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131.
虫生真菌的分子生物学检测技术 总被引:3,自引:0,他引:3
线粒体DNA探针、核糖体RNA编码DNA序列分析、随机扩增多态性DNA-聚合酶链式反应、基因组DNA探针和电泳核的,五类分子生物学技术在虫生真菌研究中已有应用。本对此作了介绍,着重阐述了RAPD-PCR技术的特点及其使用此技术的研究成果。 相似文献
132.
Marie-Hélène Moncel 《L'Anthropologie》2003,107(1):117-151
The site of Tata, located in Hungary, has yielded two famous “artistic objects” dated from the isotopic stage 5. However, this site is also famous for its lithic assemblage, most of which is smaller than 30 mm. Other sites in Central Europe have yielded microlithic assemblages, which are not always related to specific raw material conditions. Few human remains provide evidence that Neanderthals were the authors of these assemblages. The settlements are often linked to water springs and the fauna assemblages are composed of one or two great herbivores (deer, horses, rhinoceros and elephants). The analysis of fauna remains suggests that some of these animals could be hunted. The low frequency of rhinoceros and elephants and the partial skeletons do not allow us to know whether these animals have been hunted or scavenged in most cases. But some sites have yielded a higher frequency of these herbivores, which are often young specimens. Are we dealing with programmed specialised settlements in favourable areas for animals, either dead or alive? The herbivore bones are associated with very small flakes, showing the diversity of the human technical behaviours adapted to all kinds of subsistence patterns. The technological analysis of the assemblages, in particular of the cores, provides new patterns about the technological choice for flaking, which seems to belong to a specific tradition. This hypothesis is indirectly confirmed by comparative studies of several microlithic industries from the OIS 11 to 4-3, such as Vèrtesszölös in Hungary, Külna and Predmosti II in the Czeck Republic or the Pontinian complex in Italy. The microlithic assemblages are associated with various environments and could be one of the human responses to organise the stone tool production. It could also be evidence of another technological conception of the tools. The small artefacts could be used alone or hafted separately or grouped, and perhaps even to prepare wooden tools. The discoveries of both bone and wooden tools in some sites prove that the Neanderthal industrial world could be complex and diversified. 相似文献
133.
古代DNA研究实验技术 总被引:5,自引:1,他引:4
现代分子生物技术的发展,使从古代样品中获取微量DNA成为现实。在过去的十多年里,古DNA研究取得了重大进展,但实验方案还需要加以改进,其结果的分析与推论也需要多方面的验证。本综述着重介绍了古DNA研究的实验技术及可靠性分析。
Experimental Techniques for Ancient DNA Research
YANG Shu-juan1,LAI Xu-long1,2,TANG Xian-hua1,SHENG Gui-lian1,2
1.Faculty of Earth Sciences,China University of Geosciences,Wuhan,430074,China;
2.Institute of Life Sciences,China University of Geosciences,Wuhan,430074,China
Abstract:The development of modern molecular biological techniques makes it possible to study minimum DNA from ancient materials.During past decade,a lot of significant achievements on ancient DNA research have been made in many fields especially in molecular evolutionary biology.The nature of degradation and contamination of ancient DNA from ancient biological materials pose a dominating problem in ancient DNA research.Therefore,the experiments should be modified based on the modern molecular techniques and more factors should be considered when the results are analyzed.In this paper,authors review the general experimental protocols on sampling,extraction and amplification as well as authenticity of ancient DNA.
Key words:ancient DNA;authenticity;ancient DNA techniques 相似文献
134.
稻水象甲卵的空间分布型及抽样技术研究 总被引:2,自引:0,他引:2
本文利用Taylor幂法则和Iwao回归法对稻水象甲LissorhoptrusoryzophilusKuschel卵的空间分布型进行了测定 ,结果表明稻水象甲卵在田间呈聚集分布 ,且符合负二项分布 ,k值为 0 4 796。其种群聚集主要是由环境因子引起的。应用Iwao的抽样模型建立了稻水象甲卵的田间理论抽样数公式 :N =1D2 1 784 6M + 0 2 4 2 5 。并根据Gerrard的零频率模型建立了估计该种群平均密度的零频率模型 :X =1 5 787( -lnP0 ) 1 0 62 5。 相似文献
135.
136.
通过对中国西南部3种菖蒲属(Acorus L.)植物(菖蒲A.calamus L.、石菖蒲A.tatarinowii Schott和金钱蒲A.gramineus Soland.)的细胞学研究,发现分布在运动及四川的9个菖蒲居群中,有5个居群为四倍体(2n=4x=44),4个居群为六倍体(2n=6x=66)。其中四倍体见于滇南及川西南;六倍体见于滇中及滇西北,并为首次报道。在云南及贵州分布的石菖蒲及金钱蒲5个居群均为二倍体。讨论了菖蒲分布区从二倍本、三倍体、四倍体和六倍体4种不同倍性居群的分布规律和可能的演化关系,六倍体居群的产生很可能喜马拉雅造山运动有关。 相似文献
137.
The nature and persistence of seed quality effects produced by a range of seed production treatments was investigated in the autumn-sown onion crop. Genotypically equivalent seed lots raised in different glasshouses within the same year were found to germinate at significantly different rates. The seed lot which emerged earlier produced larger seedlings and this difference in size persisted throughout the growing period. In a comparison between the effects of hand crossing and self-pollination techniques the hand crossing method produced a much lower total seed yield but heavier seeds and larger plants. The induced effects persisted throughout the year but were not significant in the mature bulb characters. The implications of these results upon the control of seed production for plant breeding and genetical experiments is discussed. 相似文献
138.
Advances in salivary bioscience enable the widespread integration of biological measures into the behavioral and social sciences. While theoretical integration has progressed, much less attention has focused on analytical strategies and tactics. The statistical literature warns that common methods for comparing groups and studying associations can have relatively poor power compared to more modern robust techniques. Here we illustrate, in secondary data analyses using the USC Well Elderly II study (n = 460, age 60–95, 66% female), that modern robust methods make a substantial difference when analyzing relations between salivary analyte and behavioral data. Analyses that deal with the diurnal pattern of cortisol and the association of the cortisol awakening response with depressive symptoms and physical well-being are reported. Non-significant results become significant when using improved methods for dealing with skewed distributions and outliers. Analytical strategies and tactics that employ modern robust methods have the potential to reduce the probability of both Type I and Type II errors in studies that compare salivary analytes between groups, across time, or examine associations with salivary analyte levels. 相似文献
139.
Ioanna Kosmidou Shannnon Wooden Brian Jones Thomas Deering Andrew Wickliffe Dan Dan 《Journal of visualized experiments : JoVE》2013,(72)
Cryoballoon ablation (CBA) is an established therapy for atrial fibrillation (AF). Pulmonary vein (PV) occlusion is essential for achieving antral contact and PV isolation and is typically assessed by contrast injection. We present a novel method of direct pressure monitoring for assessment of PV occlusion.Transcatheter pressure is monitored during balloon advancement to the PV antrum. Pressure is recorded via a single pressure transducer connected to the inner lumen of the cryoballoon. Pressure curve characteristics are used to assess occlusion in conjunction with fluoroscopic or intracardiac echocardiography (ICE) guidance. PV occlusion is confirmed when loss of typical left atrial (LA) pressure waveform is observed with recordings of PA pressure characteristics (no A wave and rapid V wave upstroke). Complete pulmonary vein occlusion as assessed with this technique has been confirmed with concurrent contrast utilization during the initial testing of the technique and has been shown to be highly accurate and readily reproducible.We evaluated the efficacy of this novel technique in 35 patients. A total of 128 veins were assessed for occlusion with the cryoballoon utilizing the pressure monitoring technique; occlusive pressure was demonstrated in 113 veins with resultant successful pulmonary vein isolation in 111 veins (98.2%). Occlusion was confirmed with subsequent contrast injection during the initial ten procedures, after which contrast utilization was rapidly reduced or eliminated given the highly accurate identification of occlusive pressure waveform with limited initial training.Verification of PV occlusive pressure during CBA is a novel approach to assessing effective PV occlusion and it accurately predicts electrical isolation. Utilization of this method results in significant decrease in fluoroscopy time and volume of contrast. 相似文献
140.