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91.
[目的]研究野燕麦原生质体的制备与融合方法.[方法]用机械法制备野燕麦的原生质体,并用PEG结合高Ca2+-高pH溶液的融合法对原生质体的融合进行研究.[结果]野燕麦叶片在35%蔗糖溶液中质壁分离15 min能够制备数量较多的原生质体;PEG结合Ca2-高pH融合法能有效地使野燕麦原生质体融合.[结论]该技术为植物叶片细胞原生质体的制备与融合奠定了基础. 相似文献
92.
在对转录组和蛋白组数据联合分析的基础上,通过RT–PCR方法克隆得到沙芥幼苗叶片2个小分子热激蛋白基因PcHSP26.5和PcHSP17.8,运用生物信息学软件分析它们的核苷酸和编码蛋白,通过Real–time PCR分析其在高温、低温、NaCl、ABA和干旱复水胁迫下的表达模式。PcHSP26.5和PcHSP17.8开放阅读框分别为699 bp和462 bp,分别编码282和153个氨基酸,其中PcHSP26.5包含1个内含子。PcHSP26.5、PcHSP17.8的相对分子质量分别为26 480、17 490,理论等电点分别为6.36、5.99;均无跨膜结构与信号肽位点,属于亲水蛋白。亚细胞定位预测和进化树分析表明,PcHSP26.5主要定位于线粒体中,属于MⅡ亚族;PcHSP17.8主要定位于细胞质中,属于CⅠ亚族。实时荧光定量PCR结果表明:高温胁迫下,沙芥PcHSP26.5和PcHSP17.8基因的相对表达量均在1 h达到顶峰,之后下降;低温胁迫下,沙芥PcHSP26.5基因的相对表达量在0.5 h达到顶峰,之后下降,沙芥PcHSP17.8基因的相对表达量在0.5~12 h内低于对照,24 h时出现上升趋势;NaCl胁迫下,沙芥PcHSP26.5和PcHSP17.8基因的相对表达量分别在 1 h和3 h达到顶峰,之后下降;ABA胁迫下,沙芥PcHSP26.5和PcHSP17.8基因的相对表达量均在2 h达到顶峰,之后下降;干旱复水胁迫下,沙芥PcHSP26.5和PcHSP17.8基因的相对表达量均在干旱9 d达到顶峰,复水后下降。 相似文献
93.
鹿流行性出血病毒是一种在全世界野生及驯养的有蹄动物中广泛存在的重要病原体.该病毒属呼肠病毒科环状病毒属,有12个血清型,是一种有10个节段(L1-L3、M4-M6、S7-S10)的双链RNA病毒,编码10个蛋白(VP1-7和NS1、NS2、NS3/NS3A).VP7蛋白具有很强的抗原性且保守性最高.VP2与病毒型特异性有关,可诱导产生中和抗体.VP3为群特异性抗原,高度保守,具有亲水性保守区域.非结构蛋白NS1、NS2和NS3/NS3A及其编码序列均相当保守.该病毒的分子生物学诊断技术主要有PCR和核酸探针杂交技术. 相似文献
94.
95.
以小麦面粉为原料,研究了淀粉共生蛋白对淀粉酶解性质的影响。对洗淀粉过程中影响蛋白含量的条件进行了单因素试验,用SDS溶液和蛋白酶进一步除去淀粉中的蛋白质成分,然后对制得的含氮量不同的淀粉样品进行酶解。试验结果表明,蛋白酶能有效地去除淀粉共生蛋白,而淀粉共生蛋白有助于淀粉的水解。 相似文献
96.
97.
Shelton GD Liu LA Guo LT Smith GK Christiansen JS Thomas WB Smith MO Kline KL March PA Flegel T Engvall E 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2001,15(3):240-244
The most common form of muscular dystrophy in dogs and humans is caused by mutations in the dystrophin gene. The dystrophin gene is located on the X chromosome, and, therefore, disease-causing mutations in dystrophin occur most often in males. Therefore, females with dystrophin deficiency or other forms of muscular dystrophy may be undiagnosed or misdiagnosed. Immunohistochemistry was used to analyze dystrophin and a number of other muscle proteins associated with muscular dystrophy in humans, including sarcoglycans and laminin alpha2, in muscle biopsy specimens from 5 female dogs with pathologic changes consistent with muscular dystrophy. The female dogs were presented with a variety of clinical signs including generalized weakness, muscle wasting, tremors, exercise intolerance, gait abnormalities, and limb deformity. Serum creatine kinase activity was variably high. One dog had no detectable dystrophin in the muscle; another was mosaic, with some fibers normal and others partly dystrophin-deficient. A 3rd dog had normal dystrophin but no detectable laminin alpha2. Two dogs could not be classified. This study demonstrates the occurrence of dystrophin- and laminin alpha2-associated muscular dystrophy and the difficulty in clinical diagnosis of these disorders in female dogs. 相似文献
98.
应用逆转录套式PCR检测新城疫病毒核酸 总被引:7,自引:1,他引:6
选择DNV融合蛋白保守的编码区域,设计并合成了一对外引物和一对内引物,建立并优化了检测新城疫病毒核酸的逆转录套式PCRI地,通过检测NDV感染的实验客观存在病料和临床病料,结果表明,逆转录套式PCR法最低能鉴别出约0.3pg的NDV RNA,攻毒后第8天还能从非免疫鸡和SPF鸡泄殖腔拭子中检出DNV,第8天非免疫鸡泄殖腔拭子中NDV的最大检出率为5/10,第8天SPF鸡泄殖腔拭子中NDV的最大检出率为6/10,对非免疫鸡和SPF鸡的泄殖腔中NDV最佳检出时间均在攻毒后第5天。逆转录套式PCRY应运地临床样品中DNV的最大检出率为6/7,经核酸杂交验证,该法具有很高的特异性和敏感性,也比较简便快速,为从分子水平探讨NDV的发病机理、临床早期快速诊断提供了新的研究手段。 相似文献
99.
Effects of foliar- and root-applied silicon on the enhancement of induced resistance to powdery mildew in Cucumis sativus 总被引:3,自引:0,他引:3
Two cucumber ( Cucumis sativus ) cultivars differing in their resistance to powdery mildew, Ningfeng No. 3 (susceptible) and Jinchun No. 4 (resistant), were used to study the effects of foliar- and root-applied silicon on resistance to infection by Podosphaera xanthii (syn. Sphaerotheca fuliginea ) and the production of pathogenesis-related proteins (PRs). The results indicated that inoculation with P. xanthii significantly suppressed subsequent infection by powdery mildew compared with noninoculation, regardless of Si application. Root-applied Si significantly suppressed powdery mildew, the disease index being lower in Si-supplied than in Si-deprived plants, regardless of inoculation treatment. The resistant cultivar had a more constant lower disease index than the susceptible cultivar, irrespective of inoculation or Si treatment. Moreover, with root-applied Si, activities of PRs (for example peroxidase, polyphenoloxidase and chitinase) were significantly enhanced in inoculated lower leaves or noninoculated upper leaves in inoculated plants of both cultivars. Root-applied Si significantly decreased the activity of phenylalanine ammonia-lyase in inoculated leaves, but increased it in noninoculated upper leaves. However, Si treatment failed to change significantly the activity of PRs in plants without fungal attack. Compared to the control (no Si), foliar-applied Si had no effects either on the suppression of subsequent infection by P. xanthii or on the activity of PRs, irrespective of inoculation. Based on the findings in this study and previous reports, it was concluded that foliar-applied Si can effectively control infections by P. xanthii only via the physical barrier of Si deposited on leaf surfaces, and/or osmotic effect of the silicate applied, but cannot enhance systemic acquired resistance induced by inoculation, while continuously root-applied Si can enhance defence resistance in response to infection by P. xanthii in cucumber. 相似文献
100.
Inoculation of nonhost pepper ( Capsicum annuum ) plants with the tomato wilt pathogen, Fusarium oxysporum f.sp. lycopersici (FOL), caused no symptoms and the fungus was not recovered from any part of the plant. FOL, however, partially protected pepper plants from subsequent infection with Phytophthora capsici , Verticillium dahliae or Botrytis cinerea by significantly reducing the percentage of diseased plants and the appearance and intensity of symptoms. FOL did not inhibit the mycelial growth of these pathogens in vitro . The protection induced by FOL against Botrytis was inhibited by 1-methylcyclopropene (MCP), an inhibitor of ethylene perception, suggesting the involvement of this hormone in the signalling of FOL-induced resistance. The activities of β-1,3-glucanase and peroxidase 48 h after FOL induction were similar to those in control plants. Chitinase activity, however, was higher in the stems of plants inoculated with FOL. A study of the levels of phenolic compounds revealed that cell-wall-bound phenolics were more abundant in plants treated with FOL, especially in stems, while soluble phenolic contents did not differ. 相似文献