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61.
大豆灰斑病抗性遗传的三点测交分析 总被引:1,自引:0,他引:1
本实验利用三点测交分析的方法, 对3个组合在人工接种大豆灰斑病菌的条件下的抗性表现进行基因效应分析,各组合均存在加性,组合1存在显性,组合2、3存在上位性。
Abstract:In this paper,Triple Test Cross Design was used in studing the resistance of soybean to 10 physiological race of Cercospora Sojina Haraby inoculation.Results o analysis of gene effects of resistance indicated that additive effect is significant in all the three crosses,dominant effect exsists only in the cross 1 and epistatic effect remains in the cross 2 and cross 3. 相似文献
62.
Alignment of 23 branching enzyme (BE) amino acid sequences from various species showed conservation of two arginine residues. Phenylglyoxal (PGO) was used to investigate the involvement of arginine residues of maize BEI and BEII in catalysis. BE was significantly inactivated by PGO in triethanolamine buffer at pH 8.5. The inactivation followed a time- and concentration-dependent manner and showed pseudo first-order kinetics. Slopes of 0.73 (BEI) and 1.05 (BEII) were obtained from double log plots of the observed rates of inactivation against the concentrations of PGO, suggesting that loss of BE activity results from as few as one arginine residue modified by PGO. BE inactivation was positively correlated with [14C]PGO incorporation into BE protein and was considerably protected by amylose and/or amylopectin, suggesting that the modified arginine residue may be involved in substrate binding or located near the substrate-binding sites of maize branching enzymes I and II.Abbreviations BE
branching enzyme
- BCA
bicinchoninic acid
- BSA
bovine serum albumin
- Glc-1-P
glucose-1-phosphate
- IPTG
isopropyl-d-thiogalactoside
- PGO
phenylglyoxal
- PMSF
phenylmethylsulfonyl fluoride
- SDS-PAGE
sodium docecyl sulfate-polyacrylamide gel electrophoresis
- TCA
trichloroacetic acid
- TEA
triethanolamine 相似文献
63.
64.
应用MUCAP试剂快速检测沙门氏菌 总被引:5,自引:0,他引:5
报告了用4-甲基伞形酮辛酯(4-Methylumbelliferyl-caprylate, MUCAP)快速检测沙门氏菌的特异性、敏感性和实用性。经HE,DHL,SS和麦康凯琼脂平板分离的65株沙门氏菌标准菌株和48株从食品中分离的沙门氏菌,用MUCAP测试均呈阳性反应;394株非沙门氏菌中呈阳性反应的假单胞菌、气单胞菌、邻单胞菌可通过氧化酶试验与沙门氏菌区分开;与粘质沙雷氏菌的交叉反应改用加1%蔗糖的分离平板也可排除。此方法的敏感性和特异性均达到97%以上,而且操作简便、快速,数分钟内即可完成。 相似文献
65.
Identification, mapping, and application of polymorphic DNA associated with resistance gene Pm21 of wheat. 总被引:34,自引:0,他引:34
A new powdery mildew resistance gene designated Pm21, from Haynaldia villosa, a relative of wheat, has been identified and incorporated into wheat through an alien translocation line. Cytogenetic and biochemical analyses showed that chromosome arms 6VS and 6AL were involved in this translocation. Random amplified polymorphic DNA (RAPD) analysis was performed on recipient wheat cultivar Yangmai 5, the translocation line, and H. villosa with 180 random primers. Eight of the 180 primers amplified polymorphic DNA in the translocation line, and the same results were obtained in four replications. Furthermore, RAPD analysis was reported for substitution line 6V, seven addition lines (1V-7V), and the F1, as well as F2 plants of (translocation line x 'Yangmai 5'), using two of the eight random primers. One RAPD marker, specific to chromosome arm 6VS, OPH17-1900, could be used as a molecular marker for the detection of gene Pm21 in breeding materials with powdery mildew resistance introduced from H. villosa. Key words : RAPD analysis, 6VS-specific marker, Pm21, Erysiphe graminis f.sp. tritici, Triticum aestivum - Haynaldia villosa translocation. 相似文献
66.
We have broadly defined the DNA regions regulating esterase6 activity in
several life stages and tissue types of D. melanogaster using P-
element-mediated transformation of constructs that contain the esterase6
coding region and deletions or substitutions in 5' or 3' flanking DNA.
Hemolymph is a conserved ancestral site of EST6 activity in Drosophila and
the primary sequences regulating its activity lie between -171 and -25 bp
relative to the translation initiation site: deletion of these sequences
decrease activity approximately 20-fold. Hemolymph activity is also
modulated by four other DNA regions, three of which lie 5' and one of which
lies 3' of the coding region. Of these, two have positive and two have
negative effects, each of approximately twofold. Esterase6 activity is
present also in two male reproductive tract tissues; the ejaculatory bulb,
which is another ancestral activity site, and the ejaculatory duct, which
is a recently acquired site within the melanogaster species subgroup.
Activities in these tissues are at least in part independently regulated:
activity in the ejaculatory bulb is conferred by sequences between -273 and
-172 bp (threefold decrease when deleted), while activity in the
ejaculatory duct is conferred by more distal sequences between -844 and
-614 bp (fourfold decrease when deleted). The reproductive tract activity
is further modulated by two additional DNA regions, one in 5' DNA (-613 to
-284 bp; threefold decrease when deleted) and the other in 3' DNA (+1860 to
+2731 bp; threefold decrease when deleted) that probably overlaps the
adjacent esteraseP gene. Collating these data with previous studies
suggests that expression of EST6 in the ancestral sites is mainly regulated
by conserved proximal sequences while more variable distal sequences
regulate expression in the acquired ejaculatory duct site.
相似文献
67.
复方克痛宁临床应用镇痛效果 总被引:3,自引:0,他引:3
应用复方克痛宁注射液,治疗各种痛证82例,显效50%,有效43.9%,总有效率93.9%。其中大多数病例都是经用其它药或疗法无效或效差而用本药获效的。对关节痛、神经血管性头痛等顽固性疼痛显著独特。用药次数最少1次,最多35例,仅极个别有轻微短暂口干、头晕副作用,各项常规化验检查均无异常,效果显著高于克痛宁或盐酸平痛新单用。临床应用的结果与动物试验观察到的协同增效结果一致。 相似文献
68.
丙型肝炎病毒基因组部份NS5区蛋白基因在大肠杆菌中的表达 总被引:1,自引:0,他引:1
在大肠杆菌中表达了丙型肝炎病毒基因组NS5区A段和部份B段蛋白。NS5A蛋白溶于水,可经过GST亲和层析柱纯化;NS5B蛋白不溶于水,经PBS-Triton X-100洗涤,尿素溶解后,通过离子交换柱纯化。经SDS-PAGE和Westemblot分析,NS5A蛋白除在57kD左右有条带外,还有不同程度的降解产物;NS5B蛋白主要在58kD左右有条带出现。为查明表达蛋白抗体在病人血清中的分布,取9 相似文献
69.
本文将昆明地区11-15岁健康儿童90名按不同的口腔条件分为三组,每组30人。采用培养基表面主培养主数法,分别测定唾液中厌氧菌和需氧菌细菌总数。结果表明:儿童唾液中细菌总数,牙颌畸形组、正畸组、正常组,三组间结果在统计学无显著差异。 相似文献
70.