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991.
利用Insertion/Deletion(InDel)分子标记检测玉米互交种混杂的原理及应用 总被引:1,自引:0,他引:1
尽管分子标记广泛用于玉米品种纯度鉴定,但由于互交种基因组具有相同的基因,现有的分子标记技术尚不能对互交种的混杂进行有效判定。本研究基于玉米互交种胚乳等位基因二倍剂量关系,利用Insertion/Deletion(InDel)标记在PCR指数扩增期对等位基因扩增相对量的观察值与理论值进行统计分析,通过概率对互交种进行判定。经过筛选,亲本B73、Mo17间存在共显性差异的8个InDel标记中,5个标记的PCR扩增质量满足互交种样本(正交种:B73×Mo17,反交种:Mo17×B73)的鉴定要求。这些标记以不同的循环数进行PCR扩增,发现37个循环是处于指数扩增期的最佳鉴定时期。同一标记在每个样本中以37个循环数进行3次扩增重复,统计分析发现:不同标记在杂交种叶片DNA中等位基因扩增相对量与理论比1的统计概率值从6.50E-08到1.000不等,证实标记在等位基因间的扩增效率并不完全一致。对互交种胚乳等位基因扩增相对量进行卡方测验,4个InDel标记能够对互交种样本进行准确区分,所得概率符合判定标准。标记110仅能准确判定正交种,对反交种样本的统计概率不满足反交种判定的概率标准。结果显示,该分子标记方法可成功用于玉米互交种的判定。 相似文献
992.
WRKY转录因子的结构及其在植物抗逆境胁迫中的功能 总被引:2,自引:0,他引:2
WRKY转录因子是一超级基因家族,广泛存在于高等植物界,参与了植物的多种生理生化与生长发育过程,在植物应对外界逆境胁迫发挥了十分重要的功能。WRKY超级基因家族由于其N端包括保守的WRKYGQK氨基酸序列而得名,通过其保守的氨基酸序列与靶标基因启动子区W-box相互结合,从而对靶标基因进行表达调控。本文主要综述了WRKY基因的结构特征及其在植物应答外界逆境胁迫过程中的功能,为进一步研究WRKY超级基因家族提供有益的启示。 相似文献
993.
沙地不同密度樟子松林地土壤水分的垂直变化 总被引:1,自引:1,他引:0
通过在辽宁省章古台试验区对沙地不同密度樟子松林地土壤水分垂直变化规律的研究,结果表明:该地区樟子松林分不论密度大小,雨季土壤含水量整体上明显高于春季;不同林分密度的樟子松林土壤水分含量在不同时期不同层次有所不同,春季试验地各层土壤的含水量从上到下大体上呈下降趋势,北试验地0~60cm层次土壤含水量下降的比较明显,南试验地在60~100cm层次间出现了急剧下降的情况;雨季0~40cm土层间,试验地土壤水分含量都呈上升趋势,40~150cm这几个层次间,试验地土壤含水量均呈下降趋势,且在40~100cm的层次上2试验地下降的幅度都比较大。 相似文献
994.
Woo Duck Seo Jun Young Kim You-Chun Song Jun-Hyun Cho Ki Chang Jang Sang-Ik Han Ji-Eun Ra Seong-Hwan Oh Hyeon-Jung Kang Byung-Joo Kim Nam-In Baek Rak-Hun Jeong Min Hee Nam 《Journal of Crop Science and Biotechnology》2013,16(1):63-68
The main objectives of this study were to investigate physicochemicals and antioxidant activities of new red rice (Oryza sativa cv. Gunganghongmi (GH)) by comparing normal brown (Nampyeongbyeo, NB) and reported red rice (Jukjinjubyeo, JB) in Korea. The nutritional constituents, including protein, oil, sugar, fatty acid, GABA, and γ-oryzanol were not significantly different between normal brown and colored rice. However, the ethanol extract of GH showed the highest phenolic content (24.7 ± 1.3 mg g?1). The ethanol extracts of GH showed higher scavenging activities against DPPH (0.2 mg mL?1 = 62.1 ± 2.5%) and ABTS (0.2 mg mL?1 = 63.2 ± 3.5%) radicals. Moreover, GH more inhibited LPS-induced nitric oxide (NO) production (13.2 ± 1.4 μM) than JB (18.3 ± 2.3 μM) and NB (22.1 ± 1.4 μM) at the same concentration (0.2 mg mL?1) without cytotoxicity. These results suggest that new red rice (GH) would be considered to be new functional rice due to its anti-oxidative effect and high nutrition. 相似文献
995.
996.
Hem Raj Pant Bishweshwar Pant Chan Hee Park Han Joo Kim Dong Su Lee Leonard D. Tijing Bo Sang Hwang Hak Yong Kim Cheol Sang Kim 《Fibers and Polymers》2013,14(6):970-975
In this work, the reduced graphene oxide (RGO) sheets were effectively uploaded through nylon-6 fibers using combined process of electrospinning and hydrothermal treatment. Good dispersion of graphene oxide (GO) with nylon-6 solution could allow to upload GO sheets through nylon-6 fibers and facilitate the formation of spider-wave-like nano-nets during electrospinning. GO sheets present on/into nylon-6 spider-wave-like nano-nets were further reduced to RGO using hydrothermal treatment. The impregnated GO sheets into nylon-6 nanofibers and their reduction during hydrothermal treatment were confirmed by FE-SEM, TEM, FT-IR and Raman spectra. The electrical characteristics of pristine nylon-6, GO/nylon-6 and RGO/nylon-6 nanofibers were investigated and it was found that RGO/nylon-6 composite mat had better electrical conductivity than others. The formation of spider-wave-like nano-nets as well as indirect route of incorporation of RGO sheets on electrospun nylon-6 mat may open a new direction for future graphene/polymer electronics. 相似文献
997.
In this study, biodegradable composites were prepared using cellulose nanowhiskers and poly(lactic acid). For processing at high temperature over 200 °C, cellulose nanowhiskers were prepared by ultra-sound treatment, with the high thermal stability of natural cellulose. The nanowhiskers were confirmed using transmission electron microscopy, X-ray diffraction, and thermo-gravimetric analysis. Surface modification of the cellulose nanowhiskers was performed to increase the adhesion between hydrophilic nanofillers and hydrophobic polymer matrix. The dynamic mechanical thermal analysis of the composites showed better reinforcing effect of the modified cellulose nanocrystals. The effects of cellulose nanowhiskers on the biodegradability of poly(lactic acid) were studied using a microbial oxidative degradation analyzer. 相似文献
998.
This study examined the mechanical properties of worsted fabrics woven using various rapier weaving looms. For this purpose, the warp and weft yarn tensions during weaving were measured on the three types of rapier looms, and the fabric mechanical property changes due to the warp and weft tension differences were measured and analyzed according to the fabric position and particular rapier loom using the KES-FB system. The warp tension variation along the loom width direction in P-GTX loom showed the lowest value compared to FAST and THEMA looms. The warp tensions on the central part of the three types of looms were much higher than those on the left and right sides of the looms. The extensibility and bending rigidity of the fabric woven by P-GTX rapier loom showed lower values than those of FAST and THEMA looms, which appears to have originated from the low warp and weft weaving tensions of P-GTX rapier loom. On the other hand, the compressional property and shear modulus showed compromised results due to lateral deformation by compression and constraint deformation of the warp and weft by shear. The friction coefficient of the fabric surface woven by FAST loom showed the lowest value due to the flatter surface by the high warp tension. The mechanical properties of the fabric loaded by a high warp tension on the central part of the loom were also affected by the high weft yarn crimp due to the wider spacing between warp yarns by the higher warp tension during weaving, which makes the surface of the central part of the fabric flatter and smoother than the edge part of the fabric. 相似文献
999.
Yong-Chan Chung Jae Won Choi Young Jae Jung Samsook Han Byoung Chul Chun 《Fibers and Polymers》2013,14(12):2069-2076
Polyurethane (PU) copolymer is laterally linked with three kinds of metal ion indicator (calcein, calmagite, or eriochrome black T), with which free metal ion in aqueous solution is intended to be detected by PU color change. Metal ion detection by the indicator-PU fails due to the poor permeation of hydrophilic metal ion into hydrophobic PU layer. Instead, three surfactants with different ionic head groups, aerosol OT (AOT), cetyltrimethylammonium bromide (CTAB), and sodium dodecylsulfate (SDS), are tested for metal ion. Cationic CTAB exhibits an instant PU color change, but anionic AOT and SDS do not respond at all. Reason for the selective detection of cationic surfactant is the complex formation between cationic surfactant and indicator. Molecular interactions between PUs are affected by the laterally linked indicators based on the results by infrared spectra and differential thermal analysis. UV-vis spectra reveal that extra peak arising from the linked indicator appears compared to plain PU. The lateral linking of indicator to PU demonstrates, as well as the selective surfactant detection, a 454 % increase in tensile strength and reproducible shape recovery as high as 99 % compared to plain PU. 相似文献
1000.
Ji-young Jung Eui-hwa Nam Seol-hee Park Seung-hee Han Cheol-yong Hwang 《Journal of veterinary science (Suw?n-si, Korea)》2013,14(2):199-205
In humans, skin barrier dysfunction is thought to be responsible for enhanced penetration of allergens. Similar to conditions seen in humans, canine atopic dermatitis (CAD) is characterized by derangement of corneocytes and disorganization of intercellular lipids in the stratum corenum (SC) with decreased ceramide levels. This study was designed to evaluate the effects of a moisturizer containing ceramide on dogs with CAD. Dogs (n = 20, 3~8 years old) with mild to moderate clinical signs were recruited and applied a moisturizer containing ceramide for 4 weeks. Transepidermal water loss (TEWL), skin hydration, pruritus index for canine atopic dermatitis (PICAD) scores, and canine atopic dermatitis extent and severity index (CADESI) scores of all dogs were evaluated. Skin samples from five dogs were also examined with transmission electron microscopy (TEM) using ruthenium tetroxide. TEWL, PICAD, and CADESI values decreased (p < 0.05) and skin hydration increased dramatically over time (p < 0.05). Electron micrographs showed that the skin barrier of all five dogs was partially restored (p < 0.05). In conclusion, these results demonstrated that moisturizer containing ceramide was effective for treating skin barrier dysfunction and CAD symptoms. 相似文献