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番茄五个品种的核型研究(摘要) 总被引:1,自引:0,他引:1
本文研究了番茄五个不同品种(武昌大红、加拿大、佛特、荷兰五号、青北早)的核型。1.番茄的核型公式如下: (1) 武昌大红。2n=24=2M+8m+12sm+2st (2) 加拿大。2n=24=4M+8m+12sm (3) 佛特。2n=24=2M+8m+10sm+4st (4) 荷兰五号2n=24=2M+14m+8sm (5) 青北早2n=24=4M+8m+12sm 2、五个品种中都具有一对随体染色体,但位于那一对染色体上也有相同和相异。“武昌大红”与“佛特”的随体在第9对上。“加拿大”在第7对上。“荷兰五号”及“青北早”位于第4对染色体上,并发现“武昌大红”、“加拿大”品种的随体,在同一品种也出现随体大小的差异。3、在各个品种中,染色体的全长、相对长度、臂比都存在着一些差异。4、对于番茄染色体的随体的大小及其在染色体对数的位置,染色体的形态结构,核形与番茄起源的关系进行了初步讨论。 相似文献
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曾子申;胡峻;利容千 《武汉植物学研究》1985,3(4):439-442
本文对我国栽培辣椒Capsicum annuum L.的四个品种即汉川椒、华椒一号、牛角椒和二金条进行了核型分析,其染色体数目均为2n=2x=24,核型公式均为2n=24=20m+2sm+2st,但汉川椒和华椒一号具一对随体,牛角椒和二金条具两对随体。本文还对它们的进化关系进行了讨论。 相似文献
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近年来,常用未经丙酮固定的、由丁酸和巴豆油激活的B95-8细胞或P3HR-1细胞为靶细胞,检测人血清中EB病毒IgA/MA抗体以早期诊断鼻咽癌,效果良好。但由于B95-8细胞含有多种EB病毒抗原,不能用丙酮固定,需多次离心沉淀,在浮悬状态下检测,技术比较复杂。 相似文献
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用改进的LiCl沉淀法和寡聚(dT)-纤维素亲和层析法由猪垂体制得总mRNA。在兔网织红细胞无细胞翻译体系中进行体外翻译的结果表明,制得的总mRNA具有一定的翻译活力。翻译产物与兔抗猪生长激素抗血清发生免疫沉淀,沉淀物占总翻译产物的10%左右。SDS聚丙烯酰胺凝胶电泳的结果表明翻译产物有一条很深的带,分子量约为24,000道尔顿,与猪前生长激素的分子量相近。以制备的mRNA为模板反转录合成了双链cDNA。第一链的合成产率为10—35%,第二链的合成产率为84—115%。cDNA的平均分子长度为825bp。 相似文献
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通过过聚乙二醇6000-磷酸钾缓冲液双相分离、Sephadex G-100凝胶过滤、DEAE-Sephadex A-50离子交换层析、羟基磷灰石层析及SephadexG-100凝胶过滤等提纯步骤,从海枣曲霉(Aspergillus phoenicis)麦麸培养物抽提液中提纯得到凝胶电泳均一的β-半乳糖苷酶。该酶的最适pH为3.5—4.0,最适温度为60℃(反应15分钟),在pH5.0—8.5之间及60℃以下稳定。在65℃和70℃保温时失活50%的时间分别为27和2分钟。用SDS凝胶电泳法和梯度凝胶电泳法分别测得该酶的分子量为115,000和118,000。薄层凝胶等电聚焦法测得其等电点为pH4.6。 相似文献
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M. C. GACULA JR. R. W. WASHAM II S. A. BEARD J. E. HEINZE 《Journal of sensory studies》1986,1(1):47-53
In-house use consumer test data from four studies dealing with three pairs of household products and a pair of antiperspirant products were examined for significant carry-over (product usage order) effects, which would confound the analysis of treatment (product) effects. In each study, two products were compared using a two-period crossover design. One hundred twenty panelists participated in each study. A forced choice preference scale or a 9-point hedonic scale was used to obtain responses from various sensory attributes. In all studies, the estimates of carry-over effects were not significant at the 5% level. Transformation of hedonic scale data into preference dichotomy also gave estimates of carry-over effects which were not significant at the 5% level, but led to a loss of test sensitivity for detecting treatment differences. The authors recommend that all comparative crossover design studies in sensory evaluation be monitored for carry-over effects and that statistically determined sample size should be used to reduce the possibility of obtaining significant carry-over effects. 相似文献
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The ontogeny of strombid behavior was studied by observing thebehavior of Strombus maculatus veligers collected from the planktonand reared past metamorphosis to adults, and by observing juvenilestrombids collected in the field. Complete adult modal actionpatterns (MAP's) associated with locomotion, feeding, and rightingof overturned shells are performed by S. maculatus juvenilesimmediately after metamorphosis. There are changes in the frequencyof the use of certain MAP's which are associated with variationsin shell shape and size. The unique strombid escape response to molluscivorous gastropods(Conns spp.) is not released until juvenile S. maculatus arethree weeks past metamorphosis and two millimeters in shelllength. At that stage, the complete response is released uponthe first encounter with a predator. Experience with a predatordoes not seem to lower the age or size criteria. During ontogeny there is a trend toward an increasing complexityof behavior which is paralleled by an increasing complexityof neural structure and general morphology. There are majorsteps in the ontogeny of strombid behavior which probably coincidewith neural and morphological stages. 相似文献
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SYNOPSIS. The iguanid lizard Basiliscus basiliscus in Panama is parasitized by Plasmodium basilisci and P. achiotense sp. nov. P. basilisci in this host is characterized by schizonts containing 4–14 merozoites, with schizonts parasitizing proerythrocytes containing more merozoites than those in erythrocytes. Asexual parasites lack cytoplasmic projections, while mature gametocytes are round or oval with regular margins.
P. achiotense is characterized by the combination of prominently pigmented, large schizonts containing 36–56 merozoites and oval or round gametocytes which are about 1/3 larger than those of P. basilisci.
EE-schizonts of P. basilisci were observed commonly in thrombocytes and occasionally in lymphocytes, and appeared early in experimental infections induced by blood inoculation. 相似文献
P. achiotense is characterized by the combination of prominently pigmented, large schizonts containing 36–56 merozoites and oval or round gametocytes which are about 1/3 larger than those of P. basilisci.
EE-schizonts of P. basilisci were observed commonly in thrombocytes and occasionally in lymphocytes, and appeared early in experimental infections induced by blood inoculation. 相似文献