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991.
Bing Xu Shaolin Wang Yan Jiang Linlin Yang Ping Li Caixia Xie 《Animal biotechnology》2013,24(4):217-225
Grass carp, Ctenopharyngodon idellus (Valenciennes, 1844), is an economically important species widely cultured in the world, but its genome research resources are largely lacking. The objectives of this study were to construct normalized cDNA libraries for efficient EST analysis, to generate ESTs from these libraries, and to identify EST-related molecular markers such as microsatellites and single nucleotide polymorphisms (SNPs) for genetic analysis of this species. A total of 6,269 ESTs were generated representing 4,815 unique sequences, from which 105 putative microsatellites and 5,228 SNPs were identified. These genome resources provide the material basis for future genetic and functional analyses in this species. 相似文献
992.
The objective of this study was to analyze the clinical manifestation, imaging characteristics, genotype, and the relationship
between the three aforementioned parameters in two pedigrees suffering from spinocerebellar ataxia. To evaluate the clinical
manifestation of the two pedigrees and to compare the characteristics, we performed the MRI analysis of some patients from
both pedigrees, while 2 ml of the peripheral blood sample was collected for gene analysis. The gene analysis data showed that
pedigree 1 was certified spinocerebellar ataxia type-2 (SCA2); the CAG repeats in the proband, proband’s mother, and proband’s
brother were 44, 36, and 38, respectively. The MRI revealed brainstem cerebellar atrophy and “cross sign” and “ordinate sign”
of pons. Pedigree 2 was certified SCA1; the CAG repeats of the proband, proband’s aunt, and proband’s asymptomatic cousin
were 60, 51, and 52, respectively. The MRI revealed cerebellar atrophy in these individuals. We, therefore, concluded that
it was difficult to diagnose the SCA subset solely through the clinical manifestation. The imaging characteristics analysis
and final diagnosis depended basically on gene analysis data. 相似文献
993.
994.
A β-glucosidase effectively releasing diosgenin from spirostanosides of Dioscorea zingiberensis C. H. Wright (DZW), named AfG, was purified from a strain of Aspergillus fumigates. The molecular weight of AfG was 113 kDa. Analysis of protein fragments by ESI-Q-TOF indicated that AfG was a β-glucosidase.
The circular dichroism spectrum suggested that the main secondary structure of AfG in Milli-Q water was α-helixes. Atomic
force microscopy revealed that it was a globular protein. AfG maintained high activity from pH 3.6 to 5.0 and from 50 to 90°C.
With the strong heat stability, AfG retained 55% of its original activity at 65°C for 120 h. AfG utilized muti-3-O-glycosides
of various steroidal saponins from DZW as substrate, such as trillin, diosgenin diglucoside, dioscin, deltonin and gracillin,
to yield diosgenin, suggesting the possibility of producing diosgenin from total saponins of DZW using a single enzyme. 相似文献
995.
Xiaolian Gu Ping Zhuang Feng Zhao Xiaotao Shi Xiaorong Huang Guangpeng Feng Tao Zhang Jianyi Liu Longzhen Zhang Boyd Kynard 《Environmental Biology of Fishes》2017,100(1):27-33
Experiments were conducted in artificial stream tanks with juvenile Chinese sturgeon, Acipenser sinensis, captured in the Yangtze Estuary to test two null hypotheses (1) juveniles have no preference for white or black substrates, and (2) white or black substrate color has no effect on juvenile feeding efficiency on the barcheek goby,Rhinogobius giurinus, a dark-colored prey of wild juveniles. Juveniles strongly preferred white substrate. However, in feeding tests, feeding efficiency by juveniles was similar on white or black substrates. Thus, substrate color had no effect on feeding efficiency. Results suggest the innate preference for white substrate is not a visual adaptation for capturing prey on a contrasting background, but is an adaptation predisposing juveniles to seek light-colored sandy substrate where forage abundance is greatest. 相似文献
996.
辽宁棉区棉蚜抗药性监测与治理抗性研究 总被引:5,自引:0,他引:5
应用FAO推荐的微量毛细管点滴法,测定了棉蚜对六种常用杀虫剂的LD50,并与敏感蚜比较。得出抗药性倍数。棉蚜对有机磷杀虫剂的抗药性,增加缓慢,从1960年至今增加了500~700倍。而对于拟菊酯类杀虫剂的抗性增加较快,仅3~4年就达到667。7~9937.4倍。每年增加1.5~2倍。本项研究还应用棉蚜的防治指标和综合治理措施,对抗性棉蚜进行了治理抗性的试验研究。 相似文献
997.
Jesús Díez 《Biological invasions》2005,7(1):3-15
In the last two centuries, several species of Australian eucalypts (e.g. Eucalyptus camaldulensis and E.␣globulus) were introduced into the Iberian Peninsula for the production of paper pulp. The effects of the introduction of exotic root-symbitotic
fungi together with the eucalypts have received little attention. During the past years, we have investigated the biology
of ectomycorrhizal fungi in eucalypt plantations in the Iberian Peninsula. In the plantations studied, we found fruit bodies
of several Australian ectomycorrhizal fungi and identified their ectomycorrhizas with DNA molecular markers. The most frequent
species were Hydnangium carneum, Hymenogaster albus, Hysterangium inflatum, Labyrinthomyces donkii, Laccaria fraterna, Pisolithus albus, P. microcarpus, Rhulandiella berolinensis, Setchelliogaster rheophyllus, and Tricholoma eucalypticum. These fungi were likely brought from Australia together with the eucalypts, and they seem to have facilitated the establishment
of eucalypt plantations and their naturalization. The dispersion of Australian fungal propagules may be facilitating the spread
of eucalypts along watercourses in semiarid regions increasing the water lost. Because ectomycorrhizal fungi are obligate
symbionts, their capacity to persist after eradication of eucalypt stands, and/or to extend beyond forest plantations, would
rely on the possibility to find compatible native host trees, and to outcompete the native ectomycorrhizal fungi. Here we
illustrate the case of the Australasian species Laccaria fraterna, which fruits in Mediterranean shrublands of ectomycorrhizal species of Cistus (rockroses). We need to know which other Australasian fungi extend to the native ecosystems, if we are to predict environmental␣risks
associated with the introduction of Australasian ectomycorrhizal fungi into the Iberian Peninsula.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
998.
体细胞核移植技术已经在基础研究领域与产业化应用领域体现出了重要的价值,因而体细胞核移植技术及其相关研究已经成为了生物领域的持续性研究热点,但是围绕体细胞核移植技术仍然存在许多质疑,其中最主要的就是体细胞核移植的效率较低。尽管如此,体细胞核移植研究仍然在近年来取得了令人瞩目的成就,包括小鼠与恒河猴核移植胚胎干细胞系的建立。该文就体细胞核移植的研究历史与进展进行简要的论述,同时针对体细胞核移植研究中的细胞重编程与治疗性克隆研究中的发展与问题进行剖析,希望能够积极推动治疗性克隆的研究进展,加速核移植与干细胞技术在产业化领域中的应用。 相似文献
999.
由于地理环境优越、海拔跨度大、生境异质性高、人为影响小等原因,贵州施秉喀斯特世界自然遗产提名地的苔藓植物丰富,共有50科128属286种(含变种和亚种),其中苔类17科23属43种,藓类33科105属243种。其优势科、属均反映了该区系的温带向热带过渡的性质。区系地理成分分析结果显示,该区苔藓植物北方温带成分、热带成分和东亚成分分别占37.12%、31.82%和30.30%,其中中国特有分布型占12.12%,反映了施秉喀斯特苔藓植物区系具有温热并重、东亚色彩浓厚、特有性较高的特征。通过对施秉喀斯特与其它五个区域的苔藓区系进行对比发现.施秉苔藓区系丰富度高,与同为云贵区的香纸沟、马岭河、罗平喀斯特地区亲缘关系最近。 相似文献
1000.