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21.
对山东省5个地区的62份紫椴单株进行遗传多样性的AFLP分析.结果表明:9对引物共产生1370条多态带,多态带比例为99.70%,平均Nei’s基因多样度和平均香农信息指数分别为0.2132、0.3405,供试材料遗传多样性较高,共产生182条特异性条带,据此可将82.3%的紫椴单株辨别出来,表明AFLP在分子水平上具有鉴别紫椴单株的潜力;单株间相似系数为0.3911-0.7953,平均值为0.5761,在相似性系数为0.60处,可将62个单株分成12组,分组情况与来源没有严格的一致性.  相似文献   
22.
We evaluated the whole body distribution of 2‐deoxy‐2‐[18F]fluoro‐d ‐glucose (18F‐FDG) in seven beagle dogs using positron emission tomography/computed tomography. The mean and maximum standard uptake values (SUV) for various tissues were computed. The SUV of the aortic blood pool was 0.65±0.19. Moderate uptake was present in brain (3.40±1.01). Mild uptake was present in orbital muscles, soft palate, laryngeal and pharyngeal region, mandibular salivary gland, myocardium, liver, pancreas, kidney, and intestine. 18F‐FDG uptake would be normally higher in these tissues because of normal physiologic activity. Mean and maximum SUV values of the eye, skeletal muscle, bone tissue, spleen, adrenal gland, stomach, tongue, gall bladder, and lung were similar to or lower than that of the aortic blood pool. These data provide a normal baseline for comparing pathologic 18F‐FDG uptake.  相似文献   
23.
An inhibitory effect of the phenolic compounds released from the roots of K21, a newly bred potent allelopathic rice, was investigated in comparison to its male parent, Kouketsumochi, and its female parent, Dongjinbyeo. The inhibitory rates of the root exudates of K21 and both of its parents, collected at 5 day intervals, on the shoot growth of Echinochloa crus-galli var. praticola exhibited an increasing trend from 19–34 days after seeding (DAS). However, the root exudates of K21, at concentrations of 0.5, 1.0, and 2.0%, showed a greater inhibitory effect than those of its female parent on the growth of E. crus-galli var. praticola at the earlier collection dates. Nine phenolic compounds were identified; the total amount of phenolic compounds in the exudates increased from 19–34 DAS in both K21 and its male parent, but not much in the female parent. The subsequent increase in the amount of total phenolic compounds in the root exudates of the later investigation dates and the trend of increasing inhibitory rates on the shoot growth of E. crus-galli var. praticola at higher exudate concentrations imply that the increased amount of phenolic acids in the root exudates of K21 secreted on the subsequent dates could be related to its greater allelopathic effects.  相似文献   
24.
本研究采用~(14)C 标记的多菌灵,通过棉苗的叶部和根部两个途径分别给药处理,结果说明:多菌灵象其它许多内吸杀菌剂一样,在植物体中随蒸腾流可以在木质部内迅速传导,而在韧皮部内传导是相当微弱的。多菌灵在棉苗各个部位的代谢速度是不相同的。通过根部给药处理后14天,根部、茎部及叶部母体化合物(MBC)的含量分别为25.3%,32.3%和56.7%。多菌灵在棉苗根部降解速度最快,茎部次之,叶部最慢。多菌灵在棉苗中的整个代谢速度较缓慢,14天后仍有48.5%的原药留在棉苗中。其主要代谢产物是2-氨基-苯并咪唑(2-AB)和水溶性轭合物。  相似文献   
25.
 1973~2005年对我国东北地区山葡萄抗寒的种质资源(品种、品系) 进行种内杂交, 并与果实高糖低酸、不抗寒的欧亚种酿造葡萄品种进行种间杂交、回交和重复杂交(8种杂交模式) , 共73个组合, 杂种苗成活10 544株。共分离出低酸高糖3 049株, 占杂种苗总株数2819%。8种杂交模式果实总酸含量(低→高) 排列顺序是: (山—欧) F2 ×欧亚种→ (山—欧) F1 ×欧亚种→山葡萄×欧亚种→ (山—欧) F1 × (山—欧) F1 → (山—欧) F2 × (山—欧) F2 → (山—欧) F2 ×山葡萄→ (山—欧) F1 ×山葡萄→山葡萄×山葡萄。果实糖含量(高→低) 排列顺序是: (山—欧) F2 ×欧亚种→ (山—欧) F1 ×欧亚种→ (山—欧) F2 × (山—欧) F2 → (山—欧) F1 × (山—欧) F1 →山葡萄×欧亚种→ (山—欧) F1 ×山葡萄→ (山—欧) F2 ×山葡萄→山葡萄×山葡萄。遗传规律是: 山葡萄种内和种间杂交后代( F1 ~F4 )果实总酸和糖含量性状分离, 表现为连续分布, 趋向于高酸和低糖亲本, 杂交组合中高酸低糖亲本越多,分离出的高酸低糖单株越多, 为多基因控制的数量性状遗传。已从(山—欧) F1 ×山葡萄、(山—欧) F1× (山—欧) F1和(山—欧) F2 × (山—欧) F2 杂交模式中选育出酿造干红山葡萄酒新品种‘左优红’、品系94-7-75、94-8-168、98-17-121和酿造冰红酒新品系2002-1-135。  相似文献   
26.
本研究采用聚丙烯酰胺凝胶电泳(PAGE)法检测了松辽黑猪28个样本的13个血清蛋白(酶)位点。结果表明:除Alb、Pa2、Cp为单态外,Pa1、Po1、Po2、Tf、Ptf、Akp、Hpx、Am1、Am2、Es均存在多态性,分别受2~4个等位基因控制。卡方检验结果表明,Pa1、Pa2、Ptf、Akp不处于Hardy-Weinberg平衡状态,其余的Po1、Po2、Tf、Am1、Am2、Hpx、Es都处于Hardy-Weinberg平衡状态。松辽黑猪群体内有效等位基因数、遗传杂合度、以及遗传均质度分别为2.077 9、0.508 3和0.128 8。  相似文献   
27.
两个双矮地方种质中新矮生基因的遗传和等位性分析   总被引:6,自引:0,他引:6  
对黔农和特矮两个双矮地方种质株高性状的遗传分析结果表明,黔农和特矮的矮生性均由2对隐性矮生基因控制,其中各有1对矮生基因与sd-1等位,另1对与sd-1不等位。黔农中两对矮生基因降低株高的效应不同,与sd-1不等位的矮生基因控制的株高比sd-1略矮;而特矮的两对矮生基因具有相同的降低株高效应。将分别来自黔农和特矮的携带新半矮生基因的材料命名为“新黔矮”和“新特矮”,各携带新的半矮生基因sd-q(t)和sd-e(t);其中新黔矮携带sd-q(t)与sd-g(t)等6个矮秆半矮秆基因均不等位。新黔矮在每穗粒数、结实率和千粒重等农艺性状上表现较好,有希望应用在育种和生产上替代sd-1。  相似文献   
28.
Although embryo cryobanking was applied to Syrian golden and to Campbell's hamsters, no attempt has been made at freezing embryos in Djungarian hamsters. Four‐cell stage embryos were flushed from the reproductive ducts of pregnant females before noon of the third‐day post coitum and frozen in 0.25‐ml straws according to standard procedures of slow cooling. A mixture of permeating (ethylene glycol) and non‐permeating (sucrose) cryoprotectants was used. The thawing was performed by incubating at RT for 40 s followed by 40 s in a water bath at 30.0°C. Most (66.7%) of the non‐frozen four‐cell embryos developed up to the morula stage in rat one‐cell embryo culture medium (R1ECM). The use of hamster embryo culture medium (HECM) yielded fewer morulas (18.2%) during the same 24‐h period of culture. The rate of embryo's surviving the freezing–thawing procedures, as estimated by light microscopy, was 60.7–68.8%. After 24‐h culturing in R1ECM, 64.7% of frozen–thawed four‐cell embryos developed and all of them reached the morula stage. Supplementation of R1ECM with GM‐CSF (2 ng/ml) improved the rate of Djungarian hamster frozen–thawed embryo development: 100% of the four‐cell stage embryos developed, 50% of them achieved the morula stage, and 50% developed even further and reached the blastocyst stage within 24 h of culturing. This study reports the world's first successful transfer of frozen–thawed Djungarian hamster embryos yielding term pups. Taken together, the results of this study demonstrate the possibility of applying some key reproductive technologies, that is, embryo freezing/cryopreservation and in vitro culture, to Djungarian hamsters.  相似文献   
29.
一、前言多菌灵(Carbendazim,MBC),化学名称:0一二甲基-N-2-苯并咪唑氨基甲酸酯。它是一种高效、低毒、广谱的内吸杀菌剂。呋喃丹(Carbofuran,Furadan),化学名称:2,3-二氢-2,2一二甲基-F-苯并呋喃-N-甲基氨基甲酸酯。它是一种广谱杀虫、杀螨、杀线虫剂。具有触杀、内吸和胃毒作用。多菌灵和呋喃丹的合剂棉种包衣对于棉花苗期病虫害的防治效果显著。在我国,它被视为一种经济、有效的防治手段(Shen et al.  相似文献   
30.
The growth of many service industries among American metropolitan areas stem from an eclectic set of forces. These include market penetration effects of increasing importance of services throughout the economy, agglomeration effects in immature and deregulated industries, and institutional and infrastructure constraints. These diverse forces are interpreted as urbanization and localization economies. A cycle of centralization of 27 fast growing service industries is documented for MS As in the period 1977-84. The two agglomeration effects are tested directly, using a power function model that relates employment and establishment growth to MSA size and initial level of employment in a local industry. Localization economies rather than the general advantages of metropolitan size best explain the growth patterns. This result implies that service industrial complexes are rapidly emerging in American metropolitan areas.  相似文献   
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