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941.
基于26个微卫星标记的三江水系草鱼遗传多样性分析 总被引:2,自引:2,他引:2
选取26个微卫星标记对来自长江(监利、邗江)、黑龙江、珠江3个水系的4个野生草鱼(Ctenopharyngodon idellus)群体的遗传多样性进行了检测。结果表明,26个微卫星位点均为高度多态位点,草鱼4个地理群体的多态信息含量(PIC)平均值为0.581 3~0.638 6;共检测出141个等位基因,其中有102个为共有等位基因;每个位点有等位基因2~11个,平均等位基因5.46,平均有效等位基因3.455 6。4个地理群体野生草鱼的平均杂合度在0.711 4~0.804 5之间。群体间遗传固定指数(FST)及AMOVA分析表明,群体间遗传分化并不显著(FST=0.031 73)。基于DA遗传距离构建的UPGMA聚类树表明,监利群体与邗江群体这两个长江水系野生地理群体聚为一支,然后与珠江群体聚为一支,黑龙江群体单独聚为一支。长江群体是原始群体。综上所述,三江水系野生草鱼具有较高的遗传多样性,4个群体之间遗传分化并不明显。 相似文献
942.
Eun Ju Cho Do Jin Lee Chi Do Wee Hong Lim Kim Yong Hwa Cheong Ju Sik Cho Bo Kyoon Sohn 《Scientia Horticulturae》2009,122(4):633-637
We aimed to investigate the effects of inoculating Panax ginseng C.A. Meyer seedlings with arbuscular mycorrhizal fungi (AMF) by examining the root colonization, plant nutrition uptake, growth characteristics, and soil aggregation of P. ginseng seedlings inoculated at the time of transplantation. At 16 weeks, the AMF spore density per 30 g of fresh mycorrhizosphere in seedlings inoculated with AMF (AMF+ seedlings) was 256.8 and that in seedlings not inoculated with AMF (AMF− seedlings) was 186.3, respectively. The colonization rate of AMF in the lateral roots of AMF+ seedlings was approximately 19% higher than that in the lateral roots of AMF− seedlings. The patterns of AMF colonization in ginseng roots were similar to those of the Paris-type mycorrhizal association. Plant growth characteristics, such as plant height, root length, leaf area, number of lateral roots, fresh weight of shoots and roots, and chlorophyll content, were significantly enhanced in AMF+ seedlings compared to AMF− seedlings. The macronutrient content (P, K, and Ca) and micronutrient content (Cu, Fe, and Zn) of both shoots and roots were also significantly higher in AMF+ seedlings compared to AMF− seedlings. Furthermore, glomalin content and soil aggregation were significantly enhanced in AMF inoculated areas. Our results indicate that AMF inoculation may enhance the growth of ginseng seedlings by improving the uptake of mineral nutrients and the soil structure in mycorrhizosphere. 相似文献
943.
银杏锰型超氧化物歧化酶GbMnSOD基因的克隆与表达 总被引:2,自引:0,他引:2
利用RACE技术首次从银杏中克隆到锰型超氧化物歧化酶基因(GbMnSOD ) 的cDNA全长。GbMnSOD的cDNA全长965 bp (GenBank accession number: EF633506) 。生物信息学分析GbMnSOD cDNA序列含有一个681 bp最大读码框, 编码一个226氨基酸多肽链, 通过软件预测分子量为2515 kD, 等电点为8197。三维结构预测结果显示, GbMnSOD 含有12个α螺旋和3 个β折叠构成一个篮子状的活性中心。GbMnSOD氨基酸序列与其它植物MnSOD具有很高的相似性。进化树分析结果表明GbMnSOD和其他物种的MnSOD源自于相同的祖先。Southern杂交显示, GbMnSOD属于一个小的多基因家族。Northern 杂交表明GbMnSOD在银杏的根、茎、叶和果中都有表达, 在叶中的表达量最高, GbMnSOD 的转录受到ABA、IAA、蔗糖、甘露醇、NaCl 和低温的诱导。 相似文献
944.
AIM:To investigate the key molecular mechanism of inflammatory response in alveolar epithelial cells induced by nontypeable haemophilus influenzae (NTHi). METHODS: A549 cells were co-cultured with NTHi (multiplicity of infection, MOI: 10) and harvested 15 min and 30 min after stimulation. The phosphorylation of p38 mitogen activated protein kinase (p38 MAPK) in A549 cells was detected by Western blotting. The intracellular expression of nuclear factor-κB (NF-κB) p65 was examined by flow cytometry 4 h after stimulation. A549 cells were preincubated with p38 inhibitor (SB203580) or NF-κB inhibitor (PDTC) for 1 h and then stimulated with NTHi for 24 h. The level of interleukin 8 (IL-8) in the supernatants was determined by enzyme-linked immunosorbent assay (ELISA). RESULTS: The phosphorylation of p38 MAPK was rapidly induced by NTHi stimulation. The expression of NF-κB p65 in A549 cells after NTHi stimulation was significantly up-regulated compared with control group (P<0.05). The level of IL-8 in the supernatants was increased 24 h after bacterial stimulation compared with control group (P<0.05). Blockage of p38 MAPK or NF-κB remarkably decreased IL-8 secretion in A549 cells (P<0.05). CONCLUSION:NTHi induces inflammatory response in alveolar epithelial cells in a p38 MAPK and NF-κB dependent manner. 相似文献
945.
AIM:To study the effect of adiponectin (APN) on lipid peroxidation in human umbilical vein endothelial cells (HUVECs) induced by hydrogen peroxide (H2O2) in vitro.METHODS:The effect of H2O2 on apoptosis was measured by flow cytometry with Annexin V-FITC labeling.The concentration of malonaldehyde (MDA) in HUVECs was detected by thiobarbituric acid (TBA) method.The activities of superoxide dismutase (SOD) and catalase (CAT) were measured by colorimetric assay.The scavenging rate on superoxide anion radicals in xanthine oxidase system and OH radicals produced by Fenton reaction were also tested.RESULTS:APN significantly inhibited H2O2-induced apoptosis.H2O2 increased MDA production and reduced the activities of SOD and CAT, which were inhibited by APN.APN did not alter the activities of SOD and CAT in normal condition.APN dose-dependently decreased the superoxide anion radicals, with the scavenging rate of 11.9%, 21.4%, 36.9%,respectively, and scavenged OH radicals.CONCLUSION:APN inhibits apoptosis and protects endothelial cells against lipid peroxidation insult by scavenging the free radicals. 相似文献
946.
AIM: To illustrate the effects of overexpression of stathmin 1 on melanocyte growth and the relationship between C terminal motif and stathmin 1 function.METHODS: The overexpression vector and C terminal mutant coding vector were constructed. The vectors were transfected into melanocytes by Lipofectamine 2000. MTT and FCM were used to inspect the cell growth, Western blotting was a tool in caspase-3 measurement, and spectrophotography was used to detect the melanin products and tyrosinase activity.RESULTS: The vectors of overexpression and mutation were constructed and transfected into melanocytes successfully. Both of them inhibited the melanocyte growth, induced apoptosis, and decreased the melanin products and tyrosinase activity.CONCLUSION: Overexpression of stathmin 1 inhibits melanocyte growth, melanin products and tyrosinase activity. The change of C terminal motif could not affect the role of stathmin 1 in melanocyte markedly. 相似文献
947.
Logging pattern and landscape changes over the last century at the boreal and deciduous forest transition in Eastern Canada 总被引:4,自引:0,他引:4
Forestry practices associated with the industrial era (since ~1900) have altered the natural disturbance regimes and greatly
impacted the world’s forests. We quantified twentieth century logging patterns and regional scale consequences in three sub-boreal
forest landscapes of Eastern Canada (117,000, 49,400 and 92,300 ha), comparing forestry maps depicting age and forest cover
types for early industrial (1930) and present-day (2000) conditions. Results were similar for the three landscapes, indicating
large-scale forest change during the twentieth century. In 1930, previous logging activities had been concentrated in the
lowlands and along the main hydrographical network, as compared to a more even distribution over the landscapes in 2000, reflecting
a decreasing influence of the environmental constraints on forest harvesting. In 1930, old-aged forests (>100 years) accounted
for more than 75% of the unlogged areas of the three landscapes, as compared to less than 15% for the present-day conditions.
Logging practices have thus inverted the stand age distribution of the landscapes that are currently dominated by young and
regenerating stands. The 1930 forest cover types showed a clear relationship with elevation, with conifers located in the
lowlands and mixed and deciduous stands restricted to the upper slopes. Between 1930 and 2000, 58–64% of the conifer areas
transformed to mixed and deciduous forests, such that no clear altitudinal relationships remained in 2000. We conclude that
twentieth century logging practices have strongly altered the preindustrial vegetation patterns in our study area, to the
point that ecosystem-based management strategies should be developed to restore conifer dominance, altitudinal gradients,
as well as the irregular structure inspired from old forest stands. 相似文献
948.
AIM: To observe the effects of carvedilol on murine viral myocarditis model. METHODS: A total of 188 inbred male BALB/c mice of 4-6 weeks were divided into 4 groups: myocarditis group (group C, n=60), metoprolol treatment group (group M, n=60), carvedilol treatment group (group K, n=60), control group (group B, n=8). Myocardial histopathololgic changes were observed. The concentrations of cardiac troponin I (cTn-I) were detected by chemiluminescence immunoassay (CLIA). Western blotting was performed to analyze the contents of phosphorylated p38MAPK in myocardium. RESULTS: Metropolol and carvedilol lightened myocardial histopathololgic changes at acute stage, decreased cTn-I concentrations and myocardial phosphorylated p38MAPK value compared with myocarditis group. Treatment with carvedilol was more effective than treated with metropolol on those indexes. CONCLUSION: Carvedilol protects against viral myocarditis by inhibition of p38MAPK signal transduction pathway through blockade of β1 and β2 adrenergic receptors. 相似文献
949.
Effects of fruit bagging on coloring and related physiology,and qualities of red Chinese sand pears during fruit maturation 总被引:1,自引:0,他引:1
Chunhui Huang Bo Yu Yuanwen Teng Jun Su Qun Shu Zaiquan Cheng Liqiong Zeng 《Scientia Horticulturae》2009
Red Chinese sand pears (Pyrus pyrifolia Nakai) are particular to China. In order to determine the effects of fruit bagging treatments (including bag types, bag removal patterns and dates) on fruit qualities and to understand the mechanism of coloring of red Chinese sand pears, two experiments were carried out. In the first experiment, fruit of ‘Meirensu’ were firstly covered by light-impermeable paper bags with different levels of light permeable liners during their early development stage, then, the whole bag were/not removed or only the outer layer of bags were removed 3, 2 or 1 weeks before harvest. Thus, the fruit were/not totally re-exposed or were under different levels of sunlight transmission (80.31% or 34.71%). Non-bagged fruit were used as the control. Bagging treatments significantly affected the concentration of anthocyanin and the visual qualities of pear fruit. Compared to control, fruit re-exposed totally for 2 or 3 weeks accumulated the largest amount of anthocyanin and fruit receiving 80.31% and 34.71% of sunlight for 1–3 weeks could synthesize a little anthocyanin, indicating that high light intensity is imperative for coloring in red Chinese sand pears. Bagging treatments did not affect contents of total soluble sugars, but decreased organic acids contents in fruit. In the second experiment, fruit of ‘Meirensu’ and ‘Yunhongli No. 1’ were covered with only one type of light-impermeable bag during the early development stage and totally re-exposed after the bag removal 15 days before harvest. Fruit were then collected at different intervals to trace the time-course of coloring, and related physiology and inner qualities. With increasing time after the bag removal, the concentration of chlorophyll, carotenoid, flavonoid and total phenols changed little, but the concentration of anthocyanin accumulated extremely fast within 10 days after the bag removal in both cultivars and thereafter kept constant. ‘Yunhongli No. 1’ had higher anthocyanin contents and lower hue angle than ‘Meirensu’, indicating a higher potential of anthocyanin synthesis. After the bag removal, the sucrose contents and PAL activities increased gradually and correlation analysis revealed that they were highly correlated with anthocyanin accumulation in two cultivars. This study suggests that anthocyanin biosynthesis in red Chinese sand pears is a highly light dependent process and modified by genotypes. Based on the current results, in order to obtain red Chinese sand pear fruit with attractive appearance and good inner qualities, fruit must be covered with light-impermeable bags at the early stage of fruit development and the bag should be removed totally at least 10 days before harvest. 相似文献
950.
黄瓜游离小孢子培养诱导成胚和植株再生 总被引:4,自引:0,他引:4
以10个不同基因型黄瓜为试材进行游离小孢子培养,通过对成胚条件的系统研究,从‘7447’和‘Poinsett97’中获得了子叶形胚和再生植株。研究结果表明:基因型和小孢子发育时期是限制黄瓜游离小孢子成胚的关键因子。不同品种间胚状体产量差异显著,每皿产胚1.5~33.4个。单核靠边期是进行黄瓜游离小孢子培养的最佳时期。低温预处理有利于胚状体的诱导,4 ℃预处理2~4 d为宜,以处理2 d时胚状体产量最高。外源激素在诱导胚状体时并非必需,但低浓度的外源激素(0.5 mg·L-1 2,4-D、0.2 mg·L-1 6-BA)更能促进小孢子成胚。NLN和B5两种基础培养基在诱导胚状体上无显著差异。子叶形胚易分化成苗,而其它类型的胚状体不能获得再生植株。 相似文献