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111.
应用光生物素标记参考菌株DNA比色法以DNA-DNA点杂交对类单胞菌属的分离菌株及参考菌株进行遗传学鉴定。在强日光灯下,光生物素标记DNA15min。以少量菌体法提取被测菌株的DNA,并将此DNA点种在硝酸纤维膜上;碱性磷酸酶偶联链霉抗生物素基物显色法DNA-DNA点杂交,颜色图形分析仪测定点杂交颜色强度。该方法鉴定结果与数值分类法的结果和复性率定量测定DNA-DNA同源性的结果基本相符。光生物素标记DNA比色法DNA-DNA点杂交鉴定类单胞菌是一种快速而简便的方法。 相似文献
112.
应用光生物素标记DNA荧光法微孔板DNA杂交测定类单胞菌的分离菌株和参考菌株DNA-DNA相关性.热变性DNA固化在96孔微孔板,光生物素标记DNA与固化DNA杂交,测定酶链霉抗生物素偶联β-D-半乳糖苷酶(Strept-avidin-conjugated β-D-galctosidase)作用于敏感荧光底物4-甲基荧光素-β-D-半乳糖苷(4-methylumbelliferyl-β-D-galactoside).在波长365nm激发450nm发射,荧光分析仪测定杂交的荧光强度.根据荧光强度,计算分离菌株和参考菌株DNA-DNA相关性.试验结果表明:光生物素标记ONA荧光法微孔板DNA杂交是更敏感的方法,与光生物标记DNA硝酸纤维膜比色法点杂交、DNA动力学测定DNA同源性,数值分类法的结果基本相符. 相似文献
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114.
TIAN Yi KONG Jie YANG Cuihua 《科学通报(英文版)》2006,51(19):2369-2374
The total yield of shrimp farming industry declined after WSSV broke out. It was only at the last 20 years that production had again begun to increase[1]. So far, shrimp farming industries mostly depend on capturing wild shrimps or wild post-larvae to sto… 相似文献
115.
SHEN Fafu YU Shuxun XlE Qingen HAN Xiulan FAN Shuli 《科学通报(英文版)》2006,51(9):1085-1094
Leaf senescence in plants is an essential develop- mental phase, and an understanding of senescence is important not only for pure scientific reasons, but also for practical purposes. During the last decade, a number of senescence-associated genes (SAGs) … 相似文献
116.
Using the genomic DNAs of maize and rice as probes respectively, the homology of maize and rice genomes was assessed by genomic in situ hybridization. When rice genomic DNAs were hybridized to maize, all chromosomes displayed many multiple discrete regions, while each rice chromosome delineated a single consecutive chromosomal region after they were hybridized with maize genomic DNAs. The results indicate that the genomes of maize and rice share high homology, and confirm the proposal that maize and rice are diverged from a common ancestor. 相似文献
117.
Expression and regulation of orphan receptor TR2 mRNA in germ cells of cryptorchid testis in rat and rhesus monkey 总被引:3,自引:0,他引:3
Expression and cellular localization of orphan receptor TR2 mRNA in relation to germ cell apoptosis in cryptorchid testes
of rat and rhesus monkey have been studied by usingin situ hybridization andin situ 3′-end labeling of DNA fragments (TUNEL). The results show that: (i) TR2 mRNA is specifically expressed in the germ cells,
mainly in the spermatocytes, round and elongated spermatids. The expression level of TR2 mRNA varies with the seminiferous
cycle, (ii) In the rat cryptorchid testes on days 3 and 5 after the surgery, the germ cells began to undergo apoptosis with
no evident decrease in TR2 mRNA level. On day 7.5, however, most germ cells underwent apoptosis, while the expression level
of TR2 mRNA declined markedly, and TR2 mRNA was rarely expressed on day 10 thereafter, (iii) On days 15 and 20 of the cryptorchid
testes of rhesus monkey, TR2 mRNA was only expressed in a few of primary spermatocytes and the mRNA was almost undetectable
on days 30, 45, 60. These results suggest that TR2 mRNA probably plays an important role in spermatogenesis and germ cell
apoptosis. 相似文献
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119.
Recently,graphene has attracted numerous interests from both fundamental and applied fields due to its excellent mechanical,thermal,electrical conductivity and other novel properties.This review gives an overview of recent progress on hybridization modifications of graphene with carbon nanomaterials.Some example applications of graphene-based nanohybrids in polymer composites,optical and conducting materials,high performance electrolyte materials and as well as other functional materials are summarized and discussed. 相似文献