,是种质鉴定的理想方法。 对不同标记的多态性材料数据进行聚类,聚类图能为我们提供各材料间的遗传相似信息,为材料选择提供参考。但材料聚类与材料来源的地理区域的相关性表现不一致。SSR聚类和B组醇溶蛋白聚类与材料的来源地无相关性,而单体醇溶蛋白和SGP聚类与材料来源地有一定相关性,即西藏群体和四川群体分别有集中类群,这可能是人为选择的附加效应。 不同来源的群体材料的遗传多样性不同,具有区域特异稀有基因,加强不同地区间资源的交换和配合使用,有利于增加群体遗传多样性和新品种培育。 青藏高原栽培青稞的麦芽浸提性状、淀粉性状、病虫及裸粒等重要农艺性状控制位点存在丰富的变异,遗传基础宽广,可能蕴藏着多种不同的等位基因,是研究重要性状遗传特性、基因资源挖掘和遗传育种的宝贵资源库。 Hulless barley, due to its favorable attributes such as high feed value, good human nutrition,rich dietary fiber and ease processing, attracts people,s attention . Hulless barley plays a very important role in Tibetan life, used as essential food crop, main animal feed and important fuel. In addition to tsampa (roasted barley flour), a main food for Tibetan, hulless barley is also made into cake, soup, porridge, recent naked barley liquor and cornmeal. Qinghai-Tibet Plateau is one of a few areas which plant naked barley widely in the world and also has a long growing history. Genetic diversity of the cultivated hulless barley in this region , however, has not been documented. The study of genetic diversity existing within this population is of particular interest in germplasm identification, preservation, and new cultivar development. This study analyzed the genetic diversity of the cultivated naked barley from Qinghai-Tibet plateau through the study of SSR marker loci and monomeric prolamins, B-horden and starch granule proteins. SSRs are present abundantly in genomes of higher organisms and have become a popular marker system in plant studies. SSRs offer a number of advantages, such as the high level of polymorphisms, locus specificity, co-dominance, reproducibility, ease of use through PCRand random distribution throughout the genome. In barley, several hundred SSRs have been developed and genetically mapped and can therefore be selected from specific genomic regions. The genetic diversity of 64 cultivated naked barley from Tibet and Sichuan was studied with 30 SSRs of known map location.Among the selected SSR markers, PCR products of 5 SSR markers were not obtained and 3 SSR marker loci were monomeric. A total of 132 alleles were identified at 22 polyomeric SSR loci. The number of alleles per locus ranged from 2 to 15, with an average of 6.0. The polymorphism information content values for the SSRs ranged from 0.08 to 0.94, with an average of 0.65. 13 SSR markers with the PIC value >0.6 have been selected for discrimination of Qinghai-Tibet naked barley genotypews. A finger Print map was developed through 7 SSR markers with the high PIC value. It could be used as an efficient tool for gene discovery and identification of gernplasm. Hordeins, the main storage proteins of the barley seed, are composed of momomeric and polymeric prolamins and divided into -A, B, C and D groups in order of decreasing electrophoretic mobility. Hordeins show high inter-genotypic variation and have been extensively used as markers for cultivar identification and analyzing the genetic diversity. This study analyzed the genetic diversity of B-hordein in 72 naked barley from Qinqhai-Tibet Plateau. Extensive diversity was observed. A total of 15 different bands and 30 distinct patterns were found. Jaccard's coefficient of similarity was calculated, and the accessions were divided into three main groups by cluster analysis using UPGMA. Differentiation among the populations from different collecting regions based on the polymorphism of B-hordein was investigated. Monomeric prolamins show high inter-genotypic variation and have been used as molecular markers for cultivar identification, analyzing the genetic diversity in collections and investigating the evolution processes and structure of populations However, the cultivated hulless accessions from Qinghai-Tibet Pateau in China have never been examined with respect to monomeric prolamins. This study analyzed the genetic diversity of monomeric prolamins (protein fraction corresponding to wheat gliadins) using the Acid -PAGE technique in eighty-four cultivated hulless barley from Qinqhai-Tibet Plateau in China. Extensive diversity was observed. A total of 43 different bands were found, of which 21 different bands were in the region of ω group, 8 in the region of γ, 8 in the region of β, and 6 in the region of α group. Among the 86 accessions, 75 distinct patterns were identified. The number of bands ranged from 6 to 16, depending on the variety. Jaccard’s coefficient of similarity was calculated, and the lines were grouped by cluster analysis using UPGMA. A dendrogram was obtained from the analysis of the groups and five main clusters were identified. No relationship between the distribution in the dendrogram and growth habits and origins of the cultivars could be detected. Starch is the major constituent of the cereal endosperm, comprising approximately 65% of the dry weight of the mature wheat grain. The starch formed in all organs of plants is packaged into starch granules, which vary widely between species and cultivars in size and shape. Wheat endosperm starch granules contain about corresponding to the main biosynthase of starch. This report firstly dealed with intraspecific variation of the major SGPs in cultivated naked barley from Qinghai-Tibet plateau. A total of 10 major SGPs were observed in the range of 40KD-100KD and 16 types of patterns were found. Based on the variation of SGPs, accessions studied were classified into 3 groups. A geographical cline of electrophoregram was observed. In addition, significance test of the difference of starch content among groups and types of patterns were done, and the results indicated those SGPs could be related to the content of starch. Diagram obtained through cluster analysis exhibited a structuration of diversity and genetic relationship among cultivated hulless accessions. In breeding program, parents with genetically distant relationship for hybridization will increase genetic diversity of progenies. In conclusion, cultivated naked barley from Qinghai-Tibet Plateau in China presents a high variability with respect to monomeric prolamins,SSR markers , B- hordeins and SGPs. The result of this study supports Qinghai-Tibet Plateau is the center of cultivated hulless barley and the cultivated naked barley is considered to be a gene pool with large diversity and could be applied to breeding for cereal.

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用能量为140MeV的27Al束流轰击145Nd氧化靶,通过145Nd(27Al,4nγ)168Ta熔合蒸发反应对双奇核168Ta的高自旋态进行了实验研究.扩展了基于πh11/2νi13/2和π5/2+[402]ν5/2+[642]准粒子组态下的转动带能级纲图.根据实验测量结果,对两转动带的准粒子顺排特征作了分析.通过B(M1)/B(E2)的理论与实验值比较以及168Ta相邻双奇核能级间隔系统性,进一步确定了两转动带的准粒子组态和能级的自旋宇称.

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Molar heat capacities of ibuprofen were precisely measured with a small sample precision automated adiabatic calorimeter over the temperature range from 80 to 400 K. The polynomial functions of C-p,C-m (J K-1 mol(-1)) versus T were established on the heat capacity measurements by means of the least fitting square method. The functions are as follows: for solid ibuprofen, at the temperature range of 79.105 K less than or equal to T less than or equal to 333.297 K, C-p,C-m = 144.27 + 77.046X + 3.5171X(2) + 10.925X(3) + 11.224X(4), where X = (T - 206.201)/127.096; for liquid ibuprofen, at the temperature range of 353.406 K less than or equal to T less than or equal to 378.785 K, C-p,C-m = 325.79 + 8.9696X - 1.6073X(2) - 1.5145 X-3, where X = (T - 366.095)/12.690. A fusion transition at T = 348.02 K was found from the C-p-T curve. The molar enthalpy and entropy of the fusion transition were determined to be 26.65 kJ mol(-1) and 76.58 J mol(-1) K-1, respectively. The thermodynamic functions on the base of the reference temperature of 298.15 K, (H-T - H-298.15) and (S-T - S-298.15), were derived. Thermal characteristic of ibuprofen was studied by thermo-gravimetric analysis (TG-DTG) and differential scanning calorimeter (DSC). The temperature of fusion, the molar enthalpy and entropy of fusion obtained by DSC were well consistent with those obtained by adiabatic calorimeter. The evaporation process of ibuprofen was investigated further by TG and DTG, and the activation energy of the evaporation process was determined to be 80.3 +/- 1.4 kJ mol(-1). (C) 2003 Elsevier B.V. All rights reserved.

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A comprehensive study on physical and chemical properties of Mo/MCM-22 bifunctional catalysts has been made by using combined analytic and spectroscopic techniques, such as adsorption, elemental analysis, and Xe-129 and P-31 NMR of adsorbed trialkylphosphine oxide probe molecules. Samples prepared by the impregnation method with Mo loadings ranging from 2-10 wt.% have been examined and the results are compared with that obtained from samples prepared by mechanical mixing using MoO3 or Mo2C as agents. Sample calcination treatment is essential in achieving a well-dispersed metal species in Mo/MCM-22. It was found that, upon initial incorporation, the Mo species tend to inactivate both Bronsted and Lewis sites locate predominantly in the supercages rather than the 10-membered ring channels of MCM-22. However, as the Mo loading exceeds 6 wt.%, the excessive Mo species tend to migrate toward extracrystalline surfaces of the catalyst. A consistent decrease in concentrations of acid sites with increasing Mo loading < 6 wt.% was found, especially for those with higher acid strengths. Upon loading of Mo > 6 wt.%, further decreases in both Bronsted and Lewis acidities were observed. These results provide crucial supports for interpreting the peculiar behaviors previously observed during the conversion of methane to benzene over Mo/MCM-22 catalyst under non-oxidative conditions, in which an optimal performance was achieved with a Mo loading of 6 wt.%. The effects of Mo incorporation on porosity and acidity features of the catalyst are discussed. (C) 2004 Published by Elsevier B.V.

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在碳酸氢铵(下称普通碳铵)生产过程中,定量加入一种有机化合物DCD(下称氨稳定剂),形成共结晶型新肥种,称之为长效碳酸氢铵(下称长效碳铵)。其特点是:减缓直接挥发损失率47%;肥效期由35~45d延长到90~110d;氮素利用率提高5.9~10.2个百分点;在同等产量水平下可节肥20%~30%;在等氮量施肥条件下增产率为10%,常显示出有促进作物早熟功能。可作基肥1次施入,为免中耕、覆膜和节水农业提供了节约劳力而增产的肥料。

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以两性霉素B抗性作为标记 ,通过单株灭活 ,进行栖土曲霉种内非营养缺陷型原生质体融合 .在 40 %的PEG(Mr=6 0 0 0 )促融下 ,融合频率为 1.6 2× 10 -5.连续传接 10代后 ,获得稳定的融合子 .对孢子体积、核DNA含量、生长速度进行了测定 ,并利用RAPD技术分析比较了亲本及融合子的基因组DNA指纹多态性 ,证明融合子为杂合二倍体 ,产角蛋白酶活力较亲本显著提高 .图 3表 4参 17

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一、 药物滥用是一种慢性、复发性脑疾病。药物滥用将导致药物成瘾(addiction),其主要表现有药物依赖、药物耐受、药物敏感化以及药物停用后的戒断症状(withdraw symptom)。药物成瘾的核心特征是强迫性觅药和用药行为。药物成瘾会导致药物滥用者认知功能的损伤和认知偏差,并会造成滥用者情绪异常。药物成瘾是一个复杂的生物学过程,有着及其复杂的机理。对药物成瘾机制的解释有很多种,主要认为成瘾过程是一种学习记忆过程,学习记忆的机制在药物成瘾过程中起到了非常重要的作用。首先,学习记忆和药物成瘾过程都受到了相似的神经营养因子以及神经递质系统的调控,例如:它们都受cAMP,CREB等调控因子的调控。其次,研究发现与成瘾相关的线索,如用药有关的人物、地点或暗示等,在药物戒断很长时间后都会恢复吸毒者的用药行为。并且,当把与成瘾相关的线索呈现给毒品戒断中的人时,这些人会出现心率、呼吸加快,血压升高等现象,甚至表现出明显的渴求行为。药物对学习记忆的影响是复杂的,虽然重复使用药物会导致药物成瘾,并且这个过程需要学习记忆机制的参与,但同时使用吗啡却会对其他类型的学习记忆(如:恐惧性学习记忆、一次性被动回避学习记忆和水迷宫空间学习记忆)造成破坏。学习前给予吗啡可以剂量及状态依赖地破坏被动回避试验以及空间辨别试验的记忆获取过程。学习过程结束后立即给予吗啡可以破坏一次性被动回避试验、主动回避试验和恐惧条件化试验的记忆巩固过程。测试前给予吗啡可以破坏空间辨别试验的记忆提取过程。本研究的目的在于更进一步地了解使用吗啡导致吗啡成瘾以及使用吗啡导致学习记忆的各个阶段受损的机制。为此我们采用了药理学以及多种行为学的方法,1、用PTZ诱发的癫痫持续状态干扰吗啡成瘾的学习记忆过程,进一步比较了吗啡成瘾的学习记忆与其他学习记忆,例如:空间学习记忆以及食物奖赏学习记忆的机制有何异同;2、研究了β-肾上腺素系统与阿片系统在空间记忆巩固过程中的相互作用;3、我们还研究了NMDA受体的激动剂和拮抗剂在吗啡破坏空间记忆提取过程中的作用。研究结果发现: 1.戊四唑诱发的癫痫持续状态,对吗啡建立的条件化位置偏好没有任何影响,动物仍然对阳性箱(吗啡匹配箱)表现出明显的偏好。但是癫痫持续状态破坏了食物建立的条件化位置偏好,并且还破坏了水迷宫和Y迷宫检测的空间记忆。癫痫持续状态破坏了食物建立的条件化位置偏好,原因不是由于其影响了动物的食欲。此外,癫痫持续状态也没有持续地破坏动物的活动能力,因此,对动物活动量的影响也不是造成其他学习记忆破坏的原因。这些结果说明,吗啡成瘾的学习记忆和普通的学习记忆在机制上可能存在不同之处。为了说明这个问题,我们还需要进行其他更深入的研究。 2、训练后立即单独注射吗啡(0.25和2.5 mg/kg)或心得安(2,10和20 mg/kg)都不会破坏动物Y-迷宫空间记忆的巩固过程,动物仍然能识别新异环境,并在里面停留较长时间。但是,训练后同时注射吗啡和心得安却可以破坏动物空间记忆的巩固过程。并且,较高剂量的吗啡(2.5 mg/kg)加上较高剂量的心得安(10和20 mg/kg)对记忆的破坏更严重,实验组动物在新异环境停留的时间显著低于对照组。这说明阿片系统和去甲肾上腺素系统在破坏记忆巩固的过程中可能有协同作用。 3、记忆提取前30分钟注射吗啡(1和10 mg/kg)可以剂量依赖地破坏Y-迷宫空间记忆的提取。单独注射NMDA受体的激动剂NMDA(1,2和4 mg/kg)对动物的空间记忆提取没有影响,但是,单独注射NMDA受体拮抗剂MK-801(0.05,0.1和0.2 mg/kg)剂量依赖地破坏了空间记忆的提取。同时注射吗啡(10 mg/kg)和NMDA(2 mg/kg)可以阻断吗啡对空间记忆造成的破坏作用。相反,共同注射吗啡(1 mg/kg)和MK-801(0.05 mg/kg)可以加重吗啡对空间记忆造成的破坏作用。这说明谷氨酸系统可以干扰吗啡对记忆提取过程的影响。 二、衰老严重地影响了人们的视觉功能,然而眼睛光学系统的老年性改变并不能完全解释清楚这种视觉功能衰退。一般认为是神经系统的退化导致了这种老年性功能降低。但是,研究显示视网膜(retina)和外膝体(dorsal lateral geniculate nucleus, dLGN)在衰老的过程中神经元的数量和体积以及神经元的功能特性,如对比度敏感性、空间分辨率等,都没有明显的变化,因此,人们推测老化导致的神经系统的变化发生在更高级的视觉皮层。过去几年的研究发现老年动物视觉皮层细胞发生了一系列反应特性的改变,如:老年动物皮层细胞的方向选择性和方位选择性降低以及细胞反应的潜伏期延长。这些细胞水平的变化被认为是老年性视觉功能衰退的神经机制。为了更全面地了解衰老过程对视觉皮层的影响以及细胞反应改变与整体功能降低之间的关系,本研究采用活体动物细胞外单位记录的方法,比较了青年和老年猕猴初级视觉皮层细胞时间反应特性和空间反应特性的差异。研究结果发现:老年动物初级视觉皮层细胞的时间频率和空间频率敏感性明显比年轻动物降低。表现为老年动物初级视觉皮层细胞的最优时间和空间频率、空间分辨率(spatial resolution, SR)和较高时间截至频率(high temporal frequency cut-off, TF50)都显著低于年轻动物初级视觉皮层细胞,同时伴随着这些功能的降低,老年动物初级视觉皮层细胞的自发放增加,对视觉刺激的反应增加,但是信噪比却显著降低。这些结果表明,老年动物初级视觉皮层细胞的功能在老化过程中都普遍降低。这可能是导致老年人视觉功能降低的原因。

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A universal metal-molecule-metal sandwich architecture by the self-assembly of Ag nanoparticles (NPs) and Au NPs of various shapes interconnected with 4-aminothiophenol (4-ATP) molecules was presented. These Ag NPs/4-ATP/Au NPs sandwich structures were characterized by surface enhanced Raman scattering (SERS) using an off-surface plasmon resonance condition. Enhancement factors (EF) on the order of 10(8) for 9b(b(2)) vibration mode were observed for the 4-ATP self-assembled monolayers (SAMs) in such sandwich structures. The factors are 2 orders of magnitude larger than that on the monolayer of Au NPs of various shapes under similar condition. More importantly, remarkable increase in the intensity of b(2) vibrational modes, which is characteristic of the charge transfer (CT) behavior between metal NPs and 4-ATP molecules, was observed in these sandwich structures under 1064 nm excitation. The obtained EF on these sandwich structure for 9b(b(2)) is larger than that for 7a vibration mode by a factor of similar to 10(2), demonstrating the importance of the contribution of the CT mechanism and the CT behavior of metal contacts, which play a significant role in metal-molecule-metal nanosystems.

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Surface-enhanced Raman scattering (SERS) activity of silver-gold bimetallic nanostructures (a mean diameter of similar to 100 nm) with hollow interiors was checked using p-aminothiophenol (p-ATP) as a probe molecule at both visible light (514.5 nm) and near-infrared (1064 nm) excitation. Evident Raman peaks of p-ATP were clearly observed, indicating the enhancement Raman scattering activity of the hollow nanostructure to p-ATP. The enhancement factors (EF) at the hollow nanostructures were obtained to be as large as (0.8 +/- 0.3)x10(6) and (2.7 +/- 0.5)x10(8) for 7a and 19b (b(2)) vibration mode, respectively, which was 30-40 times larger than that at silver nanoparticles with solid interiors at 514.5 nm excitation. EF values were also obtained at 1064 nm excitation for 7a and b(2)-type vibration mode, which were estimated to be as large as (1.0 +/- 0.3)x10(6) and (0.9 +/- 0.2)x10(7), respectively. The additional EF values by a factor of similar to 10 for b(2)-type band were assumed to be due to the chemical effect. Large electromagnetic EF values were presumed to derive from a strong localized plasmas electromagnetic field existed at the hollow nanostructures.

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New neutral nickel(II) complexes bearing nonsymmetric bidentate pyrrole-imine chelate ligands (4a-d), [2-(ArNCH)C4H3N]Ni(PPh3)Ph [Ar=2,6-diisopropylphenyl (a), 2-methyl-6-isopropylphenyl (b), 2,6-diethylphenyl (c), 2-tert-butylphenyl (d)], have been prepared in good yields from the sodium salts of the corresponding ligands and trans-Ni(PPh3)(2)(Ph)Cl, and the structure of complex 4a has been confirmed by X-ray crystallographic analysis. These neutral Ni(II) complexes were investigated as catalysts for the vinylic polymerization of norbornene. Using modified methylaluminoxane (MMAO) as a cocatalyst, these complexes display very high activities and produce great mass polymers. Catalyst activity of up to 4.2 x 10(7) g (mol Ni h)(-1) and the viscosity-average molecular weight of polymer of up to 9.2 x 10(5) g mol(-1) were observed. Catalyst activity, polymer yield, and polymer molecular weight can be controlled over a wide range by the variation of reaction parameters such as Al-Ni ratio, norbornene-catalyst ratio, monomer concentration, polymerization reaction temperature and time.

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A new compound, [Ni(en)(3)](2)[Ni(en)(2)(H2O)(2)][As6V15O42] . 4H(2)O, was first prepared by hydrothermal synthesis and characterized by elemental analysis, IR, TGA-DSC, ESR and single crystal X-ray diffraction. Crystal data: monoclinic, space group C-c, a = 1. 523 6(3) nm, b = 2. 051 8(4) nm, c = 2.395 9(5) nm, beta = 97. 41(3)degrees, V = 7.427(3) nm(3), Z = 4, R = 0. 057 0, wR(2) = 0.135 7. The polyanion consists of six AsO3 pyramids and fifteen VO5 pyramids. Counterions are complex ions with octahedral structure, which consist of NH2CH2CH2NH2 and Ni2+.

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The title heteropoly blue, (Bu4N)(6)H-10 [(PMo11MoO40)-Mo-VI-O-V](4) . H2O has been photochemically synthesized and characterized with elemental analysis, solid diffusion reflectance electronic spectra, CV, ESR, XPS, IR spectra, conductivity measurement and X-ray single crystal analysis. The crystallographic data for C96H218Mo48N6O169P4 are as follows: M-r = 8889.76, triclinic, P (1) over bar, a = 1.4142 (3) nm, b = 2.6027 (5) nm, c = 2.6403(5) nm, alpha = 113.96(3)degrees, beta = 90.05(3)degrees, gamma = 105.71(3)degrees, V = 8.481 (3) nm(3), Z = 1, D-c = 1.741 g/cm(3), F (000) = 4264, mu = 1.798 mm(-1). The X-ray crystal structure analysis reveals that there Is one independent molecule in the unit cell of the title heteropoly blue which contains four mixed-valence heteropoly anions, six tetrabutylammonium cations and one water molecule. Its molecular structure possesses a centrosymmetrical arrangement in the unit cell. The phosphorus atom is In the crystallographic inversion center of the heteropoly anion and the eight oxygen atoms surrounding central phosphorus atom comprise of a distorted hexahedron. Heteropolyanion has two equal sets of PO4 tetrahedron. The PO4 tetrahedron and the MoO6 octahedron in the polyanion are greatly distorted.

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The block copolymer polystyrene-b-poly[2-(trimethylsilyloxy)ethylene methacrylate] (PSt-b-PTMSEMA) was synthesized using atom-transfer radical polymerization (ATRP). The hydrolysis of PSt-b-PTMSEMA led to the formation of an amphiphilic block copolymer, polystyrene-b-poly(2-hydroxylethyl methacrylate) (PSt-b-PHEMA), which was characterized by GPC and H-1-NMR. TEM showed that the PSt-b-PHEMA formed a micelle, which is PSt as the core and PHEMA as the shell. Under appropriate conditions, the nickel or cobalt ion cause chemical reactions in these micelles and could be reduced easily. ESCA analysis showed that before reduction the metal existed as a hydroxide; after reduction, the metal existed as an oxide, and the metal content of these materials on the surface is more than that on the surface of the copolymer metal ion. XRD analysis showed that the metal existed as a hydroxide before reduction and existed as a metal after reduction.