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161.
162.
One-step isolation of plant DNA suitable for PCR amplification 总被引:4,自引:0,他引:4
We report a one-step extraction technique for the isolation of plant DNA, DNA suitable for amplification by PCR can be produced
from leaf material smaller than 0.3 mm2 in less than 20 min, with no tube changes. The method was tested on several plant specA00AK020ies. The described method was
found to extract DNA that could be amplified without any further purification or treatment. The isolated DNA was amplified
using a universal chloroplast primer set. The method was validated by comparing size of PCR products generated by the novel
method to PCR products generated using standard DNA isolation techniques. 相似文献
163.
164.
JANET WARNER REID CARLOS EDUARDO FALAVIG NA ROCHA 《Zoological Journal of the Linnean Society》2003,139(1):81-92
Members of a new genus and species of harpacticoid copepod crustacean appeared in samples from semi-terrestrial (moist arboreal mosses, wet soil) and aquatic (bromeliad tanks, Sphagnum moss, rock pools, stream) habitats in a remnant of the Atlantic Forest in south-eastern Brazil. The new taxon, for which we propose the name Pindamoraria boraceiae sp. nov. , is distinguished by a unique combination of characters, in particular the segmentation and setation pattern of legs 1–4 in both sexes, the structure of leg 5 in the female, and the strongly modified claw of the maxilliped in the male. It most resembles the canthocamptid genera Moraria , Pseudomoraria , Morariopsis and Paramorariopsis . Both previous records of species of Moraria from South America refer to members of Antarctobiotus , which is not considered a member of the Moraria group: Moraria (Kuehneltiella) neotropica Löffler has previously been transferred to Antarctobiotus ; and we propose herein the transfer of Moraria kummeroworum Ebert & Noodt to Antarctobiotus as well. In the New World, the genus Moraria extends only as far south as Honduras; and Pseudomoraria , Morariopsis and Paramorariopsis are Old World genera. The new species from Brazil is therefore the only member of the Moraria group known from South America. © 2003 The Linnean Society of London, Zoological Journal of the Linnean Society , 2003, 139, 81–92. 相似文献
165.
D Costalago NAF Miranda NA Strydom R Perissinotto 《African Journal of Aquatic Science》2016,41(4):389-398
South African estuarine systems are becoming increasingly altered by anthropogenic and environmental factors, but the consequences of such changes for these systems are still not fully understood. The most common approach for evaluating the ecological status of aquatic systems is studying their associated foodwebs. Due to their high abundance and important ecological role, the larvae of estuarine round herring Gilchristella aestuaria (Gilchrist, 1913) are key candidates for examining the foodweb structure and function of southern African estuaries. The foodwebs and trophic interactions of G. aestuaria larvae in six estuaries in South Africa were compared using larvae sampled in November 2013 and analysed using δ13C and δ15N and Bayesian isotopic mixing models. The main prey type for G. aestuaria larvae in all estuaries was zooplankton. We found a high similarity among the Kariega, Gamtoos, Great Fish and Sundays estuaries in terms of consumers and potential sources for both δ13C and δ15N signatures. Significant differences were found in δ13C values among marine-dominated estuaries, such as the Kromme Estuary, and the more freshwater-dominated systems. In addition, in the Kromme Estuary particulate organic matter was very important in the diet of G. aestuaria larvae. Our results suggest that both food availability and physical environmental parameters strongly affect the diet and condition of G. aestuaria and, consequently, the entire foodweb in the system. 相似文献
166.
γ-聚谷氨酸(γ-PGA)是一种天然高分子可降解、环境友好型的新型阴离子聚合物。目前发现多种芽孢杆菌、古细菌和一种真核生物均可合成γ-PGA。根据其合成是否需要外加谷氨酸分为谷氨酸依赖性和谷氨酸非依赖型。γ-PGA的合成基因分为结合型的cap系和游离型的pgs系,其表达产物组成的γ-PGA合成酶复合体调节着γ-PGA的合成和转运。由于γ-PGA具有水溶性好、保湿性好、吸水性好、良好的生物兼容性和生物可降解性、可食用、对环境无污染等优点,在医药、农业、食品、环境、化妆品等领域具有广泛的应用前景。主要对γ-PGA的结构特点、微生物合成、相关基因、合成机理、应用、诱变处理进行综述。以期通过物理和化学等技术的诱变,获得γ-PGA的高产菌株,为提高γ-PGA产量提供依据。 相似文献
167.
Tania M Perehinec Saara NA Qazi Sanyasi R Gaddipati Vyvyan Salisbury Catherine ED Rees Philip J Hill 《BMC molecular biology》2007,8(1):80
Background
The Gateway recombinatorial cloning system allows easy and rapid joining of DNA fragments. Here we report the construction and evaluation of three different Gram-positive vectors that can be used with the Multisite Gateway cloning system to rapidly produce new gene arrangements in plasmid constructs for use in a variety of Gram-positive bacteria. 相似文献168.
为了探讨肌肉注射Ag85A DNA疫苗能否在肿瘤宿主,一个低细胞免疫应答的机体内激发Th1型细胞免疫应答,将6~8周龄BALB/c雌性小鼠随机分成实验组(Ag85A-V1Jns.tPA组),空质粒组(V1Jns.tPA组)和生理盐水组3组,将生长旺盛的Meth-A细胞接种于各组小鼠右侧背部皮下,每只小鼠2×105个细胞,1d后于小鼠大腿肌肉内分别注射100μL Ag85A-V1Jns.tPA(1 g/L),V1Jns.tPA(1 g/L)或生理盐水。每10 d 1次,共3次,于末次注射后第8 d,无菌取脾,分离细胞进行培养。检测NK细胞活性以及脾细胞培养上清中IFN-γ含量。结果显示:实验组平均NK细胞杀伤率以及脾细胞培养上清中IFN-γ含量较空质粒组和生理盐水组均显著增高,而空质粒组和生理盐水组之间未见有意义的变化。提示肌肉注射Ag85A DNA疫苗可以提高Meth-A纤维肉瘤荷瘤小鼠Th1细胞免疫功能。 相似文献
169.
人-禽双价流感新型DNA疫苗构建及免疫保护实验研究 总被引:2,自引:0,他引:2
流感病毒是威胁人类和动物健康的重要病原. 研究表明, 流感大流行株的形成与人流感和禽流感毒株基因重配密切相关. 因此在目前流感流行趋势下, 在人流感和禽流感疫苗开发中考虑对人流感和禽流感流行亚型进行共预防具有重要意义. 本研究针对人-禽多价流感疫苗进行了尝试, 构建了共表达H5亚型HA和H3亚型主要抗原区HA1的DNA疫苗pVAX1-H5/H3, 并进行了小鼠免疫攻毒研究. 结果表明, 攻毒前pVAX1-H5/H3有效诱导小鼠产生了针对 H5HA和H3HA1的体液抗体和细胞免疫应答. 当采用H5亚型和H3亚型流感病毒攻击时, pVAX1-H5/H3实验组小鼠对病毒攻击产生了抵抗作用, 显示了更快的体重回复及肺部病毒清除速度. 在H3亚型流感保护方面, pVAX1-H5/H3作用显著优于单表达H3HA1的pVAX1-H3. 结果证实, 共表达双亚型HA策略可对相关流感病毒攻击产生保护, 不同HA间未发现免疫干扰现象, 同时存在潜在的增益效果. 本研究为人-禽多价流感疫苗的研发奠定了基础. 相似文献
170.